Two-dimensional Interpolation Finite Feedback Method Based on Channel Prediction in LTE System

Abstract

The invention discloses a two-dimensional interpolation limited feedback method suitable for an LTE (Long Term Evolution) system, and the method belongs to the communication field. The method comprises the following steps of: estimating a channel matrix corresponding to current data frames by a receiving terminal according to pilot frequency information, and obtaining a channel prediction matrix through predicting a channel matrix corresponding to subsequent data frames; forming feedback data blocks by carrying out block processing according to subcarriers on the basis of the channel matrix; selecting optimal code words corresponding to four vertex positions of each feedback data block, carrying out time domain and frequency domain interpolation processing according to the optimal code words, and calculating optical rotational vectors corresponding to the feedback data blocks; and feeding back an optimal code word index and an optical rotational vector index back to a transmitting terminal by the receiving terminal so as to determine precoding matrixes corresponding to all subframes and subcarriers in each feedback data block, and realizing the precoding of the transmitting terminal. By adopting the method, the feedback quantity of limited feedback can be effectively reduced, the performance loss caused by feedback time delay on the system can be effectively restrained, and the system transmission performance can be improved.

Description

technical field [0001] The invention belongs to the communication field and relates to a two-dimensional interpolation limited feedback method based on channel prediction in an LTE system. Background technique [0002] LTE combines advanced wireless transmission technologies such as Multiple Input Multiple Output (MIMO) and Orthogonal Frequency Division Multiplexing (OFDM). Among them, MIMO multi-antenna technology realizes Parallel transmission and reception of multiple data streams at the same time and in the same frequency band greatly improves the frequency band utilization of the system and meets the needs of high-speed communication of the LTE system. As an efficient multi-carrier transmission technology, OFDM converts high-speed serial data streams into multiple low-speed parallel data streams through serial-to-parallel conversion. Since the sub-carriers are orthogonal to each other and the sub-channels overlap each other in the frequency domain, it can provide highe...

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Problems solved by technology

[0005] In a multi-user LTE system, since the number of users and the number of subcarriers for each user are relatively large, in order to obtain the optimal precoding matrix for each subcarrier of the user, the base station must adopt similar precoding feedback for each subcarrier The processing mechanism leads to excessive feedback, resulting in a great waste of system resources. Therefore, the method of reducing the precoding feedback overhead has been widely studied by the industry.

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