Multilayered Composite Right/Left-Handed Leaky-Wave Antenna With Consistent Gain

A multilayered composite right/left-handed (CRLH) based leaky-wave antenna is proposed for the continuous beam scanning from backward to forward direction with consistent gain. The antenna comprises a substrate integrated waveguide (SIW) with an array of the CRLH unit cells. The CRLH unit cell is formed by a slot cut on the upper ground of the SIW, and a parasitic patch beneath the slot. The antenna achieves continuous beam scanning against frequency and the optimal boresight gain at the balanced condition frequency. The antenna prototype with 15 unit cells exhibits the measured beam scanning angle of -66° to 78° over the frequency range from 8.0 to 13.0 GHz with a consistent gain of more than 9.0 dBi.