Reflection-Type Frequency Sweeping Antenna Using Frequency Coding Metamaterial

Metamaterials are artificial structures composed of subwavelength unit cells to control electromagnetic (EM) waves. The coding representation of metamaterial has the ability to describe the material in a digital way. Recently the concept of frequency coding metamaterials were proposed, in which the metamaterials were typically constructed by unit cells which achieves different controls of EM energy radiations with a fixed spatial coding pattern when the frequency changes. In this case, not only different phase responses of the unit cells are considered, different phase sensitivities are also required. Due to the different frequency sensitivities of unit cells, units with the same phase response at the initial frequency may have different phase responses at the higher frequency. By using units with different sensitivities, multiple predesigned functions can be realized by the frequency coding metamaterial without changing the coding sequence. Here we use frequency coding method to design a reflection-type antenna, which can realize predesigned frequency sweeping in the working spectra.