METHOD AND DEVICE FOR 3D MIMO COMMUNICATION IN UE AND BASE STATION

Abstract

The present disclosure provides a method and device for 3D MIMO communication in a UE and a base station. In an embodiment, in a first step, a UE receives a downlink reference signal in a first RS resource and a second RS resource; in a second step, the UE determines a target RS resource, wherein the target RS resource is the first RS resource or the second RS resource; and in a third step, the UE feeds back a first CI and a first index, wherein the first RS resource comprises N1 RS ports, the second RS resource comprises N2 RS ports, a reference RS of the first CI is the target RS resource, the first index indicates the target RS resource, N1 is a positive integer greater than 1, and N2 is a positive integer greater than 1. By using the technical scheme provided in the present invention, a UE feeds back the most effective CI information by using limited air-interface resources, and therefore overheads of the air-interface resources are reduced or the feedback efficiency of the CI is improved.

Claims

1. A method for 3D MIMO communication in a UE, comprising the following steps: Step A: receiving a downlink reference signal in a first RS resource and a second RS resource; Step B: determining a target RS resource, wherein the target RS resource is the first RS resource or the second RS resource; Step C: feeding back a first CI and a first index; wherein the first RS resource comprises N1 RS ports, the second RS resource comprises N2 RS ports, a reference RS of the first CI is the target RS resource, the first index indicates the target RS resource, N1 is a positive integer greater than 1, and N2 is a positive integer greater than 1.

2. The method for 3D MIMO communication in the UE according to claim 1, wherein the Step C comprises the following step: Step C0: feeding back a first CQI; wherein the first CQI is determined under a condition that the UE assumes that a PMI value corresponding to the CI in a reported CI set is adopted by a base station, and a reference RS of the first CQI comprises the first RS resource and the second RS resource; the reported CI set comprises the first CI and a second CI; the second CI is a latest CI fed back by the UE, the reference RS of which is a RS resource in {the first RS resource, the second RS resource} and other than the target RS resource.

3. The method for 3D MIMO communication in the UE according to claim 1, wherein the Step A comprises the following step: Step A1: receiving an uplink scheduling DCI, wherein the uplink scheduling DCI comprises a CSI scheduling bit; the Step C further comprises the following step: Step C1: transmitting an A-CSI on a PUSCH; wherein the CSI scheduling bit indicates one of the first RS resource and the second RS resource, a reference RS of the A-CSI is a RS resource indicated by the CSI scheduling bit; the A-CSI comprises at least one of {CI, CQI}.

4. The method for 3D MIMO communication in the UE according to claim 2, wherein the Step C further comprises the following step: Step C2: feeding back a third CI; wherein the reported CI set comprises the third CI, and the third CI is determined under a condition that the UE assumes that PMI values corresponding to the first CI and the second CI are adopted by the base station.

5. The method for 3D MIMO communication in the UE according to claim 1, wherein transmitting resources of the first CI and the second CI are orthogonal on a time domain; the first CI and the second CI occupy the same PUCCH resource in a sub frame; the second CI is a latest CI fed back by the UE, the reference RS of which is a RS resource in {the first RS resource, a second RS resource} and other than the target RS resource.

6. The method for 3D MIMO communication in the UE according to claim 1, wherein the first index is one bit, and the first index identifies that the target RS resource is the first RS resource or the second RS resource; or a pattern of the RS port inside a PRBP is a pattern of a CSI-RS port inside the PRBP.

7. The method for 3D MIMO communication in the UE according to claim 1, wherein the first CI and the first index are transmitted in the same PUCCH of the same sub frame.

8. A method for 3D MIMO communication in a base station, comprising the following steps: Step A: transmitting a downlink reference signal in a first RS resource and a second RS resource; Step B: receiving a first CI and a first index; Step C: determining a downlink channel parameter; wherein the first RS resource comprises N1 RS ports, the second RS resource comprises N2 RS ports, N1 is a positive integer greater than 1, and N2 is a positive integer greater than 1; a reference RS of the first CI is the target RS resource, the target RS resource is the first RS resource or the second RS resource, and the first index indicates the target RS resource.

