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US-12627352-B2 - Reference signaling design and configuration

US12627352B2US 12627352 B2US12627352 B2US 12627352B2US-12627352-B2

Abstract

Structures and configurations for coherent joint transmission (CJT) codebook are disclosed. In an implementation, a method of wireless communication includes determining, by a communication device, N channel status information reference signal port groups, wherein N is a positive integer, receiving, by the communication device, channel status information reference signals on the N channel status information reference signal port groups, determining, by the communication device, C precoding matrices based on the received channel status information reference signals on the N channel status information reference signal port groups, wherein C is a positive integer, and transmitting, by the communication device, a report including a precoding matrix indicator that includes information about a first type of vector, wherein the first type of vector includes C elements, and each of the C elements corresponds to one first type of frequency domain unit.

Inventors

  • Shujuan Zhang
  • Bo Gao
  • Ke Yao
  • Shijia SHAO
  • Wenjun YAN
  • Zhaohua Lu

Assignees

  • ZTE CORPORATION

Dates

Publication Date
20260512
Application Date
20231207

Claims (20)

  1. 1 . A method of communication, comprising: determining, by a communication device, N channel status information reference signal port groups, wherein N is a positive integer; receiving, by the communication device, channel status information reference signals on the N channel status information reference signal port groups; determining, by the communication device, C precoding matrices based on the received channel status information reference signals on the N channel status information reference signal port groups, wherein C is a positive integer; and transmitting, by the communication device, a report including a precoding matrix indicator that includes information about a first type of vector, wherein the first type of vector includes C elements, and each of the C elements corresponds to one first type of frequency domain unit, wherein each of the C precoding matrices corresponds to one first type of frequency domain unit and includes N sub-precoding matrices each of which corresponds to one of the N channel status information reference signal port groups, wherein the report further includes one or more CSI-RS resource indicators (CRIs) corresponding to the precoding matrix indicator, the N sub-precoding matrices correspond to a same set of layers, each of the N channel status information reference signal port groups corresponds to one CSI-RS resource respectively.
  2. 2 . The method of claim 1 , wherein the precoding matrix indicator further includes information about a second type of vector, wherein the second type of vector includes D elements, and each of the D elements corresponds to a second type of frequency domain unit, wherein D is a positive integer.
  3. 3 . The method of claim 2 , wherein, for each of the N channel status information reference signal port groups, C sub-precoding matrices are determined according to one vector of the first type of vectors and one or more sets of the second type of vectors, wherein each of the C sub-precoding matrices is associated with one of the C precoding matrices, and wherein each of C sub-precoding matrices is determined by one element of the one vector of the first type of vectors and one element of each vector of the second type of vectors in the one or more sets of the second type of vectors.
  4. 4 . The method of claim 1 , wherein one element with index t 1 of the first type of vector includes y t 1 , l , j ( 1 ) expressed by y t 1 , l , j ( 1 ) = e j ⁢ 2 ⁢ π ⁢ n 4 , l , j ⁢ t 1 F 4 , n 4,l,j ∈{0, 1 . . . , F 4 −1}, t 1 =0, 1 . . . , F 4 −1 or y t 1 ( 1 ) = exp j ⁢ 2 ⁢ π ⁢ n 4 ⁢ t 1 F 4 , n 4 ∈{0, 1, . . . F 4 −1}, t 1 =0, 1 . . . , F 4 , wherein F 4 is a number of first type of frequency domain units.
  5. 5 . The method of claim 2 , wherein one element with index t 2 of the second type of vector includes y t 2 ( 2 ) expressed by: y t 2 ( 2 ) = e j ⁢ 2 ⁢ π ⁡ ( n 3 f * R 1 ) ⁢ t 2 F 3 * R 1 , n 3 f ∈{ 0 , 1 , . . . F 3 −1}, t 2 =0, 1, . . . F 3 −1, ƒ=0, 1, . . . M j −1 wherein M j is a number of second type of vectors, F 4 is the number of the first type of frequency domain units and F 4 equals C, F 3 is the number of the second type of frequency domain units and F 3 equals D, wherein F 4 ≥F 3 .
