A Fast Nonlinear Channel RLS Equalization Algorithm in Satellite Communication

Amplitude phase shift keying signal could easily cause nonlinear distortion and generate inter symbol interference over satellite channel. To solve the problem, Wiener equalization was applied to APSK satellite communication and a fast nonlinear channel recursive least squares (NCRLS) equalization algorithm was proposed. On the basis of traditional NCRLS algorithm, the relation between forgetting factor and step length factor was established. Furthermore, a new variable forgetting factor nonlinear channel recursive least squares algorithm (VFFNCRLS) was derived, significantly enhanced the convergence speed. The simulation results show that VFFNCRLS algorithm the algorithm can effectively correct constellation warping and spectral regrowth of the nonlinear distortion signal, and also solve the problem of memory nonlinear channel distortion over satellite communication system. Moreover, it has faster convergence speed and better stability when compared with the traditional algorithms.