Accession Number : AD0716745

Title :   Doppler Shift Considerations in Naval Satellite Communication Systems Exploying Synchronous Satellites.

Descriptive Note : Interim rept.,

Corporate Author : NAVAL RESEARCH LAB WASHINGTON D C

Personal Author(s) : Leavitt,W. E. ; LeFande,R. A.

Report Date : 03 DEC 1970

Pagination or Media Count : 52

Abstract : Possible doppler shifts due to motions of existing 'stationary' satellites are shown to be as large as 212 Hz/GHz. When the contribution due to ships motion and headway are added, total shifts of 2.5 kHz at X band are possible. To avoid a severe penalty in synchronization acquisition time in operating pseudonoise or frequency hop modems now considered for Naval satellite communication, some type of automatic doppler shift compensation is required. Several compensation methods are described that cannot obtain exact correction without undue complexity but can reduce the compensation error to less than 24 Hz/kHz of beacon carrier doppler shift with relatively simple techniques. Problems of phase noise due to phase lock loop bandwidths required to track changes in doppler shift and local oscillator spectral purity remain as prime problem areas. (Author)

Descriptors :   (*COMMUNICATION SATELLITES(ACTIVE), DOPPLER EFFECT), NAVY, SYNCHRONOUS SATELLITES, FREQUENCY SHIFT, CORRECTIONS, SPACE COMMUNICATIONS

Subject Categories : Radio Communications

Distribution Statement : APPROVED FOR PUBLIC RELEASE