  6. 6 . The method of claim 2 , wherein: the precoding matrix includes an index of the first frequency domain without remapping, and the precoding matrix includes an index of the second frequency domain after remapping with regard to a reference second type of frequency domain vector.
  7. 7 . The method of claim 1 , further comprising: receiving, by the communication device, a signaling that includes at least one of a first channel status information (CSI) parameter for each of the N channel status information reference signal port groups, a second CSI parameter shared by the N channel status information reference signal port groups, wherein the first CSI parameter includes a codebook restriction, and the second CSI parameter includes a rank restriction.
  8. 8 . The method of claim 1 , wherein the report includes ┌log 2 R 1 ┐ bits corresponding to one vector of the first type of vectors, wherein R 1 is a number of the first type of frequency units in one second type of frequency domain unit.
  9. 9 . The method of claim 1 , wherein a column with index l of a sub matrix with index j of one precoding matrix with index t 1 includes one of a plurality of formats, including: w t 1 , j l = [ w t 1 , 0. l j w t 1 , 1. l j ] = 1 β l , j [ ∑ i = 0 L j - 1 ⁢ v i , j ⁢ p l , 0 , j ( 1 ) ⁢ ϕ j ( 4 ) ⁢ ∑ f = 0 M j - 1 ⁢ y t 1 , l , f , j ( 1 ) ⁢ p l , i , f , j ( 2 ) ⁢ ϕ l , i , f , j ( 2 ) ∑ i = 0 L j - 1 ⁢ v i , j ⁢ p l , 1 , j ( 1 ) ⁢ ϕ j ( 4 ) ⁢ ∑ f = 0 M j - 1 ⁢ y t 1 , l , f , j ( 1 ) ⁢ p l , i + L , f , j ( 2 ) ⁢ ϕ l , i + L , f , j ( 2 ) ] , wherein y t 1 , l , f , j ( 1 ) is an element of a first type of vector specific to layer l, first type of vector index ƒ and CSI-RS port group index j, y t 1 , l , j ( 1 ) is an element of a first type of vector specific to layer l, and CSI-RS port group index j.
  10. 10 . The method of claim 9 , wherein the precoding matrix indicator includes i l * , f l * , j l * corresponding to a maximum value among amplitudes P l , i , f , j ( 2 ) , for each layer l.
  11. 11 . The method of claim 9 , wherein the precoding matrix indicator includes N−1 of ϕ j ( 4 ) without reporting ϕ 0 ( 4 ) = 1.
  12. 12 . The method of claim 9 , wherein the precoding matrix indicator includes one of: one bitmap for each CSI port group of each layer to indicate non-zero values of p l , i , f , j ( 2 ) ⁢ and ⁢ ϕ l , i , f , j ( 2 ) of each CSI port group of the corresponding layer; or one bitmap for each layer to indicate the non-zero values of p l , i , f , j ( 2 ) ⁢ and ⁢ ϕ l , i , f , j ( 2 ) of the corresponding layer, wherein a total number of value 1 in one bitmap is not larger than a first threshold; a total number of value 1 in multiple bitmaps corresponding to multiple channel status information reference signal port group indices and one layer is not larger than a third threshold; or a total number of value 1 in multiple bitmaps corresponding to multiple channel status information reference signal port group indices and multiple layers is not larger than a fourth threshold.
  13. 13 . The method of claim 7 , wherein the precoding matrix indicator includes M j −1 of n 3 , l , j f for one CSI-RS port group j, where n 3 , l , j f is after a remapping operation, wherein the remapping operation refers to at least one of: n 3 , l , j f = ( n 3 , l , j f - n 3 , l , j f * ) ⁢ mod ⁢ F 3 .
  14. 14 . A method of communication, comprising: transmitting, by a communication node, channel status information reference signals on N channel status information reference signal port groups, wherein N is a positive integer; receiving, by the communication node, from a communication device, a report including a precoding matrix indicator that includes information about a first type of vector, wherein the first type of vector includes C elements, and each of the C elements corresponds to one first type of frequency domain unit, wherein C is a positive integer; and determining, by the communication node, C precoding matrices based on the received report, wherein each of the C precoding matrices corresponds to one first type of frequency domain unit and includes N sub-precoding matrices each of which corresponds to one of the N channel status information reference signal port groups, wherein the report further includes one or more CSI-RS resource indicators (CRIs) corresponding to the precoding matrix indicator, the N sub-precoding matrices correspond to a same set of layers, each of the N channel status information reference signal port groups corresponds to one CSI-RS resource respectively.
