A modified serial-search DS code-acquisition scheme

The design of a simple and rapid synchroniser is essential for spread spectrum based communication systems. In this paper a serial-search direct-sequence (DS) acquisition scheme using a non-coherent digital sliding correlator is considered. The code acquisition scheme is modified by employing adaptive threshold detection in an attempt to target a rapid mean acquisition time. The DS acquisition scheme is simulated, and tested in the presence of additive white Gaussian noise (AWGN) and narrowband interference from which DS systems suffer most. Furthermore, the length of the digital sliding correlator is examined for best correlation length. Simulation results indicate that adaptive threshold detection is effective in improving the mean acquisition time in high and variable interference-level communication channels. It is also shown that correlation lengths of the digital sliding correlator beyond a certain length, add no significant improvement to the mean acquisition time.