JP2013516817A - Multi-antenna resource allocation method for uplink channel sounding in wireless communication system - Google Patents

Abstract

A method for allocating multi-antenna resources for uplink channel sounding in a wireless communication system is provided.
A method for allocating multi-antenna resources for uplink channel sounding in a wireless communication system is provided. The base station (eNB) first selects a number of sounding reference signal (SRS) parameters. Then, eNB determines each selected SRS parameter of the 1st antenna of user apparatus (UE) which has a plurality of antennas. The determined parameters are jointly encoded into a first set of parameters using multiple signaling bits. The eNB transmits the signaling bit of the first antenna to the UE and does not transmit the additional signaling bit of another antenna. The UE receives the signaling bit of the SRS resource assignment of the first antenna and derives a second set of parameter combinations for the second antenna based on a predetermined rule. Implicit multi-antenna signaling SRS resource allocation makes it easy for the eNB to allocate SRS resources to different antennas of different UEs with reduced overhead.
[Selection] Figure 7

Description

  This application was filed on August 11, 2010, with provisional application number 61/293416 entitled “Sounding Channel Design for LTE-A,” filed on January 8, 2010, and August 11, 2010. US Patent Provisional Application No. 61/372658 entitled “Signaling Method for Rel-10 SRS,” claims priority under 35 USC § 119. Which is incorporated herein by reference.

  The present invention relates to wireless network communication, and more particularly to sounding channel resource allocation and signaling in an LTE-A system.

  Orthogonal frequency division multiple access (OFDMA) is a multi-user version of orthogonal wave frequency division multiplexing (OFDM) digital modulation technology. However, in wireless OFDMA systems, multipath is a universally undesired propagation phenomenon in which radio signals reach the receiving antenna by two or more paths. Signal changes in amplitude or phase due to multipath are also referred to as channel responses. The transmission technology, its transmitter, utilizes the channel response between the transmitter and receiver and is also referred to as closed loop transmission technology. During multi-input multi-output (MIMO) applications, closed-loop transmission technology is more robust than open-loop MIMO technology.

  One way to provide channel information to the transmitter is to use an uplink (UL) sounding channel. Channel sounding allows a mobile station (also called user equipment (UE)) to transmit a sounding reference signal (SRS) on the uplink channel and a base station (also called eNodeB) to estimate the UL channel response. It is a signal transduction mechanism. Channel sounding is usually normal in a time division duplex (TDD) system, assuming uplink and downlink channel correlation. In TDD systems, UL transmission frequency bandwidth includes DL transmission frequency bandwidth, so UL channel sounding is based on channel state information (CSI) measured by SRS, closed-loop SU / MU-MIMO can be enabled. UL channel sounding also enables UL closed-loop MIMO transmission in both TDD and frequency division duplex (FDD) systems. For example, the eNodeB selects the optimal precoding weights (vectors / matrices) used for the UE based on the CSI measured by the SRS, and the UE performs closed loop SU / MU-MIMO in UL transmission. Can be executed. In the TDD system, UL channel sounding is also used for frequency selective scheduling, and eNodeB schedules the UE to its optimal frequency band during downlink and uplink transmissions.

  Two types of SRS are defined in the 3GPP LTE-A wireless communication system. A first type of periodic SRS (p-SRS) is used to acquire long-term channel information. The period of p-SRS is usually long (up to 320ms), reducing overhead. The p-SRS parameter is arranged by high-layer radio resource control (RRC), installation time is long (for example, 15-20 ms), and flexibility is low. For uplink MIMO supported in Release 10, closed-loop spatial multiplexing requires a large amount of p-SRS resources, especially when the number of UEs increases. The second type of aperiodic SRS (ap-SRS) is a new feature introduced in Release 10. Ap-SRS is triggered by the uplink grant via the physical downlink control channel (PDCCH). Once triggered, the UE transmits a sounding sequence at a predetermined location. Ap-SRS supports multi-antenna sounding used for uplink MIMO. Ap-SRS is more flexible than p-SRS and can use residual resources that are not used by p-SRS. The problem facing LTE sounding is how to effectively allocate SRS resources to multiple antennas and how to effectively communicate ap-SRS parameters via uplink grants. .

