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In this paper, a new time-domain (TD) solution is proposed for analyzing the diffraction of ultra wideband (UWB) signals in three dimensional (3-D) scenarios. In this sense, the solution is based on uniform theory of diffraction (UTD) where the diffraction has been considered by obstacles like 3-D wedge and building. The TD solution is derived with the help of frequency-domain (FD) diffraction coefficient existing in the literature that can be used for arbitrary positions of transmitter (Tx) and receiver (Rx). Considering soft and hard polarizations, the TD expressions are obtained for both amplitude diffraction (i.e., single diffraction) and slope diffraction (i.e., double diffraction). The accuracy of the proposed solution is confirmed by comparing the TD results with the rigorous Maliuzhinets solution and also with the numerical inverse fast Fourier transform (IFFT) of the corresponding FD results. The results are shown for diffraction by objects made up of perfectly electrical conducing (PEC) and dielectric materials. It is obserevd that the TD solution exhibits symetery and reciprocity property and thus can predict the diffracted field for any arbitrary position of Tx and Rx. The generalized behavior of the TD solution is confirmed by employing different kinds of excitation pulses at the Tx. Channel impulse response (CIR) is also studied to analyze the pulse shape distortion. Finally it is shown that the proposed TD solution is computationally more efficient than the FD solution.

This paper is about to compare the electrical performance of conventional FD-SOI MOSFET with the BOX integrated substrate SOI MOSFET. The performance is compared and contrasted with the help of electric field, energy band diagram, surface potential, gate material (variation of workfunction) and parasitic capacitances. On comparison the proposed structure shows high Ion/Ioff ratio, high RSP, lower sub-threshold slope and lower threshold voltage then the conventional FD-SOI MOSFET. The performance of the proposed structure is also studied by the variation of buried oxide (BOX) thickness and the overlapped SOI (LSOI) region. Interestingly, by decreasing the thickness of BOX and LSOI region, the leakage current is decreasing without affecting the on-state current and the threshold voltage, thus increasing the Ion/Ioff ratio and decreasing the sub-threshold slope. In addition, this work also shows the improved analog performance in terms of transconductance (gm), gate to drain capacitance (Cgd), gate to source capacitances (Cgs), and cut-off frequency as compared to conventional FD-SOI MOSFET. The comparative study shows that the proposed structure is compatible for the digital as well as analog application without affecting the current fabrication process flow of the conventional FD-SOI MOSFET. Sentaurus two-dimensional simulations are used to analyze the performance of the proposed structure.

In this study, a rhombus-shaped patch antenna is proposed using metamaterial transmission line. The motivation of this work is to overcome the problem of low gain while designing miniaturised antennas. The proposed design is based on coplanar waveguide feeding technique. A rhombus-shaped patch is chosen in this structure in which striplines are provided to connect the ground planes and to obtain the shunt inductance. Asymmetric meandered line inductors are integrated with the striplines for miniaturising the electrical size of the antenna. Further to improve the gain of the antenna in the lower bands, asymmetric ground plane and complementary closed ring resonator have been employed in the proposed structure. The electrical size of the proposed antenna is 0.168 λ 0 × 0.151 λ 0 corresponding to the physical size of 25 mm × 22.5 mm, where λ 0 = free space wavelength at 2.02 GHz. Considering below -10 dB input reflection coefficient, this antenna operates in three bands covering 1.96-2.07, 4.06-4.72, and 6.43-7.79 GHz. In addition, the proposed antenna exhibits gain of 1.49, 2.68, 2.19, and 4.31 dB at 2.02, 4.48, 6.72, and 7.43 GHz, respectively, in the maximum direction of radiation.

