MIMO precoding enabling spatial multiplexing, power allocation and adaptive modulation and coding

摘要

In a closed-loop wireless communication system, a codebook-based feedback mechanism is provided to enable non-unitary precoding for multi-stream transmission, where in each stream is optimized with suitable transmission power allocation and AMC. The codebook-based feedback mechanism uses a precoding codebook having a power allocation matrix which is constrained to specify that beamforming always applies full power to a predetermined beam. With this constraint, a one-bit power allocation feedback index may be used to switch between beamforming and spatial multiplexing.

主权项

1. A method for precoding operation in a multiple-input, multiple-output (MIMO) wireless communication system, comprising:
estimating, using a first device, channel state information related to a transmission channel between a second device and the first device; identifying an adaptive modulation and coding (AMC) scheme, a precoding matrix, and a power allocation matrix based at least in part on the estimated channel state information; and transmitting information from the first device, the transmitted information comprising:
a first index indicative of the AMC scheme,a second index indicative of the precoding matrix, anda third index indicative of the power allocation matrix.