Dynamic sidelobe multiplexing in beamspace MIMO systems

Abstract

Recent studies on multiplexing concept over beamspace multiple-input-multiple-output (MIMO) can reduce the need for using phase shifters while keeping the directivity performance at similar levels. Thus, beamspace MIMO provides cost-effective and simple hardware designs for millimeter-wave (mmWave) systems. However, the number of users/streams that can be supported at the same time-frequency resource is limited to the number of radio-frequency (RF) chains. In this letter, to overcome this restriction, dynamic sidelobe multiplexing (DSM) algorithm is proposed. The proposed multiplexing technique precodes the transmitted data over transmitter beams in order to open up a new path to the receiver. Therefore, the proposed method provides an opportunity to exceed the limits of conventional hardware usage in beamspace MIMO. The numerical results show that the proposed approach enhance the system performance for more than 50% compared to conventional beamspace MIMO techniques.