Frequency-Diverse Transmission Metamaterial Aperture With a Bunching Random Beam.

In this letter, a frequency-diverse transmission metamaterial aperture (FDTMA) with a bunching random beam (BRB) is proposed for coincidence imaging. The FDTMA consists of a random modulation metamaterial lens and a broadband microstrip patch antenna array, which is used as a feed source. First, an equivalent medium containing both dielectric layer and metamaterial structure is modeled and analyzed using the electromagnetic theory. The zoom coefficients of the metamaterial elements are analyzed to simplify the design of the broadband aperture. Then, the basic metamaterial elements are designed based on the proposed model. Moreover, the FDTMA is designed using the basic metamaterial elements considering the requirements of the coincidence imaging system. Finally, the waved metal plate leveraged in the FDTMA with a BRB is optimized using the High-Frequency Structure Simulator software. The radiation patterns of the proposed FDTMA with a BRB are randomly distributed in a limited angle range in the X-band. The proposed equivalent model and the FDTMA with a BRB are validated through simulations and experiments. [ABSTRACT FROM AUTHOR]