Adil Parvez

Ultra-wideband modified rectangular microstrip antenna

A new ultra-wideband planar microstrip antenna obtained by combining rectangular and circular shaped planar monopole patches is proposed. The optimum feed-line position is obtained individually for rectangular and circular patches by studying their surface current distributions. The rectangular and circular geometries are then merged to obtain a modified configuration. A parametric study for varying distances between the centers of the circular and rectangular patches and also for the gap between the radiating patch and the ground plane is conducted. The proposed configuration yields an optimum bandwidth of more than 8 GHz and a gain of 1 to 3 dBi over the bandwidth.

Broadband E-shaped space-fed array with stacked E-shaped microstrip antenna array feed

Broadband Spaced fed array fed using stacked configuration of E-shaped microstrip antenna fed by E-shaped microstrip antenna is proposed. The modified feeding structure in space fed array is used as in higher order arrays, peripheral patches are not equally fed using single microstrip patch. The fed 3 × 3 stacked E-shaped patch array yields an optimum gain of nearly 9 dBi with VSWR bandwidth of around 2.1 GHz. The 3 × 3 stacked array is then used as a feed element for the space fed array variations. Various spaced fed array configurations of the stacked microstrip array, like 1 × 3, 3 × 1, plus shaped and 3 × 3 arrays are studied. An optimum result is obtained in 3 × 3 space-fed array configuration showing a gain of nearly 16 dBi with bandwidth of 2.1 GHz.

Analysis of stepped half U-slot cut shorted SMSAs

Bandwidth of shorted compact Microstrip antenna has been increased by cutting modified half U-slot inside the patch. In this paper, a detailed study that highlights upon the broadband behavior in modified half U-slot cut shorted patch is presented. The modified half U-slot tunes the resonance frequency of higher order shorted TM1/4,1 mode with respect to fundamental TM1/4,0 mode to realize broadband response. The modified half U-slot also perturbs the surface current distribution at TM1/4,1 mode to give an broadside radiation pattern over the complete bandwidth. Thus the novelty of the proposed study lies in providing exact explanation for the broadband response in the slot cut shorted patch in terms of patch resonant modes, which is not available in reported literature.

Broadband slot cut S-shaped microstrip antenna

Bandwidth of compact S-shaped microstrip antenna has been increased by cutting S-shaped slot inside the patch. In this paper an analysis to study the broadband response in slot cut S-shape microstrip antenna is presented. The S-shaped slot in the patch tunes higher order TM20 mode frequency with respect to lower order TM10 mode, to realize bandwidth of more than 70 MHz (∼9%). The S-shaped slot modifies the surface current distribution at TM20 mode that gives broadside radiation pattern over complete bandwidth with peak broadside antenna gain of nearly 7.5 dBi. In the reported literature an explanation for broadband response in slot cut compact antennas in terms of their operating modes is not given. The novelty of proposed work lies providing detail explanation for working of slot cut patch antenna in terms of its resonant modes.

Circularly polarized sequentially rotated gap — coupled elliptical microstrip antennas array

In this paper a single fed elliptical microstrip antenna to realize circular polarization in 1000 MHz frequency band is proposed. It yields axial ratio bandwidth of 10 MHz (~1.2%). A sequentially rotated gap coupled configuration with a single parasitic patch along x axis is studied. Thereafter, gap coupled array along x and along y axis, i.e., a plus shaped array is studied to increase the ARBW. Also, 3×3 array is presented which provides return loss bandwidth and axial ratio bandwidth of 44MHz and 30MHz respectively with a gain of 1.5dBi for non-suspended configuration. For gain increment, suspended single elliptical microstrip antenna is proposed, which provides axial ratio bandwidth of 12 MHz and gain of 7dBi. The proposed gap coupled configurations yields broadside radiation pattern over entire bandwidth with antenna gain of more than 9dBi in their suspended variation. The proposed configuration can find applications in mobile communication environment in 1000 MHz frequency band and can also be tuned to a required frequency in the given range.

Space-fed microstrip array with proximity-fed microstrip antenna feed element

A space-fed array fed by a proximity fed microstrip antenna for a broader bandwidth is proposed. The 1 × 3, 3 × 1, plus-shaped and 3 × 3 configurations are studied. A parametric study for varying distances between the fed-patch and the array is done and the optimum results for each configuration have been presented. A bandwidth of 1.1 GHz and a gain of 14.6 dBi is obtained in 3 × 3 space fed configuration.

Dual polarized slot cut elliptical shaped microstrip antennas

This paper proposes a novel Multi-band dual polarized elliptical shaped microstrip antenna cut with square and rectangular slot. The square slot in elliptical patch degenerates patch TM11 and TM21 modes into two orthogonal modes to realize multi-band characteristics. The optimization of the input impedance at degenerated resonant modes is done by the introduction of the rectangular slot to realize optimum bandwidth of 1 to 2% in 1000 MHz frequency range. The proposed dual-polarized configuration yields broadside radiation pattern characteristics over all the resonant mode frequencies.

Broadband space-fed array with stacked microstrip array as feed element

Higher order space-fed arrays have limited gain due to unequal excitation of patches when fed by a single microstrip patch. Hence, a broadband space-fed array with a stacked microstrip array as the feed element is proposed. An array of rectangular microstrip antennas is placed on top of a co-axially fed broadband E-shaped patch antenna to realize a multi-layer stacked microstrip array. First, various configurations of the stacked microstrip array, like the 1 × 3, 3 × 1, plus shaped and 3 × 3 arrays, are studied. The 3 × 3 array yields an optimum gain of 8.25 dBi and a bandwidth of around 2.2 GHz. The 3 × 3 stacked array is then used as a feed element for a 3 × 3 space-fed array which yields a gain of 14.4 dBi and bandwidth of 2.15 GHz.

Design of rectangular Microstrip antenna backed by C - shaped defected ground plane

A novel design of rectangular Microstrip patch antenna backed by C shaped defected ground plane (DGP) is presented. First, effect of adding a slot in ground plane on fundamental mode is studied. A parametric analysis is performed by varying the slot width and changes in current distribution is observed. From this observation, approximate equations to calculate the resonant length of C shaped slot are proposed. Based on these equations, a dual band rectangular radiating patch antenna backed by C shaped defected ground plane is presented which gives dual bandwidth of 8MHz and 15MHz respectively.

Space fed ring microstrip antenna array with stacked rectangular microstrip antenna feed

Broadband Space fed design of compact square ring microstrip antennas fed by proximity fed rectangular microstrip antenna or by 3 × 3 gap-coupled array configurations of rectangular microstrip antennas, is proposed. Various space fed configurations of ring patch namely, single patch, 1 × 3 and 3 × 1 ring microstrip antennas, plus shaped and 3 × 3 spaced fed patch array configurations are studied. An optimum peak gain of nearly 16 dBi with BW of more than 2.7 GHz in 4 GHz frequency band is obtained in Spaced fed configuration of 3 × 3 ring microstrip patches.