Simultaneous operation of two over-the-horizon radars

Abstract

Abstract-By exploiting the reflective and refractive nature of high-frequency (HF) radiowave propagation through the ionosphere or the conducting sea surface, over-the-horizon radar (OTHR) systems perform wide-area surveillance at long range well beyond the limit of the horizon of conventional line-of-sight (LOS) radars. Improved characterizations of the targets can be achieved by using multiple OTHRs operating simultaneously as compared to a single OTHR operating alone. In this paper, we consider concurrent operations of two OTHR systems that occupy the same frequency band with different chirp waveforms. The objective is to respond to the advanced wide-area surveillance needs without reducing the wave repetitive frequency. For this purpose, a new cross-radar interference cancellation technique is developed and its effectiveness is verified through both analytical and simulation results.

Bistatic and Stereoscopic Configurations for HF Radar

“…One must also bear in mind that potentially damaging crosstalk can occur when multiple radars in a network, perhaps stereoscopic, are obliged to share a common frequency band. In this circumstance, special signal processing is required to cancel the interfering transmissions [10]. that optimizes performance over priority areas for the specified missions.…”

“…We note that measurements from these two distinct radar designs-based on direction-finding and beam-forming, respectively-can be combined to expand network coverage and reduce down-time [7]. Skywave radar networks with overlapping coverage have been operational in Australia (JORN) [8] and the United States (ROTHR) [9] for decades; not surprisingly, there are many issues to be taken into account when designing such configurations [10,11]. The term stereoscopic has been used to describe these multi-monostatic configurations; other applications include ship target dynamic signature analysis and excitation of nonlinear scattering mechanisms.…”