Sudipta Chattopadhyay

Rectangular Microstrip Antenna on Slot-Type Defected Ground for Reduced Cross-Polarized Radiation

A simple rectangular microstrip antenna on slot-type defected ground plane is proposed for reduced cross-polarized (XP) radiation and justified theoretically. This will reduce the XP radiation field compared to a conventional microstrip antenna without affecting its copolarized (CP) radiation characteristics.

Rectangular Microstrip Patch on a Composite Dielectric Substrate for High-Gain Wide-Beam Radiation Patterns

A rectangular microstrip patch on a composite substrate is theoretically and experimentally investigated. Considerably wide radiation beamwidth along with high gain is experimentally demonstrated. Compared to a conventional microstrip patch, the proposed configuration shows as much as 75% increment in beam width in its H-plane and nearly 10% in E-plane, indicating the peak gain of the order of 8 dBi.

Physical and Quantitative Analysis of Compact Rectangular Microstrip Antenna with Shorted Non-Radiating Edges for Reduced Cross-Polarized Radiation Using Modifi ed Cavity Model

A straightforward and compact rectangular microstrip antenna with a shorted nonradiating edge was proposed and experimentally investigated for significant suppression of cross-polarized (XP) radiation compared to maximum co-polarized gain, without affecting the co-polarized radiation pattern. The proposed antenna was thoroughly studied using simulation and experimental results. A modified cavity model (MCM) was also demonstrated to understand the behavior of the cross-polarized radiation and the complete resonance behavior for the new structure. The proposed theory helps to germinate a real and clear view of the observed phenomena. The proposed idea was experimentally confirmed with the present structure on three different substrate materials, with different dielectric constants. The new approach presented here provides an insightful visualization-based understanding of cross-polarized suppression with the present structure.

Improved Cross-Polarized Radiation and Wide Impedance Bandwidth From Rectangular Microstrip Antenna With Dumbbell-Shaped Defected Patch Surface

Rectangular patch with dumbbell-shaped defected patch surface has been studied theoretically and experimentally to improve polarization purity over wide angular range and broad impedance bandwidth. More than 30 dB co- to cross-polarization (CP-XP) ratio over entire angular range around the broadside direction with wide impedance bandwidth is obtained. Moreover, the present structure is free from back radiation in terms of XP fields, and it can efficiently suppress the XP radiation in different diagonal planes. The present structure is very simple and easy to manufacture. The present investigation provides an insightful visualization-based understanding of concurrent improvement in impedance bandwidth and the XP radiation characteristics with the present structure.

Radiation characteristics of rectangular patch antenna using air substrates

A rectangular microstrip patch on air substrate is theoretically and experimentally demonstrated and compared with conventional microstrip patch. Compared to conventional one, these show improved radiation performance. Around 2–3 dB improvement of peak gain observed.

Improved Cross Polarization and Broad Impedance Bandwidth from Simple Single Element Shorted Rectangular Microstrip Patch: Theory and Experiment

Abstract A simple, compact and single element rectangular microstrip antenna with three pairs of shorting plates has been proposed and investigated experimentally for broad impedance bandwidth and improved cross polarized (XP) radiation compared to maximum co-polarized (CO) gain without affecting the co-polarized radiation pattern. Around 25–40 dB isolation between copolarized radiation to cross polarized radiation (CO-XP isolation) along with 1.32 GHz impedance bandwidth is achieved with the proposed structure. The present structure is very simple and easy to manufacture and provides high CO-XP isolation over entire angular range around the broadside direction. Moreover, the present structure is free from back radiation in terms of XP fields. The present investigation provides an insightful, visualization-based understanding of concurrent improvement in impedance bandwidth and the XP radiation characteristics with the present structure.

Rectangular microstrip antenna with defected patch surface for improved polarization purity

A simple and compact rectangular microstrip antenna with circular arc defected patch surface is proposed for significant suppression of cross polarized (XP) radiation and improved polarization purity. The proposed antenna has been studied methodically with theoretical justifications. Simulation and experimental results are also presented in support of the present idea. The proposed structure is simple and easy to fabricate. Around 25 dB of XP radiation isolation from co polarized (CP) radiation is revealed. The effect of dimensions of the defect on the radiation performance of the proposed antenna has been thoroughly examined and verified. The exploration of the new structure is carried out with a view to eliminate higher order orthogonal resonance without altering its dominant mode field configuration.

Rectangular patch on air and air-dielectric composite substrates to achieve improved radiation characteristics

A rectangular microstrip patch on air and composite (air-PTFE) substrate is theoretically and experimentally investigated and compared with conventional microstrip patch. Around 2–3 dB improvement in peak gain along with broad beam radiation pattern is demonstrated. Both experimental and simulated results are presented.

Recent Computer-Aided Design Techniques for Rectangular Microstrip Antenna

In modern microwave systems, rectangular microstrip patch antennas (RMPAs) are probably the most investigated topics among the planar antennas. There are several methods available in literature, for designing and analyzing such antennas, but most of them are very complex and give only approximate results. In this chapter, we have discussed the most accurate and updated computer-aided design (CAD) formulations related to probe-fed RMPA for computing its fundamental input characteristics (resonant frequency and input impedance) and improving radiation characteristics, i.e. gain and polarization purity (the parameter that signifies how much an RMPA is free from spurious modes). These formulations have evolved in the last decades and have been validated against numerous simulations and measurements. The present CAD formulas for resonant frequency and input impedance can accurately address a wide range of RMPA with patch width to patch length ratio (W/L) from 0.5 to 2.0, a substrate having thickness up to 0.23 λg where λg is the guide wavelength and relative permittivity (εr) ranging over 2.2–10.8. The role of a finite air gap on resonant frequency and gain of an RMPA have also been presented. The chapter will be surely useful to antenna designers to achieve a concrete understanding of the RMPA theory.

Rectangular microstrip antenna with cross headed dumbbell defected patch surface for improved polarization purity

A simple and compact rectangular microstrip antenna with cross headed dumbbell defected patch surface is proposed for noteworthy suppression of cross polarized (XP) radiation, eliminating higher order orthogonal resonance without altering its dominant mode field configuration. The proposed antenna has been studied experimentally with theoretical justifications. More than 28 dB of XP radiation isolation from peak co polarized (CP) radiation is revealed.