Frequency Spectra in an Optical CPFSK Heterodyne Delay Demodulating Receiver using Manchester Coding

Abstract

In this paper exact analytical expressions of the power spectra of a Manchester coded CPFSK signal with arbitrary modulation index are derived. For the signal after delay & multiply demodulation exact analytical expressions of the power spectra with modulation index 1 are derived, and computer simulations are used to calculate these spectra for various modulation indices. Moreover, the analytically derived power spectra are verified by computer simulations. The simulation results correspond extremely well with the analytically calculated spectra. These signal spectra are important for the design and construction of the pre and post detection filters in the receiver.

Digitally generated CPFSK IF test signals including phase noise

“…5(a)). This spectrum is compared to a calculated spectrum [5] (Fig. 5(b)) and it is noticed that the calculated spectrum for m = 1 differs from the generated spectrum.…”