Frequency Agile, One Stage Upconverter for Single-Channel SCPC Satellite Earth Stations

Abstract

Various parameters of a phase-locked upconverter for a digital SCPC satellite terminal application have been investigated. Voice tests, BER tests and spectral measurements, using constant envelope QPSK modulation have been carried out. It is shown that constant envelope modulation has ideal characteristics for this type of upconverter. A spurious mode-locking mechanism has also been investigated and a means of preventing it has been devised and tested.