WO2015135178A1

WO2015135178A1 - Method, serving station apparatus, user equipment and system for sharing resource in a wireless network

Info

Publication number: WO2015135178A1
Application number: PCT/CN2014/073369
Authority: WO
Inventors: Haiming Wang
Original assignee: Nokia Technologies Oy; Nokia (China) Investment Co. Ltd
Priority date: 2014-03-13
Filing date: 2014-03-13
Publication date: 2015-09-17

Abstract

Method, serving station apparatus, user equipment and system are disclosed for sharing resource in a wireless network having a base station and a plurality of user equipments (UEs). The UEs are divided into a first and a second group, the two groups are assigned a first and a second time division duplexing (TDD) configuration respectively. The method comprising: measuring an inter-UE interference in a subframe, at which the two TDD configurations have different transmission directions; and determining a solution for resource sharing based at least partly on the inter-UE interference.

Description

METHOD, SERVING STATION APPARATUS, USER EQUIPMENT AND

SYSTEM FOR SHARING RESOURCE IN A WIRELESS NETWORK

Field of the Invention

[0001] Embodiments of the disclosure generally relate to wireless communications, and, more particularly, to resource sharing in a wireless network.

Background

[0002] Universal Mobile Telecommunications System (UMTS) is an exemplary implementation of a "third-generation" or "3G" cellular telephone technology. The

UMTS standard is specified by a collaborative body referred to as the 3 rd Generation Partnership Project (3GPP). The 3GPP has adopted UMTS as a 3G cellular radio system targeted for inter alia European markets, in response to requirements set forth by the International Telecommunications Union (rfU). The ITU standardizes and regulates international radio and telecommunications. Further enhancements to UMTS have been summarized under the Long Term Evolution (LTE) radio standard, as fourth generation (4G) technology. LTE- Advanced (LTE- A), an evolution of LTE, is being standardized in LTE Release 10 and beyond.

[0003] In order to improve spectral efficiency, multiple approaches for resource sharing have been developed. For example, some researchers from Standford University and Rice University have recently made significant progresses to achieve the practical full duplex system by using combined and advanced self-interference cancellation schemes. The full duplex transmission not only approximately doubles the throughput from the physical layer perspective, but also brings revolutionary impact to the MAC design leading to much higher throughput for future wireless communication systems. In addition, single user multiple-input and multiple-output (SU-MIMO) and multi-user multiple-input and multiple- output (MU-MIMO) have also been practical options for spectrum efficiency improvement. However, these different solutions have different requirements to operate and may have different gains in different circumstances. Therefore, it is desirable to adaptively select from the available options to maximize the gain. Summary

[0004] This summary is provided to introduce a selection of concepts in a simplified form that are further described below in the detailed description. This summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used to limit the scope of the claimed subject matter.

[0005] According to one aspect of the disclosure, it is provided a method for sharing resource in a wireless network having a base station and a plurality of user equipments (UEs). The UEs are divided into a first and a second group, the two groups are assigned a first and a second time division duplexing (TDD) configuration respectively. The method comprising: measuring an inter-UE interference in a subframe, at which the two TDD configurations have different transmission directions; and determining a solution for resource sharing based at least partly on the inter-UE interference.

[0006] According to another aspect of the present disclosure, it is provided a serving station apparatus configured to share resource in a wireless network having a plurality of user equipments (UEs). The UEs are divided into a first and a second group, the two groups are assigned a first and a second time division duplexing (TDD) configuration respectively. The apparatus comprising: UE group data configured to maintain information about the two groups and UEs in each group; group indication means configured to inform said UEs which group they are in; measurement collecting means configured to collect an inter-UE interference from at least one of the UEs; and resource sharing analytics configured to determine a solution for resource sharing based at least partly on the inter-UE interference.

[0007] According to still another aspect of the present disclosure, it is provided a serving station apparatus configured to share resource in a wireless network having a plurality of user equipments (UEs). The UEs are divided into a first and a second group, the two groups are assigned a first and a second time division duplexing (TDD) configuration respectively. The apparatus comprising: at least one processor; and at least one memory including computer program code, wherein the at least one memory and the computer program code are configured to, with the at least one processor, cause the serving station to: maintain information about the two groups and UEs in each group; inform said UEs which group they are in; collect an inter-UE interference from at least one of the UEs; and determine a solution for resource sharing based at least partly on the inter-UE interference.

[0008] According to still another aspect of the present disclosure, it is provided a user equipment (UE) configured to work in a wireless network. The UE comprises: group identification means configured to receive group indication information indicating which group the UE belongs to, wherein the UE belongs to either a first or a second group, and the two groups are assigned a first and a second time division duplexing (TDD) configuration respectively; and inter-UE interference measuring means configured to measure an inter-UE interference in a subframe, at which the two TDD configurations have different transmission directions.

[0009] According to still another aspect of the present disclosure, it is provided user equipment (UE) configured to work in a wireless network. The UE comprises at least one processor; and at least one memory including computer program code, wherein the at least one memory and the computer program code are configured to, with the at least one processor, cause the UE to:: receive group indication information indicating which group the UE belongs to, wherein the UE belongs to either a first or a second group, and the two groups are assigned a first and a second time division duplexing (TDD) configuration respectively; and measure an inter-UE interference in a subframe, at which the two TDD configurations have different transmission directions.

