WO2012167589A1 - Method and system for sending srs - Google Patents

Abstract

Disclosed are a method and system for sending a sounding reference signal (SRS). The method includes: user equipment (UE) sending an SRS to a base station on a time domain resource, frequency domain resource and/or code domain resource; wherein the time domain resource includes: the last time domain symbol, the first time domain symbol or the second last time domain symbol of a subframe where an SRS period is located; the frequency domain resource includes: the frequency domain location or a sending frequency comb of the SRS; and the code domain resource is obtained by the following ways: the UE generating a sequence group number of the SRS according to a user specific parameter configured for the UE by the base station by way of high-layer signalling, and determining the code domain resource required for sending the SRS according to the generated sequence group number of the SRS. The present invention can increase the available resources of the SRS, improve the user multiplexing capacity of the SRS, and enhance the channel estimation quality of the SRS by a base station, thus supporting the application of the coordinated multi-point transmission and reception (CoMP) system more effectively.

Description

 Method and system for transmitting SRS

 The present invention relates to a high-speed LTE (LTE-A) measurement reference signal (SRS) related technology, and more particularly to a SRS transmission method and system. Background technique

The uplink physical channel of the Long Term Evolution (LTE) system includes a Physical Random Access Channel (PRACH), a Physical Uplink Shared Channel (PUSCH), and a Physical Uplink Control Channel (PUCCH, Physical). Uplink Control Channel ) ₀ where PUSCH has two different cyclic prefixes (CP, Cyclic Prefix) lengths, which are Normal Cyclic Prefix and Extended Cyclic Prefix o PUSCH Each sub-frame (Subframe) consists of two slots (Slots). For different cyclic prefix lengths, the Demodulation Reference Signal (DMRS) will be in different positions in the sub-frame. As shown in FIG. 1a and FIG. 1b, FIG. 1a and FIG. 1b are schematic diagrams of time domain locations of the DMRS in the prior art, where FIG. 1a is a time domain location diagram of the DMRS when a normal cyclic prefix is used, and each subframe contains 14 Orthogonal Frequency Division Multiplexing (OFDM) symbols, including DMRS symbols, OFDM symbols represent the time domain position of one subframe; FIG. 1b is a schematic diagram of the time domain position of the DMRS when the cyclic prefix is extended, each sub- The frame contains 12 time domain data OFDM symbols.

 CoMP, Coordinated Multi-Point Transmission and

Reception ) is to use the transmit antennas of multiple cells (Cell) to achieve high-capacity and reliable transmission of the wireless link at the cell edge, which can effectively solve the problem of cell edge interference. The basic principle of multipoint transmission and the structure diagram of multi-cell joint processing are shown in Figure 2. Down CoMP divided into two categories: Joint Processing / transmission joint (JP / JT, Joint Processing / Joint Transmission) and coordinated scheduling / beamforming (CS / CB, Coordinated Scheduling / Beamforming) 0 in the JT, data from multiple cells simultaneously Transmit, and transmit data, scheduling, and channel state information only interact between multiple transmission points in the collaboration set; whereas in CS/CB, only the serving cell sends data to the user terminal (UE), scheduling and Beamforming information in CoMP Collaboration focuses on interaction. Different cells participating in the transmission or cooperation form a cooperation set. For a user terminal (UE, User Equipment), one cell in the cooperation set is a serving cell, and the remaining cells are coordinated cells.

 The Sounding Reference Signal (SRS) is a signal used by the UE and the base station to measure the Channel State Information (CSI). In the LTE system, the UE sends an uplink SRS on the last data symbol of the transmitting subframe according to parameters such as bandwidth, frequency domain location, sequence cyclic shift, period, and subframe offset indicated by the base station (eNB, Evolved NodeB); The eNB determines the uplink CSI of the UE according to the received SRS, and performs operations such as frequency domain selection scheduling, closed loop power control, and the like according to the obtained CSI.

In the LTE system, the SRS sequence sent by the UE is obtained by cyclically shifting a root sequence _v («) in the time domain. By performing different cyclic shifts on the same root sequence, different SRS sequences can be obtained, and the obtained SRS sequences are orthogonal to each other. Therefore, these SRS sequences can be allocated to different UEs to implement inter-UE communication. Code division multiple access. In the LTE system, the SRS sequence defines eight cyclic shifts, given by equation (1):

n ^cs

 α = 2π^^ ( 1 )

