Research of a Microstrip Antenna Array Excited by a Planar Waveguide with a quasi-TEM Mode

An antenna array based on patch radiators powered by quasi-TEM wave propagating in a planar waveguide (asymmetric microstrip line) is proposed. A comparative analysis of simulation and experiment results for a 7-element antenna array made of rectangular patch emitters is presented. The experimental sample of the antenna array is designed for the 5.8 GHz frequency range. The results of calculations of the amplification factor and the width of the main beam of the directional pattern of the antenna array in the E- and H-plane for 9, 11 and 21 elements are presented. A linear dependence of the width of the directional pattern in the E-plane and the gain coefficient on the number of elements of the antenna array is observed. Thus, a simple design of the antenna array with the possibility of adjusting the main radiation characteristics by selecting the required number of elements is proposed. It is shown that the gain factor of the 7-element array is 14.7 dBi, and the 21-element array has the gain of 20.5 dBi.