Aiming at the problem that the mutual interferences among different antennas from the desired user in the spatial multiplexing system reduce the communication quality
a new adaptive space-frequency anti-interference equalization method is proposed. Firstly
signals to be transmitted are sent to the receive antennas in the form of spatial multiplexing at the transmitter; Then
the adaptive equalizer is first designed based on the minimum mean square error(MMSE)criterion by exploiting the pilot signal received by each receive antenna; Finally
parameters estimated from the designed adaptive equalizer are used to detect the data through iterative optimization. In the proce
ss of parameter estimation
the proposed method makes use of the mutual interferences among different antennas from the desired user rather than attempts to completely remove them
thereby reducing its impact on system performance. Simulation results show that the proposed method can achieve significant gain in performance over the traditional adaptive space-time or space-frequency equalization methods. When the bit error rate is 10
-5
the proposed method achieves around 2.5 dB performance gain as compared with the existing competitors. Moreover
in the presence of interference
the proposed method also exhibits much stronger anti-interference capability compared with existing schemes
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