  According to a first novel aspect, a method for uplink channel sounding resource allocation in a wireless communication system is provided. The base station (eNB) first selects a number of sounding reference signal (SRS) parameters. The eNB then determines the deviation set used for each selected SRS parameter and jointly encodes the selected quantity of SRS parameters using a number of signaling bits. The signaling bit is transmitted to the user equipment (UE) to perform uplink sounding signal transmission. Based on system requirements, certain unwanted parameter combinations are filtered (filtered) and only necessary parameter combinations are reserved, limiting the quantity of signaling bits to a predetermined quantity.

  In one example, signaling bits are included in the downlink control information (DCI) and are used to trigger aperiodic SRS (ap-SRS) by the physical downlink control channel (PDCCH). In one example, the quantity of signaling bits is equal to 2 and the optional parameters include SRS bandwidth and SRS frequency domain location. In another example, the number of signaling bits is equal to 2 and the optional parameters include a transmission comb option and a cyclic shift option. By jointly coding selected SRS parameters, the eNB can dynamically allocate multiple ap-SRS parameters (not just one parameter) and resources used for each UE with high flexibility and efficiency. Can do.

  According to a second aspect, there is provided a method for multi-antenna resource allocation for uplink channel sounding in a wireless communication system. The base station (eNB) first selects a number of sounding reference signal (SRS) parameters. Then, eNB determines each selected SRS parameter used for the 1st antenna of user apparatus (UE) which has a plurality of antennas. Using the multiple signaling bits, the determined parameters are jointly encoded into a first set of parameter combinations. The eNB transmits the signaling bit used for the first antenna to the UE and does not transmit the additional signaling bit used for another antenna. The UE receives signaling bits used for SRS resource allocation of the first antenna and derives a second set of parameter combinations used for the second antenna based on a predetermined rule.

  In one example, the selective parameters include a cyclic shift (CS) option and a transmission comb option used for the SRS code sequence. The eNB multiplexes different antennas of different UEs in the CS domain, and the different antennas in the CS domain are distributed at equal intervals with the maximum possible CS interval. In one example, signaling bits are transmitted over a radio control channel (RCC) and place periodic SRS (p-SRS). In another example, signaling bits are included in the downlink control information (DCI) and are transmitted over the physical downlink control channel (PDCCH) to trigger an aperiodic SRS (ap-SRS). Signaling SRS resource allocation for implicit multiple antennas makes it easy for eNBs to allocate SRS resources to different antennas of different UEs with reduced overhead.

  Other embodiments and advantages are described in the detailed description below. This summary is not intended to define the invention. The invention is defined by the claims.

The accompanying drawings illustrate embodiments of the invention, in which like numerals refer to like elements.
FIG. 2 is a diagram illustrating uplink channel sounding used for downlink and uplink closed-loop MIMO transmission of a wireless communication system according to one novel aspect. 1 shows an LTE-A wireless communication system with uplink channel sounding according to one novel aspect. FIG. FIG. 6 is a flowchart of a joint coding method used for ap-SRS parameters by eNB according to one novel aspect. It is a figure which shows the uplink channel sounding using ap-SRS by the joint encoding / decoding in a LTE-A radio | wireless communications system. It is a figure which shows the 1st specific example of the signaling method of the uplink channel sounding using joint encoding. It is a figure which shows the 2nd specific example of the signal transmission method of the uplink channel sounding using joint encoding. FIG. 6 is a flowchart of an implicit signaling method used for multi-antenna SRS resource allocation by an eNB according to one novel aspect. It is a figure which shows the implicit signaling method used for the multi-antenna SRS resource allocation in a LTE-A radio | wireless communications system. It is a figure which shows the 1st specific example of the implicit signal transmission used for the multi-antenna SRS resource allocation during LTE sounding. It is a figure which shows the 2nd specific example of the implicit signal transmission used for the multi-antenna SRS resource allocation during LTE sounding.