[0010] According to still another aspect of the present disclosure, it is provided a system for sharing resource in a wireless network, comprising: at least one above- described serving station apparatus and a plurality of above-described UEs. [0011] These and other objects, features and advantages of the disclosure will become apparent from the following detailed description of illustrative embodiments thereof, which are to be read in connection with the accompanying drawings.

Brief Description of the Drawings

[0012] Figure 1 is a simplified block diagram illustrating a wireless system according to an embodiment;

[0013] Figure 2 is an illustrative diagram showing the structure of radio frame according to an embodiment;

[0014] Figure 3 is an illustrative diagram showing the TDD configurations for UE groups according to an embodiment;

[0015] Figure 4 is an illustrative diagram depicting an example of scheduling results according to an embodiment;

[0016] Figure 5 is a flowchart depicting the process of sharing resource in a wireless network according to an embodiment;

[0017] Figure 6 is a simplified block diagram illustrating a serving station apparatus according to an embodiment; and

[0018] Figure 7 is a simplified block diagram illustrating a user equipment (UE) according to an embodiment.

Detailed Description

[0019] For the purpose of explanation, details are set forth in the following description in order to provide a thorough understanding of the embodiments disclosed. It is apparent, however, to those skilled in the art that the embodiments may be implemented without these specific details or with an equivalent arrangement. [0020] Figure 1 shows a wireless system and Figure 5 is a flowchart depicting the process of sharing resource in a wireless network according to an embodiment. While this and other embodiments below are primarily discussed in the context of a fourth generation UMTS LTE network, it will be recognized by those of ordinary skill that the disclosure is not so limited. In fact, the various aspects of this disclosure are useful in any wireless network that can benefit from the adaptive resource sharing as is described herein, such as CDMA, TDMA, FDMA, OFDMA, SC-FDMA and other networks. The terms "network" and "system" are often used interchangeably. A CDMA network may implement a radio technology such as Universal Terrestrial Radio Access (UTRA), cdma2000, etc. UTRA includes Wideband CDMA (WCDMA) and other variants of CDMA. cdma2000 covers IS-2000, IS-95 and IS- 856 standards. A TDMA network may implement a radio technology such as Global System for Mobile Communications (GSM). An OFDMA network may implement a radio technology such as Evolved UTRA (E-UTRA), Ultra Mobile Broadband (UMB), IEEE 802.11 (Wi-Fi), IEEE 802.16 (WiMAX), IEEE 802.20, Flash-OFDMA, etc.

[0021] As shown in Figure 1, the wireless system comprises a serving base station (eNodeB) 100 and a plurality of UEs 200. The solid lines with double arrows indicate desired transmissions between the UEs and the serving eNodeB on the downlink and uplink. It is well known that a cellular radio system comprises a network of radio cells each served by a transmitting station, known as a cell site or base station. The radio network provides wireless communications service for a plurality of transceivers (in most cases mobile). The network of base stations working in collaboration allows for wireless service which is greater than the radio coverage provided by a single serving base station. The individual base stations are connected by another network (in many cases a wired network, not shown), which includes additional controllers for resource management and in some cases access to other network systems (such as the Internet) or MANs. [0022] In a UMTS system, a base station is commonly referred to as a "Node B". The UMTS Terrestrial Radio Access Network (UTRAN) is the collective body of NodeBs along with the UMTS Radio Network Controllers (RNC). The user interfaces to the UTRAN via user equipment (UE), which in many typical usage cases is a cellular phone or smartphone. As used herein, the term "user equipment" (UE) includes, but are not limited to cellular telephones, smartphones, and computers, whether desktop, laptop, or otherwise, as well as mobile devices such as handheld computers, PDAs, video cameras, set-top boxes, personal media devices, or any combinations of the foregoing. Further, the term "wireless" means any wireless signal, data, communication, or other interface including without limitation Wi-Fi, Bluetooth, 3G (e.g., 3GPP, 3GPP2, and UMTS), HSDPA/HSUPA, TDMA, CDMA (e.g., IS-95A, WCDMA, etc.), FHSS, DSSS, GSM, PAN/802.15, WiMAX (802.16), 802.20, narrowband/FDMA, OFDM, PCS/DCS, analog cellular, CDPD, satellite systems, millimeter wave or microwave systems, acoustic, and infrared (i.e., IrDA).

[0023] As shown in Figure 1, the process starts at step 501 where the UEs 200 are divided into two groups (Gu and G_D) according to the nature of their transmissions. Specifically, the group G_D is composed of the UEs that have more downlink transmissions, while the group Gu is composed of the UEs that have more uplink transmissions. The grouping can be done when the UEs get registered in the system and can be updated from time to time, for example, when the upper layer demands a switch of transmission direction, at either eNodeB or UE side.

