Research On Cylindrical Conformal Substrate Integrated Waveguide Circumferential Slot Array Antennas

Waveguide slot antennas are widely used as an important form of antennas, particularly thanks to the excellences such as compact, thin, high gain, low side lobe, high reliability and good environmental adaptability high utilization of the caliber surface. Substrate Integrated Waveguide(SIW) slot antennas also have their own advantages such as simple process, high yield, high precision, low cost, performance, consistency, and easily conformal, etc., besides maintaining the traditional waveguide slot antenna’s advantages, so SIW slot antennas are especially suitable for communications, radar and other areas, because of which the research on conformal cylindrical SIW slot antennas is very important in engineering application area.The object researched in this paper is conformal cylindrical SIW circumferential slot antennas, mainly around the single slot characteristic, equation of array design, array design and simulation, and the influence of dielectric-covered.The background of this paper is described at the beginning. And then a brief developing history of waveguide slot antennas, SIW and conformal cylindrical antennas is introduced, and followed by the arrangement of this paper.Secondly, the comparison of propagation constant and electric field between cylindrical conformal SIW and waveguide filled with dielectric is made, which proves the equivalent relationship between SIW and waveguide filled with dielectric. After giving a brief introduction on FDTD, the circumferential slot’s characteristic curves are obtained by using FDTD. A comparison with the result of HFSS simulation software is given to verify the validity of the results.And then, the Elliott’s planar array design method is extended to the cylindrical situation and the cylindrical conformal waveguide slot antennas design equations are yielded by the rigorous mathematical calculation.Furthermore, the second design equation is modified considering the internal higher order mode coupling in waveguide. A 1×6 antenna and a 6×6 array antenna are design according to the design process mentioned above. In addition, the result of HFSS is given.The influence of dielectric-covered on the characteristics of cylindrical conformal circumferential slot and the performance of array antenna is also considered at last.