Coherent Versus Non-Coherent Reconfigurable Antenna Aided Virtual MIMO Systems

In this letter, motivated by the recent universal encoding concept of space-time shift keying (STSK), we propose a novel single radio-frequency (RF) based virtual multiple-input multiple-output (VMIMO) architecture, employing a pattern reconfigurable antenna at a transmitter. More specifically, the proposed scheme is based on the concept of pattern-time dispersion matrix activation, which is capable of striking a flexible balance between the transmission rate and the diversity gain, while enabling symbol-based low-complexity detection. Furthermore, we conceive its non-coherently detected counterpart in order to dispense with any channel estimation as well as additional pilot overhead, hence having the potential of outperforming the conventional coherently-detected VMIMO schemes in many practical scenarios.