Single- and Multiple-RF Aided Non-Coherent Generalized Spatial Modulation

Motivated by the recent generalized spatial modulation (GSM)-multiple input multiple-output (MIMO) concept, in this paper we conceive a non- coherently detected GSM architecture, which is achieved with the aid of Cayley unitary differential encoding. More specifically, the proposed differentially-encoded transmitter structure enables us to eliminate any limitations imposed by pilot insertions and channel state information (CSI) estimation, while attaining the GSM scheme's increased transmission rate as well as reduced number of RF chains at the transmitter. Furthermore, we extend the proposed non-coherent GSM scheme to operate in a single-antenna transmitter structure. Our performance results reveal that a high transmission rate is achieved, while attaining reduced-RF branches and dispensing with the channel estimation at the receiver.