A New Equalizer for Non-sinusodial HF Communication Based on Prolate Spheroidal Wave Function

The multipath effects of the HF channel make the BER of non-sinusodial HF communication based on Prolate Spheroidal Wave Function (PSWF) increasing. An new equalizer scheme is proposed on the base of analysising the factors reducing the quality of decision dates and the particularity of the non-sinusodial communication systerm based on PSWF. This scheme transfer the effects of ISI to the quality of the decision date signals，and taking measures to equilibrium each path of decision date signals to improve its quality. Finally, the disicion will be made according to the judgement criterion. The results of the simulations show that the new equalizer is effective, and the BER can be reducing from 10-2 to 10-3, when the SNR is 24 dB. For the group of different characteristics of PSWF pulses which come from different pulse generating methods including constructing method of PSWF based on single-channel and constructing method of PSWF based on multi-channel, parameters shared equalizer and grouping parameters shared equalizer are put forwad. The results of the simulations show that: the two kinds of equalizers are effective.