9. The method for 3D MIMO communication in the base station according to claim 8, wherein the Step B comprises the following step: Step B0: receiving a first CQI; wherein the first CQI is determined under a condition that a transmitting UE assumes that a PMI value corresponding to the CI in a reported CI set is adopted by the base station, and a reference RS of the first CQI comprises the first RS resource and the second RS resource; the reported CI set comprises the first CI and a second CI; the second CI is a latest CI fed back by the transmitting UE, the reference RS of which is a RS resource in {the first RS resource, the second RS resource} and other than the target RS resource.

10. The method for 3D MIMO communication in the base station according to claim 8, wherein the Step A comprises the following step: Step A1: transmitting an uplink scheduling DCI, wherein the uplink scheduling DCI comprises a CSI scheduling bit; the Step B further comprises the following step: Step B1: receiving an A-CSI on a PUSCH; wherein the CSI scheduling bit indicates one of the first RS resource and the second RS resource, a reference RS of the A-CSI is a RS resource indicated by the CSI scheduling bit; the A-CSI comprises at least one of {CI, CQI}.

11. The method for 3D MIMO communication in the base station according to claim 9, wherein the Step B further comprises the following step: Step B 2: receiving a third CI; wherein the reported CI set comprises the third CI, and the third CI is determined under a condition that the UE assumes that PMI values corresponding to the first CI and the second CI are adopted by the base station.

12. The method for 3D MIMO communication in the base station according to claim 8, wherein transmitting resources of the first CI and the second CI are orthogonal on a time domain; the first CI and the second CI occupy the same PUCCH resource in a sub frame; the second CI is a latest CI fed back by the transmitting UE, the reference RS of which is a RS resource in {the first RS resource, a second RS resource} and other than the target RS resource.

13. The method for 3D MIMO communication in the base station according to claim 8, wherein the first index is one bit, and the first index identifies that the target RS resource is the first RS resource or the second RS resource; or a pattern of the RS port inside a PRBP is a pattern of a CSI-RS port inside the PRBP.

14. The method for 3D MIMO communication in the base station according to claim 8, wherein the first CI and the first index are transmitted in the same PUCCH of the same sub frame.

15. A user equipment, characterized in that, the UE comprises: a first module, for receiving a downlink reference signal in a first RS resource and a second RS resource; a second module, for determining a target RS resource, wherein the target RS resource is the first RS resource or the second RS resource; a third module, for feeding back a first CI and a first index; wherein the first RS resource comprises N1 RS ports, the second RS resource comprises N2 RS ports, a reference RS of the first CI is the target RS resource, the first index indicates the target RS resource, N1 is a positive integer greater than 1, and N2 is a positive integer greater than 1; transmitting resources of the first CI and the second CI are orthogonal on a time domain; the first CI and the second CI occupy the same PUCCH resource in a sub frame; the second CI is a latest CI fed back by the UE, the reference RS of which is a RS resource in {the first RS resource, a second RS resource} and other than the target RS resource.

16. The user equipment according to claim 15, wherein transmitting resources of the first CI and the second CI are orthogonal on a time domain: the first CI and the second CI occupy the same PUCCH resource in a sub frame: the second CI is a latest CI fed back by the UE, the reference RS of which is a RS resource in {the first RS resource, a second RS resource} and other than the target RS resource.

17. A base station equipment, characterized in that, the base station equipment comprises: a first module, for transmitting a downlink reference signal in a first RS resource and a second RS resource; a second module, for receiving a first CI and a first index; a third module, for determining a downlink channel parameter; wherein the first RS resource comprises N1 RS ports, the second RS resource comprises N2 RS ports, N1 is a positive integer greater than 1, and N2 is a positive integer greater than 1; a reference RS of the first CI is the target RS resource, the target RS resource is the first RS resource or the second RS resource, and the first index indicates the target RS resource; transmitting resources of the first CI and the second CI are orthogonal on a time domain; the first CI and the second CI occupy the same PUCCH resource in a sub frame; the second CI is a latest CI fed back by the transmitting UE, the reference RS of which is a RS resource in {the first RS resource, a second RS resource} and other than the target RS resource.

