Patent ID: 11881919
Assignee: FRAUNHOFER GESELLSCHAFT ZUR FÖRDERUNG DER ANGEWANDTEN FORSCHUNG E.V.
Field: Telecommunications (Electrical engineering)
Classification: CPC H | IPC H

Claim 12:
13. A method performed by a network node (gNB) for receiving channel state information (CSI) feedback in the form of one or more CSI reports in a wireless communication system (A), the method comprising:
sending, to a user equipment (UE) higher layer configuration(s) of one or more downlink reference signals, and one or more CSI report configuration(s) associated with the downlink reference signal configuration(s), and a radio signal, the radio signal including the downlink reference signal(s) according to the one or more downlink reference signal configuration(s);
receiving, from the UE one or more CSI reports for one or more CSI report configurations;, wherein the one or more CSI reports comprises:
a precoding matrix based on the downlink reference signal(s) and two codebooks, the two codebooks including
a spatial codebook comprising one or more spatial domain (SD) basis components of a precoder, and
a delay codebook comprising one or more delay domain (DD) basis components of the precoder,

and one or more non-zero combining coefficients for complex combining of the one or more SD and DD basis vectors,, wherein each CSI report contains a selected precoding matrix in the form of a precoding matrix identifier, PMI, and a rank identifier, RI, indicating the transmission rank for the RI layers of the precoding matrix, and wherein each CSI report comprises two parts: CSI part 1 and CSI part 2, wherein CSI part 1 has a fixed payload size and comprises information indicating the size of the payload of CSI part 2, wherein CSI part 2 comprises at least the amplitude and phase information of the selected non-zero combining coefficients of the CSI report, wherein a bitmap of each layer is segmented into D bit-sequences with respect to the DD basis indices of the selected DD basis vectors, wherein each bit-sequence comprises 2U×1 bits which are associated with 2U spatial beams, wherein U denotes the number of selected SD basis vectors from the spatial codebook, and each DD basis index is associated with a delay vector from the delay codebook and, wherein the D bit-sequences are ordered with respect to one of two ordering scheme for the N3 DD basis indices, where N3 denotes the number of DD basis indices of the delay codebook, where the N3 DD basis indices are ordered as

0,1,N3−1,2,N3−2,3,N3−3,4,N3−4,5, . . ., according to a first ordering scheme, or where the N3 DD basis indices are ordered as

0,N3−1,1,N3−2,2,N3−3,3,N3−4,4,N3−5,5, . . ., according to a second ordering scheme, and wherein the ordering of the amplitude and phase information of the combining coefficients follows the ordering of the bit-sequences of the bitmaps of all RI layers, and wherein a portion, or the entirety, of CSI part 2 is available for omission from the CSI report.