Evaluation of the noise immunity of the navigation equipment of consumers of the global navigation satellite system with spatial adaptation based on the algorithm of maintaining the level of the useful signal

Abstract

Problem statement. The use of spatial filtering of signals in adaptive antenna arrays (AAR) of consumer navigation equipment (NAP) of the global navigation satellite system (GNSS) in conditions of intentional interference is an effective means of ensuring stability and continuity of positioning of mobile objects. The specifics of solving this problem is the low level of navigation signals received from the upper hemisphere of space against the background of powerful concentrated interference, significantly exceeding noise. Most compact L-band AARs consist of 4-8 elements, and the algorithms used optimize compensation indicators without the presence of a priori information about the position of useful and interfering signals. At the same time, the formed dips on the sources of interference in width can lead to a loss of the availability of spacecraft signals for subsequent processing. This circumstance determines the relevance and practical orientation of the task of evaluating the effectiveness of the diagram formation algorithm, taking into account the integration of interference attenuation indicators and maintaining the level of the useful signal. Purpose. Investigation of the characteristics of the spatial interference compensation algorithm with a linear restriction on the direction of reception of the useful signal, as well as an assessment of its impact on the performance of the equipment of consumers of the global navigation satellite system. Results. The level of compensation of spatially distributed interference sources is analyzed using a processing algorithm that minimizes the average power of the adaptive antenna array with the exception of the direction of reception of the useful signal to the zenith. The influence of the spatial compensator on the availability of spacecraft signals for subsequent processing, depending on the number, level and angular coordinates of interference sources, is investigated. Practical significance. A model is proposed for evaluating an algorithm that maintains constant gain at the zenith and minima in the interference directions for a four-element L-band antenna array. The given values of interference attenuation depending on the number, level, angle of location and azimuth of the impact make it possible to clarify the indicators of noise immunity of the equipment of consumers of a global navigation satellite system equipped with a spatial compensator.