| Satellite navigation system has been widely applied in the national defense and the national economy. Owing to the faint signal that arriving at the earth surface and the satellite navigation system is usually under unexpected or expected interference environment, anti-jamming technology of navigation system becomes one of the most important research fields of military communication. The most common studied anti-jamming technology is anti-jamming antenna array based on the antenna array beamformer technology, which is this paper focus on.HF communication is widely used in the military and civil fields. In HF communication, HF antenna is the key Component and has a significant impact to the communications effect, which is also studied in this paper.The research content is summarized as below:1. In this paper, spatial adaptive anti-jamming technology of satellite navigation system is introduced and a simulation model of adaptive anti-jamming algorithm is built with the help of ansys HFSS and Matlab. Various kinds of antenna array are simulated including different array radius or numbers. Anti-jamming performance of difference types of antenna array is studied and a guidance of the design of adaptive antenna array is summarized.2. Anti-jamming antenna array demands compact antenna elements. In this paper, a detailed research on the shorting load, which is a traditional and effective size reduction technique for patch antenna, is done with the help of transmission line(TL) model of patch antenna. Based on the research result, a novel design of coupled shorting strip with bandwidth enhancement is proposed and two compact circularly polarized(CP) patch antennas(single feed and dual feed configuration) loaded by the proposed shorting strip is designed for the application of E6 band of COMPASS Navigation System. Simulated and measured results shows that the proposed antenna is a good alternate choice for the compact CP patch with bandwidth enhancement.3. Besides single band antenna, a dual-band technology for shorting loaded patch is also proposed based on a novel shorting structure-dual coupled shorting loaded. Two dual-band antennas (one is for dual-band GPS application and the other is for GNSS application) are designed. Compared with other dual band compact antennas, the proposed antenna has the advantages of low cost, easy to fabricate and high radiation efficiency.4. In order to make the GNSS antenna size smaller, reconfiguration technology is utilized in shorting loaded patch antenna in this paper. The shorting strip and the coupling between the shorting strip is used as the variable inductor and the varactor diode and two reconfiguration antennas are designed respectively. Simulated and measured results shows that the GNSS antenna size can be further reduced without sacrificing the performance.5. HF antenna is also studied in this paper, broadband matching network and automatic antenna tuner is introduced in this paper. Accordance with the existing size problem of automatic antenna tuner. Different approaches are used to match and the imaginary and real part of the input impedance respectively. The size of the HF antenna match network is reduced significantly.
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