WO2025043597A1

WO2025043597A1 - Uplink channel enhancement

Info

Publication number: WO2025043597A1
Application number: PCT/CN2023/116111
Authority: WO
Inventors: Jian Qin ZHENG; Rossella De Benedittis; Li Fan ZHANG; Bao Cai LI
Original assignee: Nokia Shanghai Bell Co Ltd; Nokia Solutions and Networks Oy
Current assignee: Nokia Shanghai Bell Co Ltd; Nokia Solutions and Networks Oy
Priority date: 2023-08-31
Filing date: 2023-08-31
Publication date: 2025-03-06
Anticipated expiration: 2026-02-28

Abstract

Embodiments of the present disclosure disclose devices, methods and apparatuses for uplink channel enhancement. In the embodiments, a network device allocates, based on an addition of a secondary cell (SCell) a first set of resources to an uplink control channel for the SCell. The first set of resources at least has been allocated to an uplink control channel for another SCell. In this way, the performance of the uplink channel can be improved.

Description

UPLINK CHANNEL ENHANCEMENT

FIELD

Embodiments of the present disclosure generally relate to the field of telecommunication, and in particular, to devices, methods, apparatuses and computer readable storage medium for the uplink channel enhancement.

BACKGROUND

With the development of communication technology, the carrier aggregation (CA) technology has been introduced to broad a bandwidth served for a terminal device. In the CA, multiple component carriers (CC) are aggregated and jointly used for transmission to/from a single terminal device. Specifically, the terminal device supporting CA can transmit or receive data transmission in multiple cells which are configured with a corresponding carrier respectively. For the terminal device, there may be one primary cell (PCell) and one or more secondary cells (SCell) in multiple cells. The PCell may be the cell to which the terminal device initially accesses, and the one or more SCells may be configured by the network for the terminal device subsequently. In addition, the network may also activate or deactivate the SCells on demand.

In addition, for enhancing the performance of communication on a cell (PCell or SCell) , the terminal device may report channel quality related information to the network for each cell serving the terminal device. Moreover, the resources for the report are dedicatedly and exclusively configured for a cell.

SUMMARY

In general, example embodiments of the present disclosure provide devices, methods, apparatuses and computer readable storage medium for the uplink channel enhancement.

In a first aspect, there is provided a network device. The network device may comprise at least one processor; and at least one memory storing instructions that, when executed by the at least one processor, cause the network device to: allocate, based on an addition of a secondary cell (SCell) , a first set of resources to an uplink control channel for the SCell. The first set of resources at least has been allocated to an uplink control channel for another SCell.

In a second aspect, there is provided a method implemented at a network device. The method comprises: allocating, based on an addition of an SCell, a first set of resources to an uplink control channel for the SCell. The first set of resources at least has been allocated to an uplink control channel for another SCell.

In a third aspect, there is provided an apparatus. The apparatus comprises: means for allocating, based on an addition of an SCell, a first set of resources to an uplink control channel for the SCell, wherein the first set of resources at least has been allocated to an uplink control channel for another SCell.

In a fourth aspect, there is provided a non-transitory computer readable medium comprising program instructions for causing an apparatus to perform at least the method according to the second aspect.

In a fifth aspect, there is provided a computer program comprising instructions, which, when executed by an apparatus, cause the apparatus at least to: allocate, based on an addition of an SCell, a first set of resources to an uplink control channel for the SCell. The first set of resources at least has been allocated to an uplink control channel for another SCell.

In a sixth aspect, there is provided a network device. The network device comprises an allocation circuitry configured to allocate, based on an addition of an SCell, a first set of resources to an uplink control channel for the SCell, wherein the first set of resources at least has been allocated to an uplink control channel for another SCell.

It is to be understood that the summary section is not intended to identify key or essential features of embodiments of the present disclosure, nor is it intended to be used to limit the scope of the present disclosure. Other features of the present disclosure will become easily comprehensible through the following description.

BRIEF DESCRIPTION OF THE DRAWINGS

Some example embodiments will now be described with reference to the accompanying drawings, where:

Fig. 1A illustrates an example network environment in which example embodiments of the present disclosure may be implemented;

Fig. 1B illustrates an example of physical uplink control channel (PUCCH) resources allocated to multiple serving cells of UEs;

Fig. 2 illustrates an example flowchart of a method for uplink channel enhancement implemented at a network device according to example embodiments of the present disclosure;

Fig. 3 illustrates an example of physical uplink control channel (PUCCH) resources allocated to multiple serving cells of UEs according to example embodiments of the present disclosure;

Fig. 4 illustrates an example flowchart of a priority based method for dynamically activating or deactivating SCells that shares the same PUCCH resources according to example embodiments of the present disclosure;

Fig. 5 illustrates an example flowchart of a method for activating an SCell according to example embodiments of the present disclosure;

Fig. 6 illustrates an example signaling process for configuring the same PUCCH resources for SCells of different UEs according to some embodiments of the present disclosure;

Fig. 7A illustrates an example of a cell capacity enhancement achieved according to some embodiments of the present disclosure;

Fig. 7B illustrates an example of a throughput gain achieved according to some embodiments of the present disclosure;

Fig. 8 illustrates an example simplified block diagram of an apparatus that is suitable for implementing embodiments of the present disclosure; and

Fig. 9 illustrates an example block diagram of an example computer readable medium in accordance with some embodiments of the present disclosure.

Throughout the drawings, the same or similar reference numerals represent the same or similar element.

DETAILED DESCRIPTION

Principle of the present disclosure will now be described with reference to some example embodiments. It is to be understood that these embodiments are described only for the purpose of illustration and help those skilled in the art to understand and implement the present disclosure, without suggesting any limitation as to the scope of the disclosure. The disclosure described herein may be implemented in various manners other than the ones described below.

In the following description and claims, unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skills in the art to which the present disclosure belongs.

References in the present disclosure to “one embodiment, ” “an embodiment, ” “an example embodiment, ” and the like indicate that the embodiment described may include a particular feature, structure, or characteristic, but it is not necessary that every embodiment includes the particular feature, structure, or characteristic. Moreover, such phrases are not necessarily referring to the same embodiment. Further, when a particular feature, structure, or characteristic is described in connection with an embodiment, it is submitted that it is within the knowledge of one skilled in the art to affect such feature, structure, or characteristic in connection with other embodiments whether or not explicitly described.

