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Around the JTIDS signal Passive TDOA location , combined with the the JTIDS signal characteristics and application environments , time delay estimation method based on TDOA location , position resolution of two key technologies were studied , focused on topics applicable to the requirements that the calculated amount small, easy to project implementation delay estimation method and positioning solution method . Finally, according to the selected method , given the program design and precision of the positioning system . Specific job done as follows: 1 , analysis of several time-delay estimation method based on the cross-correlation signal : directly related to the broad cross-correlation , cyclic spectrum method , higher-order spectrum and LMS adaptive time delay estimation algorithm , the algorithm estimated performance simulation analysis , the results showed that : the time difference estimation accuracy of such methods , but computationally intensive , complex project realization . 2 for the the JTIDS signal pulse characteristics , focus on time-delay estimation method based on signal detection . Detection portion of the text for the class of methods given three algorithms : the maximum correlation method, the autocorrelation method and higher order cumulants principle of derivation and simulation analysis , the results showed that : time delay estimation method based on the auto-correlation detection can meet system timing differences estimation of the accuracy requirements, and the calculation is simple , low complexity engineering . 3, analysis of the key factors that affect the time difference positioning accuracy obtained under different error conditions , the number of different positioning of the base station and different cloth Station positioning accuracy GDOP maps , cloth Positioning System station has a guiding role . Then , according to the system application environment for location- solver , hyperbolic asymptote least squares positioning method ( HA - LS ) . Simulation results show that : compared with the traditional algorithm , the method in the short baseline positioning environment can lead to better positioning performance , and simple . 4, completed the JTIDS signal Passive TDOA positioning system design , in the simulated environment of a given precision analysis to verify the feasibility and effectiveness of the system . Finally, a summary of the work done in this article , make prospects and future research directions .
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