18. The base station according to claim 17, wherein transmitting resources of the first CI and the second CI are orthogonal on a time domain: the first CI and the second CI occupy the same PUCCH resource in a sub frame: The second CI is a latest CI fed back by the transmitting UE, the reference RS of which is a RS resource in {the first RS resource, a second RS resource} and other than the target RS resource.

19. The base station according to claim 18, wherein the first index is one bit, and the first index identifies that the target RS resource is the first RS resource or the second RS resource; or a pattern of the RS port inside a PRBP is a pattern of a CSI-RS port inside the PRBP; or the first CI and the first index are transmitted in the same PUCCH of the same sub frame.

20. The user equipment according to claim 15, wherein the first index is one bit, and the first index identifies that the target RS resource is the first RS resource or the second RS resource; or a pattern of the RS port inside a PRBP is a pattern of a CSI-RS port inside the PRBP; or the first CI and the first index are transmitted in the same PUCCH of the same sub frame.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0089] The above and other exemplary aspects, features and advantages of certain exemplary embodiments of the present invention will be more apparent from the following description taken in conjunction with the accompanying drawings, in which:

[0090] FIG. 1 is an example of a downlink RS pattern of the existing LTE system:

[0091] FIG. 2 is a flowchart of a CSI feedback according to one embodiment of the present invention;

[0092] FIG. 3 is a pattern of a first RS resource and a second RS resource inside PRBP according to one embodiment of the present invention;

[0093] FIG. 4 is a mapping diagram of a 4×4 cross polarized antenna array disposed on a base station side to a RS port according to one embodiment of the present invention;

[0094] FIG. 5 is a mapping diagram of a 4×8 cross polarized antenna array disposed on a base station side to a RS port according to one embodiment of the present invention;

[0095] FIG. 6 is a structure diagram illustrating a processing apparatus used in a UE according to one embodiment of the present invention;

[0096] FIG. 7 is a structure diagram illustrating a processing apparatus used in a base station according to one embodiment of the present invention.

DETAILED DESCRIPTION

[0097] The following description with reference to the accompanying drawings is provided to explain the exemplary embodiments of the invention. Note that in the case of no conflict, the embodiments of the present invention and the features of the embodiments may be arbitrarily combined with each other.

Embodiment I

[0098] Embodiment I illustrates a flowchart of a CSI feedback, as shown in FIG. 2. In FIG. 2, a cell maintained by a base station N is a serving cell of a UE U2. In FIG. 2, the step in a square frame identified by F1 is an optional step.

[0099] For the base station N1, in step S11, the method involves transmitting a downlink reference signal in a first RS resource and a second RS resource; in step S12, the method involves receiving a first CI and a first index; in step S13, the method involves determining a downlink channel parameter.

[0100] For the UE U2, in step S21, the method involves receiving a downlink reference signal in a first RS resource and a second RS resource; in step S22, the method involves determining a target RS resource, wherein the target RS resource is the first RS resource or the second RS resource; in step S23, the method involves feeding back a first CI and a first index.

[0101] In Embodiment I, the first RS resource includes N1 RS ports, the second RS resource includes N2 RS ports, N1 is a positive integer greater than 1, and N2 is a positive integer greater than 1. A reference RS of the first CI is the target RS resource, the target RS resource is the first RS resource or the second RS resource, and the first index indicates the target RS resource.

[0102] In a first exemplary embodiment of Embodiment I, the base station N1 transmits an uplink scheduling DCI in step S110; receives an A-CSI on a PUSCH. The UE U2 receives an uplink scheduling DCI in step S210; transmits an A-CSI on a PUSCH. Wherein the uplink scheduling DCI includes a CSI scheduling bit, the CSI scheduling bit indicates one of the first RS resource and the second RS resource, and a reference RS of the A-CSI is a RS resource indicated by the CSI scheduling bit. The A-CSI includes at least one of {CI, CQI}.