  15. 15 . The method of claim 14 , wherein one element with index t 1 of the first type of vector includes y t 1 , l , j ( 1 ) expressed by y t 1 , l , j ( 1 ) = e j ⁢ 2 ⁢ π ⁢ n 4 , l , j ⁢ t 1 F 4 , n 4,l,j ∈{0, 1, . . . , F 4 −1}, t 1 =0, 1, . . . , F 4 −1 or y t 1 ( 1 ) = exp j ⁢ 2 ⁢ π ⁢ n 4 ⁢ t 1 F 4 , n 4 ∈{0, 1, . . . F 4 −1}, t 1 =0, 1 . . . , F 4 , wherein F 4 is a number of first type of frequency domain units.
  16. 16 . The method of claim 15 , wherein one element with index t 2 of a second type of vector includes γ t 2 ( 2 ) expressed by: y t 2 ( 2 ) = e j ⁢ 2 ⁢ π ⁡ ( n 3 f * R 1 ) ⁢ t 2 F 3 * R 1 , n 3 f ∈{ 0 , 1 , . . . F 3 −1}, t 2 =0, 1, . . . F 3 −1, ƒ=0, 1, . . . M j −1 wherein M j is a number of the second type of vectors, F 4 is the number of the first type of frequency domain units and F 4 equals C, F 3 is the number of the second type of frequency domain units and F 3 equals D, wherein F 4 ≥F 3 .
  17. 17 . The method of claim 14 , wherein the report includes ┌log 2 R 1 ┐ bits corresponding to one vector of the first type of vectors, wherein R 1 is a number of the first type of frequency units in one second type of frequency domain unit.
  18. 18 . The method of claim 14 , wherein the precoding matrix indicator includes one of: one bitmap for each CSI port group of each layer to indicate non-zero values of p l , i , f , j ( 2 ) ⁢ and ⁢ ϕ l , i , f , j ( 2 ) of each CSI port group of the corresponding layer; or one bitmap for each layer to indicate the non-zero values of p l , i , f , j ( 2 ) ⁢ and ⁢ ϕ l , i , f , j ( 2 ) of the corresponding layer, wherein a total number of value 1 in one bitmap is not larger than a first threshold; a total number of value 1 in multiple bitmaps corresponding to multiple channel status information reference signal port group indices and one layer is not larger than a third threshold; or a total number of value 1 in multiple bitmaps corresponding to multiple channel status information reference signal port group indices and multiple layers is not larger than a fourth threshold.
  19. 19 . A communication device, comprising at least one processor configured to perform a method comprising: determining N channel status information reference signal port groups, wherein N is a positive integer; receiving channel status information reference signals on the N channel status information reference signal port groups; determining C precoding matrices based on the received channel status information reference signals on the N channel status information reference signal port groups, wherein C is a positive integer; and transmitting a report including a precoding matrix indicator that includes information about a first type of vector, wherein the first type of vector includes C elements, and each of the C elements corresponds to one first type of frequency domain unit, wherein each of the C precoding matrices corresponds to one first type of frequency domain unit and includes N sub-precoding matrices each of which corresponds to one of the N channel status information reference signal port groups, wherein the report further includes one or more CSI-RS resource indicators (CRIs) corresponding to the precoding matrix indicator, the N sub-precoding matrices correspond to a same set of layers, each of the N channel status information reference signal port groups corresponds to one CSI-RS resource respectively.
  20. 20 . The communication device of claim 19 , wherein the precoding matrix indicator further includes information about a second type of vector, wherein the second type of vector includes D elements, and each of the D elements corresponds to a second type of frequency domain unit, wherein D is a positive integer.