Performance of Serial, Matched-Filter Packet Acquisition Algorithms with a Preamble-Sequence Acceptance Criterion

In this thesis, we consider two methods to improve the acquisition performance of a packet radio system that uses serial, matched-filter acquisition: an adaptive acquisition threshold, and an acceptance criterion for the system\u27s preamble sequences. Each packet transmission includes a fixed-length acquisition preamble, and the preamble sequence used in packet transmissions is changed at predetermined times based on a sequence-generation algorithm. It is shown that acquisition performance depends largely on the sidelobe energy of the preamble sequence, the acquisition threshold, and the signal-to-noise ratio. The first method uses a threshold-scaling technique to account for the variation in the signal-to-noise ratio. The second method employs preamble sequence-selection based on the preamble\u27s sidelobe energy to reject sequences which are predicted to yield poor acquisition performance. The two techniques are considered individually and in combination, and the range of system parameters for which each is beneficial is investigated. Performance is examined for an additive white Gaussian noise channel and a signal-to-noise ratio that is unknown a priori at the receiver