Power Allocation-Aided Enhanced SM-OFDM: Closed-Form Solutions and Experimental Results

This paper aims to improve the error rate performance of the enhanced spatial modulation based orthogonal frequency division multiplexing (ESM-OFDM) system by jointly optimizing the signal constellation and the antenna power allocation (PA). We derive a closed-form expression for the optimal PA of the ESM-OFDM scheme for some practical antenna setups and then implement and verify the system by using an Universal Software Radio Peripheral (USRP) platform. Monte Carlo simulations and experimental results show the superiority of the derived optimal PA over the equal-gain case.