It may be understood that although the terms “first” and “second” etc. may be used herein to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from another. For example, a first element could be termed a second element, and similarly, a second element could be termed a first element, without departing from the scope of example embodiments. As used herein, the term “and/or” includes any and all combinations of one or more of the listed terms.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of example embodiments. As used herein, the singular forms “a” , “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “comprises” , “comprising” , “has” , “having” , “includes” and/or “including” , when used herein, specify the presence of stated features, elements, and/or components etc., but do not preclude the presence or addition of one or more other features, elements, components and/or combinations thereof.

As used in this application, the term “circuitry” may refer to one or more or all of the following:

(a) hardware-only circuit implementations (such as implementations in only analog and/or digital circuitry) and

(b) combinations of hardware circuits and software, such as (as applicable) :

(i) a combination of analog and/or digital hardware circuit (s) with software/firmware and

(ii) any portions of hardware processor (s) with software (including digital signal processor (s) ) , software, and memory (ies) that work together to cause an apparatus, such as a mobile phone or server, to perform various functions) and

(c) hardware circuit (s) and or processor (s) , such as a microprocessor (s) or a portion of a microprocessor (s) that requires software (e.g., firmware) for operation, but the software may not be present when it is not needed for operation.

This definition of circuitry applies to all uses of this term in this application, including in any claims. As a further example, as used in this application, the term circuitry also covers an implementation of merely a hardware circuit or processor (or multiple processors) or portion of a hardware circuit or processor and its (or their) accompanying software and/or firmware. The term circuitry also covers, for example and if applicable to the particular claim element, a baseband integrated circuit or processor integrated circuit for a mobile device or a similar integrated circuit in server, a cellular network device, or other computing or network device.

As used herein, the term “communication network” refers to a network following any suitable communication standards, such as long term evolution (LTE) , LTE-advanced (LTE-A) , wideband code division multiple access (WCDMA) , high-speed packet access (HSPA) , narrow band Internet of things (NB-IoT) and so on. Furthermore, the communications between a terminal device and a network device in the communication network may be performed according to any suitable generation communication protocols, including, but not limited to, the third generation (3G) , the fourth generation (4G) , 4.5G, the fifth generation (5G) communication protocols, 5G-A, and/or beyond. Embodiments of the present disclosure may be applied in various communication systems. Given the rapid development in communications, there will of course also be future type communication technologies and systems with which the present disclosure may be embodied. It should not be seen as limiting the scope of the present disclosure to only the aforementioned system.

As used herein, the term “network device” refers to a node in a communication network via which a terminal device accesses the network and receives services therefrom. The network device may refer to a base station (BS) or an access point (AP) , for example, a node B (NodeB or NB) , an evolved NodeB (eNodeB or eNB) , a NR NB (also referred to as a gNB) , a remote radio unit (RRU) , a radio header (RH) , a remote radio head (RRH) , a relay, a low power node such as a femto, a pico, and so forth, depending on the applied terminology and technology.

The term “terminal device” refers to any end device that may be capable of wireless communication. By way of example rather than limitation, a terminal device may also be referred to as a communication device, user equipment (UE) , a subscriber station (SS) , a portable subscriber station, a mobile station (MS) , or an access terminal (AT) . The terminal device may include, but not limited to, a mobile phone, a cellular phone, a smart phone, voice over IP (VoIP) phones, wireless local loop phones, a tablet, a wearable terminal device, a personal digital assistant (PDA) , portable computers, desktop computer, image capture terminal devices such as digital cameras, gaming terminal devices, music storage and playback appliances, vehicle-mounted wireless terminal devices, wireless endpoints, mobile stations, laptop-embedded equipment (LEE) , laptop-mounted equipment (LME) , USB dongles, smart devices, wireless customer-premises equipment (CPE) , an Internet of things (loT) device, a watch or other wearable, a head-mounted display (HMD) , a vehicle, a drone, a medical device and applications (e.g., remote surgery) , an industrial device and applications (e.g., a robot and/or other wireless devices operating in an industrial and/or an automated processing chain contexts) , a consumer electronics device, a device operating on commercial and/or industrial wireless networks, and the like. In the following description, the terms “terminal device” , “communication device” , “terminal” , “user equipment” and “UE” may be used interchangeably.

In this disclosure, the term “resources allocated to uplink control channel” may refer to resources configured for physical uplink control channel (PUCCH) or PUCCH resources. Accordingly, the terms “resources allocated to uplink control channel” , “resources configured for PUCCH” and “PUCCH resources” may be used interchangeably. In addition, the term “aset of resources” may be used interchangeably with the term “aresource set” . Without any limitation, the resource may refer to time-frequency resources in this disclosure. For example, the resource may be a physical resource block (PRB) .

In this disclosure, the serving cell of UE may include a primary cell (PCell) or a secondary cell (SCell) served for the UE. The UE may initially accesses to the network device via the PCell. If the UE needs more bandwidth to perform some traffic, the network may active an SCell for the UE on demand. In turn, the PUCCH resources are configured per serving cell of UE.

In addition, UEs need to report (for example, periodically) channel state information (CSI) for a serving cell by using at least a portion of the resources allocated to the PUCCH for the serving cell. The at least a portion of PUCCH resources for the periodic CSI (pCSI) report may be also referred to as pCSI PUCCH resources. Without any limitation, in this disclosure, the above resources allocated to uplink control channel (or PUCCH resources) may also refer to pCSI PUCCH resources.

As mentioned above, the resources for the PUCCH (or pCSI report) are dedicatedly and exclusively configured for a cell. In this case, if UE is configured or activated with a plurality of serving cells, then each of the serving cell should be configured or indicated with dedicated PUCCH resources. As such, once the CA is applied to quite some UEs and even each UE is aggregated with many CCs, more PRB resources have to be reserved to support more UEs, which will cause, for example, the resource for PUSCH is reduced. Only for discussion clarity, the resource allocation related to the current CA is further discussed as below.

