The TDOA Parameter Estimation About The Signals Of Frequency Hopping Radios Networking

Spread spectrum technology plays an important part in military communicationand civil communication because of its many merits such as anti-interference,anti-fading, anti-multipath, high frequency spectrum utilization rate, multiple accesscommunication and so on. It is no exaggeration to say communication technology is notcomplete without spread spectrum. Spread spectrum communication system takes theway of frequency hopping as an important way of spread spectrum. Frequency hoppingradios are easily networking and have strong flexibility. Frequency hopping radiosnetworking is essential in modern complex battlefield environment. So the armiesaround the world develop the frequency hopping communication technology at all costin order to win the control power of wireless spectrum. The sorting and ranging offrequency hopping radios networking are becoming more and more difficult as the fastdevelopment of frequency hopping technology. New algorithms about the sorting andranging of frequency hopping radios networking have appeared one by one, however,the parameter estimation method about Time Difference of Arrival is more excellentbecause of its many merits such as low cost assembling, simple device, easily concealed,high-precision passive ranging and so on. More and more researchers around the worldpay attention to this new method using TDOA parameter estimation.This dissertation mainly includes three parts. Firstly research the TDOA parameterestimation in two different transmission channel which include flat fading channel andfrequency-selective fading channel, the following is characteristic parameter estimationabout frequency hopping signal, present an improved algorithm based on Short TimeFourier Transform classical algorithm, the improved algorithm can acquire more stablecharacteristic parameter estimation comparing with classical algorithm. Secondly designa two-step clustering sorting algorithm of synchronous orthogonal and asynchronousnon-orthogonal frequency hopping radios networking signals based on the predecessors’work, the first step is the sorting of frequency hopping network taking hop duration asthe clustering center, the second step is the sorting of frequency hopping radiosnetworking signals taking radios networking characteristic parameter as clustering center, and use MATLAB simulate this designed algorithm, it is successful to sortfrequency hopping radios when the characteristic parameter estimation error is verysmall. Lastly present a new algorithm of uniting TDOA and clustering sorting toimplement the sorting of synchronous orthogonal radios networking and asynchronousnon-orthogonal radios networking. The new algorithm has little computation work andsuits for real-time processing, can effectively implement the sorting of frequencyhopping radios networking. Present a new idea for the sorting of frequency hoppingradios networking and be proved feasibly from theory.