A Sparse Adaptive Quasi-affine Projection Blind Equalization Algorithm for Underwater Acoustic Communication
Lulu Wu, Bin Wang, Yan Huang · 2021 IEEE 21st International Conference on Communication Technology (ICCT) · 2021
A fractionally spaced dual-mode blind equalization algorithm based on quasi-affine projection (QAP) with$l_{0}$norm constraint is proposed, to improve the blind equalization performance of multiple phase shift keying (MPSK) signals in underwater acoustic (UWA) communication. Based on the conventional dual-mode affine projection algorithm (APA) and the structure of fractionally spaced equalizer (FSE), the cost function is constructed by using the$l_{0}$norm penalty on the tap coefficients of the equalizer. Then the updating formula of the tap coefficients is derived by drawing on the idea of memory improved proportionate APA (MIPAPA) and normalized factor. Simulation results show that compared with existing blind equalization, the new algorithm achieves faster convergence speed and lower residual inter-symbol interference. Besides, it also has robust adaptability and compensation capacity for deep fading sparse UWA channels, and can be flexibly applied to engineering practice.