Implementation of Slotted Meander-Line Resonators for Isolation Enhancement in Microstrip Patch Antenna Arrays

A new approach to enhance the isolation in microstrip patch antenna arrays is described in this letter. The implementation of a slotted meander-line resonator (SMLR) is done by creating defect in the microstrip structure particularly designed for band-notch function. The resonator is designed to block the surface current at the resonant frequency of the two patch antennas coupled along H-plane and operating at a frequency of 4.8 GHz. The interelement isolation before and after the implementation of SMLR has been investigated. The proposed configuration provides an improvement in isolation by 16 dB (measured value) with a reduced edge-to-edge spacing of 7 mm (λo/9). The configuration has been designed, simulated, and validated experimentally.