WO2015119554A1

WO2015119554A1 - Radio nodes and methods therein for selecting a method for scaling a transmit power and adapting a receiver configuration

Info

Publication number: WO2015119554A1
Application number: PCT/SE2015/050032
Authority: WO
Inventors: Muhammad Kazmi; Yu Yang
Original assignee: Telefonaktiebolaget LM Ericsson AB
Current assignee: Telefonaktiebolaget LM Ericsson AB
Priority date: 2014-02-06
Filing date: 2015-01-15
Publication date: 2015-08-13
Anticipated expiration: 2016-08-06

Abstract

Method performed by a first radio node (640) for selecting a method for scaling a transmit power of one or more radio signals transmitted by a second radio node (611) to a third radio node (671). The second radio node (611) uses a modulation scheme. The first radio node obtains information about how often one or more radio signals, modulated using the modulation scheme, are used with a transmit modulation quality better than a first threshold. The one or more modulated radio signals are transmitted by the second radio node. The first radio node also selects between the first method and the second method for scaling the transmit power of the one or more radio signals, based on the obtained information.

Description

RADIO NODES AND METHODS THEREIN FOR SELECTING A METHOD FOR SCALING A TRANSMIT POWER AND ADAPTING A RECEIVER CONFIGURATION

TECHNICAL FIELD

The present disclosure relates generally to a first radio node, a second radio node, and methods therein for selecting a method for scaling a transmit power of one or more radio signals transmitted by the second radio node to a third radio node. The present disclosure also relates generally to the third radio node and methods therein for adapting a receiver configuration in the third radio node. The present disclosure relates as well to computer programs and computer-readable storage mediums, having stored thereon the computer programs to carry out the aforementioned methods.

BACKGROUND

Communication devices such as wireless device are also known as e.g. User Equipments (UE), mobile terminals, wireless terminals and/or mobile stations. Terminals are enabled to communicate wirelessly in a cellular communications network or wireless communication system, sometimes also referred to as a cellular radio system or cellular networks. The communication may be performed e.g. between two wireless devices, between a wireless device and a regular telephone and/or between a wireless device and a server via a Radio Access Network (RAN) and possibly one or more core networks, comprised within the cellular communications network.

Wireless devices may further be referred to as mobile telephones, cellular telephones, laptops, or surf plates with wireless capability, just to mention some further examples. The terminals in the present context may be, for example, portable, pocket- storable, hand-held, computer-comprised, or vehicle-mounted mobile devices, enabled to communicate voice and/or data, via the RAN, with another entity, such as another terminal or a server.

The cellular communications network covers a geographical area which is divided into cell areas, wherein each cell area being served by an access node such as a base station, e.g. a Radio Base Station (RBS), which sometimes may be referred to as e.g. "Evolved Node B (eNB)", "eNodeB", "NodeB", "B node", or BTS (Base Transceiver Station), depending on the technology and terminology used. The base stations may be of different classes such as e.g. macro eNodeB, home eNodeB or pico base station, based on transmission power and thereby also cell size. A cell is the geographical area where radio coverage is provided by the base station at a base station site. One base station, situated on the base station site, may serve one or several cells. Further, each base station may support one or several communication technologies. The base stations communicate over the air interface operating on radio frequencies with the terminals within range of the base stations. In the context of this disclosure, the expression

Downlink (DL) is used for the transmission path from the base station to the mobile station. The expression Uplink (UL) is used for the transmission path in the opposite direction i.e. from the mobile station to the base station.

In 3^rd Generation Partnership Project (3GPP) Long Term Evolution (LTE), base stations, which may be referred to as eNodeBs or even eNBs, may be directly connected to one or more core networks.

3GPP LTE radio access standard has been written in order to support high bitrates and low latency both for uplink and downlink traffic. All data transmission is in LTE controlled by the radio base station.

Physical resources in LTE

LTE may use Orthogonal Frequency Division Multiplexing (OFDM) in the DL and

Discrete Fourier Transform (DFT)-spread OFDM in the UL. The basic LTE DL physical resource may thus be seen as a time-frequency grid as illustrated in Figure 1. Figure 1 illustrates the LTE downlink physical resource, where each resource element corresponds to one OFDM subcarrier during one OFDM symbol interval.

In the time domain, LTE DL transmissions may be organized into radio frames of 10 milliseconds (ms), each radio frame consisting of ten equally-sized subframes of length Tsubframe = 1 ms. Figure 2 illustrates the LTE time-domain structure.

Furthermore, the resource allocation in LTE is typically described in terms of Resource Blocks (RB), where a RB corresponds to one slot (0.5 ms) in the time domain, and 12 contiguous subcarriers in the frequency domain. A pair of two adjacent RB in the time direction (1.0 ms) is known as a RB pair. RB are numbered in the frequency domain, starting with 0 from one end of the system bandwidth. DL transmissions may be dynamically scheduled, i.e., in each subframe the Base Station (BS) may transmit control information about which terminals data is transmitted to, and upon which RB the data is transmitted, in the current DL subframe. This control signaling is typically transmitted in the first 1 , 2, 3 or 4 OFDM symbols in each subframe and the number n=1 ,2,3 or 4 is known as the Control Format Indicator (CFI). The DL subframe may also contain common reference symbols, which may be known to the receiver and used for coherent demodulation of, e.g., the control information. A DL system with CFI=3 OFDM symbols as control is illustrated in Figure 3, which represents a DL subframe.

From LTE Re-11 onwards, the above described resource assignments may also be scheduled on the enhanced Physical Downlink Control Channel (EPDCCH). For Rel-8 to Rel-10, only Physical Downlink Control Channel (PDCCH) is available.

Heterogeneous Network and power classes

The heterogeneous network comprises a multilayered deployment of High Power

Nodes (HPNs) such as macro BSs, and Low Power Nodes (LPNs) such as pico BSs. The LPNs and HPNs may operate on the same frequency, a.k.a. co-channel heterogeneous deployment, or on different frequencies, a.k.a. inter-frequency or multi-carrier or multi- frequency heterogeneous deployment. The heterogeneous network deployment may typically be used to offload the HPN by allowing the UEs in the vicinity of LPNs to be served by the LPNs.

The maximum output power of a HPN may, for example, typically be between 43-49 dBm. An example of HPN is a macro node, a.k.a., a wide area base station. Examples of LPNs are a micro node, a.k.a., a medium area BS, a pico node, a.k.a. a local area BS, a femto node, such as a Home Base Station (HBS), relay node etc... The maximum output power of a LPN, for example, may typically be between 20-38 deciBel-milliwatt (dBm), depending upon the power class. For example, a pico node typically may have a maximum output power of 24 dBm, whereas HBS may have a maximum output power of 20 dBm.

The UE power class is generally 23 dBm, i.e., maximum UE power. However, high power UEs, e.g., 30 dBm, may also exist. The combination of HPNs and LPNs may lead to high interference towards the UE served by LPN, especially in a co-channel scenario.

Small cell scenario

With the data services exploding in the future wireless communication networks, small cell deployments may become a dominant trend to improve the network capability and ensure the coverage. Small cells may be deployed both indoor and outdoor, with and without macro coverage. A small cell is served by a LPN.

In most of the popular small cell scenarios, the following characteristics may be observed: small delay spread, low mobility and Doppler shifts, and small number of users in each small cell, etc... These characteristics may bring possibilities for further enhancements in small cell scenarios, such as introduction of higher order modulation, small cell on/off, mobility enhancements, dual connectivity, etc...

The study and specification of small cell enhancements are ongoing in 3GPP Rel- 12. It has been decided that higher order modulation 256 Quadrature Amplitude

Modulation (QAM) will be specified for LTE downlink in Rel-12 to increase spectral efficiency for small cells. In addition, small cell on/off, i.e., small cell is turned on and off based on traffic load increase/decrease, UE arrival/departure, packet call

arrival/completion, will be specified in LTE Rel-12 to mitigate interference and improve energy efficiency in small cell scenarios, as shown in Figure 4. Figure 4 illustrates an example of small cell on/off. Small cell on/off may be characterized by a fast time scale to turn on/off the small cells. The upper graph represents two small cells comprising, respectively, a few UEs and a LPN, which are represented by a small dot with curved lines. The small cells in the upper graph are turned off within a larger cell served by a macro node, represented as a vertical antenna. The lower graph represents the small cells that have been turned on. As may be appreciated in the figure, the number of UEs in the smaller cells is larger than that in the larger cell.

On/Off signal transmission scheme

According to this feature, a.k.a., cell on/off scheme, a cell may be turned on and off where the "on" and "off" occasions occur periodically. Typically, a cell may be considered off if it does not transmit any signal during the entire subframe, otherwise it is considered to be on. Cells operating a cell on/off may transmit discovery signal/s supporting at least cell identification, coarse time/frequency synchronization, intra-frequency/inter- frequency Radio Resource Management (RRM) measurement of cells etc... Examples of

measurements are cell identification, Reference Signal Received Power (RSRP),

Reference Signal Received Quality (RSRQ), path loss, Signal to Interference plus Noise Ratio (SINR), Signal-to-Noise Ratio (SNR), Block Error Rate (BLER), Bit Error Rate (BER) etc. Typically, during an on period, the network node may transmit one or more discovery signals, enabling the UE to do measurements on the cell. The network node may also transmit one or more discovery signals with less frequency during the off period, enabling the UE to do measurements on the cell.

The discovery signal may be any kind of periodic reference signal or pilot signal known to the UE. Examples of discovery signals are Cell specific Reference Signal (CRS), Channel State Information Reference Signal (CSI-RS), Primary Synchronization Signal (PSS), Secondary Synchronization Signal (SSS), Positioning Reference Signal (PRS) etc...

The transmission of the on/off discovery signals may be associated with or characterized by the discovery signal parameters, e.g., a duration of each occasion when a discovery signal is transmitted, periodicity of the occurrence of the occasion of discovery signals, starting time of the occasion or of the pattern of the discovery signal etc... One or more of the discovery signal parameters may be pre-defined and/or signaled to the UE by the network node.

Higher Order Modulation (HOM)

In LTE systems up to Rel-11 , the set of modulation schemes for both DL and UL may include QPSK, 16QAM and 64QAM, corresponding to 2, 4 and 6 bits per modulation symbol, respectively. In LTE evolution, especially for the scenarios with high SINR, e.g., in small cell environments with terminals close to the serving enhanced Node B (eNB), a straightforward means to provide higher data rate with given transmission bandwidths may be the use of HOM, that allows for more bits of information to be carried per modulation symbol. For example, with the introduction of 256QAM, 8 bits may be transmitted per modulation symbol, which may improve the peak data rate maximum by 33% as shown in Figure 5. Figure 5 illustrates the information carried by a symbol, represented as symbol information, in different modulation schemes.

The modulation quality of a modulated signal may be depicted by well-known performance metrics such as Transmission Error Vector Magnitude (Tx EVM), frequency error, time alignment between signals from different antennas etc... These impairments may be induced by the radio transmitter and affect the reception quality at the UE. The Error Vector Magnitude (EVM) is a measure of the difference between the ideal symbols and the measured symbols after the equalization. The EVM result may be typically defined as the square root of the ratio of the mean error vector power to the mean reference power expressed in percent. The EVM may be different for different types of transmitted physical channel, e.g., Physical Downlink Shared Channel (PDSCH), etc . , and physical signals, e.g., CRS etc. The EVM of each E-UTRA carrier for different modulation schemes on PDSCH may not be worse than in table 1 :

Table 1 : EVM requirements

In 3GPP, 256QAM has been studied under the umbrella of small cell enhancements and has been agreed to be standardized in Rel-12.

It should be noted that 256QAM may only provide gains when the SINR is sufficiently high in certain scenarios. In practice, the performance of 256QAM may be highly sensitive to Tx EVM and Reception (Rx) impairments, which effectively may act as an interference floor, regardless of the SINR of the radio environment, and hence may become the primary limiting aspect of high order modulations.

Hence, while it has been decided that higher order modulation 256 Quadrature

Amplitude Modulation (QAM) will be specified to increase spectral efficiency for small cells, addressing the Tx EVM and Reception (Rx) sensitivity associated with the 256QAM modulation may result in reduced coverage and degradation of the whole system performance. SUMMARY

It is an object of embodiments herein to improve the performance in a wireless communications network by providing an improved way for radio nodes to transmit radio signals.

According to a first aspect of embodiments herein, the object is achieved by a method performed by a first radio node. The method is for selecting a method for scaling a transmit power of one or more radio signals transmitted by a second radio node to a third radio node. The second radio node uses a modulation scheme. The first radio node obtains information about how often one or more radio signals modulated using the modulation scheme, are used with a transmit modulation quality better than a first threshold. The one or more modulated radio signals are transmitted by the second radio node. The first radio node also selects between a first method and a second method for scaling the transmit power of the one or more radio signals, based on the obtained information.

According to a second aspect of embodiments herein, the object is achieved by a method performed by the second radio node. The method is for selecting the method for scaling the transmit power of the one or more radio signals transmitted by the second radio node to the third radio node. The second radio node uses the modulation scheme. The second radio node receives the message from the first radio node. The message comprises an indication of the selected method between the first method and the second method for scaling the transmit power of the one or more radio signals. The selected method is selected based on information about how often the one or more radio signals, modulated using the modulation scheme, are used with a transmit modulation quality better than the first threshold. The one or more modulated radio signals are transmitted by the second radio node. The information is obtained by the first radio node. The second radio node selects between the first method and the second method for scaling the transmit power of the one or more radio signals, based on the received message.

