Revista: IEE Electronics Letters. Vol. 39. Pp. 868-870. May 2003

Autores: J.M. Pardo, M. Burgos, J.L. Jimenez

The cyclic-stationary theory is a very useful tool for signal interception and analysis since the majority of man-made
signals exhibit cyclic-stationary properties: their statistics vary periodically with time due to the different periodic processes and processing applied to these signals (modulation, coding, multiplexing, sampling). However, practical application of these techniques is not very common due to the high computational load involved. In an electronic warfare scenario one of these periodic processes is related to the rotation of the transmitter or an interceiver antenna. The
proposed system can reveal the signal presence making use of the cyclic-spectral components that appear due to this rotation. The interceiver can estimate some of the most relevant signal parameters as well as the antenna rotation period (ARP), making it possible to discriminate between signals with the same frequency and different ARP and signals
with the same ARP but with different frequencies. The interceiver antenna can be an omnidirectional or a rotating one.
In the first case it is necessary to compute all the cyclic-frequency plane in order to estimate both the transmitter antenna ARP and the signal frequency. In the second case it is possible to restrict the analysis to the known interceiver antenna ARP in order to estimate the signal frequency.