Generalized Array Factor Approach to the Assessment of Discrete Tapered Nonuniform Leaky-Wave Antenna

A generalization of the array factor approach of a nonuniform leaky-wave antenna (LWA) is proposed for the modeling of discrete tapered LWAs. The demonstration is based on the Fourier transform of the illumination amplitude of an LWA and is thus quite general. This analysis approach can be helpful for design. When it is used in combination with classical taperization techniques, it provides an easy and powerful conception tool. The validity of the method is demonstrated with the Holey and the Honey LWAs. Taylor and cosine distributions were simulated and sidelobe level reduction up to -40 dB were obtained. A Holey antenna designed to work at 1.7 GHz with a cosine distribution was realized. Its radiation pattern was measured and it shows an acceptable agreement with theory and numerical simulations.