 8

In formula (1), 11^ is indicated by 3-bit signaling, which are 0, 1, 2, 3, 4, 5, 6, and 7, respectively. That is to say, in the same time-frequency resource, the UE in the cell has 8 available code resources, and the eNB can configure up to 8 UEs to simultaneously send the SRS on the same time-frequency resource. Equation (1) can be regarded as dividing the SRS sequence into 8 parts at equal intervals in the time domain, but since the length of the SRS sequence is a multiple of 12, the minimum length of the SRS sequence is 24. In the LTE system, the frequency domain bandwidth of the SRS is configured in a tree structure. Each SRS bandwidth configuration corresponds to a tree structure. The SRS bandwidth of the highest layer (or the first layer) (SRS-Bandwidth) corresponds to the maximum SRS bandwidth of the SRS bandwidth configuration, or SRS bandwidth. range. The UE calculates its own SRS bandwidth according to the signaling indication of the base station, and then determines the initial frequency domain position of the SRS by itself according to the upper layer signaling frequency domain location transmitted by the eNB. FIG. 3 is a schematic diagram of a frequency domain initial position in which a different UE is allocated to transmit SRS in the prior art. As shown in FIG. 3, UEs allocated with different 3⁄4^ will transmit SRS in different areas of a cell SRS bandwidth, where UE1 Determining the frequency initial position of the transmitting SRS according to 3⁄4^ =0, UE2 determines the frequency initial position of the transmitting SRS according to 3⁄4^=3, UE3 determines the frequency initial position of transmitting the SRS according to 3⁄4^=4, and UE4 determines to send the SRS according to 3⁄4^=6 The initial position of the frequency.

 The sequence used by the SRS is selected from the demodulation pilot sequence group. When the SRS bandwidth of the UE is 4 resource blocks (RB, Resource Block), the computer generated (CG, Computer Generated) with a length of 2 RBs is used. Sequence; When the SRS bandwidth of the UE is greater than 4 RBs, a corresponding length of Zadoff-Chu (ZC) sequence is used.

 In addition, within the same SRS bandwidth, the sub-carriers of the SRS are placed at intervals, that is, the SRS is transmitted in a comb structure. The number of frequency combs in the LTE system is 2, which also corresponds to a time domain repeat coefficient value (RPF, RePetition Factor) of 2. Fig. 4 is a schematic view showing the comb structure of the prior art SRS. In Fig. 4, the small square of the dot filling indicates the case of Comb = 1, and the small square filled with the diamond lattice indicates the case of Comb = 0. As shown in Figure 4, each UE uses only one of the two frequency combs when transmitting the SRS, Comb=0 or Comb=l. In this way, the UE transmits the SRS using only the subcarriers whose frequency domain index is even or odd according to the frequency comb comb position indication of the 1-bit upper layer signaling. This comb structure allows more UEs to send SRS within the same SRS bandwidth.

Within the same SRS bandwidth, multiple UEs can use different cyclic shifts on the same frequency comb, and then send SRS through code division multiplexing, or two UEs can comb on different frequencies. The SRS is transmitted over frequency division multiplexing. For example, in an LTE system, a UE that transmits an SRS within a certain SRS bandwidth (4 RBs) can use 8 cyclic shifts and 2 frequency combs that can be used, so the UE has a total of 16 Resources that can be used to send SRS, that is, up to 16 SRSs can be sent simultaneously within this SRS bandwidth. Since the uplink single-user multiple input multiple output (SU-MIMO) is not supported in the LTE system, the UE can only transmit one SRS at each time, so only one SRS resource is needed for one UE. Within the above SRS bandwidth, the system can multiplex up to 16 UEs at the same time.

 The advanced LTE (LTE-A, LTE-Advanced) system is a next-generation evolution system of the LTE system, supports SU-MIMO in the uplink, and can use up to four antennas as uplink transmitting antennas. That is, the UE can simultaneously transmit SRS on multiple antennas at the same time, and the eNB needs to estimate the state on each channel according to the SRS received on each antenna.

In the existing research of LTE-A Release 10 (LTE-A Release 10), it is proposed that in uplink communication, non-precoding (ie, antenna-specific) SRS should be used, and DMRS of PUSCH should be pre-coded. The base station can estimate the original CSI of the uplink by receiving the non-precoded SRS, and the pre-coded DMRS cannot enable the base station to estimate the original CSI of the uplink. At this time, when the UE transmits the non-precoded SRS by using multiple antennas, the SRS resources required by each UE are increased, which causes the number of UEs that can be simultaneously multiplexed in the system to decrease. The UE may send the SRS by using the high-level signaling (also referred to as triggered by the trigger type 0) or the downlink control information (also referred to as triggering by the trigger type 1). The high-level signaling is triggered by the periodic SRS, based on the downlink. The control information triggers a non-periodic SRS. Although the method of aperiodic transmission of SRS is added in LTE-ARelease 10, the utilization of SRS resources is improved to some extent, and the flexibility of resource scheduling is improved, but in the future research of LTE-ARelease 11 (LTE-A version 11) In order to reduce the feedback amount of the UE, the CoMP system often uses the channel reciprocity to obtain the downlink CSI by measuring the SRS; in addition, the application of the distributed RRHs with the same cell ID with the same cell ID The number of users in the cell increases, so it is on the SRS The user reuse capacity puts forward higher requirements. How to further increase the available resources of SRS, improve the user multiplexing capacity of SRS, improve the channel estimation quality of the SRS by the receiving end (base station), and more effectively support the application of the CoMP system is an urgent problem to be solved. Summary of the invention

 In view of this, the main purpose of the present invention is to provide a method and system for transmitting SRS, so as to increase the available resources of the SRS, improve the user multiplexing capacity of the SRS, and improve the channel estimation quality of the SRS by the base station.

