HK1178366B - Signalling report transmission in carrier aggregation - Google Patents

Description

Signaling report transmission in carrier aggregation

Technical Field

The invention relates to signaling report transmission in carrier aggregation. In particular, the present invention relates to buffer status (bufferstatus) and power headroom report (powerheadroomreport) transmission in carrier aggregation.

Background

In the signaling reports standardized in E-UTRAN (evolved universal terrestrial radio access network) version 8, Buffer Status Reports (BSR) and Power Headroom Reports (PHR) are to support uplink packet scheduling and link adaptation. The BSR is used to inform the eNB (evolved node B) of the amount of data available for transmission in the UE (user equipment) buffer. The PHR brings information about how close to its maximum transmission power capacity the UE is working, and is therefore important for the eNB to be able to estimate the experienced SINR (signal to interference plus noise ratio) when the UE is allocated a certain transmission bandwidth. The BSR is typically used by the eNB to select an appropriate transport block size, while the PHR is typically used to select an appropriate Modulation and Coding Scheme (MCS).

E-UTRAN, release 10, introduced Carrier Aggregation (CA), in which two or more Component Carriers (CCs) are aggregated in order to support a wider transmission bandwidth up to 100MHz and for spectrum aggregation. In CA, a UE may be configured to aggregate different numbers of CCs originating from the same eNB and having possibly different bandwidths in UL (uplink) and DL (downlink). The principle of carrier aggregation is illustrated in fig. 1, which fig. 1 shows the system bandwidth of advanced LTE (long term evolution) comprising 5 × 20MHz component carriers. A 3GPP (third generation partnership project) release 8 UE is assumed to be served by a separate CC, while a release 10 terminal may be configured to receive or transmit simultaneously on multiple aggregated CCs in the same TTI (transmission time interval).

In CA, component carriers configured for a UE may be dynamically enabled/disabled by means of a MAC (media access control) control element. For an eNB to obtain updated knowledge of the UE's buffer status and power headroom when activation/deactivation of CCs occurs, the eNB has to force PHR-reported PRC (radio resource control) connection reconfiguration. The reconfiguration of the PHR report is a direct trigger for the PHR, but also an indirect trigger for the BSR, since it triggers an RRC response in the uplink, which is considered to be a high priority data arrival and thus triggers the BSR.

That is, the BSR is triggered when (1) high priority data arrives, (2) periodic reporting, or (3) padding (padding) occurs that is large enough to accommodate the BSR. The PHR is triggered when (1) the path loss changes, (2) the periodic reporting, or (3) the reconfiguration of the reporting.

Disclosure of Invention

The present invention aims to provide immediately an eNB as follows: the eNB has updated knowledge of the UE's buffer status and power headroom when activation/deactivation of CCs occurs.

This is achieved by an apparatus, a method and a computer program product as defined in the appended claims.

According to an embodiment of the present invention, a user equipment prepares a signaling report in response to receiving a control element for enabling/disabling a component carrier to be used by the user equipment for communication in a cellular communication network system, and transmits the signaling report.

Accordingly, when activation/deactivation of CCs occurs, an eNB may be provided with a signaling report from a UE without having to perform RRC connection reconfiguration.

Drawings

The invention will be described by embodiments of the invention with reference to the accompanying drawings, in which:

fig. 1 shows a basic diagram of component carriers to form the system bandwidth of LTE-advanced;

fig. 2 shows a schematic block diagram illustrating the structure of a UE according to an embodiment of the present invention; and

fig. 3 shows a signaling diagram illustrating signaling between a UE, an eNB, and an E-UTRAN according to an embodiment of the present invention.

Detailed Description

Referring to fig. 2, a User Equipment (UE) 10 includes a processor 11, a memory 12, and a transceiver 13 connected via a bus 14. The UE10 may be compatible with release 10E-UTRAN.

The memory 12 may store programs and the transceiver 13 may be a suitable Radio Frequency (RF) transceiver coupled to one or more antennas (not shown) for bidirectional wireless communication with the eNB over one or more wireless links.

The terms "connected," "coupled," or any variant thereof, mean any connection or coupling (direct or indirect) between two or more elements, and may encompass the presence of one or more intermediate elements between two elements that are "connected" or "coupled" together. The coupling or connection between the elements may be physical, logical, or a combination thereof. As used herein, two elements may be considered to be "connected" or "coupled" together using one or more wires, cables, and printed electrical connections, as well as using electromagnetic energy, such as electromagnetic energy having wavelengths in the radio frequency range, microwave band, and optical zones (visible and invisible), as non-limiting examples.

