Study On Anti-interference Technology Of BEIDOU Navigation System Based On The Circular And Smooth Performance

Chinese independent researched and developed and independent operated Beidou satellite navigation system can provide global, all day, all-weather navigation and positioning services for the fields of water conservancy, fishery, Surveying and mapping, transportation and military, it has great science and technology, economic and military significance. However, due to the navigation satellite is very far away from earth, the received satellite signal is very weak and very easy to suffer the influence of man-made radio frequency interference and complex electromagnetic environment, so can not provide normal navigation services. It is vital important to research the anti-interference technology of Beidou satellite navigation system, just under such a background, the text revolves around a kind of important blind adaptive anti-interference algorithm based on the cyclic steady characteristics and carried out in-depth study for it and got some meaningful results:1. This paper put forward a kind of blind adaptive anti-pressure interference algorithm based on the satellite’s signal with a non-zero cyclic frequency. Because many anti-pressure interference still has the correlation in the zero cycle frequency result in the blind adaptive anti-pressure interference algorithm lose efficacy which based on cycle time delay, this paper analyze the principle of satellite spread spectrum communication system, put forward a kind of improved blind adaptive anti-pressure interference algorithm by using the satellite signal non-zero cyclic frequency. This algorithm through the simulation prove that can control more types of pressing interference. In addition, this article puts forward the algorithm for interference suppression in airspace and further extend to the space-time two-dimensional domain, make it restrain more number of interference under the conditions of without any increased antenna array element.2. To put forward the blind adaptive anti-interference algorithm with steady impulse noise. About the problem of performance degradation of conventional blind adaptive anti-interference algorithm under the impulsive noise environment, this article first introduced the concept of fractional lower order matrix and take advantage of its bounded characteristics under impulse noise and got the improved CROSS- SCORE algorithm. About the problem of limited performance of the algorithm under the strong impulse noise environment, this article further improved the algorithm from the perspective of the array response, and put forward the algorithm of fractional lower order CROSS- SCORE(FLO- CS), through the theoretical analysis and simulation results then shown that two proposed algorithms all can present a good performance under the environment of gaussian noise and impulse noise, and the FLO- CS algorithm performance is better than that of FLOM- CS algorithm under the strong impulse noise environment.3. To put forward a kind of anti-deception disturbance scheme based on array antenna. This article proposed a blind adaptive anti-interference algorithm has good inhibitory effect for the pressing type disturbance, but under the cheating interference environment, its effect is not satisfactory. At first, this paper puts forward the Cyclic MUSIC algorithm based on a non-zero Cyclic frequency satellite’s signal, the proposed algorithm has some advantages of high resolution, information source selectivity and the robustness under the low array element, and then combine the cheating interference with estimate value, zero constraint condition and the proposed anti-resistance interference algorithm, under the condition of the known cheating interference with estimate value, making it has the ability of inhibit the cheating interference and pressing type interference and improving the satellite gain ability.