Novel Algorithms for Weak/Low SNIR Signal Acquisition

Locata is a terrestrial position system that offers cm-level accuracies, however suffers from received interference as any other radio navigation system. This paper proposes algorithms that offer improved signal acquisition in challenging situations and evaluates the performance of these algorithms using real Locata signals. The first algorithm, appreciating the complexity involved in non-coherent acquisition of Locata signals, exploits the inherent characteristics of the Locata gating sequence and offers receiver sensitivity improvement of around 1.3 dB-Hz each time the integration duration is doubled. The second algorithm introduces the concept of assisted acquisition. It is shown that acquisition of any one signal can assist acquisition of the rest from that LocataLite allowing reduction in mean acquisition time (MAT) and computational load.