A double square loop based compact, ultrathin, polarization and incident angle insensitive metama... more A double square loop based compact, ultrathin, polarization and incident angle insensitive metamaterial absorber has been presented in this manuscript. The unit cell of the proposed design comprises of double square loop on the top surface of a metal grounded dielectric substrate. The proposed design is compact with its unit cell size of 9.5 mm, i.e., λ 0 /4.4 and ultrathin with the overall thickness of 0.038 λ 0 corresponding to the highest frequency of operation. The simulated results show dual absorption peaks at 3.99 and 7.15 GHz with absorptivity of 65.94% and 88.65%, respectively. The design is polarization and incident angle insensitive. The structure shows more than 90% absorptivity at both the absorption frequencies for the incidence angle of 60°. A prototype of the proposed absorber design has been fabricated and its performance has been experimentally verified for normal and oblique incidences for TE and TM polarization. The measured results are observed to be in agreemen...
The wireless power transmission (WPT) technology is an extension of wireless communication. The p... more The wireless power transmission (WPT) technology is an extension of wireless communication. The physics of WPT and wireless communication are related, but WPT is distinct from wireless transmission for transferring information (such as radio and mobile phones etc.), where the percentage of the power that is received is only important if it becomes too low to successfully recover the signal. With WPT, the efficiency is a more critical parameter and this creates important differences in these technologies. This paper presents the wireless power transmission (WPT), from past work to most recent accomplishments including recent developments, potential approaches and factors responsible for designing most critical rectifying diodes operating at terahertz/petahertz frequencies.
Vehicular ad-hoc network (VANET) is a network that allows mobile communication between road side ... more Vehicular ad-hoc network (VANET) is a network that allows mobile communication between road side to vehicle and vehicle to vehicle. In this paper, a brief introduction of VANETS, its protocol structure, broadcasting, and information dissemination has been discussed. Different types of routing & communication protocols like vehicular collision warning communication (VCWC), vehicle heading based routing protocol (VHRP) and routing protocol related to VANETs has also been discussed. The crosslink removal technique by GEOCROSS routing protocol has been reviewed. But that algorithm is not able to remove the cross edge problem. So, to overcome that problem new algorithm has been proposed in this paper.
Sensors, FETs and chemi resistors are few of the devices which show potential in the area of flex... more Sensors, FETs and chemi resistors are few of the devices which show potential in the area of flexible electronics for health monitoring applications. In the present work, piezoresistive strain sensors based on graphite and graphene on cellulose paper substrate has been reported. Graphite sensor has been fabricated by rubbing pencil on paper and graphene sensor by directly coating graphene ink using paint brush. The resistance of the fabricated sensor increases with outwards bending and vice-versa, further the piezoresistive effect has also been evaluated by applying variable longitudinal stress. A comparative study of gauge factor (GF) depending upon different type of strains has been presented and it has been observed that the GF of graphene piezoresistive strain sensor decreases with increase in number of layers, the GF for graphene sensor is higher as compared to graphite sensor. Fabricated piezoresistive strain sensors may find applications as human body motion detection, gait a...
Abstract Carbon based nanomaterials are frequently used for the fabrication of flexible electroni... more Abstract Carbon based nanomaterials are frequently used for the fabrication of flexible electronic devices in past few years. Graphene and carbon nanotubes (CNTs) are the carbon nanomaterials known for their superior and adaptable properties to be used as a conductive filler in flexible sensors. In this work, graphene/CNT composite based strain sensors were fabricated on polymer substrate by using a simple fabrication technique. Conductive thin film of the graphene/CNT composite was formed and designed into two different structures i.e. ‘I' and ‘Serpentine’ to enhance the sensing performance of the film. The electrical performances were observed in the form of I-V characteristics and the resistive behavior of all the fabricated samples are reported. For both cases, significant variation in relative resistance was observed during bending of the sensors at various radius of curvature. The relative variation of resistance in serpentine structured samples were significantly high in comparison to ‘I' structured samples. The sensitivity was defined by the measurements of relative resistance variation against level of strain from 0.1% to 0.6% and a gauge factor of 67 and 96 was observed for ‘I' and ‘Serpentine’ structures respectively. To demonstrate the potential application, the fabricated sensors were implemented for the measurements of finger movements at various angles (from 00 to 900) and significant change in resistance of the sensors were observed. The durability of the fabricated sensors were tested over 1000 cycles at a strain of 0.3%.