According to a third aspect of embodiments herein, the object is achieved by a method in the third radio node for adapting a receiver configuration in the third radio node.

The third radio node receives the message from the first radio node. The message comprises the indication of the selected method between the first method and the second method for scaling the transmit power of the one or more radio signals transmitted by the second radio node. The second radio node uses the modulation scheme. The selected method has been selected based on information about how often the one or more radio signals, modulated using the modulation scheme, are used with a transmit modulation quality better than the first threshold. The one or more modulated radio signals are transmitted by the second radio node, and the information is obtained by the first radio node. The third radio node adapts the receiver configuration in the third radio node, based on the received message.

According to a fourth aspect of embodiments herein, the object is achieved by the first radio node. The first radio node is configured to select the method for scaling the transmit power of the one or more radio signals configured to be transmitted by the second radio node to the third radio node. The second radio node is configured to use the modulation scheme. The first radio node is configured to obtain information about how often one or more radio signals, modulated using the modulation scheme, are used with the transmit modulation quality better than the first threshold. The one or more modulated radio signals are configured to be transmitted by the second radio node. The first radio node is further configured to select between the first method and the second method for scaling the transmit power of the one or more radio signals, based on the obtained information.

According to a fifth aspect of embodiments herein, the object is achieved by the second radio node. The second radio node is configured to select the method for scaling the transmit power of the one or more radio signals configured to be transmitted by the second radio node to the third radio node. The second radio node is configured to use the modulation scheme. The second radio node is configured to receive the message from the first radio node configured to operate in the wireless communications network. The message comprises the indication of the selected method between the first method and the second method for scaling the transmit power of the one or more radio signals. The one or more radio signals are modulated using the modulation scheme. This is done based on information about how often the one or more modulated radio signals are used with the transmit modulation quality better than the first threshold. The one or more modulated radio signals are configured to be transmitted by the second radio node. The information is configured to be obtained by the first radio node. The second radio node is further configured to select between the first method and the second method for scaling the transmit power of the one or more radio signals. This is done based on the received message.

According to a sixth aspect of embodiments herein, the object is achieved by the third radio node, configured to adapt the receiver configuration in the third radio node. The third radio node is configured to receive the message from the first radio node. The message comprises the indication of the selected method between the first method and the second method for scaling the transmit power of the one or more radio signals. The one or more radio signals are configured to be transmitted by the second radio node. The second radio node is configured to use the modulation scheme. The selected method has been selected based on information about how often the one or more radio signals, modulated using the modulation scheme, are used with the transmit modulation quality better than the first threshold. The one or more modulated radio signals are configured to be transmitted by the second radio node. The information is configured to be obtained by the first radio node. The third radio node is further configured to adapt the receiver configuration in the third radio node, based on the received message.

According to a seventh aspect of embodiments herein, the object is achieved by a computer program, comprising instructions which, when executed on at least one processor, cause the at least one processor to carry out the method performed by the first radio node.

According to a sixth aspect of embodiments herein, the object is achieved by a computer-readable storage medium, having stored thereon the computer program, comprising instructions which, when executed on at least one processor, cause the at least one processor to carry out the method performed by the first radio node.

According to a seventh aspect of embodiments herein, the object is achieved by a computer program, comprising instructions which, when executed on at least one processor, cause the at least one processor to carry out the method performed by the second radio node.

According to an eighth aspect of embodiments herein, the object is achieved by a computer-readable storage medium, having stored thereon the computer program, comprising instructions which, when executed on at least one processor, cause the at least one processor to carry out the method performed by the second radio node.

According to a seventh aspect of embodiments herein, the object is achieved by a computer program, comprising instructions which, when executed on at least one processor, cause the at least one processor to carry out the method performed by the third radio node.

According to an eighth aspect of embodiments herein, the object is achieved by a computer-readable storage medium, having stored thereon the computer program, comprising instructions which, when executed on at least one processor, cause the at least one processor to carry out the method performed by the third radio node.

By selecting between the first method and the second method for scaling the transmit power of the one or more radio signals, based on the obtained information, the first network node enables an appropriate power scaling at the transmitting radio node, e.g., the first radio node in some embodiments, or the second radio node. In this way, the first radio node may facilitate the usage of the better modulation quality, e.g., higher order modulation, while maintaining the performance of the wireless communications network. The fact that the method of power scaling at the transmitting radio node is not always the same enables the first radio node to, if needed, choose a method, e.g., the second method, wherein only the power of radio signals not affecting radio coverage may be scaled back, which facilitates a better modulation quality.

The first radio node may also avoid fluctuation in cell coverage by avoiding scaling back the power of radio signals associated with the radio coverage, e.g., cell specific reference signals. The first radio node may as well ensure better cell coverage and allow more power for control signals. By avoiding fluctuation in cell coverage, the first radio node may also prevent an unnecessary increase in cell load in a macro cell, such as a first cell, served by a HPN, such as the first network node. This may enhance the ability of the macro cell, such as the first cell, to serve users which may not be offloaded to small cells e.g. pico or micro cells.

Further advantages of some embodiments disclosed herein are discussed below. BRIEF DESCRIPTION OF THE DRAWINGS

Examples of embodiments herein are described in more detail with reference to attached drawings in which:

Figure 1 is a schematic diagram illustrating the LTE DL physical resource.

Figure 2 is a schematic diagram illustrating the LTE time-domain structure.

Figure 3 is a schematic diagram illustrating a DL subframe.

Figure 4 is a schematic diagram illustrating a small cell on/off.

Figure 5 is a schematic diagram illustrating symbol information of different modulation schemes.

Figure 6 is a schematic block diagram illustrating embodiments in a wireless

communications network, according to embodiments herein.

Figure 7 is a flowchart depicting embodiments of a method in a first radio node,

according to embodiments herein.

Figure 8 is a flowchart depicting embodiments of a method in a first radio node,

according to embodiments herein.

Figure 9 is a flowchart depicting embodiments of a method in a second radio node, according to embodiments herein.

Figure 10 is a flowchart depicting embodiments of a method in a third radio node,

according to embodiments herein.

Figure 1 1 is a flowchart depicting embodiments of a method in a third radio node,

according to embodiments herein.

Figure 12 is a schematic block diagram illustrating embodiments of a first radio node, according to embodiments herein.

Figure 13 is a schematic block diagram illustrating embodiments of a second radio node, according to embodiments herein.

Figure 14 is a schematic block diagram illustrating embodiments of a third radio node, according to embodiments herein. DETAILED DESCRIPTION

As part of developing embodiments herein, one or more problems that may be associated with use of at least some existing methods, and that may addressed by embodiments herein, will first be identified and discussed.

HOM have stringent requirements on transmit modulation quality, e.g. EVM, and transmit power. For example, typically, for using 256QAM in the DL, the EVM of the transmitted radio signal may have to be maintained below 4% by the radio transmitter to ensure acceptable quality at the receiver. This may require reduction of transmit power, leading to coverage loss and may also cause handover of users to another cell, e.g., from a pico cell to a macro cell. This in turn may also increase load in the neighboring cells, e.g., a macro cell. Embodiments herein disclose different approaches that may ensure a reasonable compromise between coverage loss and efficient use of HOM.

To implement higher order modulation in small cell scenarios, it may be of great importance to reduce the Tx EVM in order to get robust performance through 256QAM. One approach may be to use better Power Amplifier (PA) components to achieve a better linearity at the transmitter. However, this approach may significantly increase the cost and size of the radio node, e.g., base station, wireless device etc... , and, hence, may not be desirable in small cell scenarios, where there may be large scale deployments of small cell nodes. Another option to reduce the EVM may be to use power back-off at the transmitter, a.k.a., power reduction or maximum power reduction. In this case, the maximum transmit power of the BS is reduced by some margin, e.g., 2-5 dB. It has been shown that with a few dB transmit power back-off, the EVM may be effectively decreased. However, this approach comes at the cost of reduced coverage. Moreover, power back-off in small cells adversely affects the macro off-loading. In other words, by reducing the transmitter power in small cells, more UEs may end up being connected to the macro cell. The cell load in the macro may increase, which may then degrade the whole system performance. More importantly, in case the power back-off is done dynamically to cope with different scenarios, the cell coverage, e.g., CRS, PSS/SSS, Physical Broadcast Channel (PBCH), etc... , may be fluctuated, which may affect performance of the network.

One approach proposed to address the macro off-loading problem due to power back-off is to use biased cell range extension. In this case, an offset is transmitted to the UE. The UE may apply the offset to the DL measurement, allowing the UE to stay connected to the small cell for longer time and avoid being connected to, i.e. handover, to the macro-cell. However, this solution may not be able to cope with cell coverage fluctuation, and hence, it may not be desirable.

Embodiments will now be described more fully hereinafter with reference to the accompanying drawings, in which examples of the claimed subject matter are shown. The claimed subject matter may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the claimed subject matter to those skilled in the art. It should also be noted that these embodiments are not mutually exclusive. Components from one embodiment may be tacitly assumed to be present/used in another embodiment.

Figure 6 depicts a particular example of a wireless communications network 600, sometimes also referred to as a cellular radio system, cellular network or wireless communications system, in which embodiments herein may be implemented. The wireless communications network 600 may for example be a network such as a Long-Term

Evolution (LTE), e.g. LTE Frequency Division Duplex (FDD), LTE Time Division Duplex (TDD), LTE Half-Duplex Frequency Division Duplex (HD-FDD), LTE operating in an unlicensed band, Wideband Code Division Multiple Access (WCDMA), Universal

Terrestrial Radio Access (UTRA) TDD, Global System for Mobile communications (GSM) network, GSM/Enhanced Data Rate for GSM Evolution (EDGE) Radio Access Network (GERAN) network, Ultra-Mobile Broadband (UMB), EDGE network, network comprising of any combination of Radio Access Technologies (RATs) such as e.g. Multi-Standard

Radio (MSR) base stations, multi-RAT base stations etc., any 3rd Generation Partnership Project (3GPP) cellular network, WiFi networks, Worldwide Interoperability for Microwave Access (WMax), 5G system or any cellular network or system.

The wireless communications network 600 comprises a first network node 611 , and a second network node 612. Each of the first network node 61 1 and the second network node 612 may be, for example, a base station such as e.g., an eNB, eNodeB, or a Home Node B, a Home eNode B, femto Base Station, BS, pico BS, Transmission Point (TP), or any other network unit capable to serve a wireless device or a machine type communication device in the wireless communications network 600. In some particular embodiments, the first network node 61 1 and the second network node 612 may be a stationary relay node or a mobile relay node.

The wireless communications network 600 covers a geographical area which is divided into cell areas, wherein each cell area is served by a network node, although, one network node may serve one or several cells. In the non-limiting example depicted in Figure 6, the first network node 61 1 serves a first cell 621 , and the second network node 612 serves a second cell 622. Each of the first network node 61 1 and the second network node 612 may be of different classes, such as, e.g., macro eNodeB, home eNodeB or pico base station, based on transmission power and thereby also cell size. Typically, the wireless communications network 600 may comprise more cells similar to the first cell 621 and the second cell 622, served by their respective network node. This is not depicted in Figure 6 for the sake of simplicity. Each of the first network node 611 and the second network node 612 may support one or several communication technologies, and its name may depend on the technology and terminology used. The first network node 61 1 may communicate with the second network node 612 over a first link 631 and/or a first radio link 632.

In WCDMA, the first network node 61 1 and the second network node 612, which may be referred to as NodeBs or even NBs, may be directly connected to a controller network node 640. The controller network node 640 may be for example, a network controller such as Radio Network Controller (RNC), Base Station Controller (BSC), or master base station. The controller network node 640 may in turn be connected to one or more central network nodes 650. The one or more central network nodes 650 may be for example, a Mobility Management Entity (MME), an Operational and Maintenance (O&M), an Operational Support System (OSS) or a Self Organizing Network (SON).

The first network node 61 1 and the second network node 612 may communicate with the controller network node 640 over a second link 661 and over a third link 662, respectively. In some particular embodiments, any of the first network node 611 and the second network node 612 may be the same, i.e., they may be co-located.

A number of wireless devices are located in the wireless communications network 600. In the example scenario of Figure 6, only two wireless devices are shown, a first wireless device 671 , and a second wireless device 672. Any of the first wireless device 671 and the second wireless device 672 may also be referred to herein as "a wireless device 671 , 672". Each of the first wireless device 671 and the second wireless device 672 is a wireless communication device or radio communication device such as a UE, which is also known as e.g., mobile terminal, wireless terminal, mobile station, mobile telephone, cellular telephone, smart phone, and/or target device. Further examples of different wireless devices include laptops with wireless capability, Laptop Embedded Equipment (LEE), Laptop Mounted Equipment (LME), USB dongles, Customer Premises Equipment (CPE), modems, Personal Digital Assistants (PDA), or tablet computers, sometimes referred to as a surf plates with wireless capability or simply, tablets, Machine- to-Machine (M2M) capable devices or UEs, device to device (D2D) UE or wireless devices, devices equipped with a wireless interface, such as a printer or a file storage device, Machine Type Communication (MTC) devices such as sensors, e.g., a sensor equipped with UE, just to mention some examples.

