A Single-Layer Periodic Leaky-Wave Antenna With Full-Space Scanning Capability

A single-layer periodic leaky-wave antenna with full-space scanning capability is presented. The antenna is made by orthogonally bent coplanar microstrip line, periodically placed coupler and stubs. Couplers are added to allow the two coplanar symmetrical microstrip line to achieve close electromagnetic coupling. As a result, the proposed antenna achieves a high scanning directivity, and higher mode disturbance is avoided. By periodically loading stubs onto the symmetrical rampart structure, the influence of fundamental mode radiation is relieved. A prototype of antenna with aperture 5.8 × 1.5 (
${\lambda }_0^2$
) is fabricated and tested. The measurement results verify that the main beam of the antenna scans continuously from −90° to 90° with peak realized gain 10.4 dBi within operating frequency band of 5.3–9.3 GHz. Gain variation range is 3.3 dBi and average efficiency reaches 85%. Compared with the traditional periodic leaky-wave antenna, the single-layer structural design of the antenna renders the ground plane and via holes unnecessary, which is very convenient for fabrication.