In the implementation of the wireless demodulator, numerous techniques exist to recover a carrier from the received signal. The selection of an appropriate recovery method depends on several conditions, among which are modulation type, acquisition time, tracking performance and the expected noise environment.

This project first presents a discussion on the fundamental question of communications systems and includes sections on the transmitter, channel, and receiver. Receiver structures are then explored, with a discussion of coherent and non-coherent carrier recovery techniques. Following the theoretical discussion, additional sections are devoted [to] the phase lock loop (PLL), a particularly prevelant and useful carrier recovery technique in wireless communications applications.

As a comparison to the theoretical model in the report, a simulation tool was developed using MATLAB development software. The simulation model combines the MATLAB script language with the Simulink block diagram editor to produce a tool that allows the user to enter PLL design parameters in response to a variety of input waveforms. Any part of the loop may be displayed as the PLL responds to excitations such as frequency steps, signal outages and noisy channel effects.

Numerous expressions are presented in the text for calculating the loop transfer function and response properties such as lock range, pull-out range, pull-in range and hold range, as well as the loop signal-to-noise ratio. Agreement between the expected results and the results generated by the MATLAB simulation model was observed, validating the loop filter transfer function and transient response calculations used in the model.