A polarization multiplexed optical coherent modulation and demodulation method research based on VPI simulation

We described that coherent optical communication system is a new type of optical communication that using a single-frequency coherent light as the light source, the heterodyne receiving mode in the radio technology, QPSK modulation format is mostly concerned, it has a very narrow spectral width. In the condition of same symbol rate, the system capacity is twice as DPSK modulation, it can avoid various nonlinear effects effectively. The polarization multiplexing system is applied to the coherent receiver technology because POLUX is in use of two mutually perpendicular polarization states to transmit two independent signals, and compared to single polarization, we describes its advantages, In coherent demodulation, we are in use of digital signal processing methods to achieve, and in view of the simulation, we combined the technique of the QPSK and POLUX technology, In this article, we use the way of VPI simulation to realize polarization multiplexed coherent optical QPSK signal modulation and demodulation.