Research On Theory And Algorithm Of Blind Interference Alignment

Nowadays,with the swift growth of the number of mobile equipment,the demand for communication system has been increasing.At the same time,the interference becomes the crucial point in restricting the system capacity.Therefore,interference management is one of the research hotpots in wireless communication.This proposes two BIA schemes,which are named as Switching-oriented Blind Interference Alignment(S-BIA)scheme and Enhanced Switching-oriented Blind Interference Alignment(ES-BIA)scheme.This thesis considers the BIA implementation of K-user multiple-input single-output(MISO)interference channel(IC)without CSIT,in which each transmitter is equipped with ? 3(k = 1,...,K)antennas and each receiver has a reconfigurable antenna with preset modes.Stemmed from the existing DoF-oriented BIA(D-BIA)scheme,we propose a new BIA scheme to reduce the frequency of mode switching on the reconfigurable antennas while ensuring the same DoF as D-BIA.The proposed BIA scheme is named as switching-oriented BIA(S-BIA).Theoretical analysis shows that S-BIA needs less frequency of mode switching than D-BIA.Particularly,S-BIAoffers remarkable mode switching saving when the antenna number ? 3.we further take into account the frequency of mode switching within one supersymbol frame.Even though every receiving antenna is reconfigurable with preset multiple modes,from engineering perspective it is of practical importance for each receiving antenna to make less number of mode switching,in order to gain the benefits like less switching power consumption and less signal distortion.To this end,we propose in this paper Enhanced Switching-oriented BIA(ES-BIA)scheme,which preserves the same DoF gain as DoF-oriented BIA meanwhile offering reduced mode switching frequency.Theoretical analysis and simulation results demonstrate that,compared to D-BIA,S-BIA can gain 100/(M-1)percent of switching saving when Mk = M is odd for all transmitters.Remarkably,S-BIA offers 50% switching saving for multi-user 3×1 interference channels.