Square Wave Decomposition for Fast Correlation in DSSS Receivers

Despreading is the most computationally demanding task of a direct sequence spread spectrum (DSSS) receiver. This operation can be efficiently performed by exploiting bit-wise parallel algorithms using quantized local carriers. The correlation loss due to the use of a quantized local carrier is determined, and a new class of bit-wise parallel correlation algorithms is obtained by decomposing the local carrier into a linear combination of bipolar square waves minimizing the correlation loss.