Generation method of vector quantization code book

Abstract

The invention provides a generation method of a vector quantization code book. In the method, a global optimization method based on a random relaxation technology is introduced; and while iteratively updating the code book every time, random disturbance is generated and added to a corresponding code word, thus local convergence is effectively avoided during the process of updating the code book. The method can further rationally optimize a code book structure and bit positions of the code word according to the inherent characteristic of channel statistical distribution of a wireless communication system and the requirement on orthogonality of user scheduling in a base station in an MIMO system on the selected users. In addition, a method for expanding the code book is also introduced in order to improve the robustness of the code book in a multi-channel statistical distribution environment, and the size of the code book can be flexibly adjusted according to specific conditions. As the antenna number of the base station and downlink user equipment is greatly increased based on the demand of the development of the future communication system, the method can generate reserved interfaces for the future code book, and can achieve higher quantization and system performance with lower complexity even though the method is used in high-dimensional vector quantization.

Description

technical field [0001] The present invention relates to the technical field of wireless communication systems, and relates to a method for generating a codebook required for vector quantization of channel state information. According to the present invention, a scalable and scalable universal vector quantization codebook can be generated to enable downlink users to feed back to a base station Channel state information. Background technique [0002] The new-generation mobile communication system (4G) needs to provide high data rates. Under the condition of limited frequency resources, high transmission rates should be provided as much as possible. This requires the consideration of technologies with high spectrum utilization. Ideally, using multiple-input multiple-output (MIMO) technology, the channel capacity can increase linearly with the increase in the number of antennas. One of the most competitive technologies in In an actual system, in order to realize the high throu...

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Problems solved by technology

[0008] The traditional CSI vector quantization method is based on the Lloyd algorithm to obtain a locally optimized codebook, and the codebook design of vector quantization is a typical nonlinear problem, so it is difficult to obtain a global optimal solution with a local optimization method, which will increase the CSI The quantization error of quantization affects the throughput of the system;

[0009] The training vector sequence is generated by random numbers subject to independent complex Gaussian distribution, so that the codebook generated by training has good characteristics for channels subject to complex Gaussian distribution, but the quantization performance of channels with other statistical distributions is not ideal;

[0010] The size of the codebook is fixed. If the reason of quantization accuracy and system throughput is considered, blindly expanding the codebook will cause great pressure on the limited storage space of downlink users;

[0011] It does not take into account that with the development of communication systems in the future, the number of antennas of base stations and downlink users will increase greatly. If only vector quantization is performed directly, the complexity of codebook design and codeword search will increase exponentially. Dimensional channel vectors are simply truncated to become a set of short vectors, and then return to the original scalar quantization, sacrificing more performance in exchange for reduced complexity;

[0012] In addition, in view of the inherent characteristics of the statistical distribution of channels in wireless communication systems and the requirement of orthogonality between selected users for user scheduling by base stations in MIMO systems, there is still room for optimization and improvement in the codebook structure

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