Pseudo-noise (PN) sequences are generated using linear feedback shift registers (LFSR) or nonlinear feedback shift registers (NLFSR). These sequences can be reconstructed from a short segment of the code or a longer segment for the nonlinear case. Using one of the techniques of computer generated uniform random variables a random code (RC) can be generated with the properties of well behaved autocorrelation and a fairly small cross-correlation that are needed to spread the signal at the transmitter and despread it at the receiver. Computer simulations using LabVIEW show that the generated codes have the desired autocorrelation and cross-correlation required for direct-sequence spread-spectrum (DS-SS) communication and are difficult to reconstruct from any segment of the code.
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