Research And Implementation Of BOC Signal Anti-jamming Receiving Algorithm

With the development of navigation and positioning system,its user groups are expanding rapidly.And with the development of the satellite system,much more useful and improved navigation systems are creating.Navigation and positioning technology gradually permeates into each aspect of life.And based on their superiorities,binary offset carrier and its derived signals are broadly applied to various global navigation systems.However,due to the vulnerability of satellite signal itself,higher anti-jamming performance is being required.In order to prevent interference from all kinds of human or non-human activities,we must suppress interference signals in all forms against the receiver.In this paper,the anti-jamming algorithm is based on time domain and space-time domain.To suppress the suppressing interference,the paper chooses space-time adaptive filtering technology because of its fewer restrictions than frequency domain filtering and spatial filtering;to suppress the spoofing jamming,the thesis aims to improve and optimize the algorithm-by detecting and identifying signals after algorithm according to the multi-path fading,thus,we can finally separate the spoofing jamming signal and real signal.To suppress the multi-path interference,the paper uses algorithm to eliminate time delay and amplitude detection of inference and satellite signal.After comparing the power spectrum density and the correlation peak of the signal after the anti-interference algorithm,the signal can be restored.After that,we validate the anti-jamming algorithm of the BOC signal which is widely used in the current Global Navigation Satellite System(GNSS)system,and prove that it has a good anti-jamming effect for the BOC and its derived signals.In the end,the hardware designing of anti-jamming algorithm is completed in Field Programmable Gate Array(FPGA).The whole hardware module is divided into several parts.The functions and the implementing methods of each part are discussed,and the formation of the satellite signal data is imported into the hardware through software.After being calculated by hardware,the hardware exports data into software.Then we get approximate results between software and hardware treatments.Main research contents and contributions of this paper are as follows:(1)The anti-jamming algorithm under the BOC modulation system is analyzed and studied.(2)An anti-jamming algorithm for suppressing interference,spoofing jamming and multi-path interference at the same time is proposed.(3)In view of the similarity between deceptive jamming and multi-path interference,the algorithm of anti multi-path interference is improved so that it can be applied to spoofing jamming suppression.(4)The transverse and longitudinal comparisons of various BOC signals are developed,and the effect of the algorithm on different BOC signal models is summarized.(5)The anti-jamming algorithm is implemented in hardware system.