Beam Steering Leaky-Wave Antenna based on Spoof Surface Plasmon Polaritons for W-band Applications

Integrated beam steering antennas are essential for sub-THz mobile applications. In this paper, a frequency-dependent beam steering leaky-wave antenna (LWA) based on spoof surface plasmon polaritons (S-SPPs) for W-band applications is reported. The antenna is composed of three main parts: a coplanar waveguide (CPW) feed line, a main operating section including S-SPP transmission line and pre-fractal-based parasitic patches, and a mode converter between CPW and S-SPP line. Simulated results show that the single-layer antenna achieves a bidirectional scanning range from ‒40° to +20° over 70 GHz to 110 GHz. The results show the maximum realized gain is 10.7 dB, and the gain variation of the antenna is 1.5 dB. In addition, the performance of the antenna is investigated above a PEC plane. By optimizing the location of the PEC plane underneath the antenna, around 3 dB gain improvement is achieved in the whole desired band.