Energy efficient degree of freedom aided multi beam transmit antenna precoding for mmWave MIMO system

Millimeter-wave communication system provides the feasible solution for the bandwidth limitation present in the sub 6-GHz system. This millimeter-wave communication system requires large antenna array for transmission and needs better RF chain utilization methods. Often single beam transmission over multiple antennas are deployed for RF chain reduction and inter user interference reduction. Multi beam Multi RF transmission system despite capable of providing maximum capacity is affected by power leakage and hence experiences poor energy efficiency. A Multi Beam Transmit Antenna Precoding for Multi beam Multi RF mmWave MIMO system based on analog power splitter arrangement was proposed instead of existing large digital switching network to reduce complexity. In this Multi Beam Transmit Antenna Precoder setup four new precoding algorithms based on alamouti, hadamard, toeplitz and zero correlation sequence were proposed. Sum rate and energy efficiency of the proposed methods were derived theoretically, simulated and compared with existing methods. Computational complexity and degree of freedom were also analyzed for the proposed methods.