[0024] The grouping information is sent from the eNodeB to the UEs. Namely, each UE is informed which group it belongs to. In this embodiment, this is done via physical downlink control channel (PDCCH). However, it will be appreciated that there are other ways to send the grouping information to UEs, for example, by broadcasting, unicasting or multicasting, and via other channels, such as physical downlink shared channel (PDSCH), physical broadcast channel (PBCH), physical multicast channel (PMCH), etc. [0025] The two groups (Gu and G_D) are assigned with different time-division duplex (TDD) configurations. Figure 2 shows a frame structure and Figure 3 shows the TDD configurations for UE groups (Gu and G_D) according to an embodiment. In LTE, the transmission timeline is partitioned into units of radio frames 201, as shown in Figure 2. Each radio frame 201 has a predetermined duration (e.g., 10 milliseconds) and is further partitioned into 10 subframes 202 with indices of 0 through 9. Each sub-frame may include two slots and, thus, each radio frame may include 20 slots with indices of 0 through 19. The available time frequency resources in each slot may be partitioned into physical resource blocks (PRBs). Each resource block may cover N subcarriers (e.g., 12 subcarriers) in one slot.

[0026] In the embodiment, as shown in Figure 3, the group Gu is assigned a heavy uplink TDD configuration (DUUUU), while the group G_D is assigned a heavy downlink TDD configuration (DUDDD). Because of the different TDD configurations of the two groups, the subframes in each radio frame can be classified into three subsets:

• S_D, those subframes in which the two groups both have downlink transmission (e.g. subframes #0 and #5 in Figure 3);

• Su, those subframes in which the two groups both have uplink transmission (e.g. subframes #1 and #6 in Figure 3); and

• S_FD, those subframes in which the two groups have different transmission directions (e.g. subframes #2-4 and #7-9 in Figure 3).

[0027] Back to Figure 5, the process then proceeds to step 505 where inter-UE interference (IUI) is measured by at least one UE. This is done in subset S_FD- Specifically, in this embodiment, the UEs in Gu group send a sounding reference signal (SRS) or random access channel (RACH) in a S_FD subframe according to a SRS/RACH configuration. The SRS/RACH configuration may indicate the frequency resource and sequence to use, but not necessarily indicate the subframe #, which can be determined by a UE from its group and the subframe subsets. For example, the UEs in Gu group may send SRS/RACH at the first subframe in S_FD- Further, the resource for SRS/RACH may also be linked implicitly from the UE-ID allocated for the UE in Gu group. On the other hand, the UEs in G_D group measure the SRS/RACH in the corresponding subframe in subset S_FD if the report of IUI is configured. Similar to the sending UE, the subframe can be configured explicitly, or known implicitly to the measuring UE, for example always the first subframe in S_FD-

[0028] At step 510, a self-interference cancellation gain (CG) is measured. In either Gu or G_D group, a UE having full duplex (FD) capability can measure its self- interference CG in subframe subset Su- A UE in Gu group does not need to measure or report its self-interference CG in an Su subframe, unless it is triggered by eNodeB. In the meantime, a UE in G_D group can report its self-interference CG in an Su subframe when it is triggered by eNodeB or when it is requested to make a buffer status report (BSR). This will be explained in detail below. Details of self-interference and its cancelation are described, inter alia, by Choi J et al., in the article entitled "Achieving Single Channel, Full Duplex Wireless Communication" (Mobicom' 10), which is incorporated herein by reference in its entirety.

[0029] Then at step 515, a UE, either in Gu or G_D group, can conduct legacy channel state information (CSI) measurement in subframe subset SD. The CSI measurement can provide channel quality indicator (CQI) for half -duplex (HD) normal operation. Details of the legacy CSI measurement and report are described in, inter alia, 3GPP Technical Specification TS 36.213 entitled "E-UTRA, Physical layer procedures (Release 10)", which is incorporated herein by reference in its entirety.

[0030] When a UE has got the measurement, IUI, CG or CSI, as described above, it can report to the eNodeB 200 in either periodic or aperiodic manner. In aperiodic mode, measurement information is sent back to eNodeB via physical uplink shared channel (PUSCH) in response to a "CQI request" bit in an uplink resource grant sent on PDCCH. In periodic mode, the uplink control channel (PUCCH) is used to periodically send measurement information. Details of the periodic and aperiodic report are described in, inter alia, 3GPP Technical Specification TS 36.213 entitled "E-UTRA, Physical layer procedures (Release 10)", which is incorporated herein by reference in its entirety.

[0031] According to the embodiment, in addition to the legacy measurement under the LTE standard (e.g. CQI, PMI and RI), the UEs also transmit IUI and/or CG measurement information on the uplink in an aperiodic or periodic fashion, making use of the uplink channels PUSCH or PUCCH respectively.

[0032] After the relevant measurement has been reported from the UEs to the eNodeB, the process proceeds to step 520 where a resource sharing solution is determined, as shown in Figure 5. in this embodiment, there are mulitple options available for sharing resource. For example, if, in subframe n, UE1 is scheduled to send PUSCH in subframe n+4, in PRB i, then to reuse the same resource, the eNodeB has at least three options:

• Option#l: in subframe n+4, schedule another UE2 for uplink in the same resource;

• Option#2: in subframe n+4, schedule another UE3 for downlink in the same resource; and

• Option#3: in subframe n+4, schedule UE1 's downlink in the same resource.

