A missile-borne conformal dual-fed circular polarized microstrip antenna array is designed and fabricated, which realized omnidirectional radiation in horizontal direction. Frequencies of the antenna include GPS L1 frequency (1.575GHz) and Beidou navigation system B1 frequency (1.562GHz). Based on the HFSS simulation, the influence of conformation is analyzed on S11, axial ratio and gain of antenna array. The size of microstrip patches is changed so that the influence of conformation on antenna can be reduced. The circular polarization performance and the circular polarization gain of the antenna are also improved. The antenna array prototype is fabricated and measured. The result shows that the S11 parameter of the antenna is less than -10dB in the 1.55~1.60GHz frequency band. At the GPS L1 frequency and the Beidou B1 frequency, the maximum of horizontal omnidirectional gain is 1.73dB, 1.25dB respectively. The out-of-roundness of the radiation pattern is less than 2.5dB. The antenna has a good horizontal omnidirectional circular polarization radiation performance.
Design of a Missile-borne Conformal Microstrip Navigation Antenna
