Double Periodic Composite Right/Left Hand (CRLH) Substrate Integrated Waveguide (SIW) based Leaky Wave Antenna with Extended LH region

摘要

In this work, a double periodic composite right/left Hand (CRLH) leaky wave antenna is proposed to have continuous backward to forward beam-scanning with the slope of the main beam direction with respect to the frequency almost equal in the left handed (LH) and the right handed (RH) regions. This is achieved by obtaining a dispersion that has almost identical slope in the LH region as well as the RH region. An additional RH leaky wave region is also obtained as a consequence of the double periodic structure. A dispersion diagram analysis is performed to design the double periodic unit cell to have the desired characteristics. The overall size of the antenna is 5.16λ₀×0.8λ₀×0.0271λ₀. The antenna has three distinct operating regions. The first RH leaky wave region extends from 5.7 to 6.73GHz with a scanning range extending from 30° to 65°. The LH leaky wave region extends from 7.6 to 10.37GHz with a scanning range extending from -55° to 0° and a gain > 5dBi. The RH leaky wave region extends from 10.37 to 13.87GHz with a scanning range extending from 0° to 40° and a gain>8dBi. The slope of the main beam direction with respect to the frequency in the LH region and RH region are 20.37(°/GHz) and 28.57(°/GHz) respectively. The antenna exhibits consistent beam-scanning from the backward to forward direction with an extended LH region. Measurement results correlate well with the simulation results.