A frequency selection method for HF-OTH skywave radar systems

Functionality of a HF-OTH skywave radar is strongly dependent upon several factors. Firstly, the propagation channel is highly time-varying, secondly external radio noise is particularly severe and finally, the spectrum availability is limited by the national plan of frequencies. In this paper we propose a frequency selection method that maximizes the signal-to-noise ratio. The proposed method attempt to solve the aforementioned penalties by inspecting jointly the ionosphere and the external noise behaviour. The former is evaluated by means of simplified regional ionospheric models, while the latter is estimated by considering the recommendation given in ITU´s reports. A numerical simulation is used through the paper to explain the method.