Unified Differential Spatial Modulation

This letter proposes a unified differential spatial modulation (DSM) architecture, where a flexible rate-diversity tradeoff is achieved, while enabling a simple single-RF transmitter structure along with non-coherent detection that dispenses with channel estimation at the receiver. In our proposed scheme, by assigning a set of sparse complex-valued antenna-index matrices, only one transmit antenna element is activated during each symbol interval and then a phase-shift keying (PSK) symbol is transmitted from the activated antenna element. The explicit benefit of the proposed scheme´s universal DSM framework is ability to strike a balance between previous DSM schemes, such as the symbol-based and the block-based DSM schemes. Moreover, to attain a useful attainable diversity gain, we further extend the proposed DSM scheme in a manner that permits flexible planning of the number of symbols employed per antenna-index block.