Film bulk acoustic wave resonators (FBARs) are of great interest for wireless applications due to... more Film bulk acoustic wave resonators (FBARs) are of great interest for wireless applications due to its inherent advantages at microwave frequencies. However, the presence of spurious modes near the main resonance degrades the performance of resonators and requires development of new methods to suppress such unwanted modes. Different techniques are used to suppress these spurious modes. In this paper, we present design of a new step-like frame structure film bulk acoustic wave resonator operating near 1.5 GHz. The simulated results are compared with simple frame-like structure. The spurious resonances are eliminated effectively and smooth pass band is obtained with effective coupling coefficient of 5.68% and quality factor of 1800. The equivalent electrical mBVD model of the FBAR based on impedance response is also presented. These highly smooth phase response and passband skirt steepness resonators are most demanding for the design of low cost, small size and high performance filters...
This paper provides a complete state-of-the-art of reconfigurable antennae viz. frequency reconfi... more This paper provides a complete state-of-the-art of reconfigurable antennae viz. frequency reconfigurable antennae, radiation pattern reconfigurable antennae, polarization reconfigurable antennae, and combination of radiation and frequency reconfigurable antennae from the literature. Of late, reconfigurable antennae have received a lot of attention for their applications in diversified areas like communication, surveillance etc. This is owing to their ability to modify their radiation characteristics, frequency of operation, polarization or even a combination of these features in real time. Reconfigurable antennae have the potential to add substantial degrees of freedom and functionality to mobile communication and phase array systems. Reconfigurability in antennae allows us for spectrum reallocation in multi-band communication systems, dynamic spectrum management, therefore reducing the number and size of antennae in a system.
Present article reports on reduced graphene oxide (rGO) modified poly(3,4-ethylenedioxythiophene)... more Present article reports on reduced graphene oxide (rGO) modified poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT: PSS) based transparent conducting electrodes for flexible optoelectronic applications. PEDOT: PSS samples embedded with different rGO concentrations i.e. 0, 1, 2, 3, 4, 5 wt% were prepared and later on, bar coated on polyethylene terephthalate substrate using a 30 μm wire size bar. Various parameters including sheet resistance, bending test (outside and inside bending), optical transmittance etc. were estimated. Our analysis indicates that the samples with 1 wt% rGO possess improved results i.e. low sheet resistance (315 ± 8 Ω/sq.) and high transmittance (~ 74%). Additionally, the sample shows low electrical resistance variation up to 12% (maximum increase) during outward bending and 9% (maximum decrease) during inward bending of the sample for bending curvature from 20 to 100 m−1.
International Journal of Scientific Research in Science and Technology, 2015
In this paper, a MEMS-based Z-axis capacitive accelerometer is designed and simulated. An out-of-... more In this paper, a MEMS-based Z-axis capacitive accelerometer is designed and simulated. An out-of-plane Z-axis accelerometer designed for 8 µm UV-LIGA technology for an acceleration range of ±10g. The operating voltage is 5 V DC. Simulation results show good linear characteristics in the operating range of DC-400 Hz, which is the bandwidth of the accelerometer. The simulations of the device were carried out using CoventorWare ® . By using modal analysis in CoventorWare ® the resonating frequency of 3.1 kHz is obtained.