[0033] Option#l is uplink MU-MIMO, which is supported in the current LTE standard. It increases spectrum effeciency through space-division multiplex (SDM). To enable such SDM, UE1 and UE2 has to be spatially separated. At reception side, the eNnodeB has to handle the inter-stream interference. Where a large number of UEs are in the system, there is a good chance to get a UE pair suitable for MU-MIMO operation to increase the spectrum efficiency. Details of uplink MU-MEVIO are described in, inter alia, 3GPP Technical Specification TS 36.213 entitled "E-UTRA, Physical layer procedures (Release 10)", 3GPP Technical Specification TS 36.213 entitled "E-UTRA, Physical layer procedures (Release 10)", 3GPP Technical Specification TS 36.211 entitled "Physical Channels and Modulation (Release 10)", and 3GPP Technical Specification TS 36.212 entitled " Multiplexing and channel coding (Release 10)", which are incorporated herein by reference in their entirety.

[0034] Option#2 is to implement full-duplex (FD) at eNodeB side, while UEl and UE3 still work in half-duplex (HD) mode. To enable this, UEl and UE3 have to be sufficiently apart from each other to avoid significant inter-UE interference. Compared with option#l, option#2 has the advantage of allowing multiplexing of UEs with different link directions in the same resource. This is beneficial, for example, where there is more DL traffic in the system, because the resource for UL transmission of UEl can be shared with DL transmission of UE3 when the two UEs are not close to each other, at the cost of introducing FD capability at eNB side.

[0035] The option#3 is to implement FD at both eNodeB and UE sides. Namely, both the eNB and UE have to be capable of self-interference cancellation. Compared with option#2, option#3 enables the DL and UL transmissions of UEl in the same resource. This avoids the inter-UE interference of option#2, at the cost of introducing self-interference and requiring self-interference cancellation capability at both eNB and UE sides. Moreover, option#3 can be used only when UEl has both DL and UL traffics. Details of full duplex and self-interference cancellation are described, inter alia, by Jain M et al. in the article entitled "Practical, Real-time, Full Duplex Wireless" (MobiCom' l l), by Choi J et al. in the article entitled "Achieving Single Channel, Full Duplex Wireless Communication" (Mobicom' 10), by Radunovic B et al. in the article entitled "Rethinking Indoor Wireless Mesh Design: Low Power, Low Frequency, Full-Duplex" (http://research.microsoft.com/pubs/131336/main.pdf), by Everett E et al. in the article entitled "Empowering Full-Duplex Wireless Communication by Exploiting Directional Diversity" (Asilomar 2011), and by Achaleshwar Sahai et al. in the article entitled "Pushing the limits of Full-duplex: Design and Real-time Implementation" (Rice university technical report TREE1104), which are incorporated herein by reference in their entirety.

[0036] Since the three options have different requirements and advantages, in the embodiment, the system can select from them dynamically based on factors, such as, eNodeB/UE capability, traffic, and interference, to achieve maximum gain.

[0037] According to this embodiment, it is first determined whether the UE is capable of FD operation. If yes, then all options are available; otherwise only options #1 and #2 can be selected.

[0038] Then, the system assesses each available option based on the relevant measurements and its potential gain. Specifically, for option#l, the eNodeB can assess the transmit power (TP) estimation considering the inter-stream interference as the uplink CSI and SINR are available. For option#2, the eNodeB can assess uplink TP of UEl and downlink TP of UE2, considering the inter-UE interference (obtained at step 505). For option#3, the eNodeB can assess uplink TP of UEl, and downlink TP of UEl, considering the self-interference cancellation gain (obtained at step 510).

[0039] Moreover, the grouping of UEs into Gu and G_D can also simplify the scheduling at eNodeB side. For example, in assessing option #2, the eNodeB can simply consider pairing a UE from Gu group and a UE from G_D group for eNodeB- side FD operation, rather than assessing all possible UE pairs.

[0040] Figure 4 shows an example of scheduling results according to an embodiment. As shown in Figure 4, in subframe 0, the physical resource block (PRBi) is scheduled to be downlink for both UEl and UE3, which is downlink MU-MIMO. In subframe 1, PRBi is scheduled to be uplink for both UEl and UE6, which is uplink MU-MIMO. In subframe 2, PRBi is scheduled to be both downlink and uplink for UE5, which is full duplexing at both UE and eNB sides. In subframe 3, PRBi is scheduled to be uplink for UE4 and downlink for UE2, which is eNodeB-side full duplexing. In subframe 4, PRBi is scheduled to be downlink for both UE2 and UE6, which is downlink MU-MIMO. As shown in this example, spectrum efficiency in each subframe has been improved by dynamic selection of resource sharing options.

