PERFORMANCE OF AN INCOHERENT RECEIVER FOR THE COMMAND DESTRUCT SIGNALS OF THE SPACE LIFT RANGE SYSTEM

This paper presents the performance of an i ncoherent optimal detector for detecting the presence of a known sequence of pairs of pulsed tones in the received signal. Such a tone pattern is used in the command destruct signal (CDS) employed in the United States Air Force's Space Lift Range system. T he CDS signal is sent to the launch vehicle should the range safety considerations necessitate the vehicle's destruction. The paper also shows an approximately equivalent receiver based on a FFT processor. The optimum incoherent receiver is shown to compri se of a set of correlators followed by a decision circuit. The decision circuit selects the set of frequencies corresponding to the highest two values of the correlators' outputs. If both the selected correlators' outputs exceed a specified threshold, the receiver determines that the selected tone pair is present. Otherwise the receiver determines the absence of any tone pair. The paper presents the analytical results on the probability of detection P D and probability of false alarm P F for the optimum recei ver. Finally numerical results on P D and P F are presented for a range of signal - to -noise ratio and the detector threshold.