CA is a key feature in LTE and 5G. Especially for 5G, the SCell number supported by a UE is increased quite many comparing with LTE to get better throughput. While with the SCell number increasing, the PUCCH resource for periodic CSI report could be one bottleneck which will limit the max UE numbers in the cell.

That is, the periodic CSI report resource must be configured for UE with RRC reconfiguration together with SCell configuration. Therefore, dedicated PUCCH resource need to be reserved for each SCell, which causes PUCCH resource bottleneck.

In turn, the aperiodic-CSI (A-CSI) -report scheme is further illustrated as below.

For CA case, with DCI triggered A-CSI report, increased DCI bits could be the limitation. In addition, A-CSI report is based on UL scheduling, to guarantee gNB gets aperiodic CSI report periodically, pure UL Grant for aperiodic CSI report is required, it requires extra UL scheduling. If it’s not guaranteed that gNB gets aperiodic CSI report periodically, it can be that aCSI report comes too late, with impacts on DL data throughput and on radio connection quality. Also, multiplex aCSI report with data on PUSCH, result in PUSCH code rate increasing and impact on PUSCH performance, require aCSI report impacts DL as well since it changes the time sequence of DL HARQ feedback.

In view of the above, no matter P-CSI or A-CSI, the reserved resources for the PUCCH per serving cell can be further optimized.

Specifically, in CA case, UE need to report, on PCell, CSI-report for all serving cells. gNB need to reserve dedicate PUCCH resource for each SCell for the UE. Accordingly, the PUCCH resource on PCell could be quite limited when there are many UEs have SCells. This will highly limit the UE number capacity of the cell. The more CA UEs in a cell or the more SCells configured to each CA UE, the less cell capacity.

For example, assuming that there are 100 pCSI PUCCH resources in a TDD cell where pCSI bundling is applied (i.e., pCSI-report for beam management and for channel state information acquisition of the same cell are multiplexed and transmitted with the same pCSI PUCCH resource) : up to 100 UEs can be admitted in the cell if each UE is non-CA UE; up to 50 UEs can be admitted in the cell if each UE is 2CC CA UE; up to 33 UEs can be admitted in the cell if each UE is 3CC CA UE; and up to 25 UEs can be admitted in the cell if each UE is 4CC CA UE and so on. The following Table 1 further shows the above assumption.

Table 1

As shown in above table, with given number of pCSI PUCCH resources, cell capacity decreased dramatically if all the attached UEs are CA UEs and allocated with dedicated pCSI PUCCH resource for each SCell.

Furthermore, considering the case that some of the UEs are CA UEs and some of the UEs are non-CA UEs and pCSI PUCCH resources have been used up in a cell. In this case, non-CA UEs may have no chance to be configured with SCell anymore. However, it is possible that the current non-CA UE is the UE who need CA most or who can get the most benefit from CA. For example, UE1 is configured with 3CC, UE2 is configured with 1CC only. In turn, UE1 has finished massive data transmission and the traffic demand of UE1 can be satisfied by only using PCell. Currently, UE2 is in high demand for CA. To configure CA to UE2, gNB has to release SCell of UE1 first to get free pCSI PUCCH resource to UE1. That is, extra RRC signaling is required and with long delay to configure CA to UE1.

On the other hand, to keep cell capacity from dropping while supporting CA with pCSI report configured in each serving cell, gNB has to reserve more pCSI PUCCH resources. More pCSI PUCCH reservation means less Physical Radio Resources (PRBs) available for uplink data transmission, i.e. for PUSCH, which impacts the cell’s UL throughput directly. For example, assuming that the cell bandwidth is 100M, SCS=30K, TDD frame structure DL: UL=4: 1, pCSI report periodicity=160 slot, 2 PRBs per pCSI PUCCH resource, 16 PRBs per slot are reserved for pCSI PUCCH, the number of pCSI PUCCH resources in total is: 160*1/5*16/2 = 256. That is, up to 256 non-CA UEs are supported in the cell. To support 256 CA UEs in the cell, extra PRBs have to be reserved for pCSI PUCCH per slot, that is, PUSCH get less PRBs to use as shown in below Table 2. The above technical issue is further discussed with reference to Fig. 1B.

Table 2

In view of the above and in order to improve the performance of a communication system, a scheme for uplink channel enhancement is provided. In this scheme, a network device allocates, based on an addition of an SCell, a first set of resources to an uplink control channel for the SCell, wherein the first set of resources at least has been allocated to an uplink control channel for another SCell.

In this way, the PUCCH resources for an SCell may be shared with or overbooked by another SCell. As such, the PUCCH resources reserved for massive CA UEs can be decreased, in order to enhance the performance of the communication system.

Principle and embodiments of the present disclosure will be described in detail below with reference to the accompanying drawings. Fig. 1A illustrates an example network environment 100 in which example embodiments of the present disclosure may be implemented. The environment 100, which may be a part of a communication network, includes terminal devices and network devices.

As illustrated in Fig. 1a, the network environment 100 may include a network device 110, a first terminal device 120, a second terminal device 130 and a third terminal device 140. Without any limitation, the terminal devices as shown in Fig. 1 may be CA enabled UEs. For example, the first terminal device 120 may be served by a PCell and one or more SCells provide by the network device 110. Furthermore, the network device 110 may activate or deactivate SCells for the terminal device 120, 130 or 140 on demand.

It is to be understood that the number of devices in Fig. 1a is given only for the purpose of illustration without suggesting any limitations. The system 100 may include any suitable number of network devices and/or terminal devices adapted for implementing embodiments of the present disclosure. Although not shown, it would be appreciated that one or more terminal devices may be located in the environment 100.

Communications in the network environment 100 may be implemented according to any proper communication protocol (s) , comprising, but not limited to, the third generation (3G) , the fourth generation (4G) , the fifth generation (5G) , 5G-Advanced or beyond (6G) , wireless local network communication protocols such as institute for electrical and electronics engineers (IEEE) 802.11 and the like, and/or any other protocols currently known or to be developed in the future. Moreover, the communication may utilize any proper wireless communication technology, comprising but not limited to: multiple-input multiple-output (MIMO) , orthogonal frequency division multiplexing (OFDM) , time division multiplexing (TDM) , frequency division multiplexing (FDM) , code division multiplexing (CDM) , Bluetooth, ZigBee, and machine type communication (MTC) , enhanced mobile broadband (eMBB) , massive machine type communication (mMTC) , ultra-reliable low latency communication (URLLC) , carrier aggregation (CA) , dual connectivity (DC) , and new radio unlicensed (NR-U) technologies.