Diffraction is a vital propagation mechanism to predict the signal strength and to study the cell coverage in different kinds of scenarios. In this paper, a new heuristic based time-domain (TD) diffraction model is proposed for diffraction of ultra wideband (UWB) signals by lossy obstacles like wedges and buildings. The TD model is derived by using the heuristic frequency-domain (FD) diffraction coefficient that can estimate the radiowave propagation in urban scenarios. The analysis of slope diffraction is also considered to account for double diffraction or grazing incidence where amplitude diffracted field is negligible. Two dimensional (2-D) uniform theory of diffraction (UTD) approach is used for analyzing both soft and hard polarizations. The TD results are compared with the numerical inverse fast Fourier transform (IFFT) of the corresponding FD results with very good agreement between them. The TD solution is also validated by comparison with the IFFT of the Maliuzhinets’ coefficient that can be adopted as reference. Building materials with different electromagnetic properties are considered. To analyze the distortion to the input pulse, the UWB channel impulse response is also investigated. Different excitation pulse types have been employed to confirm the general behavior of the proposed TD solution. Finally the TD and IFFT-FD solutions are compared in the context of their computational time. The TD results can contribute to analyze the UWB pulse shape distortion by diffraction under frequency selective channel.

The Internet Protocol version 6 (IPv6) based routing protocol for low power and lossy networks (RPL) is used for routing in the static networks such as wireless sensor networks (WSNs) and internet of things (IoT). The research is going on to implement the RPL for mobile networks like vehicular ad-hoc network (VANET) and mobile ad-hoc network (MANET). These networks are infrastructure less and self-configuration is required to connect these mobile devices. There are some limitations of the RPL when the network is dense and mobility is introduced in it. For the solution of this problem, this paper presents the performance evaluation of RPL in the mobile network and comparison is performed with the static network. The implementation is done on the Contiki environment and results are analyzed on Cooja (network simulator). It is observed that the RPL performance depends strongly on number of sender nodes, sink nodes, and also on the inclusion of mobility to the nodes. The metric values increase with more packet loss with increasing the number of nodes in the network. Further the increase in number of sink nodes provides lesser packet loss, retransmission, and the energy consumption. The introduced mobility increases the network energy consumption.

Pose estimation of various human activities has seen tremendous progress over the past few decades due to the advancement of computer vision technology. However, the current status of pose estimation is quite stagnated when seen in context to human behaviour analysis by using the pose. In this paper, pose estimation has made significant advancement in terms of dexterity and ingenuity, which is sufficient for human pose estimation. This work includes a large dataset of various human activities. The collected images cover a wide range of human activities that include various activities in various postures in different angles of viewpoints. We have annotated all images for various joint locations such as head, elbow, hands, and eyes via CSV data file. The pose analysis of this work will provide various ongoing research insights about the use of computer vision and Convolution neural networks (ConvNets) for practical purposes and would further instigate this technique as an alternative for VFX in the film industry.

In this paper, a new time-domain (TD) model is proposed for multiple scattering of ultra wideband (UWB) signals through lossy obstacles. Propagation through structures like wedge, single building, and double buildings is presented where buildings are supposed to have rectangular cross sections. Considering two-dimesnional (2-D) and realistic three-dimensional (3-D) scenarios, first an accurate path-tracing algorithm is proposed for multiple scattering of UWB signals through different 2-D and 3-D scenarios and then, TD solution is presented for realistic multiple scattering problems where a single ray-path can undergo diffraction, transmission, and reflection successively. Results are shown for both soft and hard polarizations. Considering Gaussian doublet pulse, the accuracy of the presented TD solution is confirmed by comparing the TD results with the numerical inverse fast Fourier transform (IFFT) of the corresponding frequency-domain (FD) results. It has been found that the field strength at the receiver (Rx) undergoes significant attenuation and distortion for different multiple scattering scenarios. For an in-depth analysis of pulse distortion at Rx, the UWB channel impulse response is analyzed for multiple scattering scenario. Power profile for multiple scattering scenario is also observed to signify the received power at the Rx. To characterize the multipath propagation, UWB multipath is analyzed in terms of time dispersion parameters like mean excess delay and root mean square delay spread. Further to confirm the generality of the proposed TD solution, the results are shown for a variety of other UWB pulses like monocycle and fourth-order Gaussian monocycle pulses. Finally, the computational efficiency of the TD and IFFT-FD methods is compared.

In this paper, a new time-domain (TD) solution is proposed for corner diffraction by finite-edge flat plate structures. First, TD solution is considered for corner amplitude diffraction by edges of...

