A Multidimensional Signal Receiver Based on Time Interleaved Phase Diversity Detection

To adapt to the new characteristics of communication traffic distribution, a detection scheme suitable for medium-to-short-reach optical communication system is urgently needed. The receiver should have both low-complexity characteristics and the ability to obtain multi-dimensional vector information, thus building a bridge between traditional coherent detection and direct detection. In this paper, we propose a time interleaved phase diversity detection (TIPD) scheme which can realize the demodulation of multi-dimensional (amplitude, phase and polarization) vector signal based on single photodiode (PD). By utilizing the phase differences among several samples within a symbol, TIPD can eliminate the signal-signal beating interference (SSBI) and realize the optical field recovery. Moreover, exploiting the mutual independence of orthogonal polarized lights, this scheme could directly support polarization demultiplexing, which further increases the transmission capacity. The performance of the proposed scheme is analyzed detailly by simulation. Also, we experimentally demonstrated the detection of polarization multiplexed 64-Gbps 16 quadrature amplitude modulation (QAM) and 16-Gbps NRZ by a single PD, which further verified the feasibility of the proposed scheme. We believe that TIPD provides a new solution for multi-dimensional signal demodulation based on direct detection.