On the design of cylindrical conformal microstrip antenna arrays

Summary form only given. Conformal antenna arrays are well suited to radar and communication applications. A cylindrical microstrip antenna array due to the lightweight, low-profile, low cost, integrability with microwave circuitry and simple manufacturing is an attractive choice among other systems. In order to analyze and eventually exploit such geometries, suitable modeling tools, other than the ones used for planar arrays, are needed. These tools must be able to synthesize the array and analyze the whole system, including mutual coupling. In this study we focus our effort in developing a stable and computationally effective tool that takes into account the coupling between the element radiators. Such an effort has to cope with the evaluation of Sommerfeld-type integrals and the Bessel-type Green's function. The patch antenna modeling is treated by using the surface-current model. The key assumption is that the patch metalization is replaced by a surface electric current density, which is unknown and needs to be found. The Green's function of the coated cylindrical conductor is expressed as an infinite sum of Bessel functions. The mutual coupling is found by combining method of moments with the reaction theorem for the near zone EM field of the patches. The far field is acquired via the inverse Fourier transform using the steepest decent method of integration. Mutual coupling computations as a function of frequency, of the angular separation and the cylinder radius are presented and compared with results coming from the international literature. These results show the reasonable agreement and the validation of our numerical code.