Fig. 1B illustrates an example of physical uplink control channel (PUCCH) resources allocated to multiple serving cells of UEs.

As shown in Fig. 1B, in general, for each of the UEs 150, 160 and 170, the PUCCH resources are configured per serving cell of the corresponding UE. That is, each serving cell configured or activated for UE is configured with resources dedicated for PUCCH. In this case, as mentioned above, the network device 110 should reserve a large amount of resources for PUCCH, and this may cause data transmission to be impacted.

In example embodiments of this disclosure, a method is raised to use the PUCCH resource more efficiently to at least overcome the issues as discussed above. Specifically, the PUCCH resource can be shared by several SCells or several UEs. In turn, gNB can determine the resource is used by which UE by means of SCell activation and de-activation.

Fig. 2 illustrates an example flowchart 200 of a method for uplink channel enhancement implemented at a network device according to example embodiments of the present disclosure. For the purpose of discussion, the flowchart 200 will be described with reference to Fig. 1A. It would be appreciated that although the flowchart 200 has been described in the communication environment 100 of Fig. 1A, this flowchart 200 may be likewise applied to other communication scenarios.

In the flowchart 200, at 210, in response to an addition of an SCell, the network device 110 allocates a first set of resources to an uplink control channel for the SCell. Moreover, the first set of resources at least has been allocated to an uplink control channel for another SCell. In some embodiments, the network device 110 may predetermine the number of allocating for the same set of resources. That is, the network device 110 may (re) allocate the same set of resources for the predetermined allocating number, and the same set of resources can be allocated to uplink control channels for different SCells. In an example, there is a resource pool for the uplink control channels of a plurality of SCells. In response to the addition of the SCell, the network device 110 may select a set of resources (for example, the set of resources with index 0) from the resource pool, and allocate this set of resources to the added SCell. If the set of resources is allocated for the predetermined number of allocating times (which may be also referred to as “maximum booking number” ) , the network device 110 may select another set of resources (for example, the set of resources with index 1) from the resource pool, for example, in sequence. With the subsequent allocation for newly added SCells, the network device 110 may further select the sets of resources in the similar way.

In addition or alternatively, the network device 110 may also allocate the sets of resources in the resource pool in a pseudorandom manner. For example, the network device 110 may randomly select a set of resources from the resource pool for a plurality of SCells, and allocate the selected set of resources to the added SCell. Without any limitation, the network device 110 may adopt any other manners to allocate the set of resources which has been allocated to another added SCell. In this way, the network device 110 may re-allocate, to other SCells, the set of resources which has been allocated to a SCell, in order to decrease the amount of resources reserved for SCell uplink control channels.

In addition or alternatively, allocating the first set of resources which has been allocated may be further based on determining whether the resources allocated to uplink control channel fulfill an overbooking condition. In some embodiments, the network device 110 may determine whether resources allocated to an uplink control channel fulfill an overbooking condition. Whether fulfilling or satisfying the overbooking condition may be related to the usage status of the configured uplink control channel resources. In some embodiments, the network device 110 may detect whether a ratio between resources which have been allocated to the existing uplink control channel and total uplink control channel resources is above a threshold. If the ratio is above the threshold, the network device 110 may determine that the resources allocated to the uplink control channel fulfill the overbooking requirement. That is, when the total resources configured for PUCCH are allocated to the actual PUCCH (for example, PUCCH of added serving cells) for a certain amount, the network device 110 may determine that the overbooking condition is fulfilled when detecting that a new SCell is added. In addition, the above threshold may be configured or adjusted on demand. For example, the threshold may be determined by the customer of the communication system, i.e., configurable by customer. Without any limitation, the threshold may be dynamically adjusted based on the current resource utilization level. For example, if the communication resources are redundant, the threshold may be adjusted to be higher. Otherwise, the threshold may be adjusted to be lower.

In addition, whether fulfilling or satisfying the overbooking condition may be further related to the booking number of the resources which have been allocated, i.e., how many times these same resources have been allocated to different SCells or UEs (for example, the booking number as mentioned above) . For the clarity of discussions, this part of the overbooking condition will be discussed in the following embodiments with reference to the resource pool associated with PUCCH.

Still referring to Fig. 2, if the network device 110 determines that the resources allocated to the uplink control channel fulfill the overbooking condition (for example, the usage ratio of PUCCH resources is above the threshold and/or assuming that the above booking number based condition is also fulfilled) , the network device 110 allocates a first set of resources which has been allocated to an uplink control channel for the SCell. That is, if the overbooking condition is satisfied, the first set of resources for the PUCCH can be “shared” between the SCell and the other SCell. In this way, the PUCCH resource can be utilized efficiently.

In addition, the first set of resources may be maintained in the resource pool for a plurality of SCells. The resource pool may comprise a plurality of resource sets, and each set of the plurality of resource sets may be allocated to PUCCHs for one or more SCells. That is, each set of the plurality of resource sets may be shared by one or more SCells for p-CSI report. Furthermore, the network device 110 may further configure or maintain an attribute “the booking number” for each resource set in the resource pool. In some embodiments, the booking number of a resource set may be determined based on the number of SCells associated with the resource set. For example, the booking number of the first set of resources may be equal to the number SCells to which the first set of resources is allocated. That is, once a set of resources is (re-) allocated to a new added SCell for one time, the booking number of the set of resources is incremented by one. Accordingly, after the first set of resources is allocated to the added SCell, the booking number of the first set of resources in the resource pool may be incremented. As such, the resource set in the resource pool may be “overbooked” by different SCells more than one time.

In turn, as mentioned above, whether fulfilling or satisfying the overbooking condition may be further related to the booking number of a resource set in the resource pool. In some embodiments, the booking number of a resource set should be smaller than or equal to the maximum booking number which may be configured or fixed. In some embodiments, alternatively or in addition to the usage/utilization ratio of the PUCCH resources, the network device 110 may further detect whether there is at least one booking number which is below the maximum booking number in the resource pool. If there is at least one booking number which is below the maximum booking number, the network device 110 may determine that the resources allocated to the PUCCHs fulfill the overbooking condition. Otherwise, the network device 110 may determine that the resources cannot satisfy the overbooking condition.