 In order to achieve the above object, the technical solution of the present invention is achieved as follows:

 The present invention provides a method for transmitting a measurement reference signal (SRS), the method comprising: a user terminal (UE) transmitting an SRS to a base station on a time domain resource, a frequency domain resource, and/or a code domain resource; The domain resource includes: a last time domain symbol of the subframe in which the SRS period is located, or a first time domain symbol, or a second to last time domain symbol; the frequency domain resource includes: a frequency domain location of the SRS or a transmission frequency of the SRS The code domain resource is obtained by: the UE generates a sequence group number of the SRS according to a user-specific parameter configured by the base station for the UE through the high layer signaling, and determines to send the SRS according to the sequence group number of the generated SRS. The required code domain resource.

 The sequence group number of the SRS is: a sequence group number used for a physical uplink control channel (PUCCH), or a sequence group number of a demodulation reference signal (DMRS) for a physical uplink shared channel (PUSCH).

 The sequence group number for the PUCCH is obtained by:

" = (/ " _s ) + / _ss ^PUCCH ) mod 30

Wherein M denotes a sequence group number for PUCCH, / _gh (« _s ) denotes a group jump pattern, /J ^UCCH denotes a sequence shift pattern of PUCCH, and mod denotes an ear 4 运算 operation.

The / ^υ∞Η is derived by:

30 + A_ss n_Od 30 或 /J^UCCH = (N^ mod 30 + Δ )mod 30 其中， N^表示物理层小区标识（ID), A_ss是高层信令为 PUSCH配置 的偏置参数， A_sse{0,l,...,29}; Δ 是高层信令为 SRS 配置的偏置参数， Δ {0,1,···,29}。 所述 /_ss ^PUCCH通过以下方式得出： Sr ^CH =

30 + A _ss n _O d 30 Or /J ^UCCH = (N^ mod 30 + Δ ) mod 30 where N^ represents the physical layer cell identifier (ID), and A _ss is the offset parameter of the high layer signaling configured for the PUSCH, A _ss e{0,l, ..., 29}; Δ is the offset parameter configured by the higher layer signaling for SRS, Δ {0,1,···, 29}. The / _ss ^PUCCH is derived as follows:

/ ^CH =fc. c(8" _s +0'2')m _O d30 where represents a pseudo-random sequence, _s denotes the slot number within a radio frame, and c _init = "RNTI for pseudo-random at the beginning of each radio frame Sequence generator initialization, n RNTI

 30 is the temporary identifier of the wireless network, and ^^^ is the user-specific number configured by the base station for the UE through high layer signaling.

The _ (n ) is obtained by:

If the group jump is not enabled, the value of / ^ o is 0; if the group jump is enabled, the value of / ^Ο is (∑: ₌ .c(8« _s + ).2 mod30, where , represents a pseudo-random sequence, and " _s " denotes the slot number within a radio frame.

 Before the sending of the SRS to the base station by the UE on the frequency domain resource, the method further includes: configuring, by the base station, the SRS resource occupation information sent by the coordinated cell through the X2 interface, and configuring the UE of the cell to which the base station belongs The SRS resources of the coordinated cell do not overlap.

The SRS is transmitted on the SRS frequency domain location or frequency comb.

 Before the sending of the SRS to the base station by the UE on the frequency domain resource, the method further includes: sending, by the base station, the SRS resource occupation information of the local cell to the coordinated cell by using the X2 interface. The method further includes:

The physical resource block (PRB) occupation indication of the SRS through the information element (IE) item of the X2 interface, And/or user-specific parameter information of the SRS of the IE item, to represent the resource occupation information of the SRS.

 The PRB occupation indication of the IE item SRS includes: a CoMP SRS indication per PRB; the user-specific parameter information of the IE item SRS includes: a user-specific CoMP SRS information indication.

 The number of transmission frequency combs of the SRS is 2, 3 or 4.

 The present invention further provides a SRS transmission system, the system includes: a UE and a base station, where the UE is configured to send an SRS to a base station on a time domain resource, a frequency domain resource, and/or a code domain resource; The time domain resource includes: a last time domain symbol of a subframe in which the SRS period is located, or a first time domain symbol, or a second to last time domain symbol; the frequency domain resource includes: a frequency domain location of the SRS or an SRS The transmission frequency comb is obtained by: the UE generates a sequence group number of the SRS according to a user-specific parameter configured by the base station for the UE by using the high layer signaling, and determines the sequence group number of the SRS according to the sequence number of the generated SRS. The code domain resource required to send the SRS;

 The base station is configured to receive, by using a time domain resource, a frequency domain resource, and/or a code domain resource, an SRS sent by the UE.

 The sequence group number of the SRS is: a sequence group number for PUCCH or a sequence group number for DMRS for PUSCH.

 The sequence group number for the PUCCH is obtained by:

" = (/ " _s ) + / _ss ^PUCCH ) mod 30

Wherein M denotes a sequence group number for PUCCH, / _gh (« _s ) denotes a group jump pattern, /J ^UCCH denotes a sequence shift pattern of PUCCH, and mod denotes an ear 4 运算 operation.

