Substrate Integrated Waveguide based Leaky Wave Antenna for Backward Scanning

Abstract

A novel substrate integrated waveguide (SIW) based leaky wave antenna (LWA) is presented for high backward endfire gain and wide range backward scanning from backward endfire to near broadside. Wide backward range, High gain, lower side lobe levels are achieved by properly designing the radiating slots, length of unit cell and width of substrate integrated waveguide. Presented design provides measured backward endfire gain of 12.1 dBi and maximum simulated gain of 20.2 dBi. Gain increases with frequency as beam begins to move away from backward endfire to near broadside providing 82 degrees of wide backward scanning range. Side lobe levels and backward lobe levels are well below -10dB. A prototype of the proposed design is fabricated. Measured results are in good agreement with simulated ones.