Research On Direction Finding And Active Counter Reconnaissance Technology Based On Uniform Circular Array

Direction-of-arrival estimation is one of the most important research directions in array signal processing.In this paper,the direction-of-arrival estimation algorithm is studied based on a uniform circular array from the reconnaissance side and the signal transmitter.The circular array has a 360-degree omnidirectional orientation Angle measurement capability,the same measurement accuracy in all directions,and the array aperture increases with radius within a certain range.These characteristics make uniform circular arrays have many advantages in array direction finding.Algorithm research is of great significance.In view of the problem that the construction method of the pseudo-covariance matrix applicable to the linear array cannot be directly applied to the uniform circular array,this paper proposes a modified pseudo-covariance matrix algorithm.By combining it with the pattern space method,the uniform circular array can be received The data is completed by single snapshot direction finding;this paper combines the pseudo-covariance matrix method of the uniform circular array with the conjugate enhancement method,and proposes the ISS-MUSIC method based on the uniform circular array,and compares these two methods with the spatial smoothing method The simulation verifies the effectiveness of the algorithm,and proves that the performance of the pseudo-covariance matrix method is superior to the spatial smoothing method,while the performance of the ISS-MUSIC method is superior to the pseudo-covariance matrix method.Aiming at the key problem in the direction measurement of uniform circular array phase interferometer-phase blur,this paper studies the extended baseline method and the parallel baseline method based on it,and simulates the direction finding performance of the interferometer using them to deblur;The comparison simulation verifies that the parallel baseline method has the same performance as the extended baseline method,and the calculation amount is much lower than the extended baseline method.Therefore,the parallel baseline method is more suitable for environments with high real-time requirements.Aiming at the need to conceal the signal source in some environments,combined with the shortcomings of the traditional direction finding algorithm,several strategies for protecting the signal source are proposed,so that the reconnaissance party estimates the source and the direction of arrival each time Different,it is difficult to make accurate judgments.These strategies include the protection strategies based on the transmission of different power signals,different snapshot numbers,alternating transmission signals,and mixed protection;the direction finding performance of the reconnaissance in the face of each strategy is under different conditions Simulations were carried out to verify the effectiveness of the protection strategies.These strategies enable the signal transmitter to effectively conduct anti-reconnaissance.