Title :
Fast Doppler tracking DSP-based Earth station modem for LEO satellite applications
Author :
Kandeepan, Sithamparanathan ; Reisenfeld, Sam
Abstract :
A fast Doppler (carrier frequency drift) tracking Earth station modem is presented. The modem is designed to track high carrier frequency offsets for low-Earth orbital (LEO) satellite applications. LEO satellites have very high Doppler offsets with considerable Doppler rates (rate of change of frequency). The Earth station modem tracks Doppler offsets at a data rate of 128 ksym/s for QPSK modulation. The synchronisation circuit of the modem consists of frequency synchronisation, symbol timing synchronisation and phase synchronisation. We look into the design and performance analysis of the modem, particularly the synchronisation system of the modem.
Keywords :
Doppler effect; modems; network synthesis; quadrature phase shift keying; satellite ground stations; signal processing; synchronisation; DSP-based modem; Doppler offsets; Doppler tracking modem; Earth station modem; LEO satellite applications; QPSK modulation; carrier frequency drift; frequency synchronisation; phase synchronisation; symbol timing synchronisation; Australia; Finite impulse response filter; Frequency synchronization; Low earth orbit satellites; Modems; Pulse shaping methods; Quadrature phase shift keying; Satellite ground stations; Signal processing; Transmitters;
Conference_Titel :
Intelligent Signal Processing and Communication Systems, 2004. ISPACS 2004. Proceedings of 2004 International Symposium on
Print_ISBN :
0-7803-8639-6
DOI :
10.1109/ISPACS.2004.1439070
