A method for elimination of phase jitter in software signal demodulation

This paper describes a new method for phase jitter elimination. It is based on detection of signal passing through zero after demodulation, which helps to determine a residual carrier frequency, and subsequently phase jitter elimination. Classical ways of phase jitter elimination require a frequency search in some range, while this new method is much faster. The method is implemented in the software for offline analysis of modulation quality for 16-QAM signal constellation. It analyzes the signal at receiving IF of radio-relay device. The program consists of several separate functional units, which are described in text. Measurements were made on real signal under the laboratory conditions.