Увеличение эффективности обнаружения воздушных судов на догонных курсах в импульсно-доплеровских бортовых РЛС с малой высотой полета носителя

Abstract

Problem statement. The effectiveness of solving the problem of warning about possible collisions of small aircraft or unmanned aerial vehicles intended for the development of hard-to-reach territories depends on the time of early detection of another aircraft on intersecting trajectories. As a result of the comparative analysis of radar detection methods carried out in the article, taking into account the differences in the signal-interference situation characteristic of on-board pulse−Doppler radars for targets on catch-up courses in versions "multiple input - multiple output", "with joint a posteriori processing of results" and in traditional radar with active or passive phased antenna arrays have shown that the latter have energy advantages. Therefore, for this category of pulse-Doppler radars, a method for estimating the detection range on several frames is presented, which allows you to choose the logic of operation with an increase in the detection range. Research methods. The theory of antenna arrays and the theory of radar detection for pulse-Doppler radars were actively used in the work with the specified requirements for the probabilities of correct detection, false alarm and the selected model of fluctuations of the reflected useful signal. Purpose. To substantiate the advantages of technical solutions based on a traditional technical solution with phased antenna arrays for detection on catch-up courses and to develop recommendations for finding conditions that allow to increase the detection range. Results. The simulation results are presented, showing an improvement in the conditions for radar detection in onboard pulse-Doppler radars when finding the spectrum of the reflected radar signal in the Doppler frequency range, on which the spectrum of the reflected signal from the Earth's surface is superimposed when using radar with phased antenna arrays compared with spatial processing methods in MIMO and radars with joint a posteriori processing of results. A method for calculating the detection range on several adjacent frames has been developed and it is shown that in this case a longer range is achieved compared to the case of detection on a single frame. Practical significance. The results of the work can be used in small-sized onboard pulse radars of low-altitude carriers in order to increase the time of early warning of the presence of other aircraft on the flight path. This task seems to be especially relevant when flying radar carriers in hard-to-reach, developed territories.