Materials Science in Semiconductor Processing, 2016
Diffusion barrier properties of CoNiO monolayer, deposited by Langmuir Blodgett (LB) technique, w... more Diffusion barrier properties of CoNiO monolayer, deposited by Langmuir Blodgett (LB) technique, were studied against the diffusion of copper through SiO 2 . Cu/CoNiO/SiO 2 /Si and Cu/SiO 2 /Si test structures were prepared and compared for this purpose. These test structures were annealed at temperatures starting from 100 °C up to 650 °C in vacuum. Samples were characterized using Energy Dispersive X-ray Spectroscopy (EDS), Atomic force microscopy (AFM), X-ray diffraction (XRD), scanning electron microscope (SEM), four probe resistivity measurement, Capacitance-Voltage (C‒V), Current-Voltage (I‒V) characterization techniques. EDS and AFM confirmed the composition and structure of the deposited monolayer. Thermal stability was studied using X-ray diffraction (XRD), Scanning Electron Microscope (SEM) and four probe techniques. Results indicated that structure with barrier was stable up to 600 °C whereas its counterpart could sustain only up to 300 °C. Sheet resistance of Cu/SiO 2 /Si ...
2017 International Conference on Computer, Communications and Electronics (Comptelix)
The paper presents an exhaustive visualization of different problems encountered in efficient uti... more The paper presents an exhaustive visualization of different problems encountered in efficient utilization of spectrum for advanced wireless communication. It is a well known fact that there is a crisis for available radio spectrum due to incredible expansion and advancement of the communication systems and technologies. But in reality, there is no shortage of available spectrum but only lack of advance techniques for perfect utilization of spectrum. So, to tackle the future spectrum implications, the new emerging field of Cognitive Radio is explored here. Cognitive Radio has potential to revolutionize the way of spectrum allocation scheme worldwide because it can recognize spectrum condition and reconfigure itself to optimize its operation to compete with growing demands of the spectrum. In this paper, complete description and working operation of Cognitive Radio is presented. The paper provides special emphasis on various aspects of Cognitive Radio like different spectrum sensing methods and spectrum sharing schemes with the appropriate mathematical formulation. To facilitate implementation of this idea, new design requirement on antenna's features is thoroughly explained here.
In this we propose a new method to reduce noise in digital image. Image corrupted by Gaussian Noi... more In this we propose a new method to reduce noise in digital image. Image corrupted by Gaussian Noise still a classical problem. To reduce the noise or to improve the quality of image compare peak signal to noise ratio (PSNR). Higher the PSNR better the quality of the image. In this paper, we discuss pervious method like VisuShrink, BaseShrink, SureShrink, NeighShrink all these in brief. There we also discuss the advantages and disadvantages of these methods. In this paper we explain the method improved NeighShrink. With the help of discrete wavelet technique we decompose the image in to wavelets. By applying the median filter on the wavelets we get the better results. Experimental results show that our method gives comparatively higher peak signal to noise ratio (PSNR), are much more efficient and have less visual artifacts compared to other methods.
Microstrip patch antenna array to be used for X-band short-range microwave applications has been ... more Microstrip patch antenna array to be used for X-band short-range microwave applications has been introduced. This antenna maintains a maximum gain of 14.6 dB for far field region w.r.t paraboloidal rectangular aperture antenna. It is actually a probe (coaxial) fed antenna with quarter wave sections that are fabricated as an arrangement for impedance matching with 50 Ω coaxial cable. This antenna works well in the frequency range 8.45-9.33 GHz with a maximum at 8.53 GHz. It is basically a low cost, lightweight, medium gain and narrowband antenna and suited for short-range microwave applications such as a feeding element for other antennas and in research institutes as a reference antenna. It can also be used at the output of signal conditioning circuit for receiving signals from micro electromechanical sensors.
Owing to Moore’s law and the advancements in microelectronics, the industry is shifting to nanoel... more Owing to Moore’s law and the advancements in microelectronics, the industry is shifting to nanoelectronics. The materials used for nanoelectronics applications are termed as nanomaterials recognized as the one which has at least one dimension less than 100 nm. Nanoelectronics allows bottom-up approach in contrast to the top-down approach adopted in microelectronics. So in nanoelectronics, the approach is to design systems using nanomaterials as basic building blocks. The importance of nanoelectronics is that different nanomaterials exhibit certain unusual properties not available at the micro scale. These unusual properties of the nanomaterials are utilized in a wide range of electronic applications like sensors, FETs, photovoltaic cells and many other exotic electronic devices applications. Graphene is one of the most recently discovered nanomaterial known for its exceptional mechanical, electrical, optical properties which are not found in any other material in the world. Being th...
