The Design And Simulation Of Conformal Antenna For Aircraft Carrier

With the development of the information battle technology, the electronic components having smaller size, lighter weight, higher performance are preferred in the aircraft in order to improve the combat effectiveness and survivability. The conformal antenna, attached to the surface of the aircraft carriers, can save the installing space and reduce the air resistance. In this paper, a conformal microstrip antenna array and a conformal ultra wideband log periodic folded slot antenna for aircraft carriers are designed. The main contents of this paper are summarized as follows:First, a traditional microstrip antenna unit with loading parasitic patch is designed, with which a 2′2 microstrip antenna array with loading parasitic patch is designed. The simulation results show that the antenna gain array is 7.56 d B. Then the electromagnetic band gap structure(EBG) is applied to the traditional microstrip antenna unit to increase the antenna gain. Because of the band-stop characteristics of the EBG structure, it can prevent the electromagnetic wave propagation in extra frequency bands and enhance radiation gain of the antenna within specific frequency bands. Then a 2′2 microstrip antenna array using traditional microstrip antenna unit based on the EBG is simulated. The simulation results show that the antenna array gain increases 2d B than the traditional microstrip antenna array gain. Finally, a conformal microstrip antenna array is designed using traditional microstrip unit with EBG. The simulation results show that this conformal antenna array can meet the requirements of engineering application.Second, a log periodic folded slot antenna(LPFSA) fed by coplanar waveguide is designed, according to the basic principle of the log periodic dipole antenna(LPDA). The problem of impedance mismatch is solved by improving coplanar waveguide. The VSWR characteristic of the antenna in the low frequency band is improved by loading phase slot in the center conductor of the folded slot unit. The measurement of the phase slot loaded LPFSA is conducted. The experiment results show that the VSWR is less than 3.5 in the 1:9 octave bandwidth(2GHz~18GHz), which are in good agreement with the simulation results. Finally, the conformal LPFSA is designed using the phase slot loaded LPFSA. The simulation results show that the performance of the conformal LPFSA is basically tallies with the phase slot loaded LPFSA.Finally, the miniaturized LPFSA is designed based on the fractal technology. The effective electrical length of the antenna in the low frequency band is increased by using fractal technology and the fractal LPFSA is decreased by 33.3%. The test results show that VSWR is still less than 3.5 in the 2GHz~18GHz impedance bandwidth. Then, the technology of resistive loading is applied to the fractal LPFSA to improve the VSWR characteristic of the LPFSA in the low frequency band. The measured results indicate that VSWR is less than 3.5 in the 1:22.5 octave bandwidth. Finally, a miniaturized conformal LPFSA with resistive loading is investigated. The simulation results show that the VSWR of the conformal miniaturized LPFSA is slightly worse than planar miniaturized LPFSA, but the VSWR is still less than 3.5 within the whole frequency band.