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A CDMA synchronisation schemeCDMA (Code Division Multiple Access) is known to decrease inter-service interference in Satellite Communication Systems. Its performance is increased by chip quasi-synchronous operation which virtually eliminates the self-noise; however, the theory shows that the time error on the synchronization has to be kept at less than one tenth of a chip which, for 1 Mchip/sec. spreading rate, corresponds to 10(exp -7) sec. This, on the return-link, may only be achieved by means of a closed loop control system which, for mobile communication systems, has to be capable of autonomous operation. Until now some results have been reported on the feasibility of chip quasi-synchronous operation for mobile communication systems only including satellites on GEO (Geostationary Earth Orbit). In what follows, the basic principles are exposed, and results are presented showing how low chip synchronism error may be achieved by means of an autonomous control loop operating through satellites on any Earth orbit.
Document ID
Acquisition Source
Legacy CDMS
Document Type
Conference Paper
Soprano, C.
(European Space Agency. European Space Research and Technology Center ESTEC, Noordwijk, Netherlands)
Date Acquired
September 6, 2013
Publication Date
January 1, 1993
Publication Information
Publication: JPL, Proceedings of the Third International Mobile Satellite Conference (IMSC 1993)
Subject Category
Communications And Radar
Accession Number
Distribution Limits
Work of the US Gov. Public Use Permitted.
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