[0103] In a second exemplary embodiment of Embodiment I, transmitting resources of the first CI and the second CI are orthogonal on a time domain. The first CI and the second CI occupy the same PUCCH resource in a sub frame. The second CI is a latest CI fed back by the UE U2, the reference RS of which is a RS resource in {the first RS resource, a second RS resource} and other than the target RS resource.

[0104] In a third exemplary embodiment of Embodiment I, the first index is one bit, and the first index identifies that the target RS resource is the first RS resource or the second RS resource.

[0105] In a fourth exemplary embodiment of Embodiment I, a pattern of the RS port inside a PRBP is a pattern of a CSI-RS port inside the PRBP.

[0106] In a fifth exemplary embodiment of Embodiment I, the UE U2 feeds back a first CQI in the step S23, and the base station N1 receives a first CQI in the step S23. Wherein the first CQI is calculated out under a condition that the UE U2 assumes that a PMI value corresponding to the CI in a reported CI set is adopted by the base station N1, and a reference RS of the first CQI includes the first RS resource and the second RS resource. The reported CI set includes the first CI and a second CI. The second CI is a latest CI fed back by the UE U2, the reference RS of which is a RS resource in {the first RS resource, the second RS resource} and other than the target RS resource.

Embodiment II

[0107] Embodiment II is a pattern of a first RS resource and a second RS resource inside a PRBP, as shown in FIG. 3, wherein RE identified by a number X corresponds to a RS port x—two Res on the same sub carrier adjacent time domain adopt OCC (orthogonal covering code). In FIG. 3, the first RS resource and the second RS resource occupy CSI-RS resources in the LTE, as shown by a square identified by a slash in FIG. 3.

[0108] In Embodiment II, the first RS resource includes RS ports {1, 2, 3, 4}, and the second RS resource includes RS ports {5, 6, 7, 8}. The first RS resource and the second RS resource respectively occupy a time, frequency and code domain resource of one set of four CSI-RS ports.

Embodiment III

[0109] Embodiment III is a mapping diagram of a 4×4 cross polarized antenna array disposed on a base station side to a RS port, as shown in FIG. 4. In FIG. 4, a small square indicates a physical antenna, and a number therein indicates a RS port index corresponding to the physical antenna.

[0110] As shown in FIG. 4, four transmitting antennas in a first polarization direction of the same row are mapped to the same RS port by adopting a pre-coding manner (i.e. the four transmitting antennas respectively send signals of RS sequence of the same RS port through a phase rotation, and one virtual antenna is formed on a UE side). Similarly, four transmitting antennas in a second polarization direction of the same column are mapped to the same port by adopting a pre-coding manner.

[0111] In Embodiment, firstly, the base station transmits a downlink reference signal to a UE in a first RS resource and a second RS resource; then, the UE determines a target RS resource, wherein the target RS resource is the first RS resource or the second RS resource; the UE feeds back a first CI, a third CI, a first index and a first CQI to the base station; finally, the base station determines a downlink channel parameter.

[0112] In Embodiment, the first RS resource includes RS ports {1, 2, 3, 4} and the second RS resource includes RS ports {5, 6, 7, 8}. A reference RS of the first CI is the target RS resource, the target RS resource is the first RS resource or the second RS resource, and the first index indicates the target RS resource. The first CQI is calculated out under a condition that the UE U2 assumes that a PMI value corresponding to the CI in a reported CI set is adopted by a base station, and a reference RS of the first CQI includes the first RS resource and the second RS resource. The reported CI set includes {the first CI, a second CI, a third CI}. The second CI is a latest CI fed back by the UE, the reference RS of which is a RS resource in {the first RS resource, the second RS resource} and other than the target RS resource.