The develpoment of smart antennas for mobile phones has recently recevied much interest due to co... more The develpoment of smart antennas for mobile phones has recently recevied much interest due to compact size of multimode phones and requirements to keep the amount of RF power absorbed by a user below a certain level. In this paper a new Yagi Uda shaped frequency reconfigurable antenna for multimode mobile applications has been presented. The proposed fabricated antenna have return loss better than -10dB, VSWR below 2, radaiation efficiency greater than 60% and SAR below 2W/kg for all the frequency bands. The proposed antenna structure is compact in size, offer high isolation between eight transmitting bands. PIN diodes are used to switch the frequecny bands between WCDMA, FDMA, PDC, GPS (1.56-1.585 GHz), GSM1800 (1710-1880MHz), PCS1900 (1859-1990MHz), UMTS (1900-2170MHz), DCS1800, WLAN, Bluetooth, Wi-Fi etc.
In this paper, design, characterization and measurements of an ultrathin compact polarization ins... more In this paper, design, characterization and measurements of an ultrathin compact polarization insensitive triple band metamaterial absorber for wide incident angle have been presented. The unit cell design consists of a Jerusalem cross shaped resonator inside a square loop resonator. The proposed absorber exhibits triple band absorption at 4.4, 6.48 and 15.44 GHz with 96.6% and 97.64% and 85.81% absorptivity, respectively, for wide incident angles of electromagnetic wave. The absorption frequencies can be effectively adjusted for C, X and Ku frequency bands by optimizing the dimensions of the absorber design. The proposed absorber is ultrathin (0.014 λ 0 ) in thickness and compact (0.12 λ 0 ) in size at the lowest frequency of absorption. The proposed absorber exhibits TE and TM polarization stability and provides high absorption up to the incident angle of 60°. A prototype of the proposed absorber structure has been fabricated and experimentally tested for normal and oblique incide...
A double square loop based compact, ultrathin, polarization and incident angle insensitive metama... more A double square loop based compact, ultrathin, polarization and incident angle insensitive metamaterial absorber has been presented in this manuscript. The unit cell of the proposed design comprises of double square loop on the top surface of a metal grounded dielectric substrate. The proposed design is compact with its unit cell size of 9.5 mm, i.e., λ 0 /4.4 and ultrathin with the overall thickness of 0.038 λ 0 corresponding to the highest frequency of operation. The simulated results show dual absorption peaks at 3.99 and 7.15 GHz with absorptivity of 65.94% and 88.65%, respectively. The design is polarization and incident angle insensitive. The structure shows more than 90% absorptivity at both the absorption frequencies for the incidence angle of 60°. A prototype of the proposed absorber design has been fabricated and its performance has been experimentally verified for normal and oblique incidences for TE and TM polarization. The measured results are observed to be in agreemen...
The wireless power transmission (WPT) technology is an extension of wireless communication. The p... more The wireless power transmission (WPT) technology is an extension of wireless communication. The physics of WPT and wireless communication are related, but WPT is distinct from wireless transmission for transferring information (such as radio and mobile phones etc.), where the percentage of the power that is received is only important if it becomes too low to successfully recover the signal. With WPT, the efficiency is a more critical parameter and this creates important differences in these technologies. This paper presents the wireless power transmission (WPT), from past work to most recent accomplishments including recent developments, potential approaches and factors responsible for designing most critical rectifying diodes operating at terahertz/petahertz frequencies.
Vehicular ad-hoc network (VANET) is a network that allows mobile communication between road side ... more Vehicular ad-hoc network (VANET) is a network that allows mobile communication between road side to vehicle and vehicle to vehicle. In this paper, a brief introduction of VANETS, its protocol structure, broadcasting, and information dissemination has been discussed. Different types of routing & communication protocols like vehicular collision warning communication (VCWC), vehicle heading based routing protocol (VHRP) and routing protocol related to VANETs has also been discussed. The crosslink removal technique by GEOCROSS routing protocol has been reviewed. But that algorithm is not able to remove the cross edge problem. So, to overcome that problem new algorithm has been proposed in this paper.
