Narula Institute of Technology

About: Narula Institute of Technology is a based out in . It is known for research contribution in the topics: Quantum dot cellular automaton & Cognitive radio. The organization has 288 authors who have published 490 publications receiving 2258 citations. The organization is also known as: NiT.

Cubic versus hexagonal SiC vertical pin SPST/SPDT/SPMT switches for MMW communication systems: a modified quantum drift-diffusion model for switching characteristics analysis

Abstract: A modified quantum drift-diffusion (QDD) model is developed for non-linear analysis of SiC (4H, 6H and 3C polytypes) pin semiconductor diodes at W-band frequency regime. Effects of incorporation of a buffer layer (n-type), in between substrate and low doped active region of the hexagonal (4H and 6H) pin (p++-p+-n−-n-n++) vertical mesa structure is thoroughly studied in this paper for the improvement of MM-wave performance of the single device. Also, a thin layer of Ge has been introduced in between Si substrate and n+ cubic-SiC layer in 3C-SiC pin-device for minimising the lattice mismatch issue in between Si/3C-SiC interface. The comprehensive analysis establish that the forward characteristics, reverse recovery time (1 ns) and breakdown voltage (171 Volt) in case of 4H-SiC device are quite good in comparison to its cubic (3C) and other hexagonal (6H) counterparts, however, the switching characteristics of 3C-SiC pin diode array is comparatively better than its hexagonal counterparts. This observation could be explained in terms of lowest series resistance in 3C-SiC based single pin device that has been achieved by incorporating Ge layer in mesa structure. The authors have made a comparative analysis among SPST, SPDT and SPMT pin switches made up with 4H, 6H and 3C-SiC poly-types. At 94 GHz, W-band central frequency, series resistance in 4H-SiC single device is 0.59 Ω, whereas, the same is much lower (0.27 Ω) in case of 3C-SiC. Insertion loss and isolation in 3C-SiC pin array of switches are found to be 0.18 dB and 38 dB (SPST switch), 0.19 dB and 67 dB (SPDT switch), 0.20 dB and 90 dB (SPMT shunt type switching array) and 0.23 dB and 74 dB (SPMT series-shunt type switching array). This newly proposed QDD model validation is done through comparative studies between experiment and analytical results for 4H-SiC SPST switches in low-frequency Microwave region. The validated QDD model, coupled with PSpice and Comsol Multi-physics simulator, then used for designing of the W-band devices and corresponding switches. However, as far as author’s knowledge is concerned, no experiment is yet done with SiC pin diodes at W-band frequencies, in literature for comparison. From simulation point of view also such an extensive study on hexagonal and cubic SiC pin diode switches at W-band region has not yet been done by any other researcher group. This paper, for the first time, establishes the feasibility and potentiality of IV-IV group semiconductor based pin (p++-p+-n−-n-n++) switches for W-band applications. Comparative analysis also reveals that 3C-SiC based shunt type pin (p++-p+-n−-n-n++) SPMT switches are the best for MMW-communication systems. Thermal modelling of the designed devices are also compared and reported in this paper. The quasi-3D thermal analysis is done to optimize the mesa and heat-sink diameter/dimensions so as to minimize the thermal runaway issues. The results may further be used for developing low-cost and fast semiconductor switches for potential application in THz communication systems.

An Ensemble Learning-Based Language Identification System

Abstract: Speech recognition from multilingual voice signals is a challenging task. It is essential to distinguish the language of the spoken phrases prior to recognizing them. This is known as automatic language identification. Automatic language identification is very much important for multilingual countries like India as people often use more than a single language while talking. In this paper, a language identification system for seven different languages from the IIIT-H Indic Speech Databases is presented. We have used line spectral frequency-based features for modelling the languages. The highest accuracy of 99.71% has been obtained with ensemble learning-based classification technique.

QoS and Mobility Management Issues on Next Generation Mobile WiMAX Networks

Abstract: Selection of a MIMO (Multiple Input Multiple Output) antenna to achieve high throughput, minimize errors, and optimize data speed is an important design issue. Radio resource management to provide Quality of Service (QoS) in WiMAX involves dynamic scheduling of resources according to the user’s priority, based classes Platinum, Gold, Silver, and Bronze. Mobility and handoff management in WiMAX is another important issue involving location update, signaling traffic and service delay, and call blocking and dropping. This chapter focuses on some issues concerning MIMO configuration to improve transmit diversity, developing an appropriate scheduling algorithm to improve QoS, and presenting a novel mobility management protocol THMIP (Three Level Hierarchical Mobile IP) in IEEE 802.16e environment to reduce signaling cost with respect to QoS parameters like throughput, end-to-end delay, interference, path loss, bit error rate, and Signal-to-Noise Ratio (SNR). For the simulation, the authors use OPNET Modeler and MATLAB.

Investigation of cross sensitivity of single and double electrode of admittance type level measurement

Abstract: Level measurements of liquid material are one of the important parameters in a process industry. Low cost admittance type liquid level measuring system using single electrode with conducting vessel and double electrode with insulating vessel already exist. In the present work, attempts have been made to study the cross sensitivity of temperature in the admittance type liquid level measurement. The cross sensitivity in the admittance measurement due to temperature is considered for admittance calculations. Error curves due to cross sensitivity for both single electrode and double electrode are simulated using MATLAB. The cross sensitivity due to temperature has been found significant and can be used for simultaneous measurement of temperature and liquid level.

Observational constraints of modified Chaplygin gas in RS II brane

Abstract: FRW universe in RS II braneworld model filled with a combination of dark matter and dark energy in the form of modified Chaplygin gas (MCG) is considered. It is known that the equation of state (EoS) for MCG is a three-variable equation determined by A, α and B. The permitted values of these parameters are determined by the recent astrophysical and cosmological observational data. Here we present the Hubble parameter in terms of the observable parameters Ω m0, Ω x0, H 0, redshift z and other parameters like A, B, C and α. From Stern data set (12 points), we have obtained the bounds of the arbitrary parameters by minimizing the χ 2 test. The best-fit values of the parameters are obtained by 66 %, 90 % and 99 % confidence levels. Next due to joint analysis with BAO and CMB observations, we have also obtained the bounds of the parameters (B,C) by fixing some other parameters α and A. The best fit value of distance modulus μ(z) is obtained for the MCG model in RS II brane, and it is concluded that our model is perfectly consistent with the union2 sample data.