Title :
DS-CDMA for uplink low data rate transmission in multibeam satellite communications: radio capacity perfromance
Author :
Xu, Ying Lin ; Weng, J. ; LE-NGOC, THO
Author_Institution :
Dept. of ECE, McGill Univ., Montreal, Que., Canada
Abstract :
This paper presents a performance evaluation of various spreading codes applied to DS-CDMA for uplink low data rate transmission in multibeam, variable-rate, and quasisynchronous satellite communication over a LOS channel. The simulation results indicate that both PP-Gold/Long and Walsh/Long codes provide the best performance. If the timing offset for the two-level spreading scheme is smaller than a determined limit, there is no capacity loss as compared to the perfect synchronous case. Furthermore, a code reuse scheme is also given to improve the radio capacity of the system, but it requires more precise synchronization. In general, the performance of a CDMA-based satellite system is mainly limited by the interbeam interference.
Keywords :
channel capacity; code division multiple access; radio links; radiofrequency interference; satellite communication; spread spectrum communication; variable rate codes; DS-CDMA; LOS channel; Long code; Walsh code; code reuse scheme; code spreading; interbeam interference; multibeam satellite communication; offset timing; preferentially phased-Gold code; quasisynchronous satellite communication; radio capacity; spreading scheme; uplink low data rate transmission; variable-rate satellite communication; Additive white noise; Autocorrelation; Bit error rate; Gold; Interference; Multiaccess communication; Satellite antennas; Satellite broadcasting; Satellite communication; Timing;
Conference_Titel :
Electrical and Computer Engineering, 2003. IEEE CCECE 2003. Canadian Conference on
Print_ISBN :
0-7803-7781-8
DOI :
10.1109/CCECE.2003.1226194