  Reference may describe in detail some embodiments of the invention, examples of which will be illustrated in the accompanying drawings.

  FIG. 1 is a diagram illustrating uplink channel sounding used for downlink and uplink closed-loop MIMO transmission in a wireless communication system according to one novel aspect. In a wireless communication system, a base station (also referred to as eNB) and a mobile station (also referred to as user equipment (UE)) communicate with each other by transmitting and receiving data mounted in continuous frames. Each frame includes a number of downlink (DL) subframes used for eNB and transmits data to the UE, and a number of uplink (UL) subframes used for UE and transmits data to the eNB. In the example of FIG. 1, the eNB jointly encodes a number of selected sounding reference signal (SRS) parameters, and transmits the uplink grant in DL subframe DL # 1 of frame 11 (frame N), Allocate SRS resources. Once triggered by the uplink grant, the UE decodes the SRS parameters and transmits the sounding signal on the sounding channel assigned in UL subframe UL # 3 of the subsequent frame 12 (frame N + K1). The eNB receives the sounding signal and performs uplink channel estimation based on the received sounding signal. During another subsequent frame 13 (frame N + K1 + K2), the eNB uses DL closed-loop transmission technology, closed-loop MU-MIMO or closed-loop SU-MIMO, which is selected based on channel state information (CSI) obtained from the sounding channel. And transmit data in DL subframe DL # 2. In addition, UE transmits data by UL subframe UL # 1 using UL closed-loop transmission technology notified by eNB, for example, closed-loop MIMO precoding. According to one novel aspect, a selected quantity of SRS parameters are jointly encoded, and the SRS parameters can be communicated from the eNB to the UE more effectively and with reduced overhead by means of an uplink grant.

  FIG. 2 is a diagram illustrating an LTE-A wireless communication system 20 with uplink channel sounding according to one novel aspect. The LTE-A system 20 includes a user apparatus UE21 and a base station eNB22. UE 21 includes a memory 31, a processor 32, an information decoding module 33, an SRS and sounding channel assignment module 34, and a transceiver 35 coupled to an antenna 36. Similarly, eNB 22 includes a transceiver 41 coupled to memory 41, processor 42, information encoding module 43, channel estimation module 44, and antenna 46. Referring to the above and FIG. 1, the base station eNB22 and the user apparatus UE21 communicate with each other by transmitting and receiving data mounted in successive frames. Each frame includes a number of DL subframes and a number of UL subframes. For uplink sounding, the eNB 22 arranges SRS parameters and allocates SRS resources by transmitting jointly coded signaling information to the UE 21 in the DL subframe. Based on the signaling information, the UE 21 decodes the SRS parameter, sends the sounding signal back to the eNB 22 through the sounding channel in the UL subframe, and uses it for uplink channel estimation. In one or more examples, the functions shown in the uplink sounding process are performed by different modules in hardware, software, firmware, or a combination thereof. The functions described above may be performed by the same module or each by a different module.

  In the 3GPP LTE-A system, two types of SRS are defined for uplink channel sounding. A first type of periodic SRS (p-SRS) is used to acquire long-term channel information. Periodic p-SRS is generally long (up to 320 ms). The p-SRS parameters are arranged by high-layer radio resource control (RRC), the arrangement time is long (for example, 15-20 ms delay), and the flexibility is low. The second type of aperiodic SRS (ap-SRS) is dynamically triggered by the uplink grant from the eNB. The uplink channel sounding shown in FIG. 1 is an example of sounding using ap-SRS. Once triggered, the UE transmits a sounding signal to the eNB at a predetermined position.

