BPSK Modulation and Demodulation Implementation

In our project, we need to implement a BPSK (Binary Phase Shift Keying) modulation and demodulation program. Although the documentation provides some explanations, we can further elaborate on the working principles of BPSK. BPSK is a digital modulation technique that uses sine waves to modulate binary data signals, generating a signal with phase information. At the receiver side, the demodulator converts this phase-modulated signal back into binary data. To implement this process correctly and stably, we need to program both modulation and demodulation functions. The modulation function typically involves mapping binary 0 and 1 to different phase states (usually 0° and 180°) of the carrier wave. For implementation, we can use mathematical operations where binary 0 is represented as +1 and binary 1 as -1, multiplied by the carrier signal. The demodulation process requires coherent detection using a phase-locked loop (PLL) to recover the carrier phase. Key functions include correlation detection where the received signal is multiplied with the reference carrier and integrated over each symbol period. Decision logic then determines the original binary data based on the sign of the correlation result. In our program design, we must consider several critical factors such as channel noise, bit rate, and baud rate. To handle channel noise, we can implement error correction coding techniques like convolutional codes or Reed-Solomon codes. For timing synchronization, we need to incorporate symbol timing recovery algorithms, such as early-late gate detection or Mueller and Müller synchronization. The program architecture should include modules for: - Data preprocessing (packetization and coding) - Carrier generation and phase modulation - Channel simulation with configurable SNR - Coherent demodulation with phase recovery - Symbol synchronization and decision making - Performance evaluation (BER calculation) We need to thoroughly analyze these factors and implement appropriate processing methods to ensure the program operates reliably under various conditions. Testing should include simulations with different noise levels, fading channels, and timing offsets to validate robustness.