Implementation of Improved Design of Costas Carrier Recovery Loop for Coherent Demodulation

Abstract

In autonomous radio, receivers contain carrier synchronization structure that is capable of tracking carrier phase and frequency information independently. In this paper, that configuration is presented using improved design of Costas loop consists of Hilbert filter and negative feedback path for carrier regeneration. Costas loop is a closed loop scheme that successfully track fully suppressed carrier signals. The objective of this paper is to evaluate the performance of improved design of Costas loop. A mathematical modeling was developed for Costas loop presented in this paper and evaluated by using MATLAB and then implemented using SIMULINK for AM (Amplitude modulation) and BPSK (Binary Phase Shift keying) signals. The loop remove phase offsets completely and frequency offsets up to 3080 Hz.