That is, in some embodiments, the network device checks both the utilization ratio requirement of the PUCCH resource and the booking number. Only if the ratio of the allocated PUCCH is above the threshold and there is at least one booking number which is smaller than the maximum booking number, the network device 110 may determine that the resources allocated to the PUCCH can be overbooked or shared. With respect to the first set of resources, in an example, after determining that ratio is above the threshold, the network device 110 may search the resource pool and select the first set of resources with the booking number which is smaller than the maximum booking number. Then, the network device 110 may allocate this first set of resources to the PUCCH of the added SCell. In addition, the network device 110 further increments the booking number of the first set of resources by one. In turn, if there is another added SCell and the booking number of the first set of resources is equal to the maximum booking number, the network device 110 cannot allocate the first set of resources any more. In addition, the maximum booking number may be configurable, for example, can be specified by customer.

As a specific example of the above embodiments, while doing SCell addition in the network device 110 (for example, a gNB) , if detecting that pCSI PUCCH resource usage ratio has over a specified threshold (which may be also referred to as pCSIPucchUsageRatioThres) , gNB try to allocate pCSI PUCCH resource from above pool first, and if the pCSI resource from the pool is selected, the corresponding booking number (which may be also referred to as NumOfBooking) may be incremented (i.e., the value++) . In some embodiments, among the pCSI PUCCH resources in the pool, the pCSI PUCCH resource with smaller NumOfBooking may be preferred.

Without any limitation, the overbooking condition may also only consider the ratio requirement of the PUCCH. For example, there may be no “maximum booking number” limitation, and once the ratio of the PUCCH resource usage is above the threshold, the network device 110 always allocate the resource set for PUCCH of an added SCell from the resource pool.

In turn, if the overbooking condition cannot be fulfilled, the network device 110 may allocate a second set of resources which is not in the resource pool to uplink control channel for the SCell. In addition, the network device 110 may further include the second set of resources into the resource pool, and set the booking number of the second set of resources to be as one. As a specific example, gNB maintains a pCSI PUCCH resource pool. While doing SCell addition, the pCSI PUCCH resources newly allocated to UE for the pCSI report for SCell (s) are put into the pool and the attribute NumOfBooking of pCSI PUCCH is initialized as one (1) . As mentioned above, the pCSI PUCCH resource which attribute “NumOfBooking < maxBookingNum” may be considered as available for other UEs’ SCell.

In view of the above, a new rule is defined, when pCSI PUCCH resources usage rate is over a specified threshold (which is configurable by customer) , gNB supports pCSI resource overbooking for SCell, i.e., one pCSI resource may be shared among SCells of different UEs.

In addition, gNB may ensure that one pCSI PUCCH resource is used to feedback the channel quality of one SCell by one UE at a time, and the optimal UE and SCell is selected by the gNB. In some embodiments, for a time duration, the network device 110 may active only one of the SCells sharing the same resource set based on associated priority levels. That is, even if the same resource set is allocated to or shared by different SCells or UEs, the resource set can be only used for PUCCH of the activated SCell for the time duration. For example, the first set of resource is allocated to uplink control channels for a plurality of SCells. The network device 110 may determine a first SCell having the highest priority level from the plurality of SCells, and active the first SCell. Without any limitation, the first SCell may be above added SCell at 210 or any other SCell of SCells sharing the first set of resources.

In some embodiments, a priority level of an SCell is determined per terminal device based on at least one of: a channel quality indicator (CQI) reported on a primary cell (PCell) by a terminal device, and the SCell is added for the terminal device; a bandwidth of the SCell; an aggregated bandwidth of the terminal device, and the aggregated bandwidth comprises the bandwidth of the SCell; a number of active terminal devices in the SCell; or a demand level of the SCell related to traffic.

In a specific example, the network device 110 may maintain one new attribute “priority level (which may be also referred to as sCellActivationPriority) per SCell per UE dynamically. The ‘sCellActivationPriority’ may indicate the activation priority among different UEs, it takes both UE’s buffer size (the need of CA) , UE’s RF condition, the SCell’s load and SCell’s bandwidth (the benefit can get from CA) into consideration. Only as an example, the sCellActivationPriority’ can be calculated by the following equation (1)

where CQI_PCell represents the CQI reported by UE in PCell. BW_SCell represents bandwidth of the SCell to be activated. BW_Aggreated represents total aggregated bandwidth of the UE including the SCell to be activated. Served_{UE_SCell} represents the number of active UEs in the SCell to be activated. In addition, sCellRequired represents whether the SCell is required from traffic demand point of view. In an example, assuming that current activated SCell number is n, and corresponding SCell activation buffer threshold is sCellActivationBufferThres_n, then:

Only for discussion purposes, the priority based activation of the SCell is further discussed with reference to Fig. 4. Fig. 4 illustrates an example flowchart of a priority based method for dynamically activating or deactivating SCells that shares the same PUCCH resources according to example embodiments of the present disclosure.

As shown in Fig. 4, the periodical priority check 410 may be executed in the network device 110. For example, for the pCSI PUCCH resources which are shared among different UEs, the network device 110 may check whether the current activated SCell is with the highest ‘activationPriority’ . If the current activated SCell is not with the highest priority, the network device 110 shall deactivate this SCell.

Specifically, at 420, the network device 110 may calculate “ScellActivationPriority” per SCell per UE. After obtaining priority levels of each SCells, at 430, the network device 110 may check whether the current activated SCell is with the highest ‘activationPriority’ . If the current activated SCell is with the highest ‘activationPriority’ , the network device 110 may keep this SCell as the activated SCell. Otherwise, the network device 110 may deactivate this SCell.

Referring back to Fig. 2, if the network device 110 is to activate the first SCell, the network device 110 needs to further check whether the first set of resources is occupied currently. In some embodiments, the network device 110 may determine whether the first set of resources is used by a terminal device. If determining that the first set of resources is used by the terminal device, the network device 110 may refrain from activating the first SCell. If determining that the first set of resources is not used by the terminal device, the network device 110 may activate the first set of resources accordingly. Only for discussion purposes, this embodiment is further discussed with reference to Fig. 5.