Sensors, FETs and chemi resistors are few of the devices which show potential in the area of flex... more Sensors, FETs and chemi resistors are few of the devices which show potential in the area of flexible electronics for health monitoring applications. In the present work, piezoresistive strain sensors based on graphite and graphene on cellulose paper substrate has been reported. Graphite sensor has been fabricated by rubbing pencil on paper and graphene sensor by directly coating graphene ink using paint brush. The resistance of the fabricated sensor increases with outwards bending and vice-versa, further the piezoresistive effect has also been evaluated by applying variable longitudinal stress. A comparative study of gauge factor (GF) depending upon different type of strains has been presented and it has been observed that the GF of graphene piezoresistive strain sensor decreases with increase in number of layers, the GF for graphene sensor is higher as compared to graphite sensor. Fabricated piezoresistive strain sensors may find applications as human body motion detection, gait a...
Abstract Carbon based nanomaterials are frequently used for the fabrication of flexible electroni... more Abstract Carbon based nanomaterials are frequently used for the fabrication of flexible electronic devices in past few years. Graphene and carbon nanotubes (CNTs) are the carbon nanomaterials known for their superior and adaptable properties to be used as a conductive filler in flexible sensors. In this work, graphene/CNT composite based strain sensors were fabricated on polymer substrate by using a simple fabrication technique. Conductive thin film of the graphene/CNT composite was formed and designed into two different structures i.e. ‘I' and ‘Serpentine’ to enhance the sensing performance of the film. The electrical performances were observed in the form of I-V characteristics and the resistive behavior of all the fabricated samples are reported. For both cases, significant variation in relative resistance was observed during bending of the sensors at various radius of curvature. The relative variation of resistance in serpentine structured samples were significantly high in comparison to ‘I' structured samples. The sensitivity was defined by the measurements of relative resistance variation against level of strain from 0.1% to 0.6% and a gauge factor of 67 and 96 was observed for ‘I' and ‘Serpentine’ structures respectively. To demonstrate the potential application, the fabricated sensors were implemented for the measurements of finger movements at various angles (from 00 to 900) and significant change in resistance of the sensors were observed. The durability of the fabricated sensors were tested over 1000 cycles at a strain of 0.3%.
Film bulk acoustic wave resonators (FBARs) are of great interest for wireless applications due to... more Film bulk acoustic wave resonators (FBARs) are of great interest for wireless applications due to its inherent advantages at microwave frequencies. However, the presence of spurious modes near the main resonance degrades the performance of resonators and requires development of new methods to suppress such unwanted modes. Different techniques are used to suppress these spurious modes. In this paper, we present design of a new step-like frame structure film bulk acoustic wave resonator operating near 1.5 GHz. The simulated results are compared with simple frame-like structure. The spurious resonances are eliminated effectively and smooth pass band is obtained with effective coupling coefficient of 5.68% and quality factor of 1800. The equivalent electrical mBVD model of the FBAR based on impedance response is also presented. These highly smooth phase response and passband skirt steepness resonators are most demanding for the design of low cost, small size and high performance filters...
This paper provides a complete state-of-the-art of reconfigurable antennae viz. frequency reconfi... more This paper provides a complete state-of-the-art of reconfigurable antennae viz. frequency reconfigurable antennae, radiation pattern reconfigurable antennae, polarization reconfigurable antennae, and combination of radiation and frequency reconfigurable antennae from the literature. Of late, reconfigurable antennae have received a lot of attention for their applications in diversified areas like communication, surveillance etc. This is owing to their ability to modify their radiation characteristics, frequency of operation, polarization or even a combination of these features in real time. Reconfigurable antennae have the potential to add substantial degrees of freedom and functionality to mobile communication and phase array systems. Reconfigurability in antennae allows us for spectrum reallocation in multi-band communication systems, dynamic spectrum management, therefore reducing the number and size of antennae in a system.