[0041] According to the above embodiments, the subframe-subset-based measurement/report simplifies the measurement/report configurations, and reduces unnecessary reports. For example, after deriving the three subframe subsets, a UE implicitly knows where to measure the CQI, IUI or CG. For a UE in Gu, it is assumed that the UE has uplink heavy traffic and it does not know when there will be downlink traffic. In case there is only uplink traffic, it is not necessary to enable full-duplex at UE side and, thus, there is no need to report the self-interference CG. Accordingly, the self-interference CG is reported only when the eNodeB triggers it. On the other hand, for a UE in G_D, it is assumed that the UE has downlink heavy traffic. When there is uplink traffic coming, the UE knows it and, thus, can report the self- interference CG to the eNodeB together with the BSR report for uplink traffic to enable a full-duplex operation at UE side for resource saving.

[0042] According to another embodiment, the UE operation can be further simplified. This is done by simplifying the physical downlink control channel (PDCCH) detection. In the embodiment, a UE in Gu group only detects scheduling grant in subframe subset S_D- Specifically, in subframe i in S_D, the UE detects: 1) downlink grant for subframe i; 2) combined grant (grant for both uplink and downlink) for subframe n+k which is in S_FD if a self-interference CG has been reported; and 3) uplink grant for subframe n+k which is S_FD if no self-interference CG has been reported. On the other hand, a UE in G_D group detects scheduling grant in both S_D and S_FD- Specifically, in subframe i in S_D, the UE detects downlink grant for subframe i, and combined grant for subframe n+k which is in S_FD if a self-interference CG is reported. In subframe i in S_FD, the UE detects downlink grant if no self-interference CG is reported.

[0043] According to another embodiment, in order to avoid impact to legacy UEs (those UEs following release 8 or older LTE standard), the scheduling of legacy UEs is restricted to those subframes denoted as "L" in Figure 3, where there is no inter-UE interference and the legacy UEs can perform legacy CSI measurement to get accurate CSI report.

[0044] As shown in the above described embodiments, an adaptive resource sharing can be achieved with the help of UE grouping and defined UE operations in subframe subsets. Thus, the embodiments can optimize the scheduling strategies based on UE capability, self-interference CG, IUI and potential gain on spectrum efficiency. They can also reduce the work at eNodeB side and simplify the measurement configurations and UE operations.

[0045] According to an aspect of the disclosure it is provided a serving station apparatus configured to share resource in a wireless network. Figure 6 depicts a serving station apparatus (eNodeB) 100 useful in implementing the methods for resource sharing as described above. As shown in Figure 6, the serving station apparatus 100 comprises a processing device 604, a memory 605, and a radio modem subsystem 601 in operative communication with the processor 604. The radio modem subsystem 601 comprises at least one transmitter 602 and at least one receiver 603. While only one processor is illustrated in Figure 6, the processing device 604 may comprises a plurality of processors or multi-core processor(s). Additionally, the processing device 604 may also comprise cache to facilitate processing operations.

[0046] Computer-executable instructions can be loaded in the memory 605 and, when executed by the processing device 604, cause the serving station apparatus 100 to implement the above-described methods for resource sharing in the wireless network. In particular, the computer-executable instructions can cause the serving station apparatus 100 to: maintain information about the two groups (GU, GD) and UEs under each group; inform the UEs which group they are in; collect an inter-UE interference from at least one of the UEs; and determine a solution for resource sharing based at least partly on the inter-UE interference. [0047] In an embodiment, the computer-executable instructions further cause the serving station apparatus 100 to collect a self-interference CG from at least one of the UEs and determine a solution for resource sharing based at least partly on the inter- UE interference and the self-interference cancellation gain. The computer-executable instructions may further cause the serving station apparatus to collect a legacy channel state information (CSI) measurement from at least one of the UEs. The measurement and report of IUI, self-interference CG and legacy CSI have be described above.

[0048] In an embodiment, the computer-executable instructions further cause the serving station apparatus to select one scheme from the options including base- station-side full duplex, both-side full duplex, and space division multiplex. Additionally, the computer-executable instructions may further cause the serving station apparatus to pair a UE from the first group and a UE from the second group when the option of base- station- side full duplex is selected.

[0049] According to an aspect of the disclosure it is provided a serving station apparatus configured to share resource in a wireless network having a plurality of user equipments (UEs), wherein the UEs are divided into a first group and a second group, the two groups are assigned a first and a second time division duplexing (TDD) configuration respectively, the apparatus comprising: UE group data configured to maintain information about the two groups and UEs under each group; group indication means configured to inform said UEs which group they are in; measurement collecting means configured to collect an inter-UE interference from at least one of the UEs; and resource sharing analytics configured to determine a solution for resource sharing based at least partly on the inter-UE interference.

[0050] In an embodiment, the measurement collecting means is further configured to collect a self-interference cancellation gain from at least one of the UEs; and the resource sharing analytics is further configured to determine a solution for resource sharing based at least partly on the inter-UE interference and the self-interference cancellation gain. Additionally, the measurement collecting means may be further configured to collect a legacy channel state information (CSI) measurement from at least one of the UEs.

[0051] In an embodiment, the resource sharing analytics is further configured to select one scheme from the options including base- station- side full duplex, both-side full duplex, and space division multiplex. Additionally, the resource sharing analytics may be further configured to pairing a UE from the first group and a UE from the second group when the option of base- station- side full duplex is selected.