The programs stored in the memory 12 may include program instructions that, when executed by the processor 11, enable the UE10 to operate in accordance with the exemplary embodiments of this invention, as described in detail below. Inherent in the processor 11 is a clock for enabling synchronization between the various devices, the clock being used for transmission and reception within the appropriate time intervals and time slots required, since the scheduling grant (scheduling grant) and the granted resources/subframes are time dependent. The transceiver 13 includes a transmitter and a receiver, and inherent in both the transmitter and the receiver is a modulator/demodulator commonly referred to as a modem.

In general, exemplary embodiments of the invention may be implemented by computer software as follows: the computer software is stored in the memory 12 and is executable by the processor 11 of the UE10, or exemplary embodiments of the invention may be implemented in hardware, or in any or all of the illustrated devices, by software and/or firmware and combinations of hardware.

In general, the various embodiments of the UE10 can include, but are not limited to, mobile stations, cellular telephones, Personal Digital Assistants (PDAs) having wireless communication capabilities, portable computers having wireless communication capabilities, image capture devices such as digital cameras having wireless communication capabilities, gaming devices having wireless communication capabilities, music storage and playback appliances having wireless communication capabilities, internet appliances permitting wireless internet access and browsing, as well as portable units or terminals that incorporate combinations of such functions.

The memory 12 may be any type of memory suitable to the local technical environment and may be implemented using any suitable data storage technology, such as semiconductor-based memory devices, magnetic memory devices and systems, optical memory devices and systems, fixed memory and removable memory. The processor 11 may be any type of processor suitable to the local technical environment, and the processor 11 may include one or more of a general purpose computer, a special purpose computer, a microprocessor, a Digital Signal Processor (DSP), and a processor based on a multi-core processor architecture, as non-limiting examples.

Embodiments of the invention may be practiced with various components, such as integrated circuit modules. The design of integrated circuits is basically a highly automated process. Complex and powerful software tools are available for converting a logic layer design into a semiconductor circuit design ready to be etched and formed on a semiconductor substrate.

Programs, such as those provided by Synopsys, Inc. of mountain View, san Jose, Calif. automatically route and locate components on a semiconductor chip using well established design rules and libraries of pre-stored design modules. Once the design for a semiconductor circuit has been completed, the resulting design, in a standardized electronic format (e.g., Opus, GDSII, or the like) may be transmitted to a semiconductor fabrication facility or "fab" for fabrication.

According to an embodiment of the present invention, the processor 11 of the UE10 prepares a signaling report in response to receiving a control element for enabling/disabling a component carrier to be used by the UE10 for communication in the cellular communication network system; and the transceiver 13 sends the signaling report. The UE10 may receive a control element for activation/deactivation from the E-UTRAN (e.g., from an eNB of the E-UTRAN with which the UE10 is currently communicating) via the transceiver 13. The transceiver 13 may send the signaling report to the eNB with which the UE10 is currently communicating.

The signaling reports sent by the transceiver 13 may support uplink packet scheduling and link adaptation for the UE 10. The signaling report may include a buffer status report and/or a power headroom report.

The control element for enabling/disabling may be a medium access control element and may comply with a MAC protocol. The transceiver 13 may send the signaling report via a medium access control element complying with the MAC protocol.

The control element for activation/deactivation may be a control element for activating a component carrier and/or a control element for deactivating a component carrier. The component carriers may include at least one of the component carriers configured for use by the UE 10.

Thus, according to embodiments of the present invention, new triggers for PHR and BSR are introduced: activation/deactivation of CCs. Since the activation/deactivation of the CC is performed through the MAC control element, the new trigger may also be described as receiving a MAC control element for activation/deactivation. The trigger may be limited to activation only, and thus exclude deactivation. It is also possible to further limit the triggering to a subset of configured CCs. Such restrictions may be different for BSR and PHR. For example, the PHR may be triggered when any CC is enabled and disabled, i.e., when a MAC control element for enabling/disabling is received, and the BSR may be triggered only when enabled.

Fig. 3 shows a signaling diagram illustrating signaling between a UE10, an eNB20, and an E-UTRAN30, according to an embodiment of the present invention.

In step 1, the UE10 receives a control element for enabling/disabling a component carrier to be used by the UE10 for communication in the cellular communication network system. According to the embodiment shown in fig. 3, the cellular communication system comprises an E-UTRAN 30. The UE10 may receive a control element for activation/deactivation from the E-UTRAN30 (e.g., the eNB20 with which the UE10 is currently communicating). According to the embodiment shown in fig. 3, the control element for enabling/disabling is a medium access control element.

