Performance of Stereo Multiplexing in systems using direct detection with optimum dispersion maps

We present Stereo Multiplexing, a novel technique that permits simultaneous direct detection of two modulated optical carriers. This is accomplished by modulating the optical carriers with the difference and the sum of two signals. The linear performance of Stereo-multiplexed DQPSK signals is compared to single-carrier DQPSK and dual-carrier DQPSK. Subsequently, by means of simulations, the robustness of each format is compared after DWDM transmission of 55.5 Gb/s through 1040 km of SMF. This is done by searching the optimum dispersion map and input powers for each format and looking at the stability of the performance around the optimum. We show that the best performance and robustness is obtained by sharing the information between two carriers, and that Stereo is only 1 dB below dual-carrier NRZ-DQPSK. This small penalty can be tolerated if cost and complexity at the receiver side must be kept low.