The /J ^UCCH is obtained by: or / _ss ^PUCCH = (N^ mod 30 + Δ: ) mod 30

Where Λ^ ¹¹ represents the physical layer cell identifier (ID), A _ss is the offset parameter configured by the high layer signaling for the PUSCH, A _ss e {0, l,..., 29}; Δ is the high layer signaling for the SRS Configured offset parameters, Δ {0,1,···, 29}. The / _ss ^PU∞H is obtained by:

/ ^CH =(∑:=.c(8" _s +0'2')m _O d30 where represents a pseudo-random sequence, " _s represents the slot number within a radio frame, used at the beginning of each radio frame "RNTI

c _init = initialize the pseudo-random sequence generator, n

 30 is the temporary identifier of the wireless network, "^^ is the user-specific parameter configured by the base station for the UE through high layer signaling.

 The _ (n ) is obtained by:

+ ).2^;)mod30 如果组跳转不使能， 则/ ^ o 的取值为 0; 如果组跳转使能， 则/ 的取值为 (∑:₌。c(8«_s+ ).2 mod30, 其中， 表示伪随机序列， 《_s表示一 个无线帧内的时隙编号。 ,»

+ ).2 ^; )mod30 If the group jump is not enabled, the value of / ^ o is 0; if the group jump is enabled, the value of / is (∑: ₌ ..c(8« _s + ) .2 mod30, where represents a pseudo-random sequence, " _s " denotes the slot number within a radio frame.

 The base station is further configured to: before the UE sends the SRS to the base station on the frequency domain resource, configure the UE in the cell to which the base station belongs according to the received SRS resource occupation information sent by the coordinated cell through the X2 interface. The SRS of the cell does not overlap with the SRS frequency domain location or frequency comb to send the SRS.

 The base station is further configured to send the SRS resource occupation information of the local cell to the coordinated cell by using the X2 interface before the UE sends the SRS to the base station on the frequency domain resource.

 The resource occupancy information of the SRS is indicated by the information element (IE) of the X2 interface, the physical resource block (PRB) occupation indication of the SRS, and/or the user-specific parameter information of the SRS of the IE item.

 The PRB occupation indication of the IE item SRS includes: a CoMP SRS indication per PRB; the user-specific parameter information of the IE item SRS includes: a user-specific CoMPSRS information indication.

 The number of transmission frequency combs of the SRS is 2, 3 or 4.

A method and system for transmitting SRS provided by the present invention, by UE in time domain resources and frequency The SRS is sent to the base station on the domain resource and/or the code domain resource, where the time domain resource includes: a last time domain symbol of the subframe in which the SRS period is located, or a first time domain symbol, or a second to last time domain symbol; The frequency domain resource includes: a frequency domain location of the SRS or a transmission frequency comb of the SRS; the code domain resource is obtained by: the UE generates a sequence group number of the SRS according to a user-specific parameter configured by the base station by using the high layer signaling for the UE, and The code domain resource required to transmit the SRS is determined according to the sequence group number of the generated SRS. Through the invention, the available resources of the SRS can be increased, the user multiplexing capacity of the SRS can be improved, the channel estimation quality of the SRS by the base station can be improved, and the application of the CoMP system can be more effectively supported. DRAWINGS

 FIG. 1 is a schematic diagram of a time domain location of a DMRS when a normal cyclic prefix is used in the prior art; FIG. 1b is a schematic diagram of a time domain location of a DMRS when an extended cyclic prefix is used in the prior art; FIG. 2 is a basic diagram of multipoint transmission in the prior art. Schematic diagram of the principle and multi-cell joint processing;

3 is a schematic diagram of a frequency domain initial position in which different _RRC UEs transmit SRSs in the prior art;

 4 is a schematic view of a comb structure of an SRS in the prior art;

 FIG. 5 is a flowchart of a method for sending an SRS according to an embodiment of the present invention. detailed description

 The technical solutions of the present invention are further elaborated below in conjunction with the accompanying drawings and specific embodiments. The method for sending the SRS provided by the embodiment of the present invention, as shown in FIG. 5, includes:

The UE sends an SRS to the base station on the time domain resource, the frequency domain resource, and/or the code domain resource. The time domain resource includes: a last time domain symbol of the subframe in which the SRS period is located, or a first time domain symbol, or a reciprocal The second time domain symbol; the frequency domain resource includes: a frequency domain location of the SRS or a transmission frequency comb of the SRS; the code domain resource is obtained by: the UE configuring the UE according to the high layer signaling by the base station The user-specific parameter generates a sequence group number (SRS sequence-group number) of the SRS, and determines a code domain resource required for transmitting the SRS according to the sequence group number of the generated SRS.

 Here, the sequence group number for the PUCCH may be used as the sequence group number of the SRS; or the sequence group number of the DMRS for the PUSCH may be used as the sequence group number of the SRS.

 By setting the UE to send the SRS to the base station in the last time domain symbol of the subframe in which the SRS period is located, or the first time domain symbol, or the second last time domain symbol, the available resources of the SRS can be increased, and the user of the SRS is improved. Use capacity.

 The method for transmitting the SRS in the embodiment of the present invention will be described in detail below with reference to specific embodiments.

