HYBRID PRE-CODING TECHNOLOGY IN MM-WAVE MIMO SYSTEMS

Abstract

Millimeter wave (mm-wave) MIMO system using hybrid pre-coding is one of the promising technologies for improvement in the channel capacity. The ever growing tra c exploration in cellular communication has recently drawn increased attention to a large amount of underutilized spectrum in the millimeter-wave frequency bands as a potentially visible solution for achieving tens of thousand times more capacity compared to current 4G cellular bands. There are several alternating minimization techniques which can be used to ex- plore the underutilized band. Hybrid pre-coding is one of the promising technique which can best utilize the underutilized band. Hybrid pre-coding has advantages such as lower complexity and lower cost over its completely analog or digital counter parts. However, there is a need to ascertain an optimum number of RF branches to allow for highest channel e ciency with minimum implementation complexity. This works represent the theoretical guarantee for alternate minimization using hybrid pre-coding for any variety of phase retrieval problems. The use of the well known least square algorithm to the PE-AltMin and extract the phase of the analog pre-coder and alternatively optimize the digital and analog pre-coder, which signi - cantly improves the performance of the system. Finally, the recent from the proposed algorithm attesting the practicability of the mm-wave bands for cellular usage with an acceptable amount of complexity and improvement in the performance.