Research On Blind Interference Alignment Based On Reconfigurable Antenna

In wireless communication systems,inter-user interference is an important factor influencing the capacity of the system.Therefore,it is a hotspot for researchers.At present,it is in a critical period of standard setting for the 5th generation mobile communication system.Due to the higher requirements for the devices access and transmission rate,higher-rate interference management technologies will surely be used in 5G systems.Interference alignment is theoretically proved that could break the limit by the inter-user interference of system capacity,so it has attracted the attention of researchers.Traditional interference alignment requires the perfect channel state information which is difficult to obtain,thus researchers proposed blind interference alignment(BIA).BIA based on reconfigurable antenna has been widely studied.In this paper,we proposed a new blind interference alignment algorithm,based on the research of traditional blind interference alignment.The mainly content and contribution is:(1)Analyzed the DoF-oriented BIA scheme(D-BIA)and the Switch-oriented BIA scheme(S-BIA)for the mode switching problem of receivers.In D-BIA and S-BIA,as the number of users and antennas increase,the mode switching of receivers is more unbalanced.This paper takes a two-user system as an example to analyze the super-symbol of S-BIA,thus find a way to improve it.(2)Proposed a blind interference alignment scheme for two-user systems,which is balance of mode switching at receivers.Moreover,it has the same DoF of former schemes.Theoretical analysis proves that the total number of antenna switching times at the receiving end of the B-BIA is within two times of the S-BIA scheme.In addition,we took a three-user system as an example to analyze the multi-user expansion feasibility of B-BIA and provide an idea of it.