LHM Superstrate for High Directivity Microstrip Antenna

Abstract

High antenna directivity is generally desirable for wireless communication systems, whether terrestrial or based on satellites. Most of the solutions proposed for improvement of the directivity of microstrip patch antennas were to design array of several antennas. The particular disadvantage of this method comes from the feeding of each antenna and also from the coupling between each element. A suitable model to eliminate these two disadvantages is to use a separate superstrate structure. For this purpose a Left-Handed medium (LHM) superstrate used and presented in this study. Both the reference antenna and proposed antenna are simulated, fabricated, and tested. The simulation results show good agreement with the measurement results. It is observed that the reference antenna directivity increased by 1.72 dB with the proposed LHM superstrate according to the measurement results for 12 GHz operating frequency