A compact composite right/left-handed (CRLH) leaky wave antenna composed of 2 × 2 coupled-mushrooms for broadband wireless communications

This paper presents a compact composite right/left-handed (CRLH) leaky wave antenna (LWA) composed of 2 × 2 coupled-mushrooms for broadband wireless communications. By optimizing gap widths between the mushrooms, the proposed antenna provides following attractive features; 1) a broadband performance from 6.4 GHz to 10.5 GHz is obtained, which fractional bandwidth corresponds to 49 %. 2) a high radiation efficiency of more than 98 % is attained through the entire operation band. 3) The radiation pattern of the antenna shows a weak directivity, which will be useful for high-speed data communications in mobile use. 4) Since the antenna has a planar structure based on a microstrip line configuration, the conventional print circuit board (PCB) facilities can be used for fabrication, leading to low cost antenna production. The overall dimension of the proposed antenna is 50 mm × 70 mm × 3.2 mm including the antenna substrate.