	US 12,244,386 B2
	Method and apparatus for acquiring precoding matrix index and storage medium
Qing Bian, Guangdong (CN)
Assigned to SANECHIPS TECHNOLOGY CO., LTD., Guangdong (CN)
Appl. No. 17/622,741
Filed by ZTE CORPORATION, Guangdong (CN)
PCT Filed Sep. 21, 2020, PCT No. PCT/CN2020/116368 § 371(c)(1), (2) Date Dec. 24, 2021, PCT Pub. No. WO2021/057634, PCT Pub. Date Apr. 1, 2021.
Claims priority of application No. 201910897558.7 (CN), filed on Sep. 23, 2019.
Prior Publication US 2022/0166483 A1, May 26, 2022
Int. Cl. H04B 7/06 (2006.01); H04B 7/0417 (2017.01); H04B 7/0456 (2017.01)

CPC H04B 7/0639 (2013.01) [H04B 7/0417 (2013.01); H04B 7/0456 (2013.01)]

15 Claims

1. A method for acquiring a precoding matrix index (PMI), comprising:

searching a first group of PMI parameters according to first initial values of a PMI parameter set, and determining the first group of PMI parameters corresponding to the maximum capacity as a first group of reported values;

generating second initial values of the PMI parameter set according to the first group of reported values and the first initial values of the PMI parameter set;

searching a second group of PMI parameters according to the second initial values of the PMI parameter set, and determining the second group of PMI parameters corresponding to the maximum capacity as a second group of reported values;

generating third initial values of the PMI parameter set according to the second group of reported values and the second initial values of the PMI parameter set; and

searching a third group of PMI parameters according to the third initial values of the PMI parameter set, and determining the third group of PMI parameters corresponding to the maximum capacity as a third group of reported values,

wherein before the step of searching the first group of PMI parameters according to the first initial values of the PMI parameter set, the method further comprises:

generating the first initial values of the PMI parameter set according to current configuration parameters,

wherein the configuration parameters comprise: rank indicator (RI), antenna configuration and codebook configuration,

wherein the first initial values of the PMI parameter set comprise initial values of the following: a first wideband precoding indication first PMI1, a second wideband precoding indication first PMI2, a third wideband precoding indication first PMI3, a second antenna panel fourth wideband precoding indication first PMI4_1, a third antenna panel fourth wideband precoding indication first PMI4_2, a fourth antenna panel fourth wideband precoding indication first PMI4_3, and a subband precoding indication second PMI, which are respectively denoted as: i11_rand, i12_rand, i13_rand, i14_1_rand, i14_2_rand, i14_3_randand i2_rand,

wherein before the step of searching the first group of PMI parameters according to the first initial values of the PMI parameter set, the method further comprises:

estimating a channel coefficient matrix and a noise variance matrix on each subcarrier according to pilot signals,

wherein after the step of generating the first initial values of the PMI parameter set and before the step of searching the first group of PMI parameters according to the first initial values of the PMI parameter set, the method further comprises:

generating a first PMI2 preset for pre-searching the first PMI2 according to the first initial values of the PMI parameter set;

calculating, according to the estimated channel coefficient matrix and noise variance matrix and the first PMI2 preset, channel capacities corresponding to respective PMI values in the first PMI2 preset;

selecting the first PMI2 corresponding to the maximum capacity and recording a value i12_saveof the first PMI2 corresponding to the maximum capacity; and

updating the first initial values of the PMI parameter set according to the recorded i12_save,

wherein after pre-searching the first PMI2 and before the step of searching the first group of PMI parameters according to the first initial values of the PMI parameter set, the method further comprises:

generating a first PMI4 preset for pre-searching a fourth wideband precoding indication first PMI4 according to the first initial values of the PMI parameter set;

calculating, according to the estimated channel coefficient matrix and noise variance matrix and the first PMI4 preset, channel capacities corresponding to respective PMI values in the first PMI4 preset;

selecting the first PMI4 corresponding to the maximum capacity and recording a value of the first PMI4 corresponding to the maximum capacity; and

updating the first initial values of the PMI parameter set according to the recorded value of the first PMI4 corresponding to the maximum capacity;

wherein the first PMI4 parameter comprises first PMI4_1, first PMI4_2 and first PMI4_3,

the step of generating the first PMI4 preset for pre-searching the first PMI4 comprises:

generating a first PMI4 preset with preset search rounds according to the first initial values of the PMI parameter set:

the first round uses a fixed initial i14 spacing pattern {a′, b′, c′} in a first group of patterns, the first calculation in the first round uses initial values comprising {i11_rand, i12_save, i13_rand, i14_1_rand+a′, i14_2_rand+b′, i14_3_rand+C′, i2_rand}, the N^thcalculation in the first round uses PMI parameters comprising {i11_rand, i12_save, i13_rand, (i14_1_rand+N−1+a′)mod(Numi14_1), (i14_2_rand+N−1+b′)mod(Numi14_2), (i14_3_rand+N−1+c′)mod(Numi14 _3), i2_rand}, until the fourth calculation in the first round;

the second round uses a random initial i14 spacing pattern {a″, b″, c″} in a second group of patterns, the first calculation in the second round uses initial values comprising {i11_rand, i12_save, i13_rand, i14_1_rand+a″, i14_2_rand+b″, i14_3_rand+C″, i2_rand}, the N^thcalculation in the second round uses PMI parameters comprising {i11_rand, i12_save, i13_rand, (i14 _1_rand+N−1+a″)mod(Numi14_1), (i14_2_rand+N−1+b″)mod(Numi14_2), (i14_3_rand+N−1+c″)mod(Numi14_3), i2_rand}, until the fourth calculation in the second round; and

the preset search round uses a random initial i14 spacing pattern {a′″, b′″, c′″} in a third group of patterns, the first calculation in the preset search round uses initial values comprising {i11_rand, i12_save, i13_rand, i14_1_rand+a′″, i14_2_rand+b′″, i14_3_rand+C′″, i2_rand}, the N^thcalculation in the preset search round uses PMI parameters comprising {i11_rand, i12_save, i13_rand, (i14_1_rand+N−1+a′″)mod(Numi14_1), (i14_2_rand+N−1+b′″)mod(Numi14_2), (i14_3_rand+N−1+c′″)mod(Numi14_3), i2_rand}, until the fourth calculation in the preset search round.