Upon receiving the control element, the UE10 prepares a signaling report in step 2. The signaling report may support uplink packet scheduling and link adaptation for UE10 by eNB 20. According to the embodiment shown in fig. 3, the signaling report comprises a BS/PH report.

In step 3, the UE10 sends the BS/PH report to the eNB 20. According to the embodiment shown in fig. 3, the BS/PH report is transmitted via a medium access control element.

As mentioned above, the control element for enabling/disabling may include a control element for enabling a component carrier and/or a control element for disabling a component carrier, and the component carrier may include at least one of the component carriers configured for use by the UE 10. There may be different triggers for BSR and PHR, e.g., PHR may be prepared and transmitted upon receiving MAC control elements for enabling and/or disabling any CC, while UE10 prepares and transmits a BSR upon receiving MAC control elements for enabling only. The trigger may also be limited to a subset of configured CCs.

According to an aspect of the invention, a device, such as the UE10, comprises preparing means for preparing a signaling report in response to receiving a control element for activating/deactivating a component carrier to be used by the device for communication in the cellular communication network system, and transmitting means for transmitting the signaling report. The preparing means may comprise a processor 11 and the transmitting means may comprise a transceiver 13.

The signaling report may support uplink packet scheduling and link adaptation for the device and/or may include a buffer status report and/or a power headroom report.

The control element for enabling/disabling may be a medium access control element and/or the transmitting means may transmit the signaling report via a medium access control element.

The control element for enabling/disabling may comprise at least one of the group of: a control element for enabling component carriers and a control element for disabling component carriers, and the component carriers may include at least one of the component carriers configured to be used by the device.

It is to be understood that the above description is illustrative of the invention and is not to be construed as limiting the invention. Various modifications and applications may occur to those skilled in the art without departing from the true spirit and scope of the invention as defined by the appended claims.

Claims (12)

1. An apparatus for signaling report transmission, comprising:

a processor configured to prepare a signaling report; and

a transceiver configured to transmit the signaling report,

it is characterized in that

The transceiver is configured to receive a control element for enabling/disabling component carriers to be used by the device for communication in a cellular communication network system; and

the processor is configured to trigger preparation of the signaling report by receipt of the control element.

2. The device of claim 1, wherein the signaling report supports uplink packet scheduling and link adaptation for the device and/or the signaling report comprises a buffer status report and/or a power headroom report.

3. The device of claim 1, wherein the control element for enabling/disabling is a media access control element and/or the transceiver is configured to send the signaling report via a media access control element.

4. The device of claim 1, wherein the control element for enabling/disabling comprises at least one of the group of: a control element for enabling the component carrier and a control element for disabling the component carrier; and wherein the component carriers comprise at least one of the component carriers configured to be used by the device.

5. A method for signaling report transmission, comprising:

preparing a signaling report; and

the signaling report is sent out, and the signaling report is sent out,

it is characterized by comprising:

receiving a control element for enabling/disabling component carriers to be used by a device for communication in a cellular communication network system,

wherein receipt of the control element triggers preparation and sending of the signaling report.

6. The method of claim 5, wherein the signaling report supports uplink packet scheduling and link adaptation for the device and/or the signaling report comprises a buffer status report and/or a power headroom report.

7. The method according to claim 5, wherein the control element for enabling/disabling is a medium access control element and/or said transmitting comprises transmitting said signaling report via a medium access control element.

8. The method of claim 5, wherein the control element for enabling/disabling comprises at least one of the group of: a control element for enabling the component carrier and a control element for disabling the component carrier; and wherein the component carriers comprise at least one of the component carriers configured to be used by the device.

9. An apparatus for signaling report transmission, comprising:

means for enabling preparation of a signaling report; and

means for enabling the sending of said signaling report,

it is characterized by comprising:

means for enabling reception of a control element for enabling/disabling component carriers to be used by a device for communication in a cellular communication network system,

means for enabling reception of the control element to trigger preparation and sending of the signaling report.

10. The device of claim 9, wherein the signaling report supports uplink packet scheduling and link adaptation for the device and/or the signaling report comprises a buffer status report and/or a power headroom report.

11. The apparatus according to claim 9, wherein the control element for enabling/disabling is a medium access control element and/or the transmitting comprises transmitting the signaling report via a medium access control element.

12. The device of claim 9, wherein the control element for enabling/disabling comprises at least one of the group of: a control element for enabling the component carrier and a control element for disabling the component carrier; and wherein the component carriers comprise at least one of the component carriers configured to be used by the device.