Interchannel correlation in a bank of parallel filters

Abstract

The first-order effects of interchannel noise correlation on the fasle alarm and incorrect dismissal probabilities are computed for a bank of parallel RLC filters by expanding the envelope distribution of the n filter outputs in a power series. The correction to the false alarm probability due to noise correlation is found to decrease with increasing threshold-to-rms-noise ratios. If the filter-separation-to-filter-bandwidth ratios are larger than 0.2, it is less than 15 and 0.2 per cent for threshold-to-rms-noise ratios exceeding 12 and 14 db respectively. The correction to the incorrect dismissal probability, which is computed by considering the signal output of three contiguous filters, increases with increasing threshold-to-rms-noise and signal-to-threshold ratios. Even for filter separations larger than the filter bandwidth, it may be in excess of 100 per cent if the threshold-to-rms-noise ratio exceeds 12 db and the signal-to-threshold ratio is larger than 1.2.