English

Antenna bandwidth engineering through time-varying resistance

Applied Physics 2023-05-10 v1

Abstract

Operational bandwidth of resonant circuits is limited by the resonator's size, which is known as the Chu limit. This limit restricts miniaturization of antennas, as the antenna bandwidth is inversely proportional to its size. Here, we propose slow time modulation of resistive elements to engineer bandwidth of small antennas. The temporal modulation of resistance induces virtual impedance that is fully controlled by the modulation parameters. We show how the virtual impedance can be used to optimize the frequency response of a resonant circuit, leading to enhanced matching at multiple frequencies simultaneously. We experimentally verify the proposed technique, demonstrating enhancement of radiation of a broadband modulated signal radiated by a small antenna.

Cite

@article{arxiv.2211.06171,
  title  = {Antenna bandwidth engineering through time-varying resistance},
  author = {M. H. Mostafa and N. Ha-Van and P. Jayathurathnage and X. Wang and G. Ptitcyn and S. A. Tretyakov},
  journal= {arXiv preprint arXiv:2211.06171},
  year   = {2023}
}

Comments

6 pages, 5 figures, submitted journal letter

R2 v1 2026-06-28T05:40:12.577Z