 In the first embodiment of the present invention, the UE sends an SRS to the base station on the code domain resource. The code domain resource is obtained by: the UE generates a sequence group number of the SRS according to a user-specific parameter configured by the base station for the UE by using high layer signaling (such as radio resource control RRC signaling), and according to the generated SRS The sequence group number determines the code domain resources required to send the SRS.

 Here, the sequence group number for the PUCCH may be used as the sequence group number of the SRS; or the sequence group number of the DMRS for the PUSCH may be used as the sequence group number of the SRS.

When the sequence group number for PUCCH is used as the sequence group number of the SRS, it is necessary to determine the sequence-shift pattern / _s ^{UCCH of the} PUCCH by one of the following two methods.

Method 1: Pass the following formula (2) or (3) « : ^UCCH :

/ _ss ^PUCCH = (A mod 30 + A _ss ) mod 30 ( 2 ) s _s ^PUCCH = (A mod 30 + Δ: ) mod 30 ( 3 ) where Λ ¹¹ represents the physical layer cell identity (ID), A _ss It is the offset parameter (groupAssignmentPUSCH ) configured by the high layer signaling for the PUSCH, A _ss e {0,1,...,29}; Δ is the offset parameter (groupAssignmentSRS ) configured by the upper layer signaling for the SRS, Δ e {θ ,1,···,29}. ^ is the user-specific parameter configured by the base station for the UE through high-level signaling, if used The formula (2) obtains / _ss ^pueeH , then the user-specific parameter refers to A _ss ; if the above formula (3 ) is used to obtain / _ss ^PUCCH , then the user-specific parameter refers to Δ . Method 2: Obtain ^UCCH by the following formula (4):

Where is the pseudo random sequence J ¹ J ( seudo-random sequence ) , « _s is a slot number within a radio frame, using ^C init for pseudo-random at the beginning of each radio frame The sequence generator is initialized, " _RNTT is the wireless network temporary identifier

 30

(Radio Network Temporary Identifier), η^ _{τι is} the user-specific parameter configured by the foregoing base station for the UE through high layer signaling.

After obtaining / _SS ^PU∞H , the sequence group number M for PUCCH is obtained by the following formula (5): " = (/ _g "" _s ) + / _ss ^PUCCH ) mod 30 ( 5 ) where , ) is a group hop The group-hopping pattern is obtained by the following formula (6):

 0 if group hopping is disabled ( ^ )

( 8) , ^gh ( ^Ws ) | (∑. c(8« _s + i) · ) mod30 if group hopping is enabled That is, if the group jump is not enabled, the value of y^o is 0; if the group jump is enabled Then, the value of _ (« _s ) is (∑: _=D c(8« _s + · 2 ^! ) mod30. After obtaining the sequence group number M of the SRS, the UE obtains according to the following formula (7) ~ (10). The sequence r )(«) of the SRS is the code domain resource required to send the SRS:

( 8)

8p

""SRS " nSRS + ¹ mod 8 (9) _e fei ..,N _ap — 1} do) where " ={0,1,2,3, 4,5,6,7} is configured by higher layer signaling, which is the antenna port number for transmitting the SRS, Λ Number of antennas transmitting SRS The definition of the reference signal ^)(«) is consistent with the definition in the LTE protocol.

 When the sequence group number of the DMRS for PUSCH is used as the sequence group number of the SRS, the sequence-shift pattern of the PUSCH is obtained by the equations (11) and (12).

^ PUSCH

J ss.

f Touch _d 30 ( 11 ) s _s ^PUSCH = (/ _ss ^PUCCH + A _s ) mod30 ( 12 ) where A _ss is the user-specific offset parameter configured by the higher layer signaling for PUSCH

( groupAssignmentPUSCH ), A _ss e {θ,1,···, 29}.

After obtaining / _SS ^PUSCT , the sequence group number _M for the PUSCH is obtained by the following formula (13): " = (/» / _s ^USCH ) mod 30 ( 13) where f _gh (« _s ) is a group jump pattern (group-hopping pattern ) , obtained by the above formula (6).

After obtaining the sequence group number of the SRS, the UE obtains the sequence r _s ( _R «) of the SRS according to the foregoing formulas (7) to (10), that is, the code domain resources required for transmitting the SRS.

 In the above embodiment, the user-specific offset is configured for the UE, and the sequence group number for the PUCCH or the PUSCH is obtained based on the configured offset, as the sequence group number of the SRS, and the sequence group number of the UE in the SRS. The SRS is sent to the base station; thereby, the available resources of the SRS can be increased, and the user multiplexing capacity of the SRS is improved.

 In the second embodiment of the present invention, the UE sends an SRS to the base station on the frequency domain resource. The frequency domain resources include: a frequency domain location of the SRS or a transmission frequency comb of the SRS.

Further, before the UE sends the SRS to the base station, the base station is small according to the received cooperation. The SRS resource occupation information sent by the X2 interface is configured, and the UE of the local cell is configured to send the SRS on the SRS frequency domain location or frequency comb that does not overlap with the SRS resource of the coordinated cell. Avoiding transmitting SRS on the overlapping SRS frequency domain position or frequency comb can improve the channel estimation quality of the SRS by the receiving end (base station).

 Further, before the UE sends the SRS to the base station, the base station sends the SRS resource occupation information of the current cell to the coordinated cell by using the X2 interface.

