A composite right/left-handed leaky-wave antenna with gap capacitors for backward to forward beam scanning

This paper presents a simple composite right/left-handed (CRLH) leaky-wave antenna (LWA) for continuous beam scanning from backward to forward direction through the boresight. The proposed CRLH LWA has the ability to scan the main beam from −40° to 40° by sweeping the operating frequency from 7.5 GHz to 10 GHz, with a boresight beam at 8.58 GHz. The peak gain of the antenna is 12.45 dBi and its 3dB gain bandwidth is 2 GHz (8 – 10 GHz).