[0052] According to an aspect of the disclosure it is provided a user equipment (UE) configured to work in a wireless network. Figure 7 depicts a UE 200 useful in implementing the methods for resource sharing as described above. As shown in Figure 7, the UE 200 comprises a processing device 704, a memory 705, and a radio modem subsystem 701 in operative communication with the processor 704. The radio modem subsystem 701 comprises at least one transmitter 702 and at least one receiver 703. While only one processor is illustrated in Figure 7, the processing device 704 may comprises a plurality of processors or multi-core processor(s). Additionally, the processing device 704 may also comprise cache to facilitate processing operations.

[0053] Computer-executable instructions can be loaded in the memory 705 and, when executed by the processing device 704, cause the UE 200 to implement the above- described methods for resource sharing in the wireless network. In particular, the computer-executable instructions can cause the UE 200 to: receive group indication information indicating which group the UE belongs to, wherein the UE belongs to either a first or a second group, and the two groups are assigned a first and a second time division duplexing (TDD) configuration respectively; and measure an inter-UE interference in a subframe, at which the two TDD configurations have different transmission directions.

[0054] In an embodiment, the UE is capable of self-interference cancellation and the computer-executable instructions further cause the UE to measure a self-interference cancellation gain in a subframe, at which the two TDD configurations both have uplink transmission. Additionally, the computer-executable instructions may further cause the UE to conduct legacy channel state information (CSI) measurement in a subframe, at which the two TDD configurations both have downlink transmission.

[0055] In an embodiment, the first TDD configuration of the first group has more uplink transmission subframes and the second TDD configuration of the second group has more downlink transmission subframes. The computer-executable instructions further cause the UE to: when belonging to the first group, send a sounding reference signal (SRS) in a subframe that the first TDD configuration has uplink transmission and the second TDD configuration has downlink transmission; and, when belonging to the second group, measure the SRS in that subframe.

[0056] Additionally, the computer-executable instructions may further cause the UE to: when belonging to the first group, detect downlink grant for those subframes that the first TDD configuration has downlink transmission, combined grant for those subframes that the first and second TDD configurations have different transmission directions if a self-interference cancellation gain has been reported, and uplink grant for those subframes that the first and second TDD configurations have different transmission directions if a self -interference cancellation gain has not been reported; and, when belonging to the second group, detect downlink grant for those subframes that the second TDD configuration has downlink transmission, combined grant for those subframes that the first and second TDD configurations have different transmission directions if a self-interference cancellation gain has been reported, and uplink grant for those subframes that the first and second TDD configurations have different transmission directions if a self -interference cancellation gain has not been reported.

[0057] According to an aspect of the disclosure it is provided a user equipment (UE) configured to work in a wireless network, the UE comprising: group identification means configured to receive group indication information indicating which group the UE belongs to, wherein the UE belongs to either a first or a second group, and the two groups are assigned a first and a second time division duplexing (TDD) configuration respectively; and inter-UE interference measuring means configured to measure an inter-UE interference in a subframe, at which the two TDD configurations have different transmission directions.

[0058] In an embodiment, the UE is capable of self-interference cancellation and further comprises: self-interference cancellation gain measuring means configured to measure a self-interference cancellation gain in a subframe, at which the two TDD configurations both have uplink transmission. Additionally, the UE may further comprise: legacy measuring means configured to conduct legacy channel state information (CSI) measurement in a subframe, at which the two TDD configurations both have downlink transmission.

[0059] In an embodiment, the first TDD configuration of the first group has more uplink transmission subframes and the second TDD configuration of the second group has more downlink transmission subframes. The UE is configured to, when belonging to the first group, send a sounding reference signal (SRS) in a subframe that the first TDD configuration has uplink transmission and the second TDD configuration has downlink transmission; and, when belonging to the second group, measure the SRS in that subframe.

[0060] Additionally, the UE may be configured to: when belonging to the first group, detect downlink grant for those subframes that the first TDD configuration has downlink transmission, combined grant for those subframes that the first and second TDD configurations have different transmission directions if a self-interference cancellation gain has been reported, and uplink grant for those subframes that the first and second TDD configurations have different transmission directions if a self- interference cancellation gain has not been reported; and, when belonging to the second group, detect downlink grant for those subframes that the second TDD configuration has downlink transmission, combined grant for those subframes that the first and second TDD configurations have different transmission directions if a self- interference cancellation gain has been reported, and uplink grant for those subframes that the first and second TDD configurations have different transmission directions if a self-interference cancellation gain has not been reported.

[0061] According to an aspect of the disclosure it is provided a system for sharing resource in a wireless network, comprising an above-described serving station apparatus; and a plurality of above-described UEs.

[0062] It is noted that any of the components of the serving station apparatus and UE can be implemented as hardware or software modules. In the case of software modules, they can be embodied on a tangible computer-readable recordable storage medium. All of the software modules (or any subset thereof) can be on the same medium, or each can be on a different medium, for example. The software modules can run, for example, on a hardware processor. The method steps can then be carried out using the distinct software modules, as described above, executing on a hardware processor.

