High Dynamic GPS Receiver Base Band Signal Procrssing Algorithm Research

The high dynamic receiver could still work normally when the received signal has the high Doppler frequency and in the first-order, the second time derivative。This article studies the designing and realization of the real-time high dynamic base band signal processing module according to the GPS receiver base band signal processing algorithm's problems base on the high dynamic low signal-to-noise ratio environment, . This article mainly carries on the following several research work:Weak signal capture algorithm design. The article firstly analyzes and compares four kinds of capture algorithm's characteristic, then has analyzed gain of the coherent capture algorithm and the non-coherent capture algorithm. The article has realized the input signal-to-noise ratio 25dBHz for the signal capture with coherent capture algorithm and non-coherent capture algorithm, and has provided one kind of non-coherent cumulative time design proposal.Pseudo-code track algorithm, key parameter and ring circuit control policy design. Under the high dynamic environment the Doppler effect influences the pseudo-code can not be neglected, the article analyzes Normalized belt mark dot product power pseudo-code track algorithm which matched with the high dynamic carrier track algorithm and based on the carrier auxiliary technology ,and proposed one kind of new pseudo-code track link control policy that preventive maintenance integration time is variable.Carrier track algorithm, key parameter and ring circuit control policy design. The high dynamic GPS software receiver base band signal processing algorithm's key is the carrier track algorithm design, the article studies the frequency pulling algorithm, FLL and the PLL compound link algorithm and the carrier track link's key parameter design. The article proposes one kind of new carrier track link control policy by stages, and has given dual attention to ring circuit's dynamic and accuracy.This article uses the high dynamic GPS satellite signal which the simulator simulates for the experimental subject, realizing GPS receiver base band signal processing algorithm based on MATLAB and the VC++ software platform under the high dynamic low signal-to-noise ratio, proved after the experiment, the receiver can work steadily in the carrier tendency for the maximum speed, the maximum acceleration, the most acceleration, unifies the following localization resolving module, the pointing accuracy which the receiver achieves finally reaches the horizontal direction is 10 meters, the direction is 15 meters highly, can satisfy the topic request of the pointing accuracy.