Two Stage Parallel CMA-LMS Adaptive Equalization in High Speed Satellites

In order to overcome the problem of inter-symbol interference in signal transmission caused by the effect of non-linear group delay in high speed broadband satellite transmissions, a partially parallel two-stage two-mode CMA-LMS adaptive equalization with fast convergence speed and small stable error is proposed in this paper. By the CMA and the LMS algorithm, a two-stage hybrid two mode blind-or-not frequency domain equalization is set up. In addition, a FFT based fast partially parallel filter structure is adopted to implement the nonlinear group delay equalization in high speed broadband satellite transmission channel at the cost of trivial bandwidth occupation of a small amount training words. So it improves the efficiency of the signal spectrum, which enable it rather good application value. Simulation results indicate that the proposed equalization algorithm possesses good performance of approaching ideal equalization. Furthermore, a algorithm framework of a partially parallel structure is designed and analyzed with the complexity. Therefore, it can realize frequency domain equalization of the high speed and reliable non-linear satellite channel on condition that limited resources are available for the satellite communication implementation.