On the design of blind interference alignment using ESPAR antenna

Recently, a class of 'Blind Interference Alignment (BIA)' techniques has been proposed in [3] and [4] , which allows interference alignment to be achieved without knowledge of channel coefficients at the transmitter. In [4], the key to realizing the BIA for multi-user (MU) multiple-output-single-input (MISO) broadcast channel (BC) is the use of a receive antenna capable of switching among multiple pre-determined antenna patterns. The Electronically Steerable Parasitic Array Radiator (ESPAR) antenna, which uses only a single radio frequency (RF) front-end, has been shown to allow multiple-output-mu ltiple-input (MIMO) communication by transmitting and/ or receiving data over diverse beampatterns. As the ESPAR antenna is capable of switching antenna pattern among a set of orthogonal basis patterns, in this context, we design a MU-MISO BC where receivers are equipped with ESPAR antennas to create short-term beampattern fluctuations. We show that there are multiple potential channel values available for each user through antenna switching of an ESPAR antenna. Then, the designed system model is exploited for implementation of the BIA coding [4]. The performance of the proposed BIA scheme is evaluated via simulation. © 2012 IEEE.