  In the 3GPP LTE-A system, two types of SRS parameters are defined, and p-SRS or ap-SRS parameters are arranged. The first type of cell specific parameter includes SRS bandwidth allocation and SRS subframe allocation. Cell specific parameters are used to define the entire SRS resource allocated to the cell served by the eNB. The second type of UE-specific parameters are SRS bandwidth, SRS hopping bandwidth, Frequency Domain Position, SRS location index, number of antenna ports, Transmission Comb, and cyclic Includes shift (CS: Cyclic Shift). UE-specific parameters are used to define SRS resource allocation for each independent UE. Since p-SRS and ap-SRS share the entire SRS resource, the cell-specific parameters of p-SRS are reused for ap-SRS. However, UE-specific parameters used for ap-SRS are different from p-SRS. Can be used.

  Ap-SRS is a new feature introduced in Release 10 that supports multi-antenna sounding used for uplink MIMO. Ap-SRS is more flexible than p-SRS and can use residual resources that are not used by p-SRS. Traditionally, p-SRS parameters are arranged by RRC. However, for dynamic triggering and placement of ap-SRS parameters, the use of higher layer RRC is not efficient due to the long latency. Therefore, it is desirable to trigger ap-SRS and install UE-specific parameters by a faster physical layer signaling method. In one example, ap-SRS is triggered by a physical downlink control channel (PDCCH) to provide additional flexibility. More specifically, a new n-bit region is added to the downlink control information (DCI) format X to modify the UE-specific parameters used for ap-SRS. However, because of the PDCCH coverage, the number n should not be too large. In the current 3GPP LTE-A system, for example, the numerical value n is determined to be 2. In one novel aspect, a joint coding method is used, and a selected quantity of SRS parameters are jointly coded with a new n-bit region in DCI format X and transmitted from the eNB to the UE via the PDCCH. The

  FIG. 3 is a flowchart of a method for joint encoding of ap-SRS parameters performed by an eNB according to one novel aspect. The eNB first determines which SRS parameters are jointly encoded (step 37). Another unselected SRS parameter is placed directly by the RRC. Subsequently, the eNB determines a deviation set used for each selected parameter (step 38). In general, only deviation values are used and rearranged because the value satisfies the parameter 0 <= x <N, the deviation values are selected from the set {a, b, ..., c} and c < N. The deviation set is arranged by RRC. By using the deviation set, if x + y> = 0, the possible rearrangement value of the parameter is ((x + y) mod N), or if x + y <0, ((N + x + y) mod N), y is the value of the deviation set. By using a deviation set for each selected parameter, the number of parameter combinations can be reduced. For example, it has two parameters 0 <= x1 <2 and 1 <= x2 <3. It is assumed that the deviation set is {0, 1} for the parameter x1 and the deviation set is {0} for the parameter x2. Thus, the total parameter combinations for x1 and x2 include two possible combinations: {(x1 mod 2), (x2 mod 3)} and {((x1-1) mod 2), (x2 mod 3 )}. As a result, only one bit is required to encode the two combinations of parameters x1 and x2. During step 39, the eNB lists all possible parameter combinations and filters the combinations based on system requirements, and only the required parameter combinations are in the n-bit DCI domain of signaling. Are jointly encoded. In order to achieve a preferred PDCCH coverage, another unwanted parameter combination is discarded due to the limited number of signaling bits (eg, n = 2).