[0063] The term "computer program" or "software" is meant to include any sequence or human or machine cognizable steps which perform a function. Such program may be rendered in virtually any programming language or environment including, for example, C/C++, Fortran, COBOL, PASCAL, assembly language, markup languages (e.g., HTML, SGML, XML), and the like, as well as object-oriented environments such as the Common Object Request Broker Architecture (CORBA), Java™ (including J2ME, Java Beans, etc.), Binary Runtime Environment (BREW), and the like.

[0064] The term "storage device" is meant to 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 (a non-exhaustive list) of the storage device would include the following: 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.

[0065] In any case, it should be understood that the components illustrated herein may be implemented in various forms of hardware, software, or combinations thereof, for example, application specific integrated circuit(s) (ASICS), functional circuitry, an appropriately programmed general purpose digital computer with associated memory, and the like. Given the teachings of the disclosure provided herein, one of ordinary skill in the related art will be able to contemplate other implementations of the components of the disclosure.

[0066] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the disclosure. 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" and/or "comprising," when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of another feature, integer, step, operation, element, component, and/or group thereof.

[0067] The descriptions of the various embodiments have been presented for purposes of illustration, but are not intended to be exhaustive or limited to the embodiments disclosed. Many modifications and variations will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the described embodiments.

Claims

Claims What is claimed is:

1. A method for sharing resource in a wireless network having a base station and a plurality of user equipments (UEs), wherein said UEs are divided into a first and a second group, the two groups are assigned a first and a second time division duplexing (TDD) configuration respectively, the method comprising:

measuring an inter-UE interference in a subframe, at which the two TDD configurations have different transmission directions; and

determining a solution for resource sharing based at least partly on the inter- UE interference.

2. The method according to claim 1, further comprising:

measuring a self-interference cancellation gain in a subframe, at which the two TDD configurations both have uplink transmission;

wherein the step of determining comprises:

determining a solution for resource sharing based at least partly on the inter- UE interference and the self-interference cancellation gain.

3. The method according to claim 1 or 2, further comprising:

conducting legacy channel state information (CSI) measurement in a subframe, at which the two TDD configurations both have downlink transmission.

4. The method according to any one of claims 1 to 3, wherein the step of determining comprises:

selecting one scheme from the options including base- station- side full duplex, both-side full duplex, and space division multiplex.

5. The method according to claim 4, wherein the step of determining comprises:

pairing a UE from the first group and a UE from the second group when the option of base- station- side full duplex is selected.

6. The method according to any one of claims 1 to 3, wherein the first TDD configuration of the first group has more uplink transmission subframes and the second TDD configuration of the second group has more downlink transmission subframes;

the step of measuring inter- UE interference comprises:

in a subframe that the first TDD configuration has uplink transmission and the second TDD configuration has downlink transmission,

sending a sounding reference signal (SRS) from a UE in the first group; and measuring the SRS at a UE in the second group.

7. The method according to claim 6, wherein a UE in the first group detects downlink grant for those subframes that the first TDD configuration has downlink transmission, combined grant for those subframes that the first and second TDD configurations have different transmission directions if a self-interference cancellation gain has been reported, and uplink grant for those subframes that the first and second TDD configurations have different transmission directions if a self- interference cancellation gain has not been reported; and

a UE in the second group detects downlink grant for those subframes that the second TDD configuration has downlink transmission, combined grant for those subframes that the first and second TDD configurations have different transmission directions if a self-interference cancellation gain has been reported, and uplink grant for those subframes that the first and second TDD configurations have different transmission directions if a self-interference cancellation gain has not been reported.

8. A serving station apparatus configured to share resource in a wireless network having a plurality of user equipments (UEs), wherein the UEs are divided into a first and a second group, the two groups are assigned a first and a second time division duplexing (TDD) configuration respectively, the apparatus comprising:

UE group data configured to maintain information about the two groups and UEs in each group;

group indication means configured to inform said UEs which group they are in;

measurement collecting means configured to collect an inter-UE interference from at least one of the UEs; and resource sharing analytics configured to determine a solution for resource sharing based at least partly on the inter-UE interference.

9. The apparatus according to claim 8, wherein the measurement collecting means is further configured to collect a self-interference cancellation gain from at least one of the UEs; and the resource sharing analytics is further configured to determine a solution for resource sharing based at least partly on the inter-UE interference and the self-interference cancellation gain.

10. The apparatus according to claim 8 or 9, the measurement collecting means is further configured to collect a legacy channel state information (CSI) measurement from at least one of the UEs.

11. The apparatus according to any one of claims 8 to 10, wherein the resource sharing analytics is configured to select one scheme from the options including base- station- side full duplex, both- side full duplex, and space division multiplex.

12. The apparatus according to claim 11, wherein the resource sharing analytics is further configured to pairing a UE from the first group and a UE from the second group when the option of base- station- side full duplex is selected.

13. A serving station apparatus configured to share resource in a wireless network having a plurality of user equipments (UEs), wherein the UEs are divided into a first and a second group, the two groups are assigned a first and a second time division duplexing (TDD) configuration respectively, the apparatus comprising:

at least one processor; and

at least one memory including computer program code,

wherein the at least one memory and the computer program code are configured to, with the at least one processor, cause the serving station apparatus to: maintain information about the two groups and UEs in each group;

inform said UEs which group they are in;

collect an inter-UE interference from at least one of the UEs; and

determine a solution for resource sharing based at least partly on the inter-UE interference.

