^{A Novel Differential Phase Shift Keying With Non‐Differential Demodulation}

ABSTRACT

Differential phase shift keying (DPSK) is widely used in optical communication. The demodulation (phase‐to‐ amplitude conversion) of traditional DPSK based on one‐bit delay interference will produce a differential result of the origin data. An inverse differential operation is required to recover the origin data, which increases operation complexity, cost and delay. In this paper, a novel DPSK with non‐differential demodulation (DPSK‐NDD) is proposed. In DPSK‐NDD, the signal for modulation is in return‐to‐zero (RZ) format and the demodulation is based on half‐bit delay interference. The demodulated ASK signal is the modulated signal directly. Inverse differential operation is not required, so the operation complexity, cost and delay are all reduced. DPSK‐NDD could apply multi‐level phases to multiply the bit rate. A multi‐level DPSK‐NDD signal is demodulated to a multi‐level amplitude signal. The feasibility of the proposed DPSK‐NDD is verified by the simulated demonstration.