Title :
Research on transmission method of CDMA satellite communication system based on time division duplexing
Author :
Xu, Xiaoyan ; Wu, Jianjun ; Luan, Xi ; Ren, Shubo ; Xiang, Haige
Author_Institution :
Sch. of Electron. Eng. & Comput. Sci., Peking Univ., Beijing, China
Abstract :
A noval signal transmission method of asynchronous code division multiple access (CDMA) is proposed to improve the utilization of uplink timeslots for the time division duplexing (TDD) satellite communication systems. The terminals at different positions within a beam of the satellite antenna transmit their data blocks at different moments in the uplink timeslot window according to a certain rule. The uplink guard time can be reduced to one time the maximum propagation delay difference in this beam, while the uplink guard time of two times the maximum propagation delay difference was needed for the synchronous reception case in Reference. Furthermore, two specific schemes are introduced to instantiate the proposed signal transmission method: transmission at discrete moments and transmission at continuous moments, and their multiple access interference (MAI) performances are analyzed and compared via simulation. It is shown that the performance of discrete transmission scheme is slightly better than the other one.
Keywords :
code division multiple access; satellite communication; time division multiplexing; CDMA satellite communication system; asynchronous code division multiple access; discrete transmission; maximum propagation delay difference; multiple access interference performances; satellite antenna; signal transmission method; time division duplexing satellite communication systems; uplink guard time; uplink timeslot window; uplink timeslots; Bit error rate; Delay; Downlink; Multiaccess communication; Propagation delay; Satellites; asynchronous reception; code division multiple access; multiple access interference; satellite communication; time division duplexing;
Conference_Titel :
Advanced Communication Technology (ICACT), 2011 13th International Conference on
Conference_Location :
Seoul
Print_ISBN :
978-1-4244-8830-8