Substrate Integrated Waveguide Leaky-Wave Antenna With Wide Bandwidth via Prism Coupling

New communications systems require high-speed data transfer and need high frequency, wideband, and directive antennas. Leaky-wave antennas are a desirable type of antennas for millimeter and submillimeter waves, since they can produce a high directive radiation with a single feeding. The latter is an enormous advantage to reducing the cost and losses at high frequency. Despite these advantages, their dispersive nature inherently produces a beam squint effect in their radiation patterns. Here, we propose the use of a lens that compensates for the dispersion of the leaky wave, making the overall antenna broadband. This concept is demonstrated in substrate integrated waveguide technology at Ka-band, and the lens is integrated in the same technology. Full-wave simulations and experimental results are presented to demonstrate the potential of our proposal. Our manufactured prototype has more than 20% frequency bandwidth for the 3-dB pattern at (sic) = 31 degrees, and the main radiating direction steers only +/- 0.5 degrees from 35 to 40 GHz with a half-power beamwidth of 8 degrees.