FPGA-based QPSK Modulation And Demodulation System Design And Implementation

At present,QPSK modulation and demodulation mode is one of the widely used standard digital communications,including their areas of civilian radio communications,satellite navigation and deep-space communications.The task is to design and realize FPGA-based QPSK modulation and demodulation.First,the basic communication theory analysis and derivation,then leads to the principle of QPSK communication technology and the important derivation of the formula,which focus on the QPSK carrier synchronization and symbol synchronization,then QPSK communication system for detailed software separately by MATLAB simulation,the time domain and frequency domain simulation diagram of each module,and analyzes the impact of carrier synchronization and symbol synchronization loop filter parameters on the demodulation performance of the entire system,then design the digital logic system based on verilog hardware description language,use Modelsim co-simulation with MATLAB verification consistent with the theoretical results obtained.Finally,a complete simulation results demonstrate the successful realization of QPSK modulation and demodulation functions.Achieve initial design requirements.