14. The apparatus according to claim 13, wherein the computer-executable instructions are further configured to, when executed by the processing device, cause the serving station apparatus to collect a self-interference cancellation gain from at least one of the UEs and determine a solution for resource sharing based at least partly on the inter-UE interference and the self-interference cancellation gain.

15. The apparatus according to claim 13 or 14, wherein the computer- executable instructions are further configured to, when executed by the processing device, cause the serving station apparatus to collect a legacy channel state information (CSI) measurement from at least one of the UEs.

16. The apparatus according to any one of claims 13 to 15, wherein the computer-executable instructions are further configured to, when executed by the processing device, cause the serving station apparatus to select one scheme from the options including base-station-side full duplex, both-side full duplex, and space division multiplex.

17. The apparatus according to claim 16, wherein the computer-executable instructions are further configured to, when executed by the processing device, cause the serving station apparatus to pair a UE from the first group and a UE from the second group when the option of base- station- side full duplex is selected.

18. A user equipment (UE) configured to work in a wireless network, the UE comprising:

group identification means configured to receive group indication information indicating which group the UE belongs to, wherein the UE belongs to either a first or a second group, and the two groups are assigned a first and a second time division duplexing (TDD) configuration respectively; and

inter-UE interference measuring means configured to measure an inter-UE interference in a subframe, at which the two TDD configurations have different transmission directions.

19. The UE according to claim 18, wherein the UE is capable of self- interference cancellation and further comprises: self-interference cancellation gain measuring means configured to measure a self-interference cancellation gain in a subframe, at which the two TDD configurations both have uplink transmission.

20. The UE according to claim 18 or 19, further comprising:

legacy measuring means configured to conduct legacy channel state information (CSI) measurement in a subframe, at which the two TDD configurations both have downlink transmission.

21. The UE according to any one of claims 18 to 20, wherein the first TDD configuration of the first group has more uplink transmission subframes and the second TDD configuration of the second group has more downlink transmission subframes;

the UE is configured to, when belonging to the first group, send a sounding reference signal (SRS) in a subframe that the first TDD configuration has uplink transmission and the second TDD configuration has downlink transmission; and, when belonging to the second group, measure the SRS in that subframe.

22. The UE according to claim 21, wherein the UE is configured to, when belonging to the first group, detect downlink grant for those subframes that the first TDD configuration has downlink transmission, combined grant for those subframes that the first and second TDD configurations have different transmission directions if a self-interference cancellation gain has been reported, and uplink grant for those subframes that the first and second TDD configurations have different transmission directions if a self-interference cancellation gain has not been reported; and,

when belonging to the second group, detect downlink grant for those subframes that the second TDD configuration has downlink transmission, combined grant for those subframes that the first and second TDD configurations have different transmission directions if a self-interference cancellation gain has been reported, and uplink grant for those subframes that the first and second TDD configurations have different transmission directions if a self-interference cancellation gain has not been reported.

23. A user equipment (UE) configured to work in a wireless network, the UE comprising:

at least one processor; and

at least one memory including computer program code,

wherein the at least one memory and the computer program code are configured to, with the at least one processor, cause the UE to:

receive group indication information indicating which group the UE belongs to, wherein the UE belongs to either a first or a second group, and the two groups are assigned a first and a second time division duplexing (TDD) configuration respectively; and

measure an inter-UE interference in a subframe, at which the two TDD configurations have different transmission directions.

24. The UE according to claim 23, wherein the UE is capable of self- interference cancellation and the computer-executable instructions are further configured to, when executed by the processing device, cause the UE to:

measure a self-interference cancellation gain in a subframe, at which the two TDD configurations both have uplink transmission.

25. The UE according to claim 23 or 24, wherein the computer-executable instructions are further configured to, when executed by the processing device, cause the UE to:

conduct legacy channel state information (CSI) measurement in a subframe, at which the two TDD configurations both have downlink transmission.

26. The UE according to any one of claims 23 to 25, wherein the first TDD configuration of the first group has more uplink transmission subframes and the second TDD configuration of the second group has more downlink transmission subframes; and the computer-executable instructions are further configured to, when executed by the processing device, cause the UE to:

when belonging to the first group, send a sounding reference signal (SRS) in a subframe that the first TDD configuration has uplink transmission and the second TDD configuration has downlink transmission; and, when belonging to the second group, measure the SRS in that subframe.

27. The UE according to claim 21, wherein the computer-executable instructions are further configured to, when executed by the processing device, cause the UE to:

when belonging to the first group, detect downlink grant for those subframes that the first TDD configuration has downlink transmission, combined grant for those subframes that the first and second TDD configurations have different transmission directions if a self-interference cancellation gain has been reported, and uplink grant for those subframes that the first and second TDD configurations have different transmission directions if a self-interference cancellation gain has not been reported; and,

28. A system for sharing resource in a wireless network, comprising:

a serving station apparatus according to any one of claims 8-17; and a plurality of user equipments (UEs) according to any one of claims 18-27.