Abstract:

This paper introduces a design method of M-ary orthogonal code spread spectrum system applied to high-speed data transmission. The method brings about a higher bits rate based on a primary framework or reduces greatly system sizes in the same bits rate comparing with the conventional M-ary orthogonal code spread spectrum system by combining composite sequences with M-ary orthogonal code spread spectrum technology. The performances of the system in an AWGN channel are simulated. Simulation results  show that when the structures are similar, bits transmittable efficiency improves by 17% and the antinoise capability increases by 0.1 dB at low BER.On the other hand, when 6 bits are transferred, the antinoise capability decreases by 1 dB at low BER, but the system complexity reduces by 75% as compared with the original one.