Each of the devices is wireless, i.e., it is enabled to communicate, e.g., voice and/or data, wirelessly in the wireless communications network 600. The communication may be performed e.g., between two devices, such as between the first wireless device 671 and the second wireless device 672, as described above, between a device and a regular telephone and/or between a device and another entity, such as a server or any other radio network unit capable of communicating over a radio link in the wireless communications network 600. The communication may be performed e.g., via a RAN.

The first wireless device 671 is located within the first cell 621. The first wireless device 671 is configured to communicate within the wireless communications network 600 via the first network node 61 1 over a second radio link 681 when the first wireless device 671 is present in the first cell 621 served by the first network node 61 1. In this example, the second wireless device 672 is also located within the first cell 621. However, in other embodiments, the second wireless device 672 may be located within the radio coverage of the first wireless device 671 , in another cell which is adjacent to the first cell 621. When the second wireless device 672 is present in the first cell 621 , it is configured to communicate within the wireless communications network 600 via the first network node 61 1 over a radio link such as e.g. a third radio link 682. When the second wireless device 672 is present in another cell, e.g., the second cell 622, it is configured to communicate within the wireless communications network 600 via another network node serving the another cell, such as the second network node 612 over another radio link similar the second radio link 682.

The first wireless device 671 is capable of communicating with other wireless devices using wireless D2D communication, such as the second wireless device 672, over a D2D link 690. The second wireless device 672 is capable of communicating with other wireless devices using wireless D2D communication, such as the first wireless device 671 , over a D2D link such as the D2D link 690, in the case of the first wireless device 671 , or a similar D2D link.

In some embodiments, the non-limiting term UE is used. The UE herein may be any type of wireless device, such as the first wireless device 671 , capable of communicating with a network node, such as the first network node 61 1 , or another UE, such as the second wireless device 672, over radio signals.

Also in some embodiments, generic terminology, "radio network node" or simply "network node (NW node)", may be used. It may be any kind of network node which may comprise, e.g., a base station, radio base station, base transceiver station, evolved Node B (eNB), Node B, relay node, access point, radio access point, Remote Radio Unit (RRU) Remote Radio Head (RRH) etc, any of which are such as the first network node 611 , or e.g., base station controller, network controller, radio network controller, any of which are such as the controller network node 640, or even for example a core network node, such as MME, O&M, OSS or SON, such as the one or more central network nodes 650. In some embodiments another generic terminology, "node" or radio node is used. A node or radio node herein may be a network node or a UE. The node may be a transmitting node, which transmits signals or a receiving node, which receives signals. Thus, any of the first network node 61 1 , the controller network node 640, the one or more central network nodes 650, and the first wireless device 671 may be referred to herein as a first radio node 611 , 640, 650, 671. In the embodiments wherein the first radio node 61 1 , 640, 650, 671 is one of the first network node 61 1 or the first wireless device 671 , the first radio node 61 1 , 671 may also be referred to herein as a "transmitting radio node" or a "transmitting node".

Any of the first network node 61 1 , the second network node 612, the first wireless device 671 , and the second wireless device 672 may be referred to herein as a second radio node 611 , 612, 671 , 672. The second radio node 611 , 612, 671 , 672 may also be referred to herein as a "transmitting radio node" or a "transmitting node". In some particular embodiments, the first radio node 61 1 , 671 is the same as the second radio node 611 , 671. Any of the first network node 611 , the second network node 612, the first wireless device 671 , and the second wireless device 672 may be referred to herein as a third radio node 611 , 612, 671 , 672. The third radio node 61 1 , 612, 671 , 672 may also be referred to herein as a "receiving radio node" or a "receiving node". Any of the first network node 611 , the second network node 612, the controller network node 640, and the one or more central network nodes 650, or any other network node with similar characteristics, may be referred to herein as another network node 611 , 612, 640, 650. The first network node 61 1 , or any network node with similar characteristics, may also be referred to herein as a radio network node 611. Thus, for example, in some embodiments, the first radio node may be the controller network node 640, the second radio node may be the first network node 611 , and the third radio node may be the first wireless device 671.

In another example embodiment, the first radio node may be the first network node 611 , the second radio node may also be the first network node 61 1 , and the third radio node may be the first wireless device 671 , or the second network node 612, and so and so forth.

The embodiments herein are described by considering LTE. However, the embodiments may be applicable to any RAT or multi-RAT systems, where a UE, such as the first wireless device 671 , regularly assesses the serving cell, such as the first cell 621 , performance by the virtue of Radio Link Monitoring (RLM) procedure, or equivalent procedures, e.g., LTE FDD/TDD, WCDMA/ High Speed Packet Access (HSPA),

GSM/GERAN, Wi Fi, Code Division Multiple Access 2000 (CDMA2000) etc... LTE or LTE- Advanced terminology may sometimes be used throughout to describe embodiments herein, however, the concepts described herein are not limited to LTE or LTE-Advanced. Rather, the concepts disclosed herein may be applicable to any suitable type of cellular communications network. The embodiments herein are described for a single carrier, a.k.a., a single carrier operation of the UE, such as the first wireless device 671 , in a network node, such as the first network node 611. However, the embodiments may be applicable for multi-carrier or carrier aggregation operation, i.e., when a network node, such as the first network node 611 , transmits a plurality of carriers to the same or different UEs, such as the first wireless device 671 and the second wireless device 672. The embodiments may apply to each carrier in this case.

Embodiments herein may be understood as concerning methods of adaptive scaling of Tx power, in relation to the HOM needs of a transmitting node.

Embodiments herein may comprise methods in the first radio node 61 1 , 640, 650,

671. The first radio node 61 1 , 640, 650, 671 , may determine a frequency of using radio signals of a transmitting node, such as the second radio node 61 1 , 612, 671 , 672, with a higher modulation quality, that is, a modulation quality better than a threshold, e.g., a first threshold. This may provide the first network node 611 , 640, 650, 671 with a notion of the HOM needs the transmitting node has. Then, it may select a power scaling method for transmission of the radio signals for the transmitting node, depending upon the determined frequency of usage of the signals with transmit modulation quality better than the first threshold. This selection may be done so that, the transmit power is scaled to adapt to the needs for HOM of the node transmitting the signals, while the coverage of the cell may be retained. For example, if the transmitting node has a high need for HOM, the scaling of the transmit power may be done so that, by scaling back the power of e.g. data signals, EVM may be kept at a level that guarantees a robust performance through e.g., 256QAM. The coverage of the cell may be retained by not scaling back, or not scaling back to the same degree, the transmit power of e.g., common channels. That is, if the frequency of using a higher modulation quality is determined to be high, the first radio node 61 1 , 640, 650, 671 , may select a method, of unequal power scaling, wherein the transmit power of signals to be transmitted by the transmitting node, such as the second radio node 61 1 , 612, 671 , 672 is scaled differently, depending on the type of signals transmitted. Otherwise, a method of equal power scaling, may be adopted for transmit power scaling of signals to be transmitted by the transmitting node. In this way, when HOM is used more frequently, the power of common channels e.g., CRS, PSS/SSS, PBCH etc., which may determine cell coverage, may be retained. This may ensure consistent coverage of the cell and may avoid unnecessary cell change by the UEs, such as the first wireless device 671 and the second wireless device 672.

Embodiments herein may also comprise a method in the receiving node of the signals transmitted by the second radio node 61 1 , 612, 671 , 672. The receiving node, such as the third radio node 611 , 612, 671 , 672, may also be informed about the power scaling method used by the second radio node 61 1 , 612, 671 , 672. The receiving node may then adapt its receiver configuration accordingly and may use it for receiving signals, such as the scaled radio signals, from the transmitting node.

Embodiments of a method performed by the first radio node 611 , 640, 650, 671 for selecting a method for scaling a transmit power of one or more radio signals transmitted by the second radio node 61 1 , 612, 671 , 672 to the third radio node 611 , 612, 671 , 672, will now be described with reference to the flowchart depicted in Figure 7. As stated earlier, the first radio node 61 1 , 640, 650, 671 , the second radio node 611 , 612, 671 , 672, and the third radio node 611 , 612, 671 , 672 operate in the wireless communications network 600. The second radio node uses a modulation scheme, e.g., a HOM.

Figure 7 depicts a flowchart of the actions that are or may be performed by the first radio node 61 1 , 640, 650, 671 in embodiments herein. In the Figure, a box with dashed lines indicates that the action is optional.

The method for selecting may comprise the following actions, which actions may as well be carried out in another suitable order than that described below. In some embodiments, all the actions may be carried out, whereas in other embodiments only some action/s may be carried out.

As mentioned above, the first radio node 611 , 640, 650, 671 may be one or several radio nodes. Some examples applying to the description below are that: in some embodiments, the first radio node 611 , 671 is the same as the second radio node 61 1 , 671 ; in some embodiments, the first radio node 611 , 640, 650, 671 is the first radio network node 61 1 ; in some embodiments, the first radio node 671 is the first wireless device 671 and the third radio node 611 , 672 is the first, radio, network node 611 or the second wireless device 672; in some embodiments, the first radio node 61 1 is the first network node 611 and the third radio node 612 is the second network node 612.

Action 701

In order to select a transmit power scaling method for the second radio node 611 , 612, 671 , 672 that is adapted to the needs for HOM of the second radio node 61 1 , 612, 671 , 672, the first radio node 611 , 640, 650, 671 may first ascertain what are the needs for HOM of the second radio node 611 , 612, 671 , 672. For that purpose, in this action, the first radio node 611 , 640, 650, 671 may obtain information about how often one or more radio signals transmitted by the second radio node 611 , 612, 671 , 672 are used with a higher transmit modulation quality. Here, higher is a relative term that is determined by whether the modulation quality is higher, or lower, than a first threshold, e.g. a number, as described later. That is, in this action, the first radio node 611 , 640, 650, 671 obtains information about how often, i.e., the frequency with which, one or more radio signals, modulated using the modulation scheme, are used with a transmit modulation quality better than the first threshold, the one or more modulated radio signals being transmitted by the second radio node 61 1 , 612, 671 , 672. The one or more radio signals

The signal herein, e.g., the one or more modulated radio signals, may be a UL signal, if the transmitting node is a UE, such as the first wireless device 671. The signal herein may be a DL signal if the transmitting node is a network node, e.g., a BS, access point, RRH etc... , such as the first network node 61 1.

The DL signals may be any of DL physical signals and/or DL physical channels.

Examples of DL physical signals in LTE are Reference signals (RS), Multimedia

Broadcast Single Frequency Network (MBSFN) RS, Demodulation Reference Signal (DMRS), PSS, SSS, CRS, CSI-RS and PRS. Examples of DL physical channels in LTE are PDSCH, Physical Downlink Control Channel (PDCCH), Physical Control format Indicator Channel (PCFICH), Physical Hybrid Automatic Repeat reQuest (ARQ) Indicator CHannel (PHICH) or Enhanced Physical Downlink Control CHannel (E-PDCCH).

The UL signals may be any of UL physical signals and/or UL physical channels. Examples of UL physical signals in LTE are DMRS and Sounding Reference Signals (SRS). Examples of UL physical channels in LTE are Physical Uplink Shared CHannel (PUSCH) and Physical Uplink Control CHannel (PUCCH).

The transmit modulation quality and the first threshold

In terms of what may be understood by the transmit modulation quality with which the one or more radio signals are used, in some embodiments, the transmit modulation quality of the one or more modulated radio signals is at least one of: an EVM, a frequency error and a Time Alignment Error (TAE) between signals from any two pair of transmit antennas. The frequency error may be understood as the measure of the difference between the actual frequency of a signal transmitted by a radio node and the frequency assigned or allocated to the radio node transmitting the signal. The TAE may be understood as the largest timing difference between any two signals of any two pair of transmit antennas. In one example, the modulation quality, e.g., the transmit modulation quality, may be expressed in terms of EVM requirement of a modulated radio signal, e.g., PDSCH in DL. In this manner, the modulation quality better than a threshold, e.g., the first threshold, may mean the modulated radio signal with an EVM requirement less than a predetermined threshold, i.e., EVM < x%, with x% being the first threshold in this example. That is, the fact that the modulation quality is "better" than a first threshold does not necessarily mean that is higher than the threshold. This is because the higher the modulation quality, the lower the EVM requirement may be, as explained earlier. The frequency of using a modulated radio signal with EVM < x% may be determined by the transmitting node itself or based on input received from another node, e.g., the another network node 61 1 , 612, 640, 650. For example, if the transmitting node is a network node, such as the first network node 611 , then it may determine the frequency of usage itself. But if the transmitting node is a UE, such as the first wireless device 671 , then it may determine the frequency of usage itself, or by a network node, such as the first network node 611 , or by both, i.e, UE and network node.