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS This application is a continuation of and claims priority to International PCT Application No. PCT/CN2022/090647, filed Apr. 29, 2022, the disclosure of which is hereby incorporated by reference herein in its entirety. TECHNICAL FIELD This patent document is directed generally to wireless communications. BACKGROUND Mobile communication technologies are moving the world toward an increasingly connected and networked society. The rapid growth of mobile communications and advances in technology have led to greater demand for capacity and connectivity. Other aspects, such as energy consumption, device cost, spectral efficiency, and latency are also important to meeting the needs of various communication scenarios. Various techniques, including new ways to provide higher quality of service, longer battery life, and improved performance are being discussed. SUMMARY This patent document describes, among other things, techniques for structures and configurations for coherent joint transmission (CJT) codebook. In one aspect, a method of data communication is disclosed. The method includes determining, by a communication device, N channel status information reference signal port groups, wherein N is a positive integer, receiving, by the communication device, channel status information reference signals on the N channel status information reference signal port groups, determining, by the communication device, C precoding matrices based on the received channel status information reference signals on the N channel status information reference signal port groups, wherein C is a positive integer, and transmitting, by the communication device, a report including a precoding matrix indicator that includes information about a first type of vector, wherein the first type of vector includes C elements, and each of the C elements corresponds to one first type of frequency domain unit, wherein each of the C precoding matrices corresponds to one first type of frequency domain unit and includes N sub-precoding matrices each of which corresponds to one of the N channel status information reference signal port groups. In another aspect, a method of data communication is disclosed. The method includes transmitting, by a communication node, channel status information reference signals on N channel status information reference signal port groups, wherein N is a positive integer, receiving, by the communication node, from a communication device, a report including a precoding matrix indicator that includes information about a first type of vector, wherein the first type of vector includes C elements, and each of the C elements corresponds to one first type of frequency domain unit, wherein C is a positive integer, determining, by the communication node, C precoding matrices based on the received report, wherein each of the C precoding matrices corresponds to one first type of frequency domain unit and includes N sub-precoding matrices each of which corresponds to one of the N channel status information reference signal port groups. In another example aspect, a wireless communication apparatus comprising a processor configured to implement an above-described method is disclosed. In another example aspect, a computer storage medium having code for implementing an above-described method stored thereon is disclosed. These, and other, aspects are described in the present document. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 shows an example of a wireless communication system based on some example embodiments of the disclosed technology. FIG. 2 is a block diagram representation of a portion of an apparatus based on some embodiments of the disclosed technology. FIG. 3 shows an example of a subband that includes 8 physical resource blocks (PRBs) where one second type of frequency domain units includes 4 PRBs, one first type of frequency domain unit includes one PRB, and a second type of frequency domain unit includes 4 first type frequency domain units based on some embodiments of the disclosed technology. FIG. 4 shows an example relationship between CSI-RS resource groups, CSI-RS port groups and transmitter-receiver points (TRPs) based on some embodiments of the disclosed technology. FIG. 5 shows an example of a process for wireless communication based on some example embodiments of the disclosed technology. FIG. 6 shows another example of a process for wireless communication based on some example embodiments of the disclosed technology. DETAILED DESCRIPTION Section headings are used in the present document only for ease of understanding and do not limit scope of the embodiments to the section in which they are described. Furthermore, while embodiments are described with reference to 5G examples, the disclosed techniques may be applied to wireless systems that use protocols other than 5G or 3GPP protocols. FIG. 1 shows an example of a wireless communication system (e.g., a long term evolution (LTE), 5G or N