A Channel Estimation Method

Abstract

The present application discloses a channel estimation method, including: configuring reference signals for two paired users respectively, wherein the difference between the cyclic shift factors adopted by the reference signals of the two paired users is π; arbitrarily selecting one of the The user uses the user's reference signal to perform channel estimation on the received signal on each pilot subcarrier k in the currently received pilot symbol l, and obtains the least squares method LS channel estimation result of the received signal; using the pairing Orthogonal characteristics of the parity element of the user's reference signal, despreading the LS channel estimation result to obtain the channel estimation result of each user with the signal of another paired user eliminated; for each user, according to The MMSE channel estimation criterion is to filter the channel estimation result of the user whose signal of another paired user has been eliminated, to obtain the channel estimation result of the user whose noise has been eliminated. The present invention can reduce the calculation amount of channel estimation and is easy to implement.

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] [0005] in, is the length of the reference signal sequence r, n is the sequence element number, base sequence The value of the nth element in , α is the cyclic shift factor, 0≤i<N, in the LTE uplink demodulation reference signal, N=12. [0006] According to formula (1), different reference sequences obtained from the same base ...

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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