Interferometer Passive Reconnaissance Location From Single Observer And Implementation

With the rapid development of electronic, space and radar technology, the traditional active localization equipment are confronted with serious threat of interference, spoofing and anti-radiation weapons. Passive localization can obtain the position estimation in a far-distance, high-safety and low-cost method without electromagnetic radiation. Single observer passive localization avoid time synchronization and data fusion, so it has better agility and flexibility, especially in the effective application of unmanned aerial vehicle. Single observer passive localization has been a hot research field in battlefield reconnaissance and surveillance, guided weapons and electronic warfare. In this paper, a research on interferometer single station passive reconnaissance positioning has carried out the following work:1. The acquisitions of direction of arrival are introduced, and the principle of interferometer is analyzed. A rotary interferometer direction finding is presented with the simulation results to analyze its direction finding accuracy and influence factors; A 2-dimensional 9 array element circular interferometer is proposed and uses the virtual baseline for fuzzy phase difference solutions with a least squares estimate for direction, the simulation results show its performance advantages and application conditions.2. The space geometry principle of target localization is referred, the theory, observability, condition and performance of single observer passive localization are analyzed and compared. This paper puts forward a interferometer direction finding weighted least squares of single observer passive location method, simulation examples show that it has almost identical performance for accuracy levels attainable by engineering survey technology. The phase difference and phase difference change rate of single observer passive localization in the project of this paper is mentioned and detailed simulation results are provided for its application.3. Due to nonlinear initial localization equation, relative merits of linear and nonlinear equation solution are analyzed, and then introduces the semi-definite relaxation programming technology which has a lot of recent research in areas of mathematics and signal processing. In learning the concept of the theory of this technology and application method, this paper successfully utilizing semi-definite relaxation programming method in the interferometer direction finding single observer passive location, and use simulation results to prove its superiority.4. In this paper, a method is elaborated for the hardware implementation of single observer passive reconnaissance localization. The system structure and hardware implementation are presented for interferometer single observer passive reconnaissance localization. This method adopts FPGA for high intercept probability of impulse in low SNR environment and parameter extraction, uses DSP to complete impulse signal de-interleaving and intra-pulse analysis, and then utilizes the embedded phase difference and phase difference change rate for target localization. A brief analysis is made for various parts of the system and optimization method. Finally the test results show that this system can achieve rapid, high precision target localization under complex multiple objective electromagnetic environment.