A Novel Optical Orthogonal Modulation Format Based on Differential Phase-Shift Keying and Code-Shift Keying

We propose a novel orthogonal modulation format with differential phase-shift keying (DPSK) and code-shift keying (CSK) to improve transmission capacity of the optical code-based communication system. A 2-bit/symbol 10-Gb/s system with DBPSK/binary-CSK modulation is demonstrated.