Channel estimation method

Abstract

The invention discloses a channel estimation method. The method comprises the following steps: respectively configuring reference signals for two paired users, wherein the difference between circular shift factors employed by the reference signals of the two paired users is pi; randomly selecting one user, by use of the reference signals of the user, performing channel estimation on received signals on each pilot frequency subcarrier k in a currently received pilot frequency symbol l to obtain a LS channel estimation result of the received signals; by use of the orthogonal characteristic of odd element and even elements in the reference signals of the paired users, performing despreading processing to obtain a channel estimation result of each user after the signals of the other paired user are eliminated; and for each user, according to an MMSE channel estimation criterion, filtering the channel estimation result of the user after the signals of the other paired user are eliminated to obtain the channel estimation result of the user after noise is eliminated. The channel estimation method can reduce the computation of channel estimation and is easy to realize.

Description

technical field [0001] The present invention relates to channel estimation technology in mobile communication system, in particular to a channel estimation method of MU-MIMO system. Background technique [0002] In a MU-MIMO communication system, paired users occupy the same time-frequency resources. The uplink MU-MIMO transmission mechanism of two users is defined in the R8 standard of the LTE system. By configuring different parameters, the uplink reference signal sequences of the two users are orthogonal. [0003] Each element r(n) in the LTE uplink reference sequence R can be obtained according to the following formula: [0004] r ( n ) = e jαn r ‾ ( n ) - - - ( 1 ) [0005] in, is the length of the...

AI Technical Summary

Problems solved by technology

[0022] 1. It is necessary to calculate the LS channel estimation for each user of the MU separately The corresponding channel estimation has a large amount of computation

[0023] 2. Since there is not only noise interference in the received signal of MU users, but also useful signal interference from other users. Therefore, compared with the filtering processing of single user (SU) user signals, it is also necessary to remove other users during filtering. Correspondingly, a higher-dimensional MMSE filter bank matrix is ​​required for filtering to obtain better demodulation characteristics, which leads to the complexity of system implementation

In addition, since there are multiple users and single users in the MU-MIMO communication system at the same time, when multiple users and single users cannot share a set of MMSE filter bank matrices, correspondingly, it will also bring certain problems to the realization of the system. the complexity

[0024] To sum up, when using the above simplified channel estimation method to perform channel estimation for paired users, there are problems such as large amount of computation, complex implementation, and high cost.

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