Analysis and Design of Reflectarray Antennas Based on Delay Lines: A Filter Perspective

Journal re
IEEE Access
  • Volumen: 8
  • Fecha: 01 January 2020
  • Páginas: 44947-44956
  • ISSN: 21693536
  • Source Type: Journal
  • DOI: 10.1109/ACCESS.2020.2976643
  • Document Type: Review
  • Publisher: Institute of Electrical and Electronics Engineers Inc.
© 2013 IEEE.The analysis and design of reflectarray (RA) antennas based in delay lines is introduced for the first time from a filter perspective. To this purpose, each unit-cell of the RA is considered as a network composed of two ports, one being the delay line and the other one the free-space. This approach allows to borrow the coupling matrix formalism from filter theory and apply it to design unit-cells exhibiting broadband operation together with very sharp frequency responses. The concept is demonstrated with the aid of planar printed unit-cells coupled to substrate integrated waveguides (SIWs) through slots, a configuration that offers significant advantages to shape its frequency response while providing relatively low loss. With the aim of validation, a third order filter structure integrated in SIW-based unit-cells has been experimentally tested using the waveguide simulator technique, at a center frequency of 9 GHz. Measurements demonstrate a high-quality linear phase variation and range, and large frequency selectivity together with broadband response for the element of about 18%. The experimental results show the feasibility of this approach for the design of broadband reflectarray antennas exhibiting sharp gain responses. To illustrate the concept, a medium size reflectarray has been theoretically designed using the proposed unit cell at 9 GHz, showing a directive beam with 35.8 dB gain, sharp gain selectivity over 18 dB, and confirms the wide band operation with 20.3% bandwidth for a 3 dB gain variation.

Author keywords

    Indexed keywords

      Funding details