 Further, the resource occupancy information of the SRS may be represented by an IE (Information Element) item of the X2 interface, a Physical Resource Block (PRB) occupation indication parameter, and/or a user-specific parameter information of the SRS. .

 Further, the physical resource block occupation information of the IE item SRS and the user-specific parameter information of the IE item SRS are IE items set on the LOAD INFORMATION message.

 Further, the PRB occupation indication of the IE item SRS includes: a CoMP SRS in PRB Indication per PRB; the user-specific parameter information of the IE item SRS includes: a user-specific CoMP SRS information indication (CoMP SRS ue- Specific Information Indication ).

For the IE term CoMP SRS in PRB Indication, it is assumed that the corresponding 4 bits on the i-th PRB (i </<iio) is b AA. . If =0000, there is no CoMP SRS on the i-th PRB; if =0001, it means that there is CoMP SRS on the i-th PRB, and comb==0 is occupied; if=0010, it means that there is CoMP SRS on the i-th PRB. And if comb = 1 is occupied; if =0100, it means that there is CoMP SRS on the i-th PRB, and comb=2 is occupied; if =1000, it means that there is CoMP SRS on the i-th PRB, and comb=3 is Occupancy; if =0011, it means that there is CoMP SRS on the i-th PRB, and comb=0 and comb=l are occupied; if =0101, it means that there is CoMP SRS on the i-th PRB, and comb=0 and comb= 2 is occupied; and so on, if b (j is 0 to 3) The integer corresponding to 1 indicates that there is CoMP SRS and comb=j is occupied.

 Further, the number of transmission frequency combs of the SRS can be configured as 2, 3 or 4. When the number of frequency combs is 2, each PRB corresponds to 2 bits. When the number of frequency combs is 3, each PRB corresponds to 3 bits; when the number of frequency combs is 4, each PRB corresponds to 4 bits.

 When the number of frequency combs is 4, the IE format newly added on the X2 interface is as shown in Table 1 below:

 Table 1

 For the IE item CoMP SRS ue-specific Information Indication, the UE-specific SRS parameter information sent by the ten-working cell through the X2 interface, that is, the information content of the interaction includes one or several UE-specific SRS parameters:

 SRS bandwidth ( srs-Bandwidth / srs-BandwidthAp ), set to: ENUMERATED {bwO, bwl, bw2, bw3};

The bandwidth of the frequency domain Hopping ( srs-HoppingBandwidth ) is set to: ENUMERATED {hbwO , hbwl , hbw2 , hbw3 }; The starting position of the allocated physical resource block

( freqDomainPosition/freqDomainPositionAp ), set to: NTEGER ( 0...23 );

 SRS transmission period (single or until not enabled) (duration), set to BOOLEAN;

The SRS configuration index ( srs-Configlndex / srs - ConfiglndexAp ) represents the period and start subframes, set to INTEGER ( 0..1023 ) /INTEGER ( 0..32 );

 The transmitted comb structure ( transmissionComb/transmissionCombAp ) is set to INTEGER ( 0, 1 , 2, 3 );

 The cyclic shift amount of the sequence (cyclicShift/cyclicShiftAp) is set to ENUMERATED {csO, csl, cs2, cs3, cs4, cs5, cs6, cs7}.

 The number of SRS transmit antennas ( srs-AntennaPort/srs-AntennaPortAp ) is set to INTEGER ( 0, 1 , 2, 4 );

 The IE format is shown in Table 2 below:

IE/group name Required range IE format reference Functional description

 ( IE/Group ( Range ) ( IE type and reference ) ( Semantics

Name ) description )

CoMP SRS 1 to <Num

 Ue-specific of

 Information

 Indication List User>

ENUMERATED per user by it

(in the list where srs-Bandwidth/srs-Bandwidth is located

A , srs-HoppingBandwidth , position determination: column freqDomainPosition , the first in the table

CoMP SRS duration/ freqDomainPosition , the element corresponds to the user ue-specific durationAp,

 M 0, the second element

Information srs-Configlndex/ srs-Configlndex corresponds to user 1 , etc.

Indication Ap,

 Wait.

 transmissionComb/transmission

 CombA,

 srs-AntennaPort/ srs-AntennaPort

Ap, ... ) Table 2

 Corresponding to the foregoing SRS sending method, an embodiment of the present invention further provides an SRS sending system, including: a UE and a base station. The UE is configured to send an SRS to the base station on the time domain resource, the frequency domain resource, and/or the code domain resource, where the time domain resource includes: a last time domain symbol of the subframe in which the SRS period is located, or the first The time domain symbol, or the second to last time domain symbol; the frequency domain resource includes: a frequency domain location of the SRS or a transmission frequency comb of the SRS; the code domain resource is obtained by: the UE adopting the high layer signaling according to the base station The user-specific parameters configured for the UE, the sequence group number of the SRS is generated, and the code domain resources required for transmitting the SRS are determined according to the sequence group number of the generated SRS. The base station is configured to receive, by using the time domain resource, the frequency domain resource, and/or the code domain resource, the SRS sent by the UE.

