Regenerative sampling self-mixing receiver: A novel concept for low complexity phase demodulation

In this paper, a novel low complexity receiver concept for high-order differential phase demodulation is introduced for the first time. With a first hardware demonstrator, a high data rate of 300 Mbit/s is achieved without requiring a synthesizer for downconversion. A phase sensitive regenerative sampling approach is employed that integrates both low noise amplifier and automatic gain control using a free running switched injection-locked oscillator with no need for stabilization by a phase locked loop. Differential phase detection is achieved by quadrature self-mixing the regenerated signal with one path delayed by the symbol period. This approach is particularly attractive in combination with the switched injection-locked oscillator due to its constant high output power that allows for matching the mixer´s best operating point. The proposed concept is demonstrated at 5.5 GHz with 8^th order differential phase shift keying and a symbol rate of 100 MBaud/s. A short range data rate of 300 Mbit/s is achieved at a bit error rate below 1e-3.