Present article reports on reduced graphene oxide (rGO) modified poly(3,4-ethylenedioxythiophene)... more Present article reports on reduced graphene oxide (rGO) modified poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT: PSS) based transparent conducting electrodes for flexible optoelectronic applications. PEDOT: PSS samples embedded with different rGO concentrations i.e. 0, 1, 2, 3, 4, 5 wt% were prepared and later on, bar coated on polyethylene terephthalate substrate using a 30 μm wire size bar. Various parameters including sheet resistance, bending test (outside and inside bending), optical transmittance etc. were estimated. Our analysis indicates that the samples with 1 wt% rGO possess improved results i.e. low sheet resistance (315 ± 8 Ω/sq.) and high transmittance (~ 74%). Additionally, the sample shows low electrical resistance variation up to 12% (maximum increase) during outward bending and 9% (maximum decrease) during inward bending of the sample for bending curvature from 20 to 100 m−1.
International Journal of Scientific Research in Science and Technology, 2015
In this paper, a MEMS-based Z-axis capacitive accelerometer is designed and simulated. An out-of-... more In this paper, a MEMS-based Z-axis capacitive accelerometer is designed and simulated. An out-of-plane Z-axis accelerometer designed for 8 µm UV-LIGA technology for an acceleration range of ±10g. The operating voltage is 5 V DC. Simulation results show good linear characteristics in the operating range of DC-400 Hz, which is the bandwidth of the accelerometer. The simulations of the device were carried out using CoventorWare ® . By using modal analysis in CoventorWare ® the resonating frequency of 3.1 kHz is obtained.
Materials Science in Semiconductor Processing, 2016
Diffusion barrier properties of CoNiO monolayer, deposited by Langmuir Blodgett (LB) technique, w... more Diffusion barrier properties of CoNiO monolayer, deposited by Langmuir Blodgett (LB) technique, were studied against the diffusion of copper through SiO 2 . Cu/CoNiO/SiO 2 /Si and Cu/SiO 2 /Si test structures were prepared and compared for this purpose. These test structures were annealed at temperatures starting from 100 °C up to 650 °C in vacuum. Samples were characterized using Energy Dispersive X-ray Spectroscopy (EDS), Atomic force microscopy (AFM), X-ray diffraction (XRD), scanning electron microscope (SEM), four probe resistivity measurement, Capacitance-Voltage (C‒V), Current-Voltage (I‒V) characterization techniques. EDS and AFM confirmed the composition and structure of the deposited monolayer. Thermal stability was studied using X-ray diffraction (XRD), Scanning Electron Microscope (SEM) and four probe techniques. Results indicated that structure with barrier was stable up to 600 °C whereas its counterpart could sustain only up to 300 °C. Sheet resistance of Cu/SiO 2 /Si ...
2017 International Conference on Computer, Communications and Electronics (Comptelix)
The paper presents an exhaustive visualization of different problems encountered in efficient uti... more The paper presents an exhaustive visualization of different problems encountered in efficient utilization of spectrum for advanced wireless communication. It is a well known fact that there is a crisis for available radio spectrum due to incredible expansion and advancement of the communication systems and technologies. But in reality, there is no shortage of available spectrum but only lack of advance techniques for perfect utilization of spectrum. So, to tackle the future spectrum implications, the new emerging field of Cognitive Radio is explored here. Cognitive Radio has potential to revolutionize the way of spectrum allocation scheme worldwide because it can recognize spectrum condition and reconfigure itself to optimize its operation to compete with growing demands of the spectrum. In this paper, complete description and working operation of Cognitive Radio is presented. The paper provides special emphasis on various aspects of Cognitive Radio like different spectrum sensing methods and spectrum sharing schemes with the appropriate mathematical formulation. To facilitate implementation of this idea, new design requirement on antenna's features is thoroughly explained here.
