Abstract:

An analysis of noise immunity of the searchless digital method of correlation-interferometric direction finding with reconstruction of the spatial analytical signal has been carried out. An analytical estimate of the direction finding error variance consisting of the noise and interference components was obtained. It was shown that the main controllable factors affecting the noise component of the direction finding error variance are as follows: the number of direction-finding channels, the amount of separation between the selected elements of the antenna array, the type of the weight function in spatial spectral analysis and the time of emission analysis. The interference component of the direction finding error variance, unlike the noise component, does not depend on the analysis time but is determined, first of all, by the quality of frequency-spatial selection. In simulation, a family of dependencies of the root mean square deviation of the bearing estimate on the signal-to-noise ratio and the type of the weight function of the spectral analysis window was obtained. Possibility of direction finding with a value of the root mean square deviation of the bearing estimate of 0.03 degrees at an input signal-to-noise ratio of 0 dB has been shown. The estimates of the direction finding error variance obtained analytically and by software simulation practically coincided which confirms the analysis correctness. As a result of simulation, a family of dependences of root-mean square deviation of the bearing estimation on the separation of direction to the signal and interference sources at different signal frequencies was also obtained. It was determined that when the 64-element linear array is used, the resolution of the direction finder depends on the signal frequency. It varies between 6–15 degrees in the range of the direction finder operating frequencies at a signal/interference ratio of 0 dB. The resolution of the direction finder which was found to be high compared to the annular antenna array is an important advantage in conditions of a complex electromagnetic situation. Author Biography Vitaliy Tsyporenko, Zhytomyr State Technological University Cherniakhovskoho str., 103, Zhytomyt, Ukraine, 10005 PhD, Associate Professor Department of radio engineering, electronic devices and telecommunications

Keywords: