Low-Complexity Energy Detection for Spatial Modulation

In this paper, we present a non-coherent spatial modulation (SM) detection scheme appropriate for low-cost low-powered devices, where channel knowledge is restricted to the magnitude of the fading gains. We first derive a low-complexity energy detection metric for the multiple receive-antenna case based on the maximum-likelihood criterion. Next, we investigate a biased (non-negative) pulse amplitude modulation design and develop an accurate analytical framework for the symbol error rate at high signal-to-noise ratio. We compare the performance of the proposed scheme with that of the optimal/coherent maximum-likelihood receiver design. Numerical results show that the non-coherent SM outperforms the coherent SM technique for scenarios where non-negative one-dimensional constellations are employed.