 The sequence group number of the SRS may be: a sequence group number used for the PUCCH, or a sequence group number of the DMRS used for the PUSCH.

 Further, the sequence group number for the PUCCH can be obtained by:

" = (/ " _s ) + / _ss ^PUCCH ) mod 30

Wherein M denotes a sequence group number for PUCCH, / _gh (« _s ) denotes a group jump pattern, /J ^UCCH denotes a sequence shift pattern of PUCCH, and mod denotes an ear 4 运算 operation.

 /JUCCH can be derived in the following ways:

_Λ ; ^^(^u earn _{d 3G + Ass} ) earn _{d 30}

 Or f = (A mod 30 + )mod 30

A indicates the physical layer cell identifier (ID), A _ss is the offset parameter configured by the high layer signaling for the PUSCH, A _ss e{0, l,..., 29}; Δ is the high layer signaling configured for the SRS Offset parameters, Δ {0,1,···, 29}.

/JUCCH can also be obtained by:

/ ^Η = (∑ (8" ₈ + '·) '2') intestinal d30

Wherein, represents a pseudo-random sequence, " _s represents a slot number within a radio frame, in each n

The beginning of the radio frame is used *"RNTI

c _init = Initialize the pseudo-random sequence generator, n RNTI

 30 is a wireless network temporary identifier, which is a user-specific number configured by the base station for the UE through high layer signaling.

4 (n _s ) can be derived as follows:

If the group jump is not enabled, the value of ) is 0; if the group jump is enabled, the value of K« _s :) is (∑: ₌ .c(8« _s + ) . 2 mod30 , where , represents a pseudo-random sequence, and n _s represents the slot number within a radio frame.

 Preferably, the base station is further configured to configure the UE in the cell to which the base station belongs according to the received SRS resource occupation information sent by the coordinated cell through the X2 interface before the UE sends the SRS to the base station on the frequency domain resource. The SRS of the cell does not overlap with the SRS frequency domain location or frequency comb to send the SRS.

 Preferably, the base station is further configured to: before the UE sends the SRS to the base station on the frequency domain resource, the base station sends the SRS resource occupation information of the local cell to the coordinated cell by using the X2 interface.

 The resource occupancy information of the SRS is represented by the physical resource block (PRB) occupation indication of the SRS of the X2 interface, and the user-specific parameter information of the SRS of the IE item. The PRB occupation indication of the IE item SRS includes: CoMP SRS in PRB Indication; the user-specific parameter information of the IE item SRS includes: CoMP SRS ue-specific Information Indication

 Preferably, the physical resource block occupation information of the IE item SRS and the user-specific parameter information of the IE item SRS are IE items set on the LOAD INFORMATION message.

 The above description is only a preferred embodiment of the present invention, and is not intended to limit the protection of the present invention.

Claims

Claim A method for transmitting a measurement reference signal (SRS), the method comprising: transmitting, by a user terminal (UE), a base station resource, a frequency domain resource, and/or a code domain resource to a base station The time domain resource includes: a last time domain symbol of the subframe in which the SRS period is located, or a first time domain symbol, or a second last time domain symbol; the frequency domain resource includes: a frequency of the SRS The field location or the transmission frequency comb of the SRS; the code domain resource is obtained by: the UE generating the sequence group number of the SRS according to the user-specific parameters configured by the base station for the UE through the high layer signaling, and according to the generated SRS The sequence group number determines the code domain resources required to send the SRS.  The method for transmitting an SRS according to claim 1, wherein the sequence group number of the SRS is: a sequence group number used for a physical uplink control channel (PUCCH), or used for a physical uplink shared channel (PUSCH). The sequence group number of the demodulation reference signal (DMRS).  The method for transmitting an SRS according to claim 2, wherein the sequence group number for the PUCCH is obtained by: " = (/ " _s ) + / _ss ^PUCCH ) mod 30 Wherein M denotes a sequence group number for PUCCH, / _gh (« _s ) denotes a group jump pattern, /J ^UCCH denotes a sequence shift pattern of PUCCH, and mod denotes an ear 4 运算 operation.  4. The method for transmitting an SRS according to claim 3, wherein the method is as follows: : _U CCH _{= ( l mod 30 + A} J _mod 30 Or / _ss ^PUCCH = (A mod 30 + )mod 30 Where Λ^ ¹¹ represents the physical layer cell identifier (ID), A _ss is the offset parameter configured by the high layer signaling for the PUSCH, A _ss e{0, l,..., 29}; Δ is the high layer signaling for the SRS Configured offset parameters, Δ {0,1,···, 29}. The method for transmitting an SRS according to claim 3, wherein the / _ss ^pueeH pass The following way is obtained:

Wherein, represents a pseudo-random sequence, " _s represents a slot number within a radio frame, and uses a c _init = *" RNTI to initialize the pseudo-random sequence generator at the beginning of each radio frame, ", for the wireless network temporary identifier The dish is a user-specific parameter configured by the base station for the UE through high layer signaling. The method for transmitting an SRS according to claim 3, wherein the _ 0 is obtained by:

