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Analysis of the detection threshold of pulsed laser tracking systems
Žarko Barbarić
A threshold of a pulse detection is derived on the basis of three criteria: equal both false-alarm probability and missed-pulse probability, minimum probability of the total error, and constant false-alarm probability. The obtained semi-optimal, optimal and Neyman-Pearson thresholds are analyzed as a function of both signal-to-noise ratio (SNR) and gate-to-pulse duration ratio (tR/t). The number of false-alarms and the number of missed-pulses at the gate time an analyzed for all derived thresholds. The number of false-alarms is more critical than the number of missed-pulses in pulsed laser tracking systems. The number of false-alarms at the gate time is the biggest for small SNRs. But, the number of false-alarms for semi-optimal thresholds is bigger than for other thresholds for the same signal-to-noise ratio. Optimal and Neyman-Pearson thresholds are suitable when the SNR is lowr than 15 dB while for the SNR higher than 15 dB all analyzed thresholds can be used.
Key words: threshold of detection, values of threshold, false-alarm rate, missed-pulse rate.
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