Divya Singh

Analysis and design of circular slot cut corner truncated rectangular microstrip antenna

Analysis and design of broadband corner truncated rectangular microstrip antenna cut with two circular slots in 10 GHz frequency band is proposed. The truncated dimension and circular slot degenerate patch fundamental TM01 mode into two orthogonal modes to yield circular polarization over smaller range of the VSWR bandwidth. Further similar design of corner truncated and circular slots cut square microstrip antenna in 1000 MHz frequency band is presented. It yields VSWR and axial ratio bandwidth of 202 MHz (23%) and 44 MHz (~5%), respectively. The proposed work clearly explains the functioning of slot cut circular polarized patch antenna in terms of its operating modes as well as outlines the design procedure to realize similar configuration at other frequency.

Broadband Rectangular Microstrip Antennas Embedded with Pairs of Rectangular Slots

The wideband response in microstrip antenna is realized by cutting slot inside the patch. The proposed work here provides detailed study about the wideband behavior in one, two, and three pairs of slots (rectangular) cut rectangular microstrip antenna. The slots in rectangular patch tune resonance frequencies of higher order TM02, TM12, and TM22 resonant modes with respect to fundamental TM10 mode that yields wider bandwidth. The surface currents on the patch are modified in respective directions due to multiple slots that achieve broadside pattern over the VSWR bandwidth. Resonant mode explanation for wideband response was not available in the literature. For multiple slots cut patch antenna, the proposed work provides the same.

The Design of Wideband E-shape Microstrip Antennas on Varying Substrate Thickness

Slot cut patch antennas like C-shape, double C-shape, E-shape and U-slot cut designs are widely reported. Recently comparison between these designs is reported. However, that study does not provide any modal comparison for a wideband response. Also, identical patch dimensions were not considered in the comparison. In proposed work, for same patch dimensions, comparison for C-shape, double C-shape, E-shape and U-slot cut RMSA in terms of their resonant mode functioning is presented. Based on the explanation for resonating modes present in E-shape patch, resonant length formulations for modified patch modes in terms of slot and patch dimensions is proposed. The frequencies obtained using them agrees closely with simulated results. Further using proposed formulation design procedure to realize similar E-shape patch antenna at different frequencies and on varying substrate thickness is presented. This procedure yields wideband response for different slot and substrate parameters.

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.

Rectangular slot cut circular microstrip antennas

Multi-band dual polarized circular microstrip antenna cut with circular and rectangular slot is proposed. The circular slot in circular patch degenerates patch TM11 and TM21 modes into two orthogonal modes to realize multi-band characteristics. The rectangular slot helps in optimizing the input impedance at degenerated resonant modes to realize optimum bandwidth of 1 to 2% in 1000 MHz frequency range. The proposed dual-polarized configuration shows radiation in the broadside direction for all the resonant mode frequencies.

Angular cut circular microstrip antenna for multi-band dual polarized response

Analysis and design of multi-band dual polarized circular microstrip antenna with an angular cut and pair of rectangular slot in 1000 MHz frequency range is proposed. The angular cut degenerates TM11 and TM21 resonant modes of equivalent circular patch into two orthogonal modes to yield multi-band response. Further pair of rectangular slots optimizes the input impedance at degenerated resonant modes and also modifies the surface current distribution at them to realize bandwidth of 1 to 2% with broadside radiation pattern at each of the frequencies. The suspended configurations of proposed dual polarized antenna is also optimized, which gives more than 4 dBi of gain at each of the frequencies.

Ultra-wideband star shaped planar monopole antenna

A novel design of ultra-wideband star shaped printed monopole antenna is proposed. A star shaped structure is realized by combining triangular shaped planar monopole patch with its inverted configuration. A detailed parametric study of the offset placement of two triangular shaped patches with respect to the patch centroids, variation in distance between the base of composite structure and the ground plane, is presented. To further improve impedance matching composite structure is chopped at the lower vertex point and a parametric study for the offset feed positions is carried out. The proposed antenna yields an optimum bandwidth of more than 8 GHz ranging from less than 2 GHz to more than 10 GHz with a broadside co-polar gain of around 1 to 2 dBi over a complete bandwidth.

Key-shaped slot loaded circular microstrip antenna for multi-band and broadband response

A novel design and analysis of circular microstrip antenna loaded with a key-shaped slot is presented. The introduction of key-shaped slot in the microstrip patch excites the additional modes which are orthogonal to each other, thus demonstrating multi-band dual polarized antenna characteristics. Also the next higher order modes manifest the broadband antenna response. For the optimization of the input impedance at the excited patch modes, a rectangular slot is incorporated in the patch design which realizes optimum bandwidth of 1 to 2% at each of the frequencies in 1000 MHz frequency range. The proposed dual-polarized antenna configuration yields broadside radiation pattern over all the resonant patch modes.