S. N. Mulgi

A NOVEL SLOT FOR ENHANCING THE IMPEDANCE BANDWIDTH AND GAIN OF RECTANGULAR MICROSTRIP ANTENNA

This paper reports the design and development of rectangular microstrip antenna comprising a novel slot for enhancing the impedance bandwidth and gain. By incorporating a slot of optimum geometry at suitable location on the radiating patch, the antenna provides 78.08% (3.39{7.73GHz) of impedance bandwidth and 3dB of gain without changing the nature of broadside radiation characteristics when compared to conventional rectangular microstrip antenna. The proposed antenna may flnd applications in mobile WiMax, IEEE802.11a, HIPERLAN/2, cordless phones, flxed wireless etc. Design concept of antennas is given, and experimental results are discussed.

Microstrip array antenna for multiband operation

A novel design of corporate fed four element rectangular microstrip array antenna (FRMAA) has been proposed for triple band operation at X-band frequency. By increasing the number of array elements from four to eight, the triple band operation can be converted into dual bands. This overall impedance bandwidth is 1.16 times more than the impedance bandwidth of FRMAA with improved broadside radiation characteristics. The dual-frequency patch antennas may provide an alternative to large-bandwidth planar antennas, in applications in which large bandwidth is really needed for operating at two separate transmit-receiver bands. When the two operating frequencies are far apart, a dual-frequency patch structure can be conceived to avoid the use of separate antennas. The design concept of antennas is presented and experimental results are discussed.

Aperture-coupled equilateral triangular microstrip array antennas for single and multiband operation

A novel design of aperture-coupled two-element equilateral triangular microstrip array antenna (ATEMSA) is proposed for multiband operation. A horizontal slot of optimum dimension if loaded at the center of radiating elements of ATEMSA, it converts multiband into single wideband without changing the nature of broadside radiation characteristics. The magnitude of impedance bandwidth is found to be 3.1 times more when compared to the impedance bandwidth of conventional equilateral triangular microstrip antenna (CETMSA). The gain, azimuthal radiation patterns and input impedance of proposed antennas are studied and reported. Details of the antenna design are given and experimental results are discussed.