Composite right/left-handed substrate integrated waveguide leaky-wave sparse array antenna with low sidelobe level

Abstract

As the frequency response of the CRLH antenna array is sensitive to parameters of every unit cell, changing parameters of each element to realize a tapered distribution array and low sidelobe level (SLL) performance will be difficult. In this paper, sparse array synthesis theory is applied to optimize composite right/left handed (CRLH) substrate integrated waveguide (SIW) leaky-wave antenna (LWA) to achieve low SLL. With the sparse array synthesis method, the low SLL can be achieved without amplitude and phase weighted. And all antenna elements are all the same except cell spacing. A 15-unit-cell CRLH SIW leaky-wave sparse array antenna in KU-band with low SLL is designed and simulated as an example. The SLLs are approximately −15dB in the left handed region while below −16dB in the right handed region corresponding to the scanning angle from −3.6° to 7.6°.