A Dual-Band Leaky Wave Antenna With Dual-Bi-Directional Continuous Beam Scanning for Large Space Radiation Coverage

This communication presents a dual-band leaky wave antenna (LWA) with dual-bi-directional continuous beam scanning for large space radiation coverage in the C- and Ka-bands. Based on a single-layer mode composite coplanar waveguide (MCCPW) structure, a quasi-coplanar waveguide (CPW) is employed on the top layer to feed the open slots operating in the low band (LB), contributing to the horizontal bidirectional radiation of the antenna, and a substrate integrated waveguide (SIW) is introduced at the bottom of the antenna to feed the top and bottom periodic transverse dislocation slots operating in the high band (HB), contributing to the vertical bidirectional radiation of the antenna, covering eight regions scanning range in both two bands. To realize full-space beam scanning, the open stopband is suppressed by adding matching slots in the two bands and asymmetric operation in the HB, so that the continuous beam scanning from backward to forward can be obtained. By introducing slow wave structure, the scanning range is greatly expanded in LB and HB. In addition, the presented antenna is fabricated and measured for validation. Good agreement can be found between the simulated and measured results, with a peak realized gain of 11.7 dBi at 5.6 GHz and 12.8 dBi at 29.9 GHz, showing a desirable dual-band operation ability with a large frequency ratio. The scanning ranges of 180°–125° are achieved in the LB and HB, respectively.