Fig. 5 illustrates an example flowchart of a method for activating an SCell according to example embodiments of the present disclosure.

As shown in Fig. 5, while trying to activate one SCell in the network device 110, for example gNB, based on existing sCell activation scheme: buffer based, measurement based and the like, the gNB needs to check whether the pCSI PUCCH resource allocated to the SCell is already used by other UEs or not. If it’s already used by other UEs, gNB does not activate the SCell. If the pCSI PUCCH resource is not used by other UEs and the SCell is with the highest sCellActivationPriority among the SCells using the same pCSI PUCCH resource, gNB may activate the SCell.

Specifically, at 510, the network device 110 performs regular Scell activation checking, for example buffer-based Scell activation, measurement-based Scell activation and the like. At 520, the network device 110 determines whether the SCell activation criterion checking is passed. If passed, the flowchart proceeds to 530. Otherwise, the network device 110 cannot active the first SCell. At 530, the network device 110 determines whether the first set of resources (or pCSI PUCCH resource) is used by other UE’s activated SCell. If the first set of resources is used by other UE’s activated SCell, the flowchart proceeds to 50 and the network device 110 cannot activate the first SCell. Otherwise, the flowchart proceeds to 540, the network device 110 may check whether the first SCell is with the highest priority level as mentioned above. Then, if the first SCell is of the highest priority level, the flowchart proceeds to 550, and the network device 110 activates the first SCell. Otherwise, the network device 110 cannot activate the SCell.

Referring back to Fig. 2, in the way as discussed above, the number of CA UEs in a cell with given number of pCSI PUCCH resources can be increased (i.e. the impact of CA configuration on cell capacity is mitigated) . Furthermore, in the CA UEs sharing the same pCSI PUCCH resource, gNB can select the CA UE who requires SCell the most or select the CA UE who can get the most benefit from SCell.

Fig. 3 illustrates an example of physical uplink control channel (PUCCH) resources allocated to multiple serving cells of UEs according to example embodiments of the present disclosure. For the purpose of discussion, the flowchart 200 will be described with reference to Fig. 1A.

Compared to the SCell PUCCH resource allocation in Fig. 1b, Fig. 3 shows that the PUCCH resources for SCells of UE 120, UE 130 and UE 140 can be shared in PUCCH resource pool. In an example, the UE-1 and UE -2 may share the same set of resources for PUCCH associated with SCell. In turn, the network device 110 may activate the SCell of UE-1 or the SCell of UE-2 based on the rule as mentioned above. In this way, the PUCCH resources can be utilized efficiently and the impact on data transmission can be mitigated.

Fig. 6 illustrates an example signaling process 600 for configuring the same PUCCH resources for SCells of different UEs according to some embodiments of the present disclosure.

As shown in Fig. 6, by means of the control plane (CPlane 110-2) of the network device 110 (for example, gNB 110) , the network device 110 may configure 610 a set of resources for PUCCH to different UEs (for example, the first terminal device 120) using a radio resource control (RRC) (re) configuration procedure. Meanwhile, the pCSI PUCCH can be overbooked, i.e., the set of resources can be similarly configured to another terminal device, for example, the terminal device 130. In turn, by means of the user plane (UPlane 110-1) of the gNB 110, gNB 110 may activate or deactivate 620 the SCell of the terminal device 120 or another SCell of the terminal device 130 using medium access control (MAC) control element (CE) message. In this way, the overbooked pCSI PUCCH resource can be only used in one UE’s one SCell at a time at most.

The following simulation results show the benefits of the above embodiments with respect to the cell capacity and the cell throughput.

Fig. 7A illustrates an example of a cell capacity enhancement achieved according to some embodiments of the present disclosure.

As shown in Fig. 7A, in the case that the above scheme is applied, the columns (for example, the column 720) shows the capacity multiples in different CA situations and the line 710 shows the achieved gain. That is, with the fixed PUCCH resource, the cell capacity decline due to CA can be mitigated. Specifically, the UE number capacity gain is achieved based on assumption: maxBookingNum=3, and threshold for ratio (or pCSIPucchUsageRatioThres) = 50%. Table 3 further shows the comparison between the existing PUCCH allocation and the scheme as discussed above.

Table 3

In this way, in the case that supporting a given number of CA UEs in a cell, the PRB resources occupied by PUCCH are reduced, and more PRB resources can be used by PUSCH correspondingly. As a result, it’s beneficial to UL throughput in PCell.

Fig. 7B further shows the throughput gain achieved by using the above scheme. The gain is achieved under the following assumption: thecell bandwidth is 100M, subcarrier spacing (SCS) =30K, time division duplex (TDD) frame structure DL: UL=4: 1, pCSI report periodicity=160 slot, 2 PRBs per pCSI PUCCH resource, 16 PRBs per slot are reserved for pCSI PUCCH, and maxBookingNum=3. Table 4 further shows the UL throughput gain in different CA situations.

Table 4

The benefits can be further understood by considering the following facts: UE with burst traffic who doesn’t have a high demand of throughput always; and UE with better RF condition can get more throughput from CA. With more CA UEs configured in a cell, the CA UE who needs SCell the most or the CA UE who can get the most throughput from SCell can be selected by gNB dynamically without extra RRC signaling. In this way, a better UE experience and cell performance can be achieved.

In some embodiments, an apparatus capable of performing any of the method 200 (for example, the network device 110) may include means for determining, based on an addition of a secondary cell (SCell) , whether resources allocated to an uplink; and means for allocating, based on determining that the resources fulfill the overbooking condition, a first set of resources to an uplink control channel for the SCell, wherein the first set of resources at least has been allocated to an uplink control channel for another SCell.

In some embodiments, the apparatus may further include means for allocating, based on determining that the resources fail to fulfill the overbooking condition, a second set of resources to the uplink control channel for the SCell; means for including the second set of resources into a resource pool for a plurality of SCells, and wherein the resource pool comprises a plurality of sets of resources allocated to uplink control channels for the plurality of SCells; and means for setting the booking number of the second set of resources to be as one.

