New M-ary orthogonal spread spectrum system and its FPGA implementation
Ying Zhou · Systems engineering and electronics · 2005
An M-ary orthogonal spread spectrum system adopting a new composite PN code is proposed. This composite PN code preserves the synchronous orthogonality of walsh code. Besides, its asynchronous correlation is fine. Because of the inherent likeness of composite code the correlation between input signal and several local composite PN codes is pertormed by means of a matched filter. By virtue of this, FPGA resources consumed decrease. Finally, the results of experiment indicate that the system has lower BER than a DSSS with the same spread gain.