Electronically Tunable High Gain Leaky-wave Antenna using Eighth-mode SIW

A novel electronically tunable compact high gain eighth-mode substrate integrated waveguide (EMSIW) based leaky-wave antenna in planar environment is proposed and investigated. The proposed antenna uses 1/8th mode SIW resonator incorporated with tunable delay line which help to steer the radiated beam. The beam switching is performed by changing the states of PIN diodes. Basically, by changing the bias voltage systematically, the polarity of diodes are changed accordingly which account a phase delay in the transmission line and steer the main beam at a fixed frequency. Due to the systematic placement of radiating EMSIW resonator unit cell on microstrip environment, the radiation intensity is improved which further enhances the overall gain of the antenna. Simulated results show that the proposed antenna is able to operate within frequency band of 9.5-11.5 GHz with beam scanning range of 48° and maximum gain of 13 dBi. All the experimental results show a fair agreement with the corresponding simulated data that validating the proposed approach.