Fig. 2From: Evaluation of a class of NLFM radar signalsFirst difference of frequency function which is proportional to the first derivative of the typical frequency function shown in Fig. 1. The derivative has large value near the start and stop of the signal which correspond to the frequency band edges and small value at the low frequencies (from baseband perspective). Hence, as per SPP, the signal spends small time at the band edges and more time at the center frequenciesBack to article page