Thus, in some embodiments, obtaining comprises one of: determining the information autonomously, and receiving the information, e.g., from another node. In another example, the modulated signal, e.g., the one or more modulated radio signals, is a radio signal modulated using an HOM, where HOM may comprise M- modulated symbols, a.k.a., M-modulated alphabets, of a radio signal with M above a threshold N. Each of M and N may represent a number, and N is another example of the first threshold. The frequency of using a HOM with M > N may be determined by the network node, such as the first network node 611. For example, if N is set to be 128 symbols, then the HOM may be 256 QAM with M = 2^K, where K = 8 is the number of bits representing each of the 256 modulated symbols. A typical value of x, as described above, may be between 3-4% for 256 QAM. The HOM of 256 QAM may in particular be used in the transmitting node which is a network node, such as the first network node 611.

In a further example, modulation quality is expressed both in terms of EVM requirement and the number of modulated symbols M of a modulated radio signal. The node, e.g., the first radio node 61 1 , 640, 650, 671 , may determine the frequency of using the modulated signal with EVM < x% and using a HOM with the number of modulated symbols M > N. According to the foregoing, in some embodiments, the one or more modulated radio signals are modulated using a number of modulated symbols.

In some embodiments, the one or more modulated radio signals are modulated using HOM, which satisfies a condition that the number of modulated symbols is above a second threshold, that is another number or value. In some instances wherein the first threshold is N, the first threshold may be the same as the second threshold.

In some of these embodiments, the HOM is 256 QAM, the number of modulated symbols is 256 and the second threshold is 128 symbols. In some embodiments, the HOM may be 512 QAM, the number of modulated symbols may be 512, and the second threshold may be 256 symbols. Yet in some embodiments, the HOM may be 1024 QAM, the number of modulated symbols may be 1024 and the second threshold may be 256 symbols.

In some embodiments, the first threshold is determined by the first radio node 61 1 , 640, 650, 671 autonomously or based on input received from another network node 612, 640, 650.

Information about how often the one or more radio signals are used with a transmit modulation quality better than the first threshold

The frequency of using or expected to use a better modulation quality than a threshold, e.g., the information about how often the one or more modulated radio signals are used with the transmit modulation quality better than the first threshold, may be determined based on statistics and/or estimated through other manners. In one example, it is done at the network node, such as the first network node 611 , or it may be done at the UE, such as the first wireless device 671 , or in both nodes, based on one or more of the following criteria: a) Statistics of using a better modulation quality The historical information of using a better modulation quality, that is a modulation quality of a certain value, e.g. , 256QAM, is stored in the network node, such as the first network node 61 1 , based on their usage during the previous transmissions. These statistics are collected at the node, e.g. , the first radio node 61 1 , 640, 650, 671 , and then applied directly when determining the frequency of using a better modulation quality. For example, the node being a network node, such as the first network node 61 1 , may set up a counter to save the information of using different modulation schemes in DL for all UEs, such as the first wireless device 671 and the second wireless device 672, and then the frequency of using, e.g. 256QAM, may be easily obtained based on these counter values. The information may be collected at every transmission, e.g. , in every subframe. The information may be collected for transmissions to or from one or a plurality of UEs. The information may be collected for a particular type of signals, e.g. , PDSCH, or for several types of signals. The statistics may be collected for a certain period of time, e.g., 30 seconds, to ensure the results are reliable. The node, e.g. , the first radio node 61 1 , 640, 650, 671 , may also decide to use them for determining the frequency of their usage provided the number of usage of certain type of modulation is above a threshold, such as the first threshold, e.g. , 500 times or in 500 subframes over the last 10 seconds. If the percentage of using a better modulation, e.g., 256QAM, is above the threshold, e.g. 20%, the node determines the frequency to be high, and to be low otherwise. b) Amount of data in buffer

If the amount of data in buffer in the node for transmission, e.g. , the first radio node 61 1 , 671 in some embodiments, to a receiver, such as the third radio node 61 1 , 612, 671 , 672, is continuously high, e.g. , higher than a predetermined value, e.g., more than 70% occupancy, for a predetermined period at the transmitting node, then the node, e.g. , the first radio node 61 1 , 640, 650, 671 , may estimate that the frequency of using a better modulation quality is high. Otherwise, the node, e.g. , the first radio node 61 1 , 640, 650, 671 , may determine the frequency to be low. This is because more data in the buffer may require the node to transmit at a higher data rate by using higher order modulation. c) Operation of cell on/off scheme When a cell on/off scheme is operating in neighboring cells, the interference may be potentially low and hence, the possibility to schedule a signal with a better modulation quality is high. Then, the node, e.g., the first radio node 61 1 , 640, 650, 671 , may estimate that the frequency of using a better modulation quality is high. Otherwise, the frequency may be low. The node, e.g., the first radio node 61 1 , 640, 650, 671 , may determine if the cell on/off scheme is used based on one or more of the following: historical information of using on/off scheme used by the node itself or in neighboring nodes, such as the second network node 612, input received from another node that on/off scheme is used, e.g., a network node receiving information from neighboring network node, or a UE receiving information from its serving network node. d) Cell deployment

If the node, e.g., the first radio node 611 , 671 in some embodiments, is deployed or operating in an indoor environment with isolation of interference and good radio environment, the node, e.g., the first radio node 611 , 640, 650, 671 , may assume that the frequency of using a better modulation quality is high. Otherwise, the frequency of usage may be assumed to be low. e) UE category/capability

This applies when the node is a network node, such as the first network node 611 or the controller network node 640, or the one or more central network nodes 650. Each camping UE, such as the first wireless device 671 , may report the UE category and capability to the serving network node, such as the first network node 611. Then, the network node, e.g., the first network node 611 , the controller network node 640, or the one or more central network nodes 650, may collect the information and may determine the frequency of using a better modulation quality. In one example, if the number and/or percentage of UEs, or wireless devices, with the capability to support better modulation quality are below a threshold, the network node e.g., the first network node 611 , the controller network node 640, or the one or more central network nodes 650, may determine that the frequency is low. For example, if there is no UE, i.e., wireless device, in the cell, such as the first cell 621 , with capability to support HOM, the frequency of using a better modulation quality may be determined to be very low. It may be noted that the node, e.g. , the first radio node 61 1 , 671 in some

embodiments, may make a determination based on one or more of above factors. For example, the node may determine the frequency of using a better modulation is high when the statistics shows high probability of using HOM and the percentage of HOM-capable UEs camped in the cell is high. Otherwise, the frequency is determined to be low.

In case the transmitting node is a UE, such as the first wireless device 671 , and the determination is done by the network node, e.g. , the first network node 61 1 , the controller network node 640, or the one or more central network nodes 650, then the network node may configure the UE with the information related to the determined frequency of using a better modulation for transmitting UL signals. The U E may use this information for selecting a power scaling method for scaling power of transmit signals as described below. The UE may also take into account its own determination to select the power scaling method, as will be described later. The information obtained by the first radio node 61 1 , 640, 650, 671 in this action 201 may refer to any of the variables mentioned above, pertaining to the modulation quality, such as EVM, the number of modulated symbols, e.g. "M", any variables pertaining to a)- e) above, etc... Thus, according to the foregoing, in some embodiments, the information is based on at least one of: statistics of usage by the first radio node 61 1 , 640, 650, 671 of a better modulation quality, an amount of data in a buffer for transmission of the first radio node 61 1 , 640, 671 , an operation of a cell on/off scheme in neighboring cells to the first radio node 61 1 , 640, 671 , a cell deployment of the first radio node 61 1 , 640, 671 , and a category or capability of a receiving wireless device 671 , 672.

Further description about this action may be found below under the heading

"Determination of frequency, e.g. , information about how often, of transmitting signals, e.g., one or more modulated radio signals, with higher modulation quality, e.g., a transmit modulation quality better than the first threshold".

Action 702

Referring again to Figure 7, once the first radio node 61 1 , 640, 650, 671 has found how often the one or more modulated radio signals are transmitted with the higher modulation quality, the first radio node 61 1 , 640, 650, 671 may be in a position to select a method for scaling the transmit power of the radio signals, adapted to the higher modulation quality needs of the transmitting node, but retaining coverage. Thus, in this action, the first radio node 611 , 640, 650, 671 selects between a first method and a second method for scaling the transmit power of the one or more radio signals, based on the obtained information. The one or more radio signals may be transmitted by the second radio node 611 , 612, 671 , 672.

The node, e.g., the first radio node 611 , 640, 650, 671 , may select one of the two methods of power scaling for scaling the transmit power of signals to be transmitted depending upon the determined frequency of usage of the signals with transmit modulation quality better than a threshold, e.g. the first threshold. More specifically, the node may select one of the two methods of power scaling for scaling the transmit power of signals to be transmitted, wherein the selection of the said method may depend upon the frequency with which certain modulation with M modulated symbols > threshold, e.g., M = 128 symbols, is used or is expected to be used for transmitting signals. The two power scaling methods, described below, may be pre-defined.

As an example, if the frequency of using a better modulation quality than threshold is determined to be high, for example, the percentage of using HOM such as 256 QAM is higher than a threshold, then the node, e.g., the first radio node 61 1 , 640, 650, 671 , may select a method 2, characterized by unequal power scaling as described below, for scaling the transmit power of signals to be transmitted by a transmitting node, such as the second radio node 611 , 612, 671 , 672. Otherwise, method 1 , characterized by equal power scaling as described below, may be adopted for transmit power scaling of signals to be transmitted by a transmitting node, such as the second radio node 61 1 , 612, 671 , 672. In this way, when HOM is used more frequently, the power of common channels (e.g., CRS, PSS/SSS, PBCH etc.) which may determine cell coverage, may be retained.

This may ensure consistent coverage of the cell, e.g., the first cell 621 when the second radio node is the first network node 61 1 , and may avoid unnecessary cell change by the UEs, such as the first wireless device 671 and the second wireless device 672.

In one example, the two methods are defined below:

· Method 1 : Equal power scaling: This method may also be interchangeably called linear power scaling. This method may scale the transmit power of all radio resources of transmitting signals, e.g., Resource Element (RE), RB, physical RB, physical channel, channelization code etc... , transmitted by a radio transmitting node, such as the second radio node 61 1 , 612, 671 , 672, e.g. , all signals transmitted in a cell during certain time period and over certain bandwidth, by the same amount, e.g., x dB, compared to a reference transmit power value. Examples of reference value is the maximum power, pre- defined power level, power level in the previous transmission or maximum power of certain power class of UE, such as the first wireless device 671 , or BS, such as the first network node 61 1 . For example, a transmitting node, such as the second radio node 61 1 , 612, 671 , 672, may decrease or reduce the transmit power by 2 dB, in log scale, compared to a reference value in all REs over the entire Bandwidth (BW) and during at least a certain time period, e.g., 1 or more symbols, time slots, subframes, frames etc... For example, all signals such as PDSCH , PDCCH, CRS, PSS/SSS etc... in DL may be scaled, i.e. , reduced, by the same amount. The power scaling amount or scaling factor may be pre-defined or autonomously selected based on target quality of signals to be transmitted. In case of UL transmitted signals, the UE or the second radio node 61 1 , 612, 671 , 672, may also be configured by the network node, or the first radio node 61 1 , 640, 650, 671 , with the scaling factor.

As a special case X = 0 dB, i.e., no power scaling. In this case, the transmitting node, such as the second radio node 61 1 , 612, 671 , 672 or, e.g. , the first radio node 61 1 , 671 in some embodiments, may not apply any scaling of power to transmitted signals. This means the transmitting node may transmit at its nominal power or maximum allowed power, e.g. , power class level. For example, pico BS and U E may transmit at their nominal power levels of 24 dBm and 23 dBm, respectively. The scaling factor may be 0 dB in case the frequency of using a better modulation quality than threshold, e.g., the first threshold, is determined to be very low i.e. lower than a second threshold.

Method 2: Unequal power scaling: This method may also be interchangeably called non-linear power scaling. This method may scale the transmit power of at least two sets of radio resources, e.g., RE, RB, PRB, codes etc... of transmitting signals in a cell, such as the first cell 621 , by at least two different scaling factors, with respect to a reference transmit power value. Examples of reference value is the maximum power, pre-defined power level, power level in the previous transmission or maximum power of certain power class of UE or BS. The scaling factor to be applied for a particular set of radio resources may also depend upon the type of radio resource. The scaling may be decrease or reduction in transmit power of radio resources to be used for transmitting the modulated signals. For example, the scaling factors may be x dB for a data channel, e.g., PDSCH, and y dB for control channels, e.g., PDCCH. In another example, the scaling factors may be x dB for physical channels, e.g., PDSCH, PDCCH etc . , and y dB for physical signals, e.g., CRS, PSS, SSS, PRS, DMRS etc... In yet another example, the scaling factors may be x dB for all physical channels, and UE specific physical signals, e.g., PDSCH, PDCCH, DMRS etc., and y dB for common channels and signals, e.g., CRS, PSS, SSS, PRS, PBCH etc... In yet another example, the scaling factors may be x dB for data channels, e.g., PDSCH etc... y dB for control channel, e.g., PDCCH, z dB for common channel, e.g., CRS, PBCH etc... In one example, x > 0 dB, y = z = 0 as a special case; that is, scaling on one type of transmitting signals. This method of scaling may particularly be applied to protect the cell coverage, i.e., by not scaling common signals rather scaling only UE specific signals, e.g., PDSCH, DMRS, PDCCH etc...

