Detection of Interfering Signals and Estimation of Their Carrier Frequency in CNC Satellite Communications using Cyclic Spectrum Density

Satellite communication is considered a significant part of the enemy's communication information in electronic warfare due to its unique features and widespread use in communication systems. Therefore, from the electronic support (ES) perspective, monitoring ability and identifying and analyzing enemy satellite network communication are very important. However, the new CNC technology in satellite communication has challenged the detection and analysis of the communication signal based on this technology in non-cooperative receivers, due to the nature of time-frequency overlaps. So far, no method for detecting the presence of interfering signals has been presented in open scientific literature. In this paper, the statistical cyclostationary properties of communication signals are used as a new method of detecting in-band interference in CNC satellite communication. To achieve this goal, first, the cyclic autocorrelation function for interfering signals is calculated, and mathematical equations of cyclic power spectrum density function are developed for interfering signals with less computational complexity. Then, using periodicity statistical properties of signals, in-band interference will be detected and the carrier frequencies of each interfering signal are also estimated. The results of the simulations show that the probability of correctly identifying the interference and estimating the carrier frequency in the time-frequency interference of two signals with BPSK and QPSK modulations is different. In BPSK modulation, the probability from the signal-to-noise ratio of -10dB is constant and around 98%, but in QPSK modulation, it increases from the signal-to-noise ratio of 0dB and reaches 80% in the signal-to-noise ratio of 35dB.