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In this paper a compact wideband Filtenna structure with stopband characteristics has been presented. The proposed filtenna is a planar elliptical patch with a CSRR structure embedded in the partial ground. The elliptical shape is utilized to attain the wideband characteristics whereas the CSRR is etched out to filter out the undesired bands. This filtenna design exhibits an impedance bandwidth of 3.3 GHz ranging from 2.47 GHz to 5.77 GHz covering the WLAN (2.4/5.2 GHz) and WiMAX (2.5/ 3.5/ 5.5 GHz) bands and effectively rejects the higher bands beyond 5.77 GHz. The designed filtenna achieves a maximum gain of 4.11 dBi and a bidirectional radiation pattern over the desired bandwidth. The overall dimensions of the proposed filtenna is 40 mm x 50 mm x 1.6 mm with the patch area 14 mm x 10 mm. The proposed filtenna is designed, simulated and optimized using CST Microwave Studio and has been fabricated and tested to validate the proposed design.

Agriculture has been the backbone of our country's economy and it will remain to continue for a long time. Over 70 percent of the rural population depends on agriculture. The contribution of agriculture to the gross domestic product (GDP) is about to 18% and have contributed up to 50% of the country's employment. The prognosis indicates that requirement to feed a world population of 9.1 billion people in 2050 necessitates the raise of total meal production nearby 70% between 2005 and 2050. Consequently, production would need to be almost doubled in the developing countries. In this context, we have proposed a new design concept of smart drip irrigation system for remote hilly areas where electricity and water connectivity are poor. The proposed system is powered through solar energy and provide a better alternative to conventional automatic irrigation systems. Thus, conserve electricity and water by reducing their usage.

A novel structure of three dimensional Cylindrical Shaped Frequency Selective Surface (CSFSS) has been structured and its polarization sensitivity has been analyzed. The effect of oblique angle of incident electromagnetic wave on the CSFSS by varying the circumference of the outer ring has been observed. The analysis has been made for oblique incident angles from 0° to 60°. The resultant frequency response reveals that the CSFSS structure has been found highly polarization insensitive and obtained a stable transmission response with respect to incident EM wave. Moreover, an analysis has been made to find out the effect of variation of the circumference on the resonant frequency and result shows a highly sensitive and interesting relation between them.

The three dimension cylindrical structure is interesting, challenging and offers excellent space utilization. With utilization of three-dimensional space, the unit cell size of the FSS can be further reduced. A novel design of three dimensional Cylindrical Shaped Frequency Selective Surface (CSFSS) based on a single circular ring structure has been proposed. Firstly, a circular ring has been chosen and its frequency response has been studied. Then by keeping all the parameter same a CSFSS structure has been drawn with varying height. A significant influence on the frequency response characteristics of the CSFSS viz a viz a stop-band and pass-band frequency response behavior has been observed. A polarization sensitivity analysis has been done for the TE and TM modes for oblique angle of incidence. A full width half maximum (FWHM) bandwidth analysis of CSFSS is also observed. By varying the parameters of the CSFSS, the resonant frequency could be tuned. A parametric analysis of the CSFSS is done. The widespread potential applications of the proposed CSFSS are found in area of communication, microwave and radar systems.

In this research work, the design characterization of metamaterial absorber has been investigated for X-band applications. For this purpose, a primary regular decagon shaped loop structure has chosen and its multi band response has been studied and analyzed. The simulated results show that absorption peaks occur at 8 GHz, 10 GHz and 12 GHz with absorbance peak response of 96 %, 93.36 % and 91.88 % with full width at half maximum (FWHM) bandwidth of 5.72 %, 4.00 % and 3.80 % respectively. By proper arrangement, we have achieved the absorption peaks for triple frequency band at incident electromagnetic wave. The scalability property of metamaterials was utilized. Field analysis reveals that the frequency selective surface (FSS) unit cell absorbers resonance peaks occur, when the intrinsic impedance of the regular decagon shaped structure matches with the free space impedance. The proposed absorber is predicted to be useful in various potential applications like stealth technology for aircraft, ships, military vehicles, ballistic missiles. Moreover, the design idea has the ability to be extended further to microwave, optical and terahertz regime.