Millimeter-wave (mm-wave) propagation is considered as one of the potential candidates for future fifth-generation (5G) wireless communication. This paper presents a ray-based deterministic channel modeling for analysis of mmwave propagation in urban scenario. The proposed model is based on uniform theory of diffraction (UTD) and geometrical optics (GO). Different physical mechanisms like diffraction, diffraction followed by reflection, line-of-sight (LOS), and ground reflection have been used to obtain the total field at receiver (Rx). Considering 28 GHz as the potential band for 5G communication, results for mm-wave propagation have been simulated for both soft and hard polarizations and also have been compared with those for current cellular technologies like second-generation (2G), third-generation (3G), and fourth-generation (4G). The analysis reveals that the total field at Rx gets more attenuated with increase in carrier frequency. Finally, the dependence of field strength on different parameters like Rx position, Rx height has been analyzed.

Incurrent scenario theFD-SOI MOSFET considered as one of the potential candidate for higher electrical performance. This paper presents an analysis of developed channel SOI-MOSFET with electric field modulation (DC-EFM FDSOI) in terms of modulation of electric field, variations of front and back oxide thickness and the parasitic capacitance. The concept of DC-EFM has been introduced in the drain region of conventional FD SOI MOSFET in order to improve its threshold voltage, subthreshold slope and the DIBL and reduces the parasitic capacitance. The threshold voltage and drain currenthas been used to investigate the device and also the results have been compared with the different FD-SOI MOSFETavailable in the literature. The device is designed and simulated using the Sentaurus TCAD device simulator.

Millimeter wave (mm-wave) at 60 GHz is a revolutionary technology for ultra-high data rate indoor communications. Unfortunately, due to unfavorable channel characteristics, communication at 60 GHz suffers from poor link budget, high penetration loss and severe signal attenuation. To improve the link budget and the quality of the received signal, the beamforming techniques must be incorporated. In this paper, we derive analytically tractable bit error rate (BER) for the analog beamforming aided mm-wave communication system over the modified IEEE 802.15.3c channel model. It also takes into account the impact of the Rake receivers, which are used to capture the signal energy carried by the multipath components. Monte Carlo simulations have also been carried out to validate the accuracy of the analytical framework. In addition, the impact of Rake’s fingers, power decay factors and arrival times on the BER of the 60 GHz system is also highlighted.

The read and write stability of SRAM cell depends on the high-performance CMOS technologies (FD-SOI technology), due to low power dissipation, and high switching and inter-die variability. This paper first analyzed the electrical behavior of ultrathin body fully depleted silicon-on-insulator (UTB FD-SOI) MOSFET. It is demonstrated that the FD-SOI MOSFET has high Ion to Ioff ratio (better switching) and low threshold voltage. By taking into account of high switching of UTB FD-SOI MOSFET, it is further used to form a 6T SRAM cell. The read and write behavior of 6T SRAM cell has been studied using the read static noise margin (RSNM) and write static noise margin (WSNM). It is observed that the results obtained from the behavior of SNM show that the design of SRAM cell is more robust and highly stable. Further, the results were compared and contrasted with the reported literature, i.e., FinFET- and SOI MOSFET-based SRAM cell. The structures were designed and simulated using Synopsys TCAD device simulator.

In this paper, a new time-domain (TD) three-dimensional dyadic diffraction coefficient is proposed for ultra wideband (UWB) signals with arbitrary polarization and oblique incidence. Simulation results are presented for diffraction by a single wedge, double wedge and building scenario with consecutive diffractions. An excellent agreement of the proposed TD solution with the inverse fast Fourier transform (IFFT) of the corresponding exact frequency-domain (FD) solution proves the validity of the TD solution. Also it is observed that the TD solution is computationally more efficient than the IFFT---FD method. The presented TD solution can be used to analyze diffracted field for arbitrary polarized UWB signals with oblique incidence.