  FIG. 4 is a diagram illustrating an uplink channel sounding process by joint encoding / decoding using ap-SRS in the LTE-A system 20. Since cell-specific SRS parameters of p-SRS are reused for ap-SRS in LTE-A systems, it is necessary to select only UE-specific parameters for joint coding of ap-SRS. For example, as shown in Table 40 of FIG. 4, joint coding is performed with all UE-specific SRS parameters. Thereafter, a deviation set is determined for each selected parameter. For example, a full set is selected for each UE-specific SRS parameter. Then, on the eNB side, based on the selective parameters and deviation set, eNB 22 lists all possible parameter combinations and only n bits are used for encoding the combination, so based on system requirements, Filter only those required combinations. For example, if a UE requires high speed transmission and the request requires a large transmission bandwidth, the sounding bandwidth must also be large to estimate the corresponding bandwidth channel. As a result, combinations of small sounding bandwidth parameters should be discarded. On the UE side, UE21 receives the signaling bit and decodes the selective parameter. As shown in FIG. 4, based on the decoded parameters, the UE 21 assigns a sounding channel 48 in the radio resource block 47 and transmits a sounding signal 49 through the sounding channel 48.

  FIG. 5 is a diagram illustrating a first specific example of an uplink channel sounding signal transmission method using joint coding. In the example of FIG. 5, the eNB 51 rearranges the UE-specific ap-SRS parameters of the UE 52, UE 53, and UE 54 using the PDDCH 50 using two signaling bits (n = 2). As shown in Tables 55, 56 and 57, two UE-specific parameters are selected, one is the SRS bandwidth (eg, BW) and the other is the frequency domain location (eg, TONE). Two signaling bits indicate four states, including three states with three sets of parameter combinations and one state that does not trigger ap-SRS. Each of the three states represents a single parameter combination of SRS bandwidth and frequency domain position. For example, as shown in Table 55, for UE52, State 1 shows BW = p0 and TONE = k0, State 2 shows BW = p1 and TONE = k1, and State 3 shows BW = p2 and TONE = k2. State 4 indicates that it is not activated. Similarly, Table 56 and Table 57 show different states representing different parameter combinations for UE 53 and UE 54, respectively.

  FIG. 6 is a diagram illustrating a second specific example of the uplink channel sounding signaling method using joint coding. In the example of FIG. 6, the eNB 61 resets UE-specific ap-SRS parameters of the UE 62 and the UE 63 by the PDDCH 60 using two signaling bits (n = 2). As shown in Tables 64 and 65, two UE-specific parameters are selected, one is a cyclic shift option (eg, CS) and the other is a transmission comb (eg, COMB). As in FIG. 5, the two signaling bits indicate four states, including three sets of three states of CS and COMB parameter combinations and one state that does not trigger ap-SRS. For example, for UE62, State 1 shows CS = cs1 and COMB = 0, State 2 shows CA = cs2 and COMB = 0, and State 3 shows CS = cs3 and COMB = 0, as shown in Table 64. State 4 indicates not activated. Similarly, the different states shown in Table 65 represent different parameter combinations of CS and COMB for UE63. As can be seen from the above example, the joint coding of the selected SRS parameters allows the eNB to dynamically relocate ap-SRS parameters and resources to each UE with high flexibility and efficiency. it can.

  During 3GPP LTE-A Release 10, multi-antenna sounding supports uplink MIMO. During multi-antenna sounding, the UE transmits a sounding signal from each antenna, and the eNodeB determines the optimal precoding weight (vectors / matrices) used for each antenna UE based on the CSI measured by the sounding signal. Selectively, the UE can perform closed-loop MIMO for uplink transmission on each antenna. Therefore, for uplink MIMO, multi-antenna SRS resource allocation requires that SRS resources be allocated to each antenna of each UE. For each antenna, two important SRS parameters placed by the RRC message include a cyclic shift (CS) option and a transmission comb option. In current LTE systems, 8 CS options are provided to generate 8 orthogonal Zadoff-Chu (ZC) sounding sequences and 2 transmission combs are provided to switch frequency tones in the sounding channel . As a result, the RRC message carries 4 bits and places these 2 parameters on each antenna. If SRS resources are clearly allocated antenna-by-antenna, the signaling overhead increases linearly with the increase in antenna quantity. According to one novel aspect, an implicit multi-antenna SRS resource assignment is submitted to reduce such signaling overhead.

