Thesis (MEng)--Stellenbosch University, 2000.ENGLISH ABSTRACT: The purpose of this thesis is the description of the development of a QPSK demodulator
for the Sunsat 1 groundstation. A general overview of the functioning and requirements
of a typical QPSK demodulator system is given. Several methods or algorithms for clock
and carrier recovery are discussed. Specific attention is given to the QPSK demodulator
chipset from Philips used for the implementation of the demodulator. The digital
decoding logic used to serialize the parallel I and Q datastream is explained. Finally
measurement techniques for performance evaluation of QPSK systems are investigated.
As part of this the implementation loss of the developed QPSK demodulator is measured.AFRIKAANSE OPSOMMING: Die doelwit van hierdie tesis is om die ontwikkeling van 'n QPSK demodulator vir die
Sunsat 1 grondstasie te beskryf. 'n Algemene oorsig oor die funksionering en vereistes van
'n tipiese QPSK demodulator stelsel word gegee. Verskeie algoritmes en tegnieke vir klok
en draersein herwinning word ondersoek en bespreek. Spesifieke verwysing word telkens
gemaak na die QPSK demodulasie vlokkie paar van Philips gebruik vir die implementering
van die demodulator. Die digitale dekodering logika benodig vir die datastroom
verpakking word ondersoek en beskryf. Laastens word daar gekyk na meettegnieke en
evaluasie van QPSK demodulasie stelsels se prestasie. As deel hiervan word die implementasie
verlies van die ontwikkelde QPSK demodulator stelsel gemeet