PN码 Resources

Showing items tagged with "PN码"

Pseudo-random codes, also known as PN codes, are essential sequences in spread spectrum communication. Spread spectrum communication fundamentally operates by modulating original signals with highly correlated pseudo-random sequences, causing the signal to manifest according to the sequence's characteristics. The implementation involves generating m-sequences using linear feedback shift registers (LFSRs) with specific primitive polynomials. The MATLAB code below demonstrates m-sequence generation where different polynomial configurations produce sequences of varying orders, with key parameters including tap positions and initial states determining correlation properties and sequence length.

MATLAB 337 views Tagged

A direct sequence spread spectrum communication system with interference, where PN codes are generated using m-sequence generators and transmitted through an additive white Gaussian noise (AWGN) channel. The received signal at the receiver comprises "useful signal + AWGN + interference." The system performs despreading and decision operations to recover user signals. Key implementation aspects include generating m-sequences using linear feedback shift registers (LFSRs), implementing correlation-based despreading algorithms, and employing threshold detection for signal decisions. The system demonstrates bit error rate (BER) performance versus Eb/N0 ratio under different spreading gains (10, 30, 50), showing how processing gain affects interference rejection capability.

MATLAB 259 views Tagged