According to the foregoing, in some embodiments, the first method scales the transmit power of the one or more radio signals by a same value in all transmitted radio resources, and the second method scales the transmit power of the one or more radio signals belonging to at least a first group of radio resources by a first value, and the transmit power of the one or more radio signals belonging to at least a second group of radio resources by a second value. The first group of radio resources may be wireless device specific signals, e.g., PDSCH, PDCCH, DMRS etc., that is, radio resources not affecting cell coverage, and the second group of radio resources may be cell specific signals, for example, common channels and signals, e.g., CRS, PSS, SSS, PRS, PBCH etc., that is, radio resources that may affect cell coverage, as discussed earlier.

In some embodiments, selecting comprises receiving a selection for the method for scaling the transmit power of the one or more radio signals transmitted by the second radio node 61 1 , 612, 671 , 672 from one of: the second radio node 611 , 612, 671 , 672 or another network node 611 , 612, 640, 650. Further description about this action may be found below under the heading "Selection of power scaling method".

Action 703

The first radio node 61 1 , 640, 650, 671 may send a message to at least one of: the third radio node 61 1 , 612, 671 , 672, a wireless device 671 , 672, the second radio node 61 1 , 612, 671 , 672, and another network node 61 1 , 612, 640, 650. The message comprises an indication of the selected method.

The indication may comprise information related to the selected power scaling method. The information may comprise an identifier of the selected method, e.g. , a predefined identifier, 0 or 1 , associated with the selected method. The information may further contain additional information such as the scaling factor used for scaling different types of signals according to the selected method.

In one example, the information about the method used or expected to be used for scaling the transmit power of DL radio signals is transmitted from a network node, such as the first network node 61 1 , to one or more UEs, such as the first wireless device 671 and the second wireless device 672. In a further example, the information may be sent by the network node to the UE via a Radio Resource Control (RRC) message with a new Information Element, IE, indicating the method and the scaling parameters during the U E, e.g., the first wireless device 671 and the second wireless device 672, setup process. In another example, the information may be sent via a dedicated RRC message.

In another example, the information about the method used or expected to be used for scaling the transmit power of DL radio signals may be transmitted from the network node, such as the first network node 61 1 , to another network node, such as the second network node 612. In one example, the information may be exchanged in X2. In another example, the information may be exchanged using radio interface.

In another example, the information about the method used or expected to be used for scaling the transmit power of UL radio signals is transmitted from the UE, such as the first wireless device 671 , to the network node, e.g. serving network node, such as the first network node 61 1 . The information may also be transmitted by a UE, such as the first wireless device 671 , to another UE, such as the second wireless device 672, if they are both capable of D2D communication. Further description about this action may be found below under the heading

"Signaling information related to the selected power scaling method".

Action 704

The first radio node 611 , 640, 650, 671 may scale the one or more radio signals transmitted by the second radio node 61 1 , 612, 671 , 672, based on the selected method.

The scaling of transmit power may be done in signals transmitted over certain time- frequency resources, e.g., over full or part of BW and in certain time, such as in one or more symbols, time slot, subframe or frame.

In some exemplary embodiments, the scaling may be performed:

• By a BS, e.g., the first network node 161 , itself for scaling its Tx power

• By a UE, e.g., the first wireless device 671 , itself for scaling its Tx power

• By a BS, e.g., the first network node 161 , for scaling Tx power of a UE, e.g., the first wireless device 671

· By a BS, e.g., the first network node 161 , for scaling TX power of another

BS, e.g., the second network node 162,

• By another node, e.g., an RNC such as the controller network node 640, for scaling Tx power of a BS , e.g., the first network node 611.

• By another node, e.g., an RNC such as the controller network node 640, for scaling Tx power of a UE, e.g., the first wireless device 671

• By a UE, e.g., the first wireless device 671 , for scaling Tx power of another UE, e.g., the second wireless device 672

Further description about this action may be found below under the heading "Scaling and transmission of signals based on selected method".

Action 705

In some embodiments wherein the first radio node 611 , 671 is one of a first network node 61 1 and a first wireless device 671 , the first radio node 61 1 , 640, 671 may transmit to the third radio node 611 , 612, 671 , 672 radio signals scaled according to the selected method. Figure 8 illustrates another embodiment that may be performed by the first radio node 611 , 671 , in the embodiments in which the first radio node 61 1 , 671 is a transmitting node, as will be described later.

Embodiments of a method performed by the second radio node 61 1 , 612, 671 , 672 for selecting the method for scaling the transmit power of the one or more radio signals transmitted by the second radio node 61 1 , 612, 671 , 672 to the third radio node 61 1 , 612, 671 , 672, will now be described with reference to the flowchart depicted depicted in

Figure 9. As stated earlier, the second radio node 61 1 uses the modulation scheme.

Also as stated earlier, the second radio node 61 1 , 612, 671 , 672 and the third radio node 611 , 612, 671 , 672 operate in the wireless communications network 600.

Figure 9 depicts a flowchart of the actions that are or may be performed by the first wireless device 671 in embodiments herein. In the Figure, a box with dashed lines indicates that the action is optional.

The method may comprise the following actions, which actions may as well be carried out in another suitable order than that described below. In some embodiments, all the actions may be carried out, whereas in other embodiments only some action/s may be carried out.

The detailed description of some of the following corresponds to the same references provided above, in relation to the actions described for the first radio node 61 1 , 640, 650, 671 , and will thus not be repeated here. For example, in some embodiments, the first radio node 611 , 671 is the same as the second radio node 611 , 671. Action 901

The second radio node 611 , 612, 671 , 672 receives the message described in Action 703 from the first radio node 611 , 640, 650, 671 operating in the wireless communications network 600, wherein the message comprises an indication of the selected method between the first method and the second method for scaling the transmit power of the one or more radio signals, based on information about how often the one or more radio signals modulated using the modulation scheme are used with the transmit modulation quality better than the first threshold, the one or more modulated radio signals being transmitted by the second radio node 61 1 , 612, 671 , 672, and the information being obtained by the first radio node 61 1 , 640, 650, 671 .

Action 902

The second radio node 61 1 , 612, 671 , 672 selects between the first method and the second method for scaling the transmit power of the one or more radio signals, e.g. , transmitted by the second radio node 61 1 , 612, 671 , 672, based on the received message, as described above for action 702.

In some embodiments, the first method scales the transmit power of the one or more radio signals by the same value in all transmitted radio resources, and the second method scales the transmit power of the one or more radio signals belonging to at least a first group of radio resources by the first value, and the transmit power of the one or more radio signals belonging to at least the second group of radio resources by the second value.

Action 903

The second radio node 61 1 , 612, 671 , 672 may scale the one or more radio signals transmitted by the second radio node 61 1 , 612, 671 , 672, based on the selected method, as described above for action 704.

Further description about this action may be found below under the heading "Scaling and transmission of signals based on selected method". The description is similar to that provided in action 704. Action 904

The second radio node 61 1 , 612, 671 , 672 may transmit to the third radio node 61 1 , 612, 671 , 672 radio signals scaled according to the selected method, as described above for action 705. Embodiments of a method performed by the third radio node 61 1 , 612, 671 , 672 for adapting a receiver configuration in the third radio node 61 1 , 612, 671 , 672, will now be described with reference to the flowchart depicted depicted in Figure 10. As stated earlier, the third radio node 611 , 612, 671 , 672 operates in the wireless communications network 600.

Figure 10 depicts a flowchart of the actions that are or may be performed by the third radio node 611 , 612, 671 , 672 in embodiments herein. In the Figure, a box with dashed lines indicates that the action is optional.

The detailed description of some of the following corresponds to the same references provided above, in relation to the actions described for the first radio node 61 1 , 640, 650, 671 , and will thus not be repeated here. For example, in some embodiments, the first radio node 611 , 671 is the same as the second radio node 611 , 671. Action 1001

When the transmit power of the one or more signals being transmitted by the second radio node 611 , 612, 671 , 672 has been scaled as described in actions 704 or 903, the third radio node 61 1 , 612, 671 , 672 receiving the scaled one or more signals, may need to adapt its receiver to the transmission power of scaled one or more signals to optimize reception for the changed transmission power, and for example, avoid

interference. The scaling of the transmit power of the one or more signals transmitted by the second radio node 611 , 612, 671 , 672 may result in lower SINR or SNR, e.g., SINR of -4 dB, experienced at the third radio node 61 1 , 612, 671 , 672. By adapting the receiver, the third radio node 61 1 , 612, 671 , 672 may enable reception of signals even at lower SINR level.

In order to find out if the transmission power of the one or more signals has been scaled, in this action, the third radio node 611 , 612, 671 , 672 receives the message described in Action 703 from the first radio node 611 , 640, 650, 671 operating in the wireless communications network 600, wherein the message comprises the indication of the selected method between the first method and the second method for scaling the transmit power of the one or more radio signals transmitted by the second radio node 61 1 , 612, 671 , 672 operating in the wireless communications network 600, the second radio node 61 1 using the modulation scheme, the selected method having been selected based on the information about how often the one or more radio signals modulated using the modulation scheme are used with the transmit modulation quality better than the first threshold, the one or more modulated radio signals being transmitted by the second radio node 61 1 , 612, 671 , 672, and the information being obtained by the first radio node 61 1 , 640, 650, 671.

In some embodiments, the message further comprises an amount of power scaling used by the first radio node 611 , 640, 650, 671 , as described above in relation to Action 702.

Action 1002

Once the third radio node 611 , 612, 671 , 672 has found out whether the transmit power of the one or more radio signals has been scaled, to optimize reception of the one or more radio signals, in this action, the third radio node 611 , 612, 671 , 672 adapts the receiver configuration in the third radio node 611 , 612, 671 , 672, based on the received message. A receiver may be understood here as a processor configured to receive signals in the presence of noise and interference, provided the received SINR is above a threshold, e.g. -5 dB. Examples of such receivers are Minimum Mean Square Error Maximum Ratio Combining (MMSE-MRC), MMSE Interference Rejection and Combining (MMSE-IRC), etc...

The adaptation of receiver configuration or one or more parameters may comprise adapting one or more of the following procedures:

Changing a duration over which the channel estimation is valid, e.g., longer duration if method 2 is used, since power scaling may vary faster.

· Selection of type of reference signals to be used for channel estimation, e.g., signals which are scaled least.

Selection between type of receiver types in the UE, e.g., 1) use receiver that may mitigate interference within the cell due to leakage of power across radio resources when method 2 is used, 2) use more robust receiver which may more effectively reduce interference in case scaling factor is above a threshold, e.g., 3 dB or more.

Duration over which measurement is done, e.g., longer duration if method 1 is used, to have better averaging. Hence, in some embodiments, the adapting comprises at least one of: changing a duration over which a channel estimation is valid, selecting a type of reference signals to be used for channel estimation, selecting a type of receiver types in the third radio node 611 , 612, 671 , 672, and selecting a duration over which a signal measurement is performed .

As stated earlier, in some embodiments, the first method scales the transmit power of the one or more radio signals by the same value in all transmitted radio resources, and the second method scales the transmit power of the one or more radio signals belonging to at least the first group of radio resources by the first value, and the transmit power of the one or more radio signals belonging to at least the second group of radio resources by the second value.

Action 1003

Once the third radio node 61 1 , 612, 671 , 672 has optimized reception, in this action, the third radio node 611 , 612, 671 , 672 may receive through the adapted receiver, radio signals from the second radio node 611 , 612, 671 , 672, the radio signals being scaled according to the selected method.

Figure 11 illustrates another embodiment that may be performed by the third radio node 61 1 , 612, 671 , 672, which is a receiving node, as will be described later.

Embodiments described herein may have the advantage of facilitating the usage of the better modulation quality, e.g., higher order modulation, while maintaining the system performance, e.g., the performance of the wireless communications network 600, through appropriate power scaling at the base station, e.g., at the first radio node 611 , or at the second radio node 611 , 612. It may also have the advantage of avoiding fluctuation in cell coverage, e.g., CRS, PSS/SSS, PBCH etc . , as well as ensuring better cell coverage and allowing more power for data.

Embodiments described herein may have the advantage of also preventing unnecessary increase in cell load in a macro cell such as the first cell 621 served by a HPN, such as the first network node 611. This may enhance the ability of the macro cell, such as the first cell 621 , to serve users which cannot be offloaded to small cells e.g. pico or micro cells.

To perform the method actions described above in relation to Figures 7-8, the first radio node 61 1 , 640, 650, 671 is configured to select the method for scaling the transmit power of one or more radio signals configured to be transmitted by the second radio node 611 , 612, 671 , 672 to the third radio node 61 1 , 612, 671 , 672. The first radio node 61 1 , 640, 650, 671 comprises the following arrangement depicted in Figure 12. As stated earlier, the second radio node is configured to use the modulation scheme. Also as stated earlier, the first radio node 611 , 640, 650, 671 , the second radio node 611 , 612, 671 , 672, and the third radio node 611 , 612, 671 , 672 are configured to operate in the wireless communications network 600. The detailed description of some of the following corresponds to the same references provided above, in relation to the actions described for the first radio node 611 , 640, 650, 671 , and will thus not be repeated here.

