Designing a Wire Antenna for 2.4 GHz ISM Band Applications

Designing a Wire Antenna for 2.4 GHz ISM Band Applications

Abstract:

This work presents a free space wire antenna for the application of 2.45 GHz industrial, scientific, and medical (ISM) band applications. The designed antenna occupies 10 dB return loss bandwidth of 310 MHz (2320-2630 MHz) with VSWR less than 2 within the antenna bandwidth. The gain of the antenna over the antenna operating band is varies from 1.87-1.89. The characteristic impedance of the antenna is 51.44Ω at the operating frequency.

Introduction:

2.45 GHz ISM band frequency ranges from 2.4 GHz to 2.4835 GHz. Mobile Worldwide Interoperability for Microwave Access (Mobile WiMAX) or Fixed WiMAX operating bands are 2.3 GHz (2.3-2.4 GHz), 2.5 GHz (2.5-2.7 GHz), Wireless Local Area Network (WLAN) operating frequency range is 2.4-2.4835 GHz. On the other hand, Bluetooth operating frequency range is 2.4-2.4835 GHz.

   This band widely used for electronic news gathering and outside broadcast TV links in IEEE 802.11 ISM band. The designed antenna is a wire antenna of U shape. The radiation pattern of this antenna is suitable for electronic news gathering and outside broadcast TV links applications. Electronic news gathering and outside broadcast TV links are used across the UK to provide services ancillary to broadcasting. Most links tend to be used for comparatively short periods of time (hours), though some outside broadcast (OB) events may last for weeks. Within Uk there exists 15 channels of nominal bandwidth allocated for use temporary vedio links in the2390-2690Mhz band. Nine of these channels are used for ENG in London. In outside broadcasting such as formula 1 racing poleman camera is fixed point2.5Ghz. Pressure on the 2.4Ghz band from ENG/OB application will be farther exacerbated by the fact that total bandwidth available to satisfy user demand is likely to be reduced. Most specifically, the decision at WRC 2000 to allocate 2520-2670 MHz as future expansion spectrum for third generation mobile services is likely to intensify pressure on the 2390-2520 MHz band.

antenna structure

Simulation Results:

From the curve it is shown that the vswr of antenna is less than 2 from 2320-2630MHz range. At the operating frequency vswr is 1.05The shown the 10db bandwidth for a range 2320-2630 MHz  The maximum value of it is -35db and in the operating frequency it is -31.069db.In this curve the forward gain varies from 1.870-1.890 over the range. At the operating frequency the forward gain is 1.88.From the impedance curve it is shown that the characteristic impedance of the antenna varies from 45.05Ω-59.68Ω over the range. At the resonance frequency it is 51.44Ω. It is slightly high value from the standard value.

simulation result

simulation result

Experimental result:

experimental result

Course Title: Antenna Engineering LaboratoryCourse No: ECE-3208 Date of Submission: 22-02-11

Submitted by:A. F. M. Nokib Uddin Roll: 0709016 3rd Year 2nd Term Dept. of ECE, KUET