Series- and Corner-Fed Planar Microstrip Antenna Arrays

Linear arrays along radiating (E-plane) and nonradiating (H-plane) edges are designed for broadside radiation pattern at 5.8 GHz using U-shaped series- and corner-feed configurations, respectively. U-shaped feedlines are used to reduce the interelement spacing and size of the array. A 25-element radiating edge linear array provides 19.9 dBi gain with sidelobe level (SLL) and cross polar (X-pol) level of less than -15.3 and -33.8 dB, respectively. Nonradiating edge linear array is designed up to 31 elements using the corner-feed configuration to achieve 18 dBi gain with SLL and X-pol level of less than -15.2 and -22.5 dB, respectively. Furthermore, a planar array is designed using the series and corner feeds in E-and H-planes. A 15 × 15 element array is designed to achieve 24.4 dBi gain with SLL and X-pol level of less than -14.7 and -18.8 dB, respectively, in both the Eand H-planes. This array eliminates the need of complex-, multilayer-, and lossy-feed network and improves SLL and X-pol level. A planar array of 9 × 9 elements is fabricated, and the measured results are in agreement with the simulated results.