In some embodiments, the first radio node 611 , 640, 650, 671 is the first radio network node 61 1.

In some embodiments, the first radio node 671 is the first wireless device 671 and the third radio node 61 1 , 672 is the radio network node 61 1 or the second wireless device 672.

In some embodiments, the first radio node 611 , 671 is the second radio node 61 1 ,

671.

The first radio node 611 , 640, 650, 671 is configured to obtain the information about how often the one or more radio signals, modulated using the modulation scheme, are used with a transmit modulation quality better than the first threshold, the one or more modulated radio signals being configured to be transmitted by the second radio node 61 1 , 612, 671 , 672.

In some embodiments, this may be implemented by an obtaining module 1201 comprised in the first radio node 611 , 640, 650, 671.

In some embodiments, the one or more modulated radio signals are configured to be modulated using the number of modulated symbols. In some embodiments, the one or more modulated radio signals are configured to be modulated using HOM, which satisfies the condition that the number of modulated symbols is above the second threshold.

In some embodiments, the HOM is 256 QAM, the number of modulated symbols is 256 and the second threshold is 128 symbols.

In some embodiments, the transmit modulation quality of the one or more modulated radio signals is at least one of: the Error Vector Magnitude, the frequency error and the time alignment between signals from any two pair of transmit antennas.

In some embodiments, the first threshold is determined by the first radio node 61 1 , 640, 650, 671 autonomously, or based on input received from another network node 612, 640, 650.

In some embodiments, the information is based on at least one of: the statistics of usage by the first radio node 611 , 640, 650, 671 of a better modulation quality, the amount of data in a buffer for transmission of the first radio node 611 , 640, 671 , the operation of a cell on/off scheme in neighboring cells to the first radio node 61 1 , 640, 671 , the cell deployment of the first radio node 61 1 , 640, 671 , and the category or capability of a receiving wireless device 671 , 672.

In some embodiments, to obtain comprises one of: to determine the information and to receive the information.

The first radio node 611 , 640, 650, 671 is configured to select between the first method and the second method for scaling the transmit power of the one or more radio signals, e.g., configured to be transmitted by the second radio node 61 1 , 612, 671 , 672, based on the obtained information.

This may be implemented by a selecting module 1202 comprised in the first radio node 61 1 , 640, 650, 671.

In some embodiments, the first method is configured to scale the transmit power of the one or more radio signals by the same value in all radio resources configured to be transmitted, and the second method is configured to scale the transmit power of the one or more radio signals belonging to at least the first group of radio resources by the first value, and the transmit power of the one or more radio signals belonging to at least the second group of radio resources by the second value. This may also be implemented by the selecting module 1202.

In some embodiments, to select comprises to receive a selection for the method for scaling the transmit power of the one or more radio signals configured to be transmitted by the second radio node 61 1 , 612, 671 , 672 from one of: the second radio node 61 1 , 612, 671 , 672 or another network node 611 , 612, 640, 650. This may also be

implemented by the selecting module 1202.

In some embodiments, the first radio node 611 , 640, 650, 671 may be further configured to send the message to at least one of: the third radio node 61 1 , 612, 671 , 672, the wireless device 671 , 672, the second radio node 611 , 612, 671 , 672, and the another network node 61 1 , 612, 640, 650, the message comprising an indication of the selected method.

This may be implemented by a sending module 1203 comprised in the first radio node 61 1 , 640, 650, 671.

In some embodiments, the first radio node 611 , 640, 650, 671 may be further configured to scale the one or more radio signals configured to be transmitted by the second radio node 611 , 612, 671 , 672, based on the selected method.

This may be implemented by a scaling module 1204 comprised in the first radio node 61 1 , 640, 650, 671.

In some embodiments wherein the first radio node 61 1 , 671 is one of the first network node 611 and the first wireless device 671 , the first radio node 61 1 , 640, 671 may be further configured to transmit to the third radio node 611 , 612, 671 , 672 the radio signals scaled according to the selected method.

This may be implemented by a transmitting module 505 comprised in the first radio node 61 1 , 671. These embodiments are represented in Figure 12 with a dashed line.

The embodiments herein for selecting a method for scaling a transmit power of one or more radio signals configured to be transmitted by a second radio node 61 1 , 612, 671 , 672 to a third radio node 611 , 612, 671 , 672 may be implemented through one or more processors, such as the processing module 1206 in the first radio node 611 , 640, 650, 671 depicted in Figure 12, together with computer program code for performing the functions and actions of the embodiments herein. The program code mentioned above may also be provided as a computer program product, for instance in the form of a data carrier carrying computer program code for performing the embodiments herein when being loaded into the in the first radio node 61 1 , 640, 650, 671. One such carrier may be in the form of a CD ROM disc. It may be however feasible with other data carriers such as a memory stick. The computer program code may furthermore be provided as pure program code on a server and downloaded to the first radio node 61 1 , 640, 650, 671.

The first radio node 611 , 640, 650, 671 may further comprise a memory module

1207 comprising one or more memory units. The memory module 1207 may be arranged to be used to store data in relation to applications to perform the methods herein when being executed in the first radio node 611 , 640, 650, 671. Memory module 1207 may be in communication with the processing module 1206. Any of the other information processed by the processing module 1206 may also be stored in the memory module 507.

In some embodiments, information may be received from, e.g., the third radio node 611 , 612, 671 , 672, or another network node 612, 640, 650, through a receiving port

1208. In some embodiments, the receiving port 1208 may be, for example, connected to one or more antennas in the first radio node 611 , 671. In other embodiments, the first network node 61 1 may receive information from another structure in the wireless communications network 600 through the receiving port 1208. Since the receiving port 1208 may be in communication with the processing module 506, the receiving port 1208 may then send the received information to the processing module 506. The receiving port

1208 may also be configured to receive other information.

The information processed by the processing module 1206 in relation to the embodiments of the method herein may be stored in the memory module 1207 which, may be in communication with the processing module 1206, as stated earlier, and with the receiving port 1208. The processing module 1206 may be further configured to transmit or send information to e.g., the second radio node 61 1 , 612, 671 , 672, through a sending port 1209, which may be in communication with the processing module 1206, and the memory module 1207.

Those skilled in the art will also appreciate that the different modules 1201-1205 described above may refer to a combination of analog and digital modules, and/or one or more processors configured with software and/or firmware, e.g., stored in memory, that, when executed by the one or more processors such as the processing module 1206, perform as described above. One or more of these processors, as well as the other digital hardware, may be included in a single Application-Specific Integrated Circuit (ASIC), or several processors and various digital hardware may be distributed among several separate components, whether individually packaged or assembled into a System-on-a- Chip (SoC).

Also, in some embodiments, the different modules 1201-1205 described above may be implemented as one or more applications running on one or more processors such as the processing module 1206.

Thus, the methods according to the embodiments described herein for the first radio node 61 1 , 640, 650, 671 are respectively implemented by means of a computer program product, comprising instructions, i.e., software code portions, which, when executed on at least one processor, cause the at least one processor to carry out the actions described herein, as performed by the first radio node 61 1 , 640, 650, 671. The computer program product may be stored on a computer-readable storage medium. The computer-readable storage medium, having stored thereon the computer program, comprises instructions which, when executed on at least one processor, cause the at least one processor to carry out the actions described herein, as performed by the first radio node 61 1 , 640, 650, 671. In some embodiments, the computer-readable storage medium may be a non-transitory computer-readable storage medium, such as a CD ROM disc, or a memory stick. To perform the method actions described above in relation to Figure 9, the second radio node 61 1 , 612, 671 , 672 is configured to select the method for scaling the transmit power of the one or more radio signals configured to be transmitted by the second radio node 61 1 , 612, 671 , 672 to the third radio node 61 1 , 612, 671 , 672. The second radio node 61 1 , 612, 671 , 672 comprises the following arrangement depicted in Figure 13. The second radio node 611 is configured to use the modulation scheme. The second radio node 61 1 , 612, 671 , 672 and the third radio node 61 1 , 612, 671 , 672 are configured to operate in the wireless communications network 600. The detailed description of some of the following corresponds to the same references provided above, in relation to the actions described for the second radio node 611 , 612, 671 , 672, and will thus not be repeated here.

In some embodiments, the first radio node 61 1 , 671 is the second radio node 61 1 ,

671.

The second radio node 611 , 612, 671 , 672 is configured to receive the message from the first radio node 611 , 640, 650, 671 configured to operate in the wireless communications network 600, wherein the message comprises the indication of the selected method between a first method and a second method for scaling the transmit power of the one or more radio signals modulated using the modulation scheme, based on the information about how often the one or more modulated radio signals are used with a transmit modulation quality better than the first threshold, the one or more modulated radio signals being configured to be transmitted by the second radio node 61 1 , 612, 671 , 672, and the information being configured to be obtained by the first radio node 61 1 , 640, 650, 671.

In some embodiments, this may be implemented by a receiving module 1301 comprised in the second radio node 611 , 612, 671 , 672.

In some embodiments, the second radio node 611 , 612, 671 , 672 may be further configured to select between the first method and the second method for scaling the transmit power of the one or more radio signals, based on the received message. This may be implemented by a selecting module 1302 comprised in the second radio node 61 1 , 612, 671 , 672.

In some embodiments, the first method is configured to scale the transmit power of the one or more radio signals by the same value in all radio resources configured to be transmitted, and the second method is configured to scale the transmit power of the one or more radio signals belonging to at least the first group of radio resources by the first value, and the transmit power of the one or more radio signals belonging to at least the second group of radio resource by the second value. This may also be implemented by the selecting module 1302.

In some embodiments, the second radio node 611 , 612, 671 , 672 may be further configured to scale the one or more radio signals configured to be transmitted by the second radio node 611 , 612, 671 , 672, based on the selected method.

This may be implemented by a scaling module 1303 comprised in the second radio node 61 1 , 612, 671 , 672.

In some embodiments, the second radio node 611 , 612, 671 , 672 may be further configured to transmit to the third radio node 61 1 , 612, 671 , 672 radio signals scaled according to the selected method.

This may be implemented by a transmitting module 1304 comprised in the second radio node 61 1 , 612, 671 , 672.

The embodiments herein for selecting a method for scaling a transmit power of one or more radio signals configured to be transmitted by the second radio node 61 1 , 612, 671 , 672 to a third radio node 611 , 612, 671 , 672 may be implemented through one or more processors, such as the processing module 1305 in the second radio node 61 1 , 612, 671 , 672 depicted in Figure 13, together with computer program code for performing the functions and actions of the embodiments herein. The program code mentioned above may also be provided as a computer program product, for instance in the form of a data carrier carrying computer program code for performing the embodiments herein when being loaded into the in the second radio node 611 , 612, 671 , 672. One such carrier may be in the form of a CD ROM disc. It may be however feasible with other data carriers such as a memory stick. The computer program code may furthermore be provided as pure program code on a server and downloaded to the second radio node 611 , 612, 671 , 672.

The second radio node 611 , 612, 671 , 672 may further comprise a memory module 1306 comprising one or more memory units. The memory module 1306 may be arranged to be used to store data in relation to applications to perform the methods herein when being executed in the second radio node 611 , 612, 671 , 672. Memory module 1306 may be in communication with the processing module 1305. Any of the other information processed by the processing module 1305 may also be stored in the memory module 1306.

In some embodiments, information may be received from, e.g., first radio node 61 1 , 640, 650, 671 , through a receiving port 1307. In some embodiments, the receiving port 1307 may be, for example, connected to the one or more antennas in the second radio node 61 1 , 612, 671 , 672. In other embodiments, the second radio node 611 , 612, 671 , 672 may receive information from another structure in the wireless communications network 600 through the receiving port 1307. Since the receiving port 1307 may be in communication with the processing module 1305, the receiving port 1307 may then send the received information to the processing module 1305. The receiving port 1307 may also be configured to receive other information.

The information processed by the processing module 1305 in relation to the embodiments of method herein may be stored in the memory module 1306 which, as stated earlier, may be in communication with the processing module 1305 and the receiving port 1307.

The processing module 1305 may be further configured to transmit or send information to e.g., the third radio node 611 , 612, 671 , 672, through a sending port 1308, which may be in communication with the processing module 1305, and the memory module 1306.

Those skilled in the art will also appreciate that the different modules 1301-1304 described above may refer to a combination of analog and digital modules, and/or one or more processors configured with software and/or firmware, e.g., stored in memory, that, when executed by the one or more processors such as the processing module 1305, perform as described above. One or more of these processors, as well as the other digital hardware, may be included in a single Application-Specific Integrated Circuit (ASIC), or several processors and various digital hardware may be distributed among several separate components, whether individually packaged or assembled into a System-on-a- Chip (SoC).

Also, in some embodiments, the different modules 1301-1304 described above may be implemented as one or more applications running on one or more processors such as the processing module 1305.

