K-Band Frequency-Scanned Leaky-Wave Antenna Based on Composite Right/Left-Handed Transmission Lines

A frequency-scanned leaky-wave antenna at K-band is proposed, which is based on two composite right/left-handed (CRLH) transmission lines with a virtual ground in between and composed of two identical RT 5880 substrates. The main beam of the proposed leaky-wave antenna scans from -25
^°
to +50
^°
, i.e., from backfire to endfire, as the frequency varies from 20 to 30 GHz. The highest antenna gain reaches 14 dB at a backfire direction. The proposed antenna has no vias. Its dimensions are 155 × 34 mm
²
.