The Research Of Time-Difference Measurement And Passive Multi-station Location Methods

With the rapid development of electronic countermeasure and antiradiation missile, active location system in radar system is challenged by more threat. Passive location technology, which does not radiate electromagnetic wave, can locate the radiant in a hidden way. Featuring in long function range, high anti-interference capacity, it plays more important role in improving survival and operation capacity of electronic system in the electronic war .More countries put emphasis on the research of passive location technology is receiving.TDOA Location system, namely the dual-curve location system, is a vital passive location method, which is based on the time difference of signal arrived to different stations received by there or more stations to determine the position of the target wanted to be located. It boasts of its low probability of being captured because it does not radiate electromagnetic wave. TDOA system is also featured in the capacities, such as inherent anti-interference, anti antiradiation missile, anti low-level defence and anti invisible weapons and it does not exist location hole for it does not have power overlay and clutter. It plays increasingly important role in electronic countermeasure for its advantages and survival ability. The key problem to be solved in multi stations TDOA system is spatial and time synchronism between stations, weak signal detection and solution for high precision location equation. Because the radiant signal is unknown, the problem of pulse match and signal separation becomes more complicated.Meanwhile, under the condition of continuous wave radiant ,how to get the time difference precisely in the low signal noise ratio become another problem. The paper firstly introduce basic principle of the TDOA location technology while the merits and demerits is also given. The emphasis of the research of the method of time difference measurement is how to suppress noise and interference effectively. The second part is to discuss the capacity for anti-interference of generalized cross correlation (GCC) algorithm. The algorithm based on high order cumulant is introduced to solve the problem, which is bad performance to suppress noise of GCC. The analysis is also given on the sphere of application, the complexity of computation.After the extraction of the precise TDOA signal, it is the major problem...