[0113] In a first exemplary embodiment of Embodiment III, a codebook space of the first CI is a codebook space corresponding a first PMI of 8Tx in the LTE, and a PMI value corresponding to the first CI is w.sub.4×b.sub.1.sup.1; a codebook space of the second CI is a codebook space corresponding a first PMI of 8Tx in the LTE, and a PMI value corresponding to second CI is w.sub.4×b.sub.2.sup.2; a codebook space of the third CI is a codebook space of 2Tx in the LTE, and a PMI value corresponding to third CI is w.sub.2×b.sub.3.sup.3. Firstly, the base station uses a Kronecker product calculation to obtain a pre-coding matrix W.sub.32×(b.sub.1.sub.b.sub.2.sub.b.sub.3.sub.)=w.sub.2×b.sub.3.sup.3(w.sub.4×b.sub.1.sup.1w.sub.4×b.sub.2.sup.2) of two dimension array antenna, wherein W.sub.32×(b.sub.1.sub.b.sub.2.sub.b.sub.3.sub.) reflects the phase information of the downlink channel from thirty-two antenna to the UE, the base station uses a first CQI lookup table to determine a margin a of the downlink channel, and the base station finally determine the downlink channel as a.Math.W.sub.32×(b.sub.1.sub.b.sub.2.sub.b.sub.3.sub.).

[0114] Embodiment IV is a mapping diagram of a 4×8 cross polarized antenna array disposed on a base station side to a RS port, as shown in FIG. 5. In FIG. 5, a small square indicates a physical antenna, and a number therein indicates a RS port index corresponding the physical antenna (one physical antenna transmits a RS sequence of two ports).

[0115] As shown in FIG. 5, four transmitting antennas in the same column are mapped to the same RS port by adopting a pre-coding manner—RS ports {1-4}. Similarly, four transmitting antennas in the same row are mapped to the same RS port by adopting a pre-coding manner—RS port {5-8}.

[0116] Firstly, the base station transmits a downlink reference signal to a UE in a first RS resource and a second RS resource; the UE determines a target RS resource, wherein the target RS resource is the first RS resource or the second RS resource; the UE feeds back a first CI, a first index and a first CQI to the base station; the base station finally determines a downlink channel parameter.

[0117] In Embodiment IV, the first RS resource includes RS ports {1, 2, 3, 4} and the second RS resource includes RS ports {5, 6, 7, 8}. A reference RS of the first CI is the target RS resource, the target RS resource is the first RS resource or the second RS resource, and the first index indicates the target RS resource. The first CQI is calculated out under a condition that the UE U2 assumes that a PMI value corresponding to the CI in a reported CI set is adopted by a base station, and a reference RS of the first CQI includes the first RS resource and the second RS resource. The reported CI set includes {the first CI, a second CI}. The second CI is a latest CI fed back by the UE, the reference RS of which is a RS resource in {the first RS resource, the second RS resource} and other than the target RS resource.

[0118] In a first exemplary embodiment of Embodiment IV, a codebook space of the first CI is a codebook space corresponding of 8Tx in the LTE; a codebook space of the second CI is a codebook space of 4Tx in the LTE.

Embodiment V

[0119] Embodiment V is a structure diagram illustrating a processing apparatus used in a UE, as shown in FIG. 6. In FIG. 6, the processing apparatus 300 in the UE mainly includes a first receiving module 301, a first determining module 302, and a first transmitting module 303.

[0120] The first receiving module 301 is used for receiving a downlink reference signal in a first RS resource and a second RS resource; the first determining module 302 is used for determining a target RS resource, wherein the target RS resource is the first RS resource or the second RS resource; the first transmitting module 303 is used for feeding back a first CI and a first index.

[0121] In Embodiment V, the first RS resource includes N1 RS ports, the second RS resource includes N2 RS ports, a reference RS of the first CI is the target RS resource, the first index indicates the target RS resource, N1 is a positive integer greater than 1, and N2 is a positive integer greater than 1. Transmitting resources of the first CI and the second CI are orthogonal on a time domain. The first CI and the second CI occupy the same PUCCH resource in a sub frame. The second CI is a latest CI fed back by the UE, the reference RS of which is a RS resource in {the first RS resource, a second RS resource} and other than the target RS resource.

