On-Board PN Ranging Acquisition Based on Threshold Comparison with Soft-Quantized Correlators

Pseudonoise (PN) regenerative ranging on-board acquisition performance is assessed in terms of the acquisition time for a given probability of acquisition at a reference signal-to-noise ratio (SNR). So far the detection of the correct ranging code phase alignment has been analyzed by a maximum likelihood (ML) estimation with no amplitude quantization at the chip matched filter output. Despite its optimality in an additive white Gaussian noise (AWGN) channel, an ML estimation finds a maximum value also when no ranging signal (i.e., noise-only) is present at the receiver input thus resulting in a false alarm (FA) detection. On the contrary a suboptimum threshold comparison estimation of the correct ranging code phase alignment can overcome such a hindrance. This work reports the on-board PN regenerative ranging acquisition performance based on threshold comparison with 3-bits soft-quantized correlators along with the relevant trade-offs with respect to the ML estimation.