Title :
Timing aspects of synchronous CDMA
Author :
Van Nee, Richard D J
Author_Institution :
Delft Univ. of Technol., Netherlands
Abstract :
Two different techniques are introduced that can be used to synchronize a CDMA system for both the uplink and the downlink. The advantage of synchronous CDMA is that multi-user interference can be eliminated for the dominant path signals by employing orthogonal codes. The main difficulty of synchronous CDMA is the synchronization of the uplink. This paper discusses how this synchronization can be achieved. It is shown that conventional tracking loops have great problems in achieving the desired synchronization accuracy due to multipath tracking errors. A new tracking system, which estimates both line-of-sight and multipath parameters, is shown to give much better results
Keywords :
code division multiple access; interference suppression; land mobile radio; parameter estimation; pseudonoise codes; radio links; radiofrequency interference; spread spectrum communication; synchronisation; timing; DS-SS systems; dominant path signals; downlink; line-of-sight parameters; multi-user interference; multipath parameters; multipath tracking errors; orthogonal codes; parameter estimation; synchronous CDMA; timing; tracking loops; uplink; Base stations; Clocks; Code division multiplexing; Downlink; Interference elimination; Multiaccess communication; Propagation delay; Synchronization; Timing; Tracking loops;
Conference_Titel :
Personal, Indoor and Mobile Radio Communications, 1994. Wireless Networks - Catching the Mobile Future., 5th IEEE International Symposium on
Conference_Location :
The Hague
Print_ISBN :
90-5199-193-2
DOI :
10.1109/WNCMF.1994.529127