FIG. 7 is a flowchart of an implicit signaling method used for multi-antenna SRS resource allocation by an eNB according to one novel aspect. The eNB first determines which SRS parameters are jointly encoded and used for multi-antenna resource allocation (step 71). For example, the eNB selects a cyclic shift (CS) option and a transmission comb option and uses them for joint coding. Subsequently, the eNB determines a first set of parameter combinations used for the specific antenna of the UE (step 72). For example, the first set of parameter combinations used for the first antenna is a specific CS option and a specific transmission comb option (eg, CS ₁ = 1, comb ₁ = 0). The first set of parameters is encoded using a number of signaling bits (eg, 3 bits are used for CS and 1 bit is used for comb). During step 73, the eNB transmits signaling bits to the UE. In general, different sets of parameter combinations for different antennas of the same UE are derived based on the same signaling bits as the predetermined rule. For example, if the first set of parameters used for a particular antenna is transmissionComb and cyclicShift, the kth set of parameters for the kth antenna is comb _k = (transmissionComb + α _k ) mod 2, and CS _k = (cyclicShift + β _k ) mod 8 As a result, only one combination of parameters used for one antenna is required to be encoded and transmitted to a UE having multiple antennas. The UE may derive another set of parameter combinations to be used for another antenna based on a predetermined rule. Predetermined rules (eg, α _k and β _k ) are known on the UE side, and the predetermined rules are fixed or arranged by RRC.

  FIG. 8 is a diagram illustrating an implicit signaling method for multi-antenna SRS resource allocation in the wireless LTE-A system 80. The wireless LTE-A system 80 includes a base station (eNB) 81 and two user apparatuses UE82 and UE83. UE 82 and UE 83 each have two antennas. For a specific antenna (eg, generally the first antenna) of each UE, the eNB 81 determines the setting of the SRS parameter combination and encodes the parameter combination using multiple signaling bits. For example, the signaling bit 84 used for the antenna 1 of the UE 82 indicates CS = 0 and comb = 0, and the signaling bit 85 used for the antenna 1 of the UE 83 indicates CS = 1 and comb = 1. Thereafter, signaling bits 84 and 85 are transmitted to UE 82 and UE 83, respectively. In the implicit signaling method, the eNB 81 arranges the second antenna of each UE without transmitting extra signaling bits. Instead, UE 82 and UE 83 derive the combination of SRS parameters used for their second antennas based on the same signaling bits and predetermined rules. For example, UE 82 determines the combination of parameters used for its second antenna as CS = 4 and comb = 0, and UE 83 sets the combination of parameters used for its second antenna as CS = 5 and comb = 1. To decide.

  In this implicit signaling method, UE 82 transmits a sounding signal SRS1 with a Zadoff-Chu code sequence of CS = 0 over a sounding channel 86 having comb = 0 (eg, having an odd frequency tone position). The UE 82 also transmits a sounding signal SRS2 with a Zadoff-Chu code sequence of CS = 4 over the same sounding channel 86 with comb = 0. Similarly, UE 83 transmits a sounding signal SRS3 with a Zadoff-Chu code sequence of CS = 1 over a sounding channel 87 having comb = 1 (eg, having even frequency tone positions). The UE 83 also transmits a sounding signal SRS4 with a Zadoff-Chu code sequence of CS = 5 via the same sounding channel 87 with comb = 1. Such an implicit signaling method is used for both p-SRS and ap-SRS resource allocation. For the arrangement of p-SRS, the eNB transmits a signaling bit by RCC. For the ap-SRS trigger, as shown in FIG. 6, the eNB transmits the signaling bit included in the DCI through the PDCCH.