In this article, a new time-domain (TD) corner diffraction coefficient is proposed for diffraction of ultrawide band signals by objects like metallic and dielectric three-dimensional wedge and building. The proposed TD solution has been validated with the inverse fast Fourier transform of the corresponding frequency-domain (FD) solution where the exact match confirms the accuracy of the proposed solution. © 2015 Wiley Periodicals, Inc. Microwave Opt Technol Lett 57:1760–1765, 2015

An analytical time-domain (TD) solution based on an established frequency-domain (FD) transmission model is presented for transmission of ultrawideband (UWB) signals through low-loss dielectric obstacles, in a microcellular and indoor propagation environment. This paper provides an in-depth analysis of the FD transmission model and presents a computationally more efficient direct TD transmission solution. Various obstacles considered in this paper include dielectric wedge and rectangular building with homogeneous, isotropic, and low-loss dielectric characteristics. Novel TD transmission coefficients, for transmission through an interface between air and a low-loss dielectric medium, are proposed for both hard and soft polarizations. The proposed TD solution is validated against the numerical inverse fast Fourier transform of the exact FD (IFFT-FD) solution and the results are found to be in very good agreement with each other. The computational efficiency achieved through the proposed TD solution is demonstrated by comparing its computation time with that of the exact IFFT-FD solution.

In this paper, a new time-domain (TD) three-dimensional (3D) dyadic diffraction coefficient is presented for UWB signals with arbitrary polarization. Simulation results are presented for diffraction through building scenario which covers single and double diffraction. An excellent agreement of the presented TD solution with the inverse fast Fourier transform (IFFT) of the corresponding exact frequency-domain (FD) solution confirms the accuracy of the proposed solution. The proposed TD solution can be used to analyze multiple diffractions for arbitrary polarized signal with oblique incidence.

In this work the time-domain (TD) solution for transmission through a building with multilayer wall structure has been presented. The layers of the walls are considered with different thickness and dielectric materials. The exact frequency-domain (FD) formulation for transmitted field at the receiver (Rx) has been simplified under the condition of low-loss assumption and converted to TD formulation using inverse Laplace transform. The TD results have been validated with the inverse fast Fourier transform (IFFT) of the corresponding exact FD results. Further the computational efficiency of both the methods has been compared.

Pulse-based ultra-wideband (UWB) transmission is the emerging opportunity for modern wireless communication in the microwave and millimeter-wave (mm-wave) frequency ranges. In this frame, monocycle pulse has been emerged as the suitable candidate for next-generation (5G) UWB communication. This paper explores the time-domain (TD) analysis of monocycle pulse propagation in lossy environment. Free Space propagation has been followed by transmission through a wall and then diffraction by a dielectric wedge. The TD results have been presented for both soft and hard polarizations and validated with the inverse fast Fourier transform (IFFT) of the corresponding exact FD results. Finally the computational efficiency of TD and IFFT-FD methods is compared.

Current mirrors are core structures for almost all analog mode circuits and are integral part of a signal processing elements like op amps. The performance of analog structures largely depends on their characteristics. In this paper we present some of the current mirror circuits and analyze their performances, so that one can choose a suitable current mirror for a particular application.

In this work, the time-domain solution for transmission through multi-modeled obstacles has been presented. The transmission through dielectric wedge followed by a dielectric slab has been analyzed. The analytical time-domain transmission and reflection coefficients for transmission through the conductor-dielectric interface, considering oblique incidence, are given for both soft and hard polarizations. The exact frequency-domain formulation for transmitted field at the receiver has been simplified under the condition of low-loss assumption and converted to time-domain formulation using inverse Laplace transform. The time-domain results have been validated with the inverse fast Fourier transform (IFFT) of the corresponding exact frequency-domain results. Further the computational efficiency of both the methods is compared.

In this paper deterministic modeling is used to investigate the field at receiver after multiple diffractions of spherical waves by rectangular building in microcellular scenario at frequencies 2 GHz (for 3G), 5 GHz and 60 GHz (for 4G). Higher order diffraction coefficients (Slope diffraction terms) are used to compute the diffracted field over consecutive wedge faces. Both soft and hard polarizations have been considered. Source is assumed to be above, level with or below the building height. Depending upon transmitter height, ray contributions include single and double order diffraction from building edges, ground reflection, and direct waves.