Research On Handheld High-Precision Navigation Satellite Antennas

Global Navigation Satellite System (GNSS) has been widely used in navigation, surveying, positioning and timing. GNSS antenna has been widely researched as an important element in the GNSS receiver, and developed various types of antennas in order to apply different applications. General handheld antenna due its bandwidth narrow, gain directional poor and phase center unstable, inappropriate application on the handheld high-precision GNSS receiver.In this paper, a novel microstrip patch antenna with a cross-slot cut in the patch is proposed and studied, it overcomes the shortcomings of the a general patch antenna bandwidth narrow, but also has a small shape, low cost, ease of integration and many other advantages.Its features is in the center of the square microstrip patch of diagonal open four radiating slots, a cross-shaped, the cross slots recessed extension of the surface current path, increasing the equivalent inductance of the resonant circuit, the resonant frequency decreased significantly, so the specific frequency patch antenna size smaller; strong radiation generated by the cross-slot representing an increase of loss resistance. The results of the work mode Q value dropped a lot can greatly increase bandwidth.The research results show that, comparing with a general circularly polarized (CP) patch antenna, the novel patch antenna has two outstanding advantages, much wider band and smaller size. And applied to the design of a dual-band stacked handheld high-precision GNSS antenna, each patch of the antenna adopts uniform symmetry4-point feeds. That can improve the stability of the phase center, ensuring the precision. Good performances of Impedance Bandwidth, Axial Ratio, Gain and Phase center stability have been obtained by simulation of HFSS. Compared with a general dual-band antenna of CP, the antenna shows circularly polarized, with no layer between the stacked, and easy to manufacture, so it is promising in application.In addition, by improving antenna feed to improve the impedance bandwidth and front to back ratio. Those are important reference value for the handheld high-precision GNSS antenna design.Antenna arrays have many advantages of directional strong, high gain and beamformed, can be an effective solution to the problem of multipath and rejection interference. Based on this, this paper introduces the antenna arrays. And without considering the effects of coupling between antenna elements, several common antenna arrays of H-plane small dipole antenna pattern and beam steered of phased is analyzed in theory, and simulation using MATLAB. The regularity is studied that how beam quality of antenna array and beam steered are influenced by the way of array elements arranged and feed phase, etc. and compare beam quality and phased features of several antenna array. The results shows that (n+1) uniform circular arrays which is more compact, have a better quality beam, its azimuth and elevation are relatively easy to be adjusted, etc. So it is a preferred antenna arrays model for the future smart antenna.