Noncoherent spectral optical CDMA system using 1-D subtracted square codes of all transmitters in one optical line terminal

We propose a family of one-dimensional subtracted square codes in the spectral amplitude coding optical code division multiple access system. The proposed codes perform the subtraction and multiplication operations to give one-to-one mappings function, which produces the code sequences of 1-D subtracted square codes. The proposed structure uses one optical line terminal to produce all of the transmitters. This proposed system overcomes the interference from other simultaneous users, known as multiuser interference, and the cross-correlations suppress the phase-induced intensity noise. In numerical simulations using the proposed 1-D subtracted square codes, we show that 83 simultaneous users can be supported at a bit error rate of 10 ^{- 9}. This number of simultaneous users in the proposed system using the 1-D subtracted square codes is superior to that in the other systems using the 1-D M sequence codes, 1-D RSQC codes, and 1-D ESP codes. The proposed system using the 1-D subtracted square codes achieves a data transmission rate of 3.2 Gbps.