Thus, the methods according to the embodiments described herein for the second radio node 61 1 , 612, 671 , 672 are respectively implemented by means of a computer program product, comprising instructions, i.e., software code portions, which, when executed on at least one processor, cause the at least one processor to carry out the actions described herein, as performed by the second radio node 611 , 612, 671 , 672. The computer program product may be stored on a computer-readable storage medium. The computer-readable storage medium, having stored thereon the computer program, comprises instructions which, when executed on at least one processor, cause the at least one processor to carry out the actions described herein, as performed by the second radio node 61 1 , 612, 671 , 672. In some embodiments, the computer-readable storage medium may be a non-transitory computer-readable storage medium, such as a CD ROM disc, or a memory stick. To perform the method actions described above in relation to Figures 10 and 1 1 , the third radio node 611 , 612, 671 , 672 is configured to adapt the receiver configuration in the third radio node 611 , 612, 671 , 672. The third radio node 611 , 612, 671 , 672 comprises the following arrangement depicted in Figure 14. The third radio node 611 , 612, 671 , 672 is configured to operate in the wireless communications network 600. The detailed description of some of the following corresponds to the same references provided above, in relation to the actions described for the third radio node 61 1 , 612, 671 , 672, and will thus not be repeated here. In some embodiments, the first radio node 61 1 , 671 is the second radio node 61 1 ,

The third radio node 611 , 612, 671 , 672 is configured to receive the message from the first radio node 61 1 , 640, 650, 671 configured to operate in the wireless

communications network 600, wherein the message comprises the indication of the selected method between the first method and the second method for scaling the transmit power of the one or more radio signals configured to be transmitted by the second radio node 611 , 612, 671 , 672 configured to operate in the wireless communications network 600. The second radio node 61 1 is configured to use the modulation scheme, the selected method having been selected based on the information about how often the one or more modulated using the modulation scheme radio signals are used with a transmit modulation quality better than the first threshold, the one or more modulated radio signals being configured to be transmitted by the second radio node 611 , 612, 671 , 672, and the information is configured to be obtained by the first radio node 611 , 640, 650, 671.

In some embodiments, this may be implemented by a receiving module 1401 comprised in the third radio node 61 1 , 612, 671 , 672.

In some embodiments, the first method is configured to scale the transmit power of the one or more radio signals by the same value in all radio resources configured to be transmitted, and the second method is configured to scale the transmit power of the one or more radio signals belonging to at least the first group of radio resources by the first value, and the transmit power of the one or more radio signals belonging to at least the second group of radio resources by the second value.

In some embodiments, the message further comprises the amount of power scaling configured to be used by the first radio node 611 , 640, 650, 671.

The third radio node 611 , 612, 671 , 672 is configured to adapt the receiver configuration in the third radio node 61 1 , 612, 671 , 672, based on the received message.

This may be implemented by an adapting module 1402 comprised in the third radio node 61 1 , 612, 671 , 672. In some embodiments, to adapt comprises at least one of: to change the duration over which the channel estimation is valid, to select the type of reference signals to be used for channel estimation, to select the type of receiver types in the third radio node 611 , 612, 671 , 672, and to select the duration over which a signal measurement is performed. This may also be implemented by the adapting module 1402.

In some embodiments, the third radio node 611 , 612, 671 , 672 may be further configured to receive through the adapted receiver, radio signals from the second radio node 61 1 , 612, 671 , 672, the radio signals being configured to be scaled according to the selected method.

This may also be implemented by the receiving module 1401.

The embodiments herein for adapting a receiver configuration in the third radio node 611 , 612, 671 , 672 may be implemented through one or more processors, such as the processing module 1403 in the third radio node 611 , 612, 671 , 672 depicted in Figure 14, together with computer program code for performing the functions and actions of the embodiments herein. The program code mentioned above may also be provided as a computer program product, for instance in the form of a data carrier carrying computer program code for performing the embodiments herein when being loaded into the in the third radio node 611 , 612, 671 , 672. One such carrier may be in the form of a CD ROM disc. It may be however feasible with other data carriers such as a memory stick. The computer program code may furthermore be provided as pure program code on a server and downloaded to the third radio node 611 , 612, 671 , 672. The third radio node 611 , 612, 671 , 672 may further comprise a memory module

1404 comprising one or more memory units. The memory module 1404 may be arranged to be used to store data in relation to applications to perform the methods herein when being executed in the third radio node 611 , 612, 671 , 672. Memory module 1404 may be in communication with the processing module 1403. Any of the other information processed by the processing module 1403 may also be stored in the memory module

1404. In some embodiments, information may be received from, e.g., first radio node 61 1 , 640, 650, 671 , through a receiving port 1405. In some embodiments, the receiving port 1405 may be, for example, connected to the one or more antennas in the third radio node 611 , 612, 671 , 672. In other embodiments, the third radio node 611 , 612, 671 , 672 may receive information from another structure in the wireless communications network 600 through the receiving port 1405. Since the receiving port 1405 may be in communication with the processing module 1403, the receiving port 1405 may then send the received information to the processing module 1403. The receiving port 1405 may also be configured to receive other information.

The information processed by the processing module 1403 in relation to the embodiments of the method herein may be stored in the memory module 1404 which, as stated earlier, may be in communication with the processing module 1403 and the receiving port 1405. The processing module 1403 may be further configured to transmit or send information to e.g., the third radio node 611 , 612, 671 , 672, through a sending port 1406, which may be in communication with the processing module 1403, and the memory module 1404. Those skilled in the art will also appreciate that the different modules 1401-1402 described above may refer to a combination of analog and digital modules, and/or one or more processors configured with software and/or firmware, e.g., stored in memory, that, when executed by the one or more processors such as the processing module 1403, perform as described above. One or more of these processors, as well as the other digital hardware, may be included in a single Application-Specific Integrated Circuit (ASIC), or several processors and various digital hardware may be distributed among several separate components, whether individually packaged or assembled into a System-on-a- Chip (SoC).

Also, in some embodiments, the different modules 1401-1402 described above may be implemented as one or more applications running on one or more processors such as the processing module 1403. Thus, the methods according to the embodiments described herein for the third radio node 61 1 , 612, 671 , 672 are respectively implemented by means of a computer program product, comprising instructions, i.e., software code portions, which, when executed on at least one processor, cause the at least one processor to carry out the actions described herein, as performed by the third radio node 611 , 612, 671 , 672. The computer program product may be stored on a computer-readable storage medium. The computer-readable storage medium, having stored thereon the computer program, comprises instructions which, when executed on at least one processor, cause the at least one processor to carry out the actions described herein, as performed by the third radio node 61 1 , 612, 671 , 672. In some embodiments, the computer-readable storage medium may be a non-transitory computer-readable storage medium, such as a CD ROM disc, or a memory stick.

The modules described may be for performing any of the pertinent embodiments described.

When using the word "comprise" or "comprising" it shall be interpreted as non- limiting, i.e. meaning "consist at least of". The embodiments herein are not limited to the above described preferred

embodiments. Various alternatives, modifications and equivalents may be used.

Therefore, the above embodiments should not be taken as limiting the scope of the invention. Further description of embodiments herein, which may be combined in whole or in part with the description just provided:

The following provides a description in other words, and/or further description, of the actions described above.

Embodiments herein may comprise methods in a transmitting radio node, such as the first radio node 611 , 671 , in some embodiments, and the second radio node 61 1 , 612, 671 , 672, and a receiving radio node, such as the third radio node 61 1 , 612, 671 , 672. The transmitting node, e.g. a network node such as the first network node 61 1 , may determine a frequency of using radio signals such as the one or more modulated radio signals, e.g., DL signals, with a modulation quality better than a threshold, e.g., the first threshold. Then, it may select one of the power scaling methods for transmission of the radio signals. The receiving node, such as the third radio node 611 , 612, 671 , 672, e.g. a UE such as the first wireless device 671 , may also be informed about the power scaling method used by the transmitting node. The receiving node may adapt its receiver configuration accordingly and may use it for receiving signals, such as the scaled radio signals, from the transmitting node.

The actions that may be performed in a transmitting node, such as the first radio node 61 1 , 671 , in some embodiments, and the second radio node 611 , 612, 671 , 672 in some embodiments, e.g. a base station such as the first network node 611 , a UE such as the first wireless device 671 , may comprise:

· Determining a frequency of using one or more radio signals with a transmit modulation quality better than a threshold, e.g., the first threshold;

Selecting one of a method 1 , such as the first method, and a method 2, such as the second method, for scaling a transmit power of a radio signal, such as one radio signal transmitted by the second radio node 611 , 612, 671 , 672, based on the determined frequency in the previous action, wherein the method 1 may scale the transmit power of radio signals by the same value or scaling factor in all transmitted radio resources, and the method 2 may scale the transmit power of radio signals belonging to at least a first group of radio resources and a second group of radio resources, by a first scaling factor and second scaling factor, respectively.

· Transmitting the scaled radio signals for use by a receiving node, such as the third radio node 611 , 612, 671 , 672.

The actions that may be performed in a receiving node, such as the third radio node 611 , 612, 671 , 672, e.g. a base station such as the first network node 61 1 , or a UE such as the first wireless device 671 , may comprise:

Receiving from a transmitting node, such as the first radio node 611 , 671 , in some embodiments, and the second radio node 61 1 , 612, 671 , 672, information related to one of the two transmit power scaling methods used for scaling transmit power of a radio signal transmitted by the transmitting node, wherein the method 1 may scale the transmit power of radio signals by the same value or scaling factor in all transmitted radio resources, and the method 1 may scale the transmit power of radio signals belonging to at least a first group of radio resources and a second group of radio resources by a first scaling factor and second scaling factor, respectively.

Adapting a receiver configuration of the receiving node based on the received information;

Receiving the radio signals using the receiver with the adapted configuration.

The actions performed in a transmitting node as described herein, may comprise:

Determining the frequency of using transmit signals of better modulation quality.

· Selecting, based on the determination, between the method 1 , e.g., the first method, or the method 2, e.g., the second method, for scaling transmit power of radio signal to be transmitted.

Scaling the transmit power of radio signals and transmitting the radio signals with scaled transmit power.

The additional or optional steps performed in a transmitting node as described herein may comprise:

Transmitting information related to selected power scaling method to other nodes.

An embodiment of the actions that may be performed in a transmitting node, e.g. a network node, such as the first network node 61 1 , is depicted in Figure 8, and each action is explained above with more details. The same scheme is applicable to a UE, such as the first wireless device 671 , transmitting a radio signal. The node, e.g., first radio node 611 , 640, 650, 671 , may determine the frequency of using certain type of signals, e.g., one or more modulated radio signals, with a modulation quality better than a threshold, e.g., the first threshold. For example, the node, e.g., the first radio node 611 , 640, 650, 671 , in this action may determine, based on one or more criteria, whether certain type of signals with a modulation quality better than a threshold, e.g., the first threshold, is used more frequently or not. Typically, the node transmitting the signals, i.e., the transmitting node such as the first radio node 61 1 , 671 in some embodiments, may determine this frequency of usage.

This may be performed as described above for action 701.

Selection of power scaling method

In this action, the node, e.g., the first radio node 611 , 640, 650, 671 , may select the transmit power scaling method, such as the method for scaling the transmit power of the one or more radio signals transmitted by the second radio node 61 1 , 612, 671 , 672, based on the determined frequency of usage of signals with better modulation quality.

The selection may be typically done by the node that determines the frequency of using a better modulation quality or the node that has the information the frequency of using a better modulation quality, such as the first radio node 611 , 640, 650, 671. In case the selection of power scaling method for UL signals transmitted by the UE, e.g., the second radio node 611 , 612, 671 , 672, is done by the network node e.g., the first network node 61 1 , the controller network node 640, or the one or more central network nodes 650, then the network node e.g., the first network node 61 1 , the controller network node 640, or the one or more central network nodes 650, may indicate the UE about the selected method. The UE may then apply the selected method for scaling the power, as described later.

This may be performed as described above for action 702. Scaling and transmission of signals based on selected method

At the third action, the transmitting node, such as the second radio node 611 , 612, 671 , 672, may scale the transmit power of radio signals to be transmitted according to the selected method in step 2, and then may transmit the radio signals with scaled transmit power. The transmitted signals may be received by the receiving node, i.e., the third radio node 61 1 , 612, 671 , 672.

The transmitting node may also store the information related to the applied power scaling method and the signals on which it has applied the scaling. This may be performed as described above for actions 704 and 903.

Signaling information related to the selected power scaling method

Optionally, the information about the method used or expected to be used for scaling the transmit power of DL radio signals may be sent to the other network nodes, e.g., the third radio node 611 , 612, 671 , 672, a wireless device 671 , 672, the second radio node 61 1 , 612, 671 , 672, and another network node 611 , 612, 640, 650. Typically, the transmitting node, such as the first radio node 611 , 671 in some embodiments and the second radio node 611 , 612, 671 , 672, may send this information to another node, which may be network node e.g., the first network node 611 , the controller network node 640, or the one or more central network nodes 650, or a UE, i.e., a wireless device.

This may be performed as described above for action 703.

Methods in a receiving radio node, such as the third radio node 611, 612, 671, 672.

This embodiment may be applicable to any node or radio node, such as the third radio node 61 1 , 612, 671 , 672, receiving a signal, or more specifically, modulated signal, from the transmitting node, such as the first radio node 611 , 671 in some embodiments and the second radio node 611 , 612, 671 , 672. The radio node herein is interchangeably called as receiving node, radio receiver or receiving radio node. The receiving radio node or simply node may be be a radio network node, e.g. a base station such as the first network node 611 , receiving signals from a UE, such as the first wireless device 671 , or a UE, such as the first wireless device 671 , receiving signals from a radio network node, such as the first network node 61 1.

