Interception of the triangular FM waveform via self-convolution

This paper proposes a technique for intercepting the symmetric signals and uses the example of the widely used Triangular FM waveform as a case study, due to its importance. The interception process involves performing convolution of the received signal with itself. Due to the symmetric nature of the Triangular FM waveform, the output of this self-convolution procedure is the same as the autocorrelation function of the Triangular FM waveform with a slightly higher sidelobe pedestal due to added noise. The higher sidelobe pedestal results in incurring a small SNR loss which is the price paid for blind interception of the triangular FM waveform. Simulations in this paper demonstrate the effectiveness of the proposed technique in the presence of noise. In addition, the proposed technique is found to be immune to Doppler shift and fast fading.