信道误差下MIMO鲁棒迫零接收机

Robust MIMO zero-forcing receiver in the presence of the channel estimation error

提出了一种应用于多输入多输出(MIMO)系统的新的迫零接收机.在接收端已知信道信息估计值的情况下,通过引入信道误差的统计信息,修正了传统迫零接收的滤波系数.当接收端无法获取正确的信道信息时,该接收机受信道信息误差的影响较传统的迫零接收机小,具有较好的鲁棒性.仿真表明在同等误差条件下的误比特率性能得到改善.对于未编码4发4收多天线系统,在采用QPSK调制,信道误差系数为0.05的情况下,高信噪比下传统迫零接收误比特率为5×10-3,所提接收机的误比特率为1.8×10-3,有效的降低了错误平层.采用QPSK调制时,当估算的信道估计误差在真实误差3倍的范围内该算法均能有效的工作.

A robust zero-forcing receiver in the Multiple Input Multiple Output （MIMO） channel with a channel estimation error is presented. By considering the statistics of channel estimation errors, the coefficient of zero-forcing filter is modified with the estimated channel information. The presented receiver is more robust than the traditional ZF receiver in the presence of inaccurate channel information in the receiver. Simulation results show that the BER （bit error rate） is improved and that the error floor is lower than that of the traditional receiver with the same estimation error. In the uncoded 4 × 4MIMO system with QPSK modulation and if the channel estimation error coefficient equals 0. 05, the BER of the traditional ZF receiver is 5×10^-3 and that of the presented receiver is 1.8×10^-3 at a high SNR. It is also shown that the system with QPSK modulation can work effectively when the estimated channel error is smaller than three times the real channel error.