In some embodiments, the apparatus may further include means for incrementing the booking number of the first set of resources in a resource pool for a plurality of SCells.

In some embodiments, the means for determining whether the resources fulfill the overbooking condition includes: means for detecting whether a ratio between resources which have been allocated to the uplink control channel and total uplink control channel resources is above a threshold; means for determining, based on the ratio is above the threshold, that the resources allocated to the uplink control channel fulfill the overbooking requirement; and means for determining, based on the ratio is not above the ratio threshold, that the resources allocated to the uplink control channel fail to fulfill the overbooking requirement.

In some embodiments, the means for determining whether the resources fulfill the overbooking condition includes: means for detecting, in a resource pool for a plurality of SCells, whether there is at least one booking number which is below the maximum booking number; means for determining, based on detecting that there is the at least one booking number which is below the maximum booking number, that the resources fulfill the overbooking condition; and means for determining, based on detecting that there is no booking number which is below the maximum booking number, that the resources fail to fulfill the overbooking condition.

In some embodiments, the means for allocating the first set includes means for selecting, from a resource pool for a plurality of SCells, the first set resources with the booking number which is below the maximum booking number.

In some embodiments, the maximum booking number is configurable. In some embodiments, the first set of resources is allocated to uplink control channels for a plurality of SCells, and the apparatus may further include: means for determining a first SCell having the highest priority level from the plurality of SCells; and means for activating the first SCell.

In some embodiments, a priority level of the SCell is determined per terminal device based on at least one of the following: a channel quality indicator (CQI) reported on a primary cell (PCell) by a terminal device, wherein the SCell is added for the terminal device; a bandwidth of the SCell; an aggregated bandwidth of the terminal device, wherein the aggregated bandwidth comprises the bandwidth of the SCell; a number of active terminal devices in the SCell; or a demand level of the SCell related to traffic.

In some embodiments, the apparatus may further include means for determining whether a priority level of the first SCell is the highest among the plurality of SCells periodically; and means for deactivating the first SCell based on determining that the priority level of the first SCell is not the highest.

In some embodiments, the means for activating the first set of resources includes means for determining whether the first set of resources is used by a terminal device; means for refraining, based on determining that the first set of resources is used by the terminal device, from activating the first SCell; and means for activating the first SCell based on determining that the first set of resources is not used by the terminal device.

In some embodiments, the allocation of the first set of resource to different terminal devices is configured by a radio resource control (RRC) or downlink control information (DCI) message.

In some embodiments, the first set of resources is used by a terminal device for transmitting a periodic-channel status information (pCSI) report associated with the SCell in a physical uplink control channel (PUCCH) .

Fig. 8 is a simplified block diagram of a device 800 that is suitable for implementing embodiments of the present disclosure. The device 800 may be provided to implement the communication device, for example the network device 110 as shown in Fig. 1A. As shown, the device 800 includes one or more processors 810, one or more memories 840 coupled to the processor 810, and one or more transmitters and/or receivers (TX/RX) 840 coupled to the processor 810.

The TX/RX 840 is for bidirectional communications. The TX/RX 840 has at least one antenna to facilitate communication. The communication interface may represent any interface that is necessary for communication with other network elements.

The processor 810 may be of any type suitable to the local technical network and may include one or more of the following: general purpose computers, special purpose computers, microprocessors, digital signal processors (DSPs) and processors based on multicore processor architecture, as non-limiting examples. The device 800 may have multiple processors, such as an application specific integrated circuit chip that is slaved in time to a clock which synchronizes the main processor.

The memory 820 may include one or more non-volatile memories and one or more volatile memories. Examples of the non-volatile memories include, but are not limited to, a read only memory (ROM) 824, an electrically programmable read only memory (EPROM) , a flash memory, a hard disk, a compact disc (CD) , a digital video disk (DVD) , and other magnetic storage and/or optical storage. Examples of the volatile memories include, but are not limited to, a random access memory (RAM) 822 and other volatile memories that will not last in the power-down duration.

A program 830 includes executable instructions that are executed by the associated processor 810. The program 830 may be stored in the ROM 824. The processor 810 may perform any suitable actions and processing by loading the program 930 into the RAM 822.

The embodiments of the present disclosure may be implemented by means of the program so that the device 800 may perform any process of the disclosure as discussed with reference to Figs. 2 to 7. The embodiments of the present disclosure may also be implemented by hardware or by a combination of software and hardware.

In some embodiments, the program 830 may be tangibly contained in a readable storage medium which may be included in the device 800 (such as in the memory 820) or other storage devices that are accessible by the device 800. The device 800 may load the program 830 from the storage medium to the RAM 822 for execution. The storage medium may include any types of tangible non-volatile storage, such as ROM, EPROM, a flash memory, a hard disk, CD, DVD, and the like. Fig. 9 shows an example of the storage medium 900 in form of CD or DVD. The storage medium has the processor instructions 830 stored therein.

Generally, various embodiments of the present disclosure may be implemented in hardware or special purpose circuits, software, logic or any combination thereof. Some aspects may be implemented in hardware, while other aspects may be implemented in firmware or software which may be executed by a controller, microprocessor or other computing device. While various aspects of embodiments of the present disclosure are illustrated and described as block diagrams, flowcharts, or using some other pictorial representations, it is to be understood that the block, apparatus, system, technique or method described herein may be implemented in, as non-limiting examples, hardware, software, firmware, special purpose circuits or logic, general purpose hardware or controller or other computing devices, or some combination thereof.

The present disclosure also provides at least one program product tangibly stored on a non-transitory readable storage medium. The program product includes executable instructions, such as those included in program modules, being executed in a device on a target real or virtual processor, to carry out flowchart 200 as described above with reference to Fig. 2 to Fig. 7. Generally, program modules include routines, programs, libraries, objects, classes, components, data structures, or the like that perform particular tasks or implement particular abstract data types. The functionality of the program modules may be combined or split between program modules as desired in various embodiments. Machine-executable instructions for program modules may be executed within a local or distributed device. In a distributed device, program modules may be located in both local and remote storage media.

