New compact printed leaky-wave antenna with beam steering

A new printed compact structure constructed of six E-shaped arms arranged in three columns and two rows is proposed and demonstrated as a novel leaky-wave antenna beam steering from -30 to +15 with respect to broadside direction. This antenna covers the measured frequency bandwidth from 0.93 GHz to 3.65 GHz (approximately 119%, S₁₁ less than10 dB) and the scanned angle moves from backward to forward radiation as the frequency increases. The antenna with overall size of 19.2 mm by 15.2 mm by 1.6 mm (0.059 lambda by 0.047 lambda by 0.004 lambda, where lambda is free space wavelength at 930 MHz), is fabricated on Rogers-RT-Duroid5880 substrate (dielectric constant of 2.2, loss tangent of 0.0009, height of 1.6 mm). The maximum measured gain and efficiency are observed at broadside direction with 8 dBi gain and 90% radiation efficiency. This low-profile antenna can be flush-mounted on various structures including vehicles, cellular base stations, or mobile devices.