Abstract:
This article proposes a compact ultra-wideband circular slot antenna (CSA) for emergency communication applications. The design utilizes the double stub matching with microstrip feeding techniques to achieve impedance matching, while the slot loading technique is employed to enhance the bandwidth of the antenna. The flexible RT/duroid 5880 dielectric material with permittivity of 2.2 is used for fabricating the proposed antenna.

Introduction:
Emergency communication systems require reliable and efficient antennas that can operate in various frequency bands. In this context, a compact ultra-wideband circular slot antenna (CSA) is proposed to meet these demands.

Design:
The proposed CSA consists of a circular shaped radiating structure constructed on top of the substrate. The double stub matching with microstrip feeding techniques are used for impedance matching, while the slot loading technique is employed to enhance the bandwidth of the antenna. The flexible RT/duroid 5880 dielectric material with permittivity of 2.2 is used for fabricating the proposed antenna.

Performance Analysis:
The performance analysis of the antenna has been carried out by using High Frequency Structure Simulator (HFSS) software. The measurement results show that the proposed circular slot antenna achieves a wider bandwidth of 4.65 GHz and maximum gain of 12 dB.

:
The proposed CSA is suitable for wearable applications and emergency communication systems due to its compact size, wide frequency band, and high radiation efficiency.

Keywords: Circular slot antenna, Enhanced bandwidth, Specific absorption rate, Wearable application

References:

1. Ansari, J. A., A. Mishra, N. P. Yadav, and P. Singh, "Dualband slot loaded circular disk patch antenna for WLAN application," International Journal of Microwave and Optical Technology, Vol. 5, No. 3, 124-129, 2010.
2. Lu, J.-H. and K.-L. Wong, "Slot-loaded, meandered rectangular microstrip antenna with compact dual frequency operation," Electronics Letters, Vol. 34, No. 11, 1048-1050, 1998.doi:10.1049/el:19980737
3. Ooi, P. C. and K. T. Selvan, "A dual-band circular slot antenna with an offset microstrip-FED line for PCS, UMTS, IMT-2000, ism, bluetooth, RFID and WLAN applications," Progress In Electromagnetics Research Letters, Vol. 16, 1-10, 2010.doi:10.2528/PIERL10051803
4. Garg, R., P. Bartia, I. Bhal, and A. Ittipiboon, Microstrip Antenna Design Handbook, Artech House, Norwood, MA, 2001.

Highlights:

• The novelty of the proposed work is the use of slot loading technique and double stub matching for achieving the wide band width of 14.36 GHz.
• Also, the flexible RT/duroid 5880 dielectric material is used for fabrication. It provides the flexibility that makes the antenna to be wearable device.

Data Availability:
No data was used for the research described in the article.