Performance of a microstrip planar array antenna at millimeter wave frequencies using a series-parallel feed network

The authors report the simulation and measurement results of a Ka-band 4x4 microstrip subarray antenna using a novel series-parallel microstrip line feed network consisting of only 100 /spl Omega/ microstrip feed lines and without any physical quarter wave transformers. The effect of different feed impedances on the array impedance matching and gain characteristics are presented. Finally, using the proposed 4x4 subarray and the conventional corporate feed network, a 16x16 array was fabricated and experimentally tested. The array is suitable for LMCS/LMDS (Local Multipoint Communication Systems/Local Multipoint Distribution Service) applications. The basic requirements for these antennas are linear polarization, almost 30 dBi gain, and frequency bandwidth from 26.5 GHz to 29.5 GHz. The simulation results are generated using the ENSEMBLE 6.0 commercial software.