Highly Isolated and Miniaturized SIW Based Self-Quadplexing Antenna with Modified CSRR-Inspired Slots for S-Band Wireless Applications
Matta Venkata Pullarao,
Singam Aruna and
Kethavathu Srinivasa Naik
This paper presents a highly miniaturized self-quadplexing antenna based on a quarter-mode substrate integrated waveguide. The miniaturization of the antenna is achieved by utilizing a pair of complementary split-ring resonator-inspired slots. The quadplexing characteristics of the antenna are achieved by varying the width of the inner CSRR-shaped slot. The antenna is designed to resonate at four distinct frequencies: 2.09 GHz, 2.18 GHz, 2.26 GHz, and 2.36 GHz. It demonstrates a minimum port isolation exceeding 32.6 dB between the ports. Additionally, this self-quadplexing antenna offers frequency tunability and maintains a unidirectional radiation pattern across the designated operating frequencies. The antenna's simulated and measured gains are 5.32 dBi (5.44 dBi), 5.58 dBi (5.42 dBi), 5.41 dBi (5.15 dBi), and 5.18 dBi (5.26 dBi). The design supports independent frequency tunability through the activation of four ports, with a compact size of 0.037 λ02, where λ0 is determined at lowest resonant frequency. These features indicate the antenna's suitability for S-band applications.