FIG. 9 is a diagram illustrating a first specific example of implicit signaling of multi-antenna SRS resource allocation by an eNB in a wireless communication system. In the example of FIG. 9, implicit signaling is based on the following predetermined rules:
comb _k = (transmissionComb + α _k ) mod 2
CS _k = (cyclicShift + β _k ) mod 8
Where:
α0 = α1 = α2 = α3 = 0
For 1TX (1 antenna), β0 = 0
For 2TX (2 antennas), β0 = 0 and β1 = 4
For 4TX (4 antennas), β0 = 0, β1 = 4, β2 = 2, and β3 = 6
Table 91 in the upper part of FIG. 9 shows SRS resource allocations for UE0 and UE1, and UE0 and UE1 include two antennas (for example, a first antenna TX0 and a second antenna TX1). UE0 receives signaling information from an eNB that allocates SRS parameters having transmissionComb = 0 and cyclicShift = 0. Based on this signaling information and predetermined rules, UE0 derives the following SRS parameters used for sounding signal transmission:
For TX0, CS0 = 0 and Comb0 = 0
For TX1, CS1 = 4 and Comb1 = 0
Similarly, UE1 receives signaling information from an eNB that allocates SRS parameters having transmissionComb = 1 and cyclicShift = 1. Based on this signaling information and predetermined rules, UE0 derives the following SRS parameters used for sounding signal transmission:
For TX0, CS0 = 0 and Comb0 = 0
For TX1, CS1 = 4 and Comb1 = 0

Table 92 below FIG. 9 shows SRS resource allocation used for UE0 and UE1, and UE0 and UE1 have four antennas. As shown in Table 91, UE0 and UE1 receive the same signaling information from the eNB used for SRS resource allocation. Based on signaling information and predetermined rules, the following SRS parameters are derived by UE0 and UE1 used for sounding signal transmission:
For UE0:
CS0 = 0, CS1 = 4, CS2 = 2, and CS3 = 6
Comb0 = Comb1 = Comb2 = Comb3 = 0
For UE1:
CS0 = 1, CS1 = 5, CS2 = 3, and CS3 = 7
Comb0 = Comb1 = Comb2 = Comb3 = 1

  FIG. 10 is a diagram illustrating a second specific example of implicit signaling of multi-antenna SRS resource allocation by an eNB in a wireless communication system. The implicit signaling in FIG. 10 and the description in FIG. 9 are based on the same predetermined rules. However, in the example of FIG. 10, different antennas of different UEs are uniformly distributed along the CS domain with the maximum possible CS interval. For UE0, as shown in Table 101, the four antennas (TX0-TX3) of UE0 are evenly distributed with CS = 1, 3, 5, and 7. For UE0 and UE1, as shown in Table 102, the four antennas of UE0 (TX0-TX3) and the two antennas of UE1 (TX0-TX1) are CS = 0, 1, 3, 4, 5, And 7 is evenly distributed. For UE0, UE1, and UE2, as shown in Table 103, 4 antennas for UE0 (TX0-TX3), 2 antennas for UE1 (TX0-TX1), and 2 antennas for UE2 (TX0-TX1) Antennas are uniformly distributed at CS = 0, 1, 2, 3, 4, 5, 6 and 7. With this scheme, it is easy for the eNB to multiplex multiple different antennas from different UEs in the CS domain with reduced overhead. Optimal orthogonality between sounding signals from different antennas of different UEs is maintained.

  In the present invention, preferred embodiments have been disclosed as described above. However, the present invention is not limited to the present invention, and any person who is familiar with the technology can use various methods within the spirit and scope of the present invention. Variations and moist colors can be added, so the protection scope of the present invention is based on what is specified in the claims.

