Wireless Communications pp 121-145 | Cite as

# Acquisition of Direct-Sequence Spread-Spectrum Signals

## Abstract

In order to successfully demodulate a digitally modulated signal, the receiver must first synchronize its oscillators and clocks to the received signal. If direct-sequence spread-spectrum modulation is used, then it is also necessary to synchronize to the code sequence that was used to produce the spectral spreading. Methods used to achieve coarse synchronization to the code sequence, also called acquisition of the code sequence, will be discussed in this chapter. Serial search methods require comparatively little hardware but can take a long time to achieve acquisition. On the other hand, parallel search methods can acquire the code sequence very quickly, but can be somewhat expensive to implement. A survey of some of these basic ideas is presented and some improvements on known methods are suggested.

## Keywords

Error Probability False Alarm Probability Sequential Probability Ratio Test Code Synchronization Deep Fade## Preview

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