[0122] In a first exemplary embodiment of Embodiment V, a sum of the N1 and the N2 does not exceed eight.

[0123] In a second exemplary embodiment of Embodiment V, a codebook space of the first CI is a codebook space corresponding to a first PMI of 8Tx in the LTE or a codebook space of 4Tx in the LTE, and a codebook space of the second CI is a codebook space corresponding to a first PMI of 8Tx in the LTE or a codebook space of 4Tx in the LTE.

[0124] In a third exemplary embodiment of Embodiment V, the receiving module 301 is further used for receiving an uplink scheduling DCI, wherein the uplink scheduling DCI includes a CSI scheduling bit; the transmitting module 303 is further used for transmitting an A-CSI on a PUSCH. Wherein the CSI scheduling bit indicates one of the first RS resource and the second RS resource, a reference RS of the A-CSI is a RS resource indicated by the CSI scheduling bit; the A-CSI includes at least one of {CI, CQI}.

Embodiment VI

[0125] Embodiment VI is a structure diagram illustrating a processing apparatus used in a base station (eNB), as shown in FIG. 7. In FIG. 7, the processing apparatus 400 in the eNB mainly includes a second transmitting module 401, a second receiving module 402 and a second determining module 403.

[0126] The second transmitting module 401 is used for transmitting a downlink reference signal in a first RS resource and a second RS resource; the second receiving module 402 is used for receiving a first CI and a first index; the second determining module 403 is used for determining a downlink channel parameter.

[0127] In Embodiment VI, the first RS resource includes N1 RS ports, the second RS resource includes N2 RS ports, N1 is a positive integer greater than 1, and N2 is a positive integer greater than 1. A reference RS of the first CI is the target RS resource, the target RS resource is the first RS resource or the second RS resource, and the first index indicates the target RS resource. Transmitting resources of the first CI and the second CI are orthogonal on a time domain. The first CI and the second CI occupy the same PUCCH resource in a sub frame. The second CI is a latest CI fed back by the transmitting UE, the reference RS of which is a RS resource in {the first RS resource, a second RS resource} and other than the target RS resource.

[0128] In a first exemplary embodiment of Embodiment VI, the N1 is one of {1, 2, 4, 8} and the N2 is one of {1, 2, 4, 8}. The first RS resource occupies a time, frequency and code domain resource of one set of N1 CSI-RS ports, and the second RS resource occupies a time, frequency and code domain resource of one set of N2 CSI-RS ports.

[0129] In a second exemplary embodiment of Embodiment VI, a codebook space of the first CI is a codebook space corresponding to a first PMI of 8Tx in the LTE or a codebook space of 4Tx in the LTE, and a codebook space of the second CI is a codebook space corresponding to a first PMI of 8Tx in the LTE or a codebook space of 4Tx in the LTE.

[0130] In a third exemplary embodiment of Embodiment VI, the second transmitting module 401 is further used for transmitting an uplink scheduling DCI, wherein the uplink scheduling DCI includes a CSI scheduling bit; the second receiving module 402 is further used for receiving an A-CSI on a PUSCH. Wherein the CSI scheduling bit indicates one of the first RS resource and the second RS resource, a reference RS of the A-CSI is a RS resource indicated by the CSI scheduling bit; the A-CSI includes at least one of {CI, CQI}.

[0131] Those of ordinary skill will be appreciated that all or part of the above method may be accomplished by a program instructing related hardware. The program may be stored in a computer-readable storage medium, such as read-only memory, a hard disk or CD-ROM. Alternatively, all or part of the steps of the above-described embodiments may be accomplished by one or more integrated circuits. Accordingly, each module in the above-described embodiments may be accomplished by hardware implementation, or may also be realized by the form of software modules. The present invention is not limited to any particular form of combination of software and hardware.

[0132] Although the present invention is illustrated and described with reference to specific embodiments, those skilled in the art will understand that many variations and modifications are readily attainable without departing from the spirit and scope thereof as defined by the appended claims and their legal equivalents.