In this we propose a new method to reduce noise in digital image. Image corrupted by Gaussian Noi... more In this we propose a new method to reduce noise in digital image. Image corrupted by Gaussian Noise still a classical problem. To reduce the noise or to improve the quality of image compare peak signal to noise ratio (PSNR). Higher the PSNR better the quality of the image. In this paper, we discuss pervious method like VisuShrink, BaseShrink, SureShrink, NeighShrink all these in brief. There we also discuss the advantages and disadvantages of these methods. In this paper we explain the method improved NeighShrink. With the help of discrete wavelet technique we decompose the image in to wavelets. By applying the median filter on the wavelets we get the better results. Experimental results show that our method gives comparatively higher peak signal to noise ratio (PSNR), are much more efficient and have less visual artifacts compared to other methods.
Microstrip patch antenna array to be used for X-band short-range microwave applications has been ... more Microstrip patch antenna array to be used for X-band short-range microwave applications has been introduced. This antenna maintains a maximum gain of 14.6 dB for far field region w.r.t paraboloidal rectangular aperture antenna. It is actually a probe (coaxial) fed antenna with quarter wave sections that are fabricated as an arrangement for impedance matching with 50 Ω coaxial cable. This antenna works well in the frequency range 8.45-9.33 GHz with a maximum at 8.53 GHz. It is basically a low cost, lightweight, medium gain and narrowband antenna and suited for short-range microwave applications such as a feeding element for other antennas and in research institutes as a reference antenna. It can also be used at the output of signal conditioning circuit for receiving signals from micro electromechanical sensors.
Owing to Moore’s law and the advancements in microelectronics, the industry is shifting to nanoel... more Owing to Moore’s law and the advancements in microelectronics, the industry is shifting to nanoelectronics. The materials used for nanoelectronics applications are termed as nanomaterials recognized as the one which has at least one dimension less than 100 nm. Nanoelectronics allows bottom-up approach in contrast to the top-down approach adopted in microelectronics. So in nanoelectronics, the approach is to design systems using nanomaterials as basic building blocks. The importance of nanoelectronics is that different nanomaterials exhibit certain unusual properties not available at the micro scale. These unusual properties of the nanomaterials are utilized in a wide range of electronic applications like sensors, FETs, photovoltaic cells and many other exotic electronic devices applications. Graphene is one of the most recently discovered nanomaterial known for its exceptional mechanical, electrical, optical properties which are not found in any other material in the world. Being th...
The develpoment of smart antennas for mobile phones has recently recevied much interest due to co... more The develpoment of smart antennas for mobile phones has recently recevied much interest due to compact size of multimode phones and requirements to keep the amount of RF power absorbed by a user below a certain level. In this paper a new Yagi Uda shaped frequency reconfigurable antenna for multimode mobile applications has been presented. The proposed fabricated antenna have return loss better than -10dB, VSWR below 2, radaiation efficiency greater than 60% and SAR below 2W/kg for all the frequency bands. The proposed antenna structure is compact in size, offer high isolation between eight transmitting bands. PIN diodes are used to switch the frequecny bands between WCDMA, FDMA, PDC, GPS (1.56-1.585 GHz), GSM1800 (1710-1880MHz), PCS1900 (1859-1990MHz), UMTS (1900-2170MHz), DCS1800, WLAN, Bluetooth, Wi-Fi etc.
In this paper, design, characterization and measurements of an ultrathin compact polarization ins... more In this paper, design, characterization and measurements of an ultrathin compact polarization insensitive triple band metamaterial absorber for wide incident angle have been presented. The unit cell design consists of a Jerusalem cross shaped resonator inside a square loop resonator. The proposed absorber exhibits triple band absorption at 4.4, 6.48 and 15.44 GHz with 96.6% and 97.64% and 85.81% absorptivity, respectively, for wide incident angles of electromagnetic wave. The absorption frequencies can be effectively adjusted for C, X and Ku frequency bands by optimizing the dimensions of the absorber design. The proposed absorber is ultrathin (0.014 λ 0 ) in thickness and compact (0.12 λ 0 ) in size at the lowest frequency of absorption. The proposed absorber exhibits TE and TM polarization stability and provides high absorption up to the incident angle of 60°. A prototype of the proposed absorber structure has been fabricated and experimentally tested for normal and oblique incide...
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