Program code for carrying out methods of the present disclosure may be written in any combination of one or more programming languages. These program codes may be provided to a processor or controller of a general purpose computer, special purpose computer, or other programmable data processing apparatus, such that the program codes, when executed by the processor or controller, cause the functions/operations specified in the flowcharts and/or block diagrams to be implemented. The program code may execute entirely on a machine, partly on the machine, as a stand-alone software package, partly on the machine and partly on a remote machine or entirely on the remote machine or server.

In the context of the present disclosure, the program codes or related data may be carried by any suitable carrier to enable the device, apparatus or processor to perform various processes and operations as described above. Examples of the carrier include a signal, readable storage medium, and the like.

The readable medium may be a readable signal medium or a readable storage medium. A readable storage medium may include but not limited to an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any suitable combination of the foregoing. More specific examples of the readable storage medium would include an electrical connection having one or more wires, a portable computer diskette, a hard disk, a random-access memory (RAM) , a read-only memory (ROM) , an erasable programmable read-only memory (EPROM or Flash memory) , an optical fiber, a portable compact disc read-only memory (CD-ROM) , an optical storage device, a magnetic storage device, or any suitable combination of the foregoing. The term “non-transitory, ” as used herein, is a limitation of the medium itself (i.e., tangible, not a signal) as opposed to a limitation on data storage persistency (e.g., RAM vs. ROM) .

Further, while operations are depicted in a particular order, this should not be understood as requiring that such operations be performed in the particular order shown or in sequential order, or that all illustrated operations be performed, to achieve desirable results. In certain circumstances, multitasking and parallel processing may be advantageous. Likewise, while several specific implementation details are contained in the above discussions, these should not be construed as limitations on the scope of the present disclosure, but rather as descriptions of features that may be specific to particular embodiments. Certain features that are described in the context of separate embodiments may also be implemented in combination in a single embodiment. Conversely, various features that are described in the context of a single embodiment may also be implemented in multiple embodiments separately or in any suitable sub-combination.

Although the present disclosure has been described in languages specific to structural features and/or methodological acts, it is to be understood that the present disclosure defined in the appended claims is not necessarily limited to the specific features or acts described above. Rather, the specific features and acts described above are disclosed as example forms of implementing the claims.

Claims

A network device comprising

at least one processor; and

at least one memory storing instructions that, when executed by the at least one processor, cause the network device at least to:

allocate, based on an addition of a secondary cell (SCell) , a first set of resources to an uplink control channel for the SCell, wherein the first set of resources at least has been allocated to an uplink control channel for another SCell.
The network device of claim 1, wherein allocating the first set of resources is based on determining that resources allocated to an uplink control channel fulfill an overbooking condition.
The network of claim 2, wherein the first device is caused to determine whether the resources fulfill the overbooking condition by detecting whether a ratio between resources which have been allocated to the uplink control channel and total uplink control channel resources is above a threshold, and wherein the network device is further caused to:

determine, based on the ratio is above the threshold, that the resources allocated to the uplink control channel fulfill the overbooking requirement; or

determine, based on the ratio is not above the ratio threshold, that the resources allocated to the uplink control channel fail to fulfill the overbooking requirement.
The network device of claim 2 or 3 wherein the first device is caused to determine whether the resources fulfill the overbooking condition by detecting, in a resource pool for a plurality of SCells, whether there is at least one booking number which is below the maximum booking number, and the network device is further caused to:

determine, based on detecting that there is the at least one booking number which is below the maximum booking number, that the resources fulfill the overbooking condition; or

determine, based on detecting that there is no booking number which is below the maximum booking number, that the resources fail to fulfill the overbooking condition.
The network device of any of claims 1 to 4, wherein the network device is further caused to:

increment the booking number of the first set of resources in a resource pool for a plurality of SCells.
The network device of any of claims 1 to 5, wherein the network device is further caused to:

allocate, based on determining that the resources fail to fulfill an overbooking condition, a second set of resources to the uplink control channel for the SCell;

include the second set of resources into a resource pool for a plurality of SCells, and wherein the resource pool comprises a plurality of sets of resources allocated to uplink control channels for the plurality of SCells; and

set the booking number of the second set of resources to be as one.
The network device of claim 5 or 6, wherein the booking number of a set of resources in the resource pool is determined based on the number of SCells associated with the set of resources.
The network device of any of claims 1 to 7, wherein the first set of resources is allocated to uplink control channels for a plurality of SCells, and wherein the network device is further caused to:

determine a first SCell having the highest priority level from the plurality of SCells; and

activate the first SCell.
The network device of any of claims 1 to 8, wherein a priority level of the SCell is determined per terminal device based on at least one of the following:

a channel quality indicator (CQI) reported on a primary cell (PCell) by a terminal device, wherein the SCell is added for the terminal device;

a bandwidth of the SCell;

an aggregated bandwidth of the terminal device, wherein the aggregated bandwidth comprises the bandwidth of the SCell;

a number of active terminal devices in the SCell; or

a demand level of the SCell related to traffic.
The network device of claim 8 or 9, wherein the network device is further caused to:

determine whether a priority level of the first SCell is the highest among the plurality of SCells periodically; and

deactivate the first SCell based on determining that the priority level of the first SCell is not the highest.
The network device of any of claims 8 to 10, wherein the network device is caused to activate the first set of resources by:

determining whether the first set of resources is used by a terminal device;

refraining, based on determining that the first set of resources is used by the terminal device, from activating the first SCell; and

activating the first SCell based on determining that the first set of resources is not used by the terminal device.
The network device of any of claims 1 to 11, wherein the allocation of the first set of resource to different terminal devices is configured by a radio resource control (RRC) or downlink control information (DCI) message.
The network device of any of claims 1 to 12, wherein the first set of resources is used by a terminal device for transmitting a periodic-channel status information (pCSI) report associated with the SCell in a physical uplink control channel (PUCCH) .
A method comprising:

allocating, based on an addition of a secondary cell (SCell) , a first set of resources to an uplink control channel for the SCell, wherein the first set of resources at least has been allocated to an uplink control channel for another SCell.
An apparatus comprising:

means for allocating, based on an addition of a secondary cell (SCell) , a first set of resources to an uplink control channel for the SCell, wherein the first set of resources at least has been allocated to an uplink control channel for another SCell.
A non-transitory computer readable medium comprising program instructions stored thereon for performing at least the method of claim 14.