Claims (20)

A method of resource allocation used for a sounding channel in a wireless communication system, the method comprising:
Selecting a number of parameters from a plurality of sounding reference signal (SRS) parameters;
Each selected parameter used for the first antenna of the user equipment (UE) is determined, and the determined parameter is jointly encoded into a first set of parameter combinations using a number of signaling bits. And transmitting the signaling bits used for the first antenna from the base station to the UE, and a second set of parameter combinations used for the second antenna of the UE is derived from the signaling bits Process,
A method comprising the steps of:   The combination of the second set of parameters used for the second antenna of the UE is derived based on a predetermined rule and does not transmit additional signaling bits used for the second antenna. The method described.   The base station determines a combination of a plurality of parameters used for a plurality of UEs having a plurality of antennas, and only one set of parameter combinations is used for a specific antenna of each UE. Item 2. The method according to Item 1.   The method of claim 1, wherein the selective parameters include a cyclic shift (CS) option of a SRS code sequence and a transmission comb option.   The method of claim 4, wherein different antennas of different UEs are multiplexed in a CS domain, and the different antennas are distributed equally in the CS domain with a maximum CS interval.   The method according to claim 1, wherein the base station transmits the signaling bit through a radio control channel (RCC) to arrange periodic SRS (p-SRS).   The base station transmits a signaling bit included in downlink control information (DCI) by a physical downlink control channel (PDCCH) to trigger an aperiodic SRS (ap-SRS). The method according to claim 1. A base station,
Information coding using multiple signaling bits to jointly encode a selected quantity of sounding reference signal (SRS) parameters used for the first antenna of the user equipment (UE) into a first set of parameter combinations module,
A transceiver that transmits the signaling bits to the UE, and wherein a second set of parameters used for the second antenna of the UE is derived from the signaling bits, and the first and the first of the UE, respectively. Channel estimation is performed based on first and second sounding signals transmitted from two antennas, and the first and second sounding signals are based on a combination of the first and second sets of parameters, respectively. Channel estimation module,
A base station comprising:   The combination of the second set of parameters used for the second antenna of the UE is derived based on a predetermined rule and does not transmit additional signaling bits used for the second antenna. Base station described in.   The base station determines a combination of a plurality of parameters used for a plurality of UEs having a plurality of antennas, and only one set of parameter combinations is used for a specific antenna of each UE. Item 9. The base station according to Item 8.   The base station of claim 8, wherein the selective parameters include a cyclic shift (CS) option of a SRS code sequence and a transmission comb option.   The base station according to claim 11, wherein different antennas of different UEs are multiplexed in a CS domain, and the different antennas are evenly distributed in the CS domain with a maximum CS interval.   The base station according to claim 8, wherein the base station performs periodic SRS (p-SRS) by transmitting the signaling bit through a radio control channel (RCC).   The base station transmits a signaling bit included in downlink control information (DCI) by a physical downlink control channel (PDCCH) to trigger an aperiodic SRS (ap-SRS). The base station according to claim 8. A method for implementing a sounding channel in a wireless communication system, the method comprising:
Receiving a number of signaling bits from a base station by a user equipment (UE);
Decoding the signaling bits into a first set of sounding reference signal (SRS) parameter combinations used for the first antenna of the UE;
Deriving a second set of SRS parameter combinations to be used for the second antenna of the UE based on the same signaling bits, and based on the first set of SRS parameter combinations, from the first antenna, Transmitting a first sounding signal, and transmitting a second sounding signal from the second antenna based on a combination of the second set of SRS parameters;
A method comprising the steps of:   The UE derives a combination of the second set of parameters used for the second antenna based on a predetermined rule and does not receive additional signaling bits used for the second antenna. 15. The method according to 15.   The method of claim 15, wherein the first set of parameter combinations includes a cyclic shift (CS) option of a SRS code sequence and a transmission comb option.   The method of claim 17, wherein different antennas of different UEs are multiplexed in a CS domain, and the different antennas are evenly distributed in the CS domain with a maximum CS interval.   The method of claim 15, wherein the UE receives the signaling bit over a radio control channel (RCC) and performs periodic SRS (p-SRS).   The UE receives the signaling bit included in downlink control information (DCI) through a physical downlink control channel (PDCCH) and triggers aperiodic SRS (ap-SRS). The method according to claim 15.

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