FPGA Implementation and Carrier Recovery Based on Costas Loop

In order to solve the frequency offset caused by the inconsistence of RF transceiver frequency, the Costas loop algorithm is used to realize carrier synchronization. On the basis of analyzing the principle of the algorithm, the feasibility of Costas loop algorithm based on arctangent in the actual transceiver environment is verified by combining MATLAB with the actual transceiver environment. In FPGA based engineering implementation, table lookup method is used to reduce the time delay of feedback loop and thus reduce the clock frequency of FPGA. Simulation and engineering verification show that the loop implemented in this work can realize carrier synchronization, provide correct data for subsequent demodulation and decoding, and realize synchronous demodulation of BPSK modulated signals.