If the group jump is not enabled, the value of ) is 0; if the group jump is enabled, the value of K« _s :) is (∑: ₌ .c(8« _s + ) . 2 mod30 , where , represents a pseudo-random sequence, and n _s represents the slot number within a radio frame.  The method for transmitting an SRS according to claim 1, wherein before the sending, by the UE, the SRS to the base station on the frequency domain resource, the method further includes:  The base station configures the UE of the cell to which the base station belongs to transmit the SRS on the SRS frequency domain position or the frequency comb that does not overlap with the SRS resource of the coordinated cell, according to the received SRS resource occupation information sent by the coordinated cell through the X2 interface.  The method for transmitting an SRS according to claim 1, wherein before the sending, by the UE, the SRS to the base station on the frequency domain resource, the method further includes:  The base station sends the SRS resource occupation information of the local cell to the coordinated cell by using the X2 interface.  The method for transmitting an SRS according to claim 7 or 8, wherein the method further comprises: The information element (IE) of the X2 interface, the physical resource block (PRB) occupation indication of the SRS, And/or user-specific parameter information of the SRS of the IE item, to represent the resource occupation information of the SRS.  The method for transmitting the SRS according to claim 9, wherein the PRB occupation indication of the IE item SRS includes: a CoMP SRS indication per PRB; the user-specific parameter information of the IE item SRS includes: Some CoMP SRS information is indicated.  The method for transmitting an SRS according to any one of claims 1 to 8, characterized in that the number of transmission frequency combs of the SRS is 2, 3 or 4.  12. A SRS transmission system, the system comprising: a UE and a base station, wherein  The UE is configured to send an SRS to the base station on the time domain resource, the frequency domain resource, and/or the code domain resource, where the time domain resource includes: a last time domain symbol of the subframe in which the SRS cycle is located, or the first The time domain symbol, or the second to last time domain symbol; the frequency domain resource includes: a frequency domain location of the SRS or a transmission frequency comb of the SRS; the code domain resource is obtained by: the UE adopting high layer signaling according to the base station a user-specific parameter configured for the UE, generating a sequence group number of the SRS, and determining a code domain resource required for transmitting the SRS according to the sequence group number of the generated SRS;  The base station is configured to receive, by using a time domain resource, a frequency domain resource, and/or a code domain resource, an SRS sent by the UE.  The SRS transmission system according to claim 12, wherein the sequence group number of the SRS is: a sequence group number used for the PUCCH, or a sequence group number of the DMRS for the PUSCH.  14. The SRS transmission system according to claim 13, wherein the sequence group number for the PUCCH is obtained by: " = (/ " _s ) + / _ss ^PUCCH ) mod 30 Wherein M denotes a sequence group number for PUCCH, / _gh (« _s ) denotes a group jump pattern, /J ^UCCH denotes a sequence shift pattern of PUCCH, and mod denotes an ear 4 运算 operation. A transmission system for an SRS according to claim 14, wherein said The following way is obtained: _Λ; ^^ (^ u earned _{d 3G + Ass) d 30} or make ^{_{/ ss PUCCH = (A mod 30}} +) mod 30 where, A denotes a physical layer cell identification (ID), A _ss PUSCH layer signaling is arranged The offset parameter, A _ss e{0,l,...,29}; Δ is the offset parameter configured by the high-level signaling for SRS, Δ {0,1,···, 29}. 16. The SRS transmission system according to claim 14, wherein the / _ss ^PueeH is obtained by:

Wherein, represents a pseudo-random sequence, " _s represents a slot number within a radio frame, at each n The initial stage of the radio frame initializes the pseudo-random sequence generator with c _init = *"RNTI, n R TI  30 is a wireless network temporary identifier, which is a user-specific number configured by the base station for the UE through high layer signaling. 17. The SRS transmission system according to claim 14, wherein said _ < is obtained by:

If the group jump is not enabled, the value of ) is 0; if the group jump is enabled, the value of K« _s :) is (∑^^(8^+ ).2 ^; ')1110(130 , where represents a pseudo-random sequence, " _s represents the slot number within a radio frame. The SRS transmitting system according to claim 12, wherein the base station is further configured to send, according to the received coordinated cell, an X2 interface, before the UE sends an SRS to a base station on a frequency domain resource. The SRS resource occupation information of the incoming cell is configured, and the UE of the cell to which the base station belongs is configured to transmit the SRS frequency domain position or frequency comb that does not overlap with the SRS resource of the coordinated cell. Send SRS.  The SRS transmission system according to claim 12, wherein the base station is further configured to: before the UE sends an SRS to the base station on the frequency domain resource, send the SRS of the local cell to the coordinated cell by using the X2 interface. Resource occupancy information.  20. The SRS transmission system according to claim 18 or 19, characterized in that The information element (IE) of the X2 interface, the physical resource block (PRB) of the SRS, and/or the user-specific parameter information of the IE item SRS, represent the resource occupation information of the SRS.  The SRS transmission system according to claim 20, wherein the PRB occupation indication of the IE item SRS includes: a CoMP SRS indication per PRB; the user-specific parameter information of the IE item SRS includes: Some CoMP SRS information is indicated.  The transmission system of the SRS according to any one of claims 12 to 19, characterized in that the number of transmission frequency combs of the SRS is 2, 3 or 4.