The actions performed in a receiving node may comprise:

Receiving information about the selected power scaling method. This corresponds to Action 1001.

Adapting a receiver configuration based on the received information. This corresponds to Action 1002.

Receiving radio signals sent by the transmitting node, such as the first radio node 611 , 671 in some embodiments and the second radio node 61 1 , 612, 671 , 672, using the adapted receiver. This corresponds to action 1003. Exemplary methods implemented in a receiving node, e.g., a UE, such as the first wireless device 671 , are depicted in Figure 11.

In one example, in the first action, the receiving node, e.g., UE, may receive the information about the method used or expected to be used for scaling the transmit power of radio signals from the transmitting node, e.g., network node, wherein the method is any of the aforementioned power scaling method 1 , such as the first method, or method 2, such as the second method. The receiving node may then store the received information related to one or more of the expected signals to be received at the receiver of the receiving node from the transmitting node. The received information may also comprise the amount of power scaling applied to different signals, types of signals whose power has been scaled according to the selected scaling factor etc...

In the second action, the receiving node, e.g., UE, may adapt its receiver configuration or associated parameter/s of a receiver for receiving signals, which are scaled at the transmitting node, such as the first radio node 61 1 , 671 in some

embodiments and the second radio node 611 , 612, 671 , 672, according to the indicated method in action 1.

The receiving node, such as the third radio node 611 , 612, 671 , 672, may also store the adapted receiver configuration and use it for receiving the signals at the next time instant and/or at a future time.

In the third action, the receiving node, e.g., UE, may use the adapted receiver configuration of its radio receiver for receiving the radio signals transmitted by the transmitting node, such as the first radio node 61 1 , 671 in some embodiments and the second radio node 611 , 612, 671 , 672, wherein the transmit power of at least one radio signal has been scaled according to one of the power scaling method.

Claims

CLAIMS:

A method performed by a first radio node (640) for selecting a method for scaling a transmit power of one or more radio signals transmitted by a second radio node (611) to a third radio node (671), the second radio node (61 1) using a modulation scheme, the method comprising:

obtaining (701) information about how often one or more radio signals, modulated using the modulation scheme, are used with a transmit modulation quality better than a first threshold, the one or more modulated radio signals being transmitted by the second radio node (61 1), and

selecting (702) between a first method and a second method for scaling the transmit power of the one or more radio signals, based on the obtained information.

2. The method for selecting of claim 1 , wherein the first method scales the transmit power of the one or more radio signals by a same value in all transmitted radio resources, and the second method scales the transmit power of the one or more radio signals belonging to at least a first group of radio resources by a first value, and the transmit power of the one or more radio signals belonging to at least a second group of radio resources by a second value.

3. The method for selecting of claim 2, wherein the one or more modulated radio signals are modulated using Higher Order Modulation, HOM, which satisfies a condition that the number of modulated symbols is above a second threshold.

4. The method for selecting of claim 3, wherein the HOM is 256 Quadrature Amplitude Modulation, QAM, and the number of modulated symbols is 256 and the second threshold is 128 symbols.

5. The method for selecting of any of claims 1-4, wherein the transmit modulation quality of the one or more modulated radio signals is at least one of: an Error Vector Magnitude, a frequency error and a time alignment between signals from any two pair of transmit antennas.

6. The method for selecting of any of claims 1-5, wherein the first threshold is

determined by the first radio node (640) autonomously or based on input received from another network node (612, 650).

7. The method for selecting of any of claims 1-6, wherein the information is based on at least one of: statistics of usage by the first radio node (640) of a better modulation quality, an amount of data in a buffer for transmission of the first radio node (640), an operation of a cell on/off scheme in neighboring cells to the first radio node (640), a cell deployment of the first radio node (640), and a category or capability of a receiving wireless device (671 , 672).

8. The method for selecting of any of claims 1-7, further comprising sending (703) a message to at least one of: the third radio node (671), a wireless device (671 , 672), the second radio node (61 1), and another network node (611 , 612, 650), the message comprising an indication of the selected method.

9. The method for selecting of any of claims 1-8, further comprising scaling (704) the one or more radio signals transmitted by the second radio node (61 1), based on the selected method.

10. Computer program, comprising instructions which, when executed on at least one processor, cause the at least one processor to carry out the method according to any one of claims 1 to 9.

1 1. A computer-readable storage medium, having stored thereon a computer program, comprising instructions which, when executed on at least one processor, cause the at least one processor to carry out the method according to any one of claims 1 to

12. A method performed by a third radio node (671) for adapting a receiver

configuration in the third radio node (671), the method for adapting comprising: receiving (1001) a message from a first radio node (640), wherein the message comprises an indication of a selected method between a first method and a second method for scaling a transmit power of one or more radio signals transmitted by a second radio node (611), the second radio node (61 1) using a modulation scheme, the selected method having been selected based on information about how often one or more radio signals, modulated using the modulation scheme, are used with a transmit modulation quality better than a first threshold, the one or more modulated radio signals being transmitted by the second radio node (611), and the information being obtained by the first radio node (640); and

adapting (1002) the receiver configuration in the third radio node (671), based on the received message.

13. The method for adapting of claim 12, wherein the first method scales the transmit power of the one or more radio signals by a same value in all transmitted radio resources, and the second method scales the transmit power of the one or more radio signals belonging to at least a first group of radio resources by a first value, and the transmit power of the one or more radio signals belonging to at least a second group of radio resources by a second value.

14. The method for adapting of any of claims 12-13, further comprising receiving (1003) through the adapted receiver, radio signals from the second radio node (61 1), the radio signals being scaled according to the selected method.

15. The method for adapting of any of claims 12-14, wherein the message further

comprises an amount of power scaling used by the first radio node (640).

16. The method for adapting of any of claims 12-15, wherein the adapting (1002)

comprises at least one of: changing a duration over which a channel estimation is valid, selecting a type of reference signals to be used for channel estimation, selecting a type of receiver types in the third radio node (671), and selecting a duration over which a signal measurement is performed.

17. Computer program, comprising instructions which, when executed on at least one processor, cause the at least one processor to carry out the method according to any one of claims 12 to 16.

18. A computer-readable storage medium, having stored thereon a computer program, comprising instructions which, when executed on at least one processor, cause the at least one processor to carry out the method according to any one of claims 12 to 16.

19. A method performed by a second radio node (611) for selecting a method for

scaling a transmit power of one or more radio signals transmitted by the second radio node (61 1) to a third radio node (671), the second radio node (611) using a modulation scheme, the method for selecting comprising:

receiving (901) a message from a first radio node (640), wherein the message comprises an indication of a selected method between a first method and a second method for scaling the transmit power of the one or more radio signals, based on information about how often one or more radio signals, modulated using the modulation scheme, are used with a transmit modulation quality better than a first threshold, the one or more modulated radio signals being transmitted by the second radio node (611), and the information being obtained by the first radio node (640), and

selecting (902) between the first method and the second method for scaling the transmit power of the one or more radio signals, based on the received message.

20. The method for selecting of claim 19, wherein the first method scales the transmit power of the one or more radio signals by a same value in all transmitted radio resources, and the second method scales the transmit power of the one or more radio signals belonging to at least a first group of radio resources by a first value, and the transmit power of the one or more radio signals belonging to at least a second group of radio resources by a second value.

21. The method for selecting of any of claims 19-20, further comprising scaling (903) the one or more radio signals transmitted by the second radio node (611), based on the selected method.

22. The method for selecting of any of claims 19-21 , further comprising transmitting (904) to the third radio node (671) radio signals scaled according to the selected method.

23. Computer program, comprising instructions which, when executed on at least one processor, cause the at least one processor to carry out the method according to any one of claims 19 to 22.

24. A computer-readable storage medium, having stored thereon a computer program, comprising instructions which, when executed on at least one processor, cause the at least one processor to carry out the method according to any one of claims 19 to 22.

25. A first radio node (640) configured to select a method for scaling a transmit power of one or more radio signals configured to be transmitted by a second radio node (611) to a third radio node (671), the second radio node (611) being configured to use a modulation scheme, the first radio node (640) being configured to:

obtain information about how often one or more radio signals, modulated using the modulation scheme, are used with a transmit modulation quality better than a first threshold, the one or more modulated radio signals being configured to be transmitted by the second radio node (61 1), and

select between a first method and a second method for scaling the transmit power of the one or more radio signals, based on the obtained information.

26. The first radio node (640) of claim 19, wherein the first method is configured to scale the transmit power of the one or more radio signals by a same value in all radio resources configured to be transmitted, and the second method is configured to scale the transmit power of the one or more radio signals belonging to at least a first group of radio resources by a first value, and the transmit power of the one or more radio signals belonging to at least a second group of radio resources by a second value.

27. The first radio node (640) of claim 20, wherein the one or more modulated radio signals are configured to be modulated using Higher Order Modulation, HOM, which satisfies a condition that the number of modulated symbols is above a second threshold.

28. The first radio node (640) of claim 21 , wherein the HOM is 256 QAM, the number of modulated symbols is 256 and the second threshold is 128 symbols.

29. The first radio node (640) of any of claims 19-22, wherein the transmit modulation quality of the one or more modulated radio signals is at least one of: an Error Vector Magnitude, a frequency error and a time alignment between signals from any two pair of transmit antennas.

30. The first radio node (640) of any of claims 19-23, wherein the first threshold is

determined by the first radio node (640) autonomously, or based on input received from another network node (612, 650).

31. The first radio node (640) of any of claims 19-24, wherein the information is based on at least one of: statistics of usage by the first radio node (640) of a better modulation quality, an amount of data in a buffer for transmission of the first radio node (640), an operation of a cell on/off scheme in neighboring cells to the first radio node (640), a cell deployment of the first radio node (640), and a category or capability of a receiving wireless device (671 , 672).

32. The first radio node (640) of any of claims 19-25, being further configured to send a message to at least one of: the third radio node (671), a wireless device (671 , 672), the second radio node (61 1), and another network node (611 , 612, 650), the message comprising an indication of the selected method.

33. The first radio node (640) of any of claims 19-26, being further configured to scale the one or more radio signals configured to be transmitted by the second radio node (611), based on the selected method.

34. A third radio node (671) configured to adapt a receiver configuration in the third radio node (671), the third radio node (671) being configured to:

receive a message from a first radio node (640), wherein the message comprises an indication of a selected method between a first method and a second method for scaling a transmit power of one or more radio signals configured to be transmitted by a second radio node (61 1), the second radio node (61 1) being configured to use a modulation scheme, the selected method having been selected based on information about how often one or more radio signals, modulated using the modulation scheme, are used with a transmit modulation quality better than a first threshold, the one or more modulated radio signals being configured to be transmitted by the second radio node (611), and the information being configured to be obtained by the first radio node (640); and

adapt the receiver configuration in the third radio node (671), based on the received message.

35. The third radio node (671) of claim 28, wherein the first method is configured to scale the transmit power of the one or more radio signals by a same value in all radio resources configured to be transmitted, and the second method is configured to scale the transmit power of the one or more radio signals belonging to at least a first group of radio resources by a first value, and the transmit power of the one or more radio signals belonging to at least a second group of radio resources by a second value.

36. The third radio node (671) of any of claims 28-29, being further configured to receive through the adapted receiver, radio signals from the second radio node (611), the radio signals being configured to be scaled according to the selected method.

37. The third radio node (671) of any of claims 28-30, wherein the message further comprises an amount of power scaling configured to be used by the first radio node (640).

38. The third radio node (671) of any of claims 28-31 , wherein to adapt comprises at least one of: to change a duration over which a channel estimation is valid, to select a type of reference signals to be used for channel estimation, to select a type of receiver types in the third radio node (671), and to select a duration over which a signal measurement is performed.

39. A second radio node (611) configured to select a method for scaling a transmit power of one or more radio signals configured to be transmitted by the second radio node (61 1) to a third radio node (671), the second radio node (611) being configured to use a modulation scheme, the second radio node (611) being configured to:

receive a message from a first radio node (640) configured to operate in the wireless communications network (600), wherein the message comprises an indication of a selected method between a first method and a second method for scaling the transmit power of the one or more radio signals, modulated using the modulation scheme, based on information about how often one or more modulated radio signals are used with a transmit modulation quality better than a first threshold, the one or more modulated radio signals being configured to be transmitted by the second radio node (611), and the information being configured to be obtained by the first radio node (640), and select between the first method and the second method for scaling the transmit power of the one or more radio signals, based on the received message.

40. The second radio node (61 1) of claim 33, wherein the first method is configured to scale the transmit power of the one or more radio signals by a same value in all radio resources configured to be transmitted, and the second method is configured to scale the transmit power of the one or more radio signals belonging to at least a first group of radio resources by a first value, and the transmit power of the one or more radio signals belonging to at least a second group of radio resources by a second value.

41. The second radio node (61 1) of any of claims 33-34, being further configured to scale the one or more radio signals configured to be transmitted by the second radio node (61 1), based on the selected method.

42. The second radio node (61 1) of any of claims 33-35, being further configured to transmit to the third radio node (671) radio signals configured to be scaled according to the selected method.