|Research Work||“Optical Soliton transmission system”|
|Faculty||Dr. Manoj Kumar, Professor & Principal|
|Status:||Executed Major Research Activities:|
The term soliton (formed from Latin solitarius – solitary) is one of the fundamental unifying ideas in modern theoretical physics and mathematics. An impressive practical implementation of the soliton concept has been achieved in fiber optics, where soliton pulses are used as the information carriers to transmit digital signals over long-haul. Optical soliton research, full of innovative spirit, has recently arrived at the stage of a first real-world implementation of the soliton concept in communication systems. Realization of soliton-based transmission will clearly demonstrate how the results of the fundamental soliton theory can be successfully exploited in very important practical applications.
Practical and research interest is directed mostly towards two main goals: development of effective high capacity long-haul transmission systems and the upgrade of existing terrestrial fiber networks. There are two principal approaches to overcome these limitations: in the first (that can be called “linear”) both the chromatic dispersion and nonlinearity are considered to be detrimental factors while in the second, the nonlinear and dispersive effects are counter balanced (such systems can be called “nonlinear”). Nonlinear effects that are detrimental in the “linear” systems can be used to improve transmission characteristics of optical communication systems.
- Our investigations have been focused to suggest alternative optical soliton based designs that are suitable for already installed optical transmission links. Based on our investigations, it is recommended that one of the promising ways to upgrade installed optical network is to exploit the 1.3μm optical window, where the step-index fibers have their zero dispersion wavelength, using wide-bandwidth polarization-insensitive SOAs. The pattern effect and the impact of chirp on pulse propagation after amplification have been investigated. The observations are based on modeling and simulation optical soliton transmission link. Optical soliton pulse transmission over distances of the order of several hundreds of kilometers has been shown with and without initial chirp.
- We investigated that the Kerr non-linearity stabilizes solitons against splitting due to birefringence. The birefringence induced time delay between X and Y polarization components reduces to 200 ps from 440 ps when the Kerr non-linearity is taken into account at polarization angle and fiber length of 631.72 km (10 soliton periods) & 1264.344 km (20 soliton periods) for both the linear and nonlinear soliton transmission.
- Our research goal was to realize long-haul, large capacity optical transmission by taking advantage of optical nonlinear effects, including optical solitons and nonlinear techniques for generating ultra short optical pulses. The soliton is a wave that exists in nature that can propagate over long distances without any distortion of its waveform. We have developed several novel path-averaged long-haul soliton transmission techniques, such as the use of path averaged soliton, dispersion-managed (DM) soliton, loss-managed soliton transmission systems. By adopting these techniques, we can increase the transmission capacity and upgrade installed terrestrial or submarine cables The investigations demonstrate the robustness of path-averaged soliton in a long-haul transmission link of 17,000 km at a bit rate of 10 Gbps. It has been investigated that relatively stable pulses can propagate over longer distances in long-haul dispersion managed soliton regime in a fiber link with loss and periodic amplification by keeping the average dispersion small but non-zero. It has been shown that the dispersion management is achieved through soliton pulse narrowing in anomalous dispersion fiber and broadening at DCF. In conclusion, we have reported that the pulse propagation in dispersion-managed soliton transmission link is similar to conventional transform-limited soliton transmission link.
- We have also carried out performance evaluation of the Optical Soliton Transmission Systems under the influence of various linear and non-linear fiber parameters & performance measures. Performance evaluation has been carried out for the different modulation formats viz. NRZ, RZ Soliton, RZ Raised Cosine and RZ Super Gaussian.
Simulations for data formats Return to Zero (RZ), Non Return to Zero (NRZ), RZSoliton, Duobinary and their subcategories has been done with and without ideal dispersion compensation for optical communication systems. The results show that in general dispersion compensation improves timing jitter. RZ-Rectangular pulses show the smallest value of jitter without compensation. It has been observed that the RZRaised cosine and Soliton gives minimum jitter after ideal compensation. It has been reported that the BER performance of optical communication system using duobinary data format is 10e-8 and 10e-37 before and after dispersion compensation respectively.
Further the comparative study show that the timing jitter is lowest in case of RZSoliton (0.0127 ns) after dispersion compensation and 0.0135 ns for RZ-Rectangular data format before dispersion compensation.
|Research Work||“Designing of Electromagnetic Applicators for Cancer Therapy”|
|Faculty||Dr. Neeru Malhotra, Associate Professor & Head|
Cancer has become one of the most devastating diseases in the world.
The interactions between the electromagnetic fields and biological systems have been the subject of great interest among the researchers for the last twenty years. In this area of research the use of microwaves energy in therapeutic medicine is a sensitive topic and has been in great demand over the years. Though the thermal therapies were being utilized for many diseases including the cancer treatment from early eighties, the hyperthermia technique is superseding other heat treatment modalities on account of its efficacy in association with radiotherapy and chemotherapy. Based upon the limitations of earlier antenna designs for microwave hyperthermia such as thermal lesion size, detrimental backwards heating, control of lesion generation and transient behaviour of tissue physical properties, the present research work focuses on simulation based design of interstitial and non- interstitial microwave antennas for the treatment of hyperthermia.
Electromagnetic fields predominantly have very positive properties for therapeutic applications including diathermy, hyperthermia for tumor and cancer therapy, liver ablation and cardiac ablation. The basic idea behind the hyperthermia treatment is to expose the body tissue at temperature 41-45ºC, killing the malignant cell and damaging proteins and structures within cell which may lead to shrink tumors. Microwave applicator suitable for hyperthermia needs to be properly designed in order to deliver electromagnetic energy into the tumor tissue with minimal irradiation of healthy tissue.
Microwave hyperthermia is recently being known to be in the interest of both, clinical and research oncologists, because of its properties to directly produce permanent damages of the treated tumors and to elicit important immunological responses against cancer cells by changing their immunogenicity. Hyperthermia is almost always used with other forms of cancer therapy such as radiation and/or chemotherapy and as an ablative procedure, according to the type of applicator used. Research has shown that high temperatures can damage and kill cancer cells, usually with minimal injury to normal tissues. According to the type of cancer tumor, the treatment technique is categorized as invasive or non-invasive. External hyperthermia is used to treat tumors that are in or just below the skin (superficial), where non-invasive applicators are located around or near the appropriate region, and energy is focused in the tumor to increase its temperature. For deep seated tumors internal or interstitial hyperthermia is applied using invasive applicators.
In this research work it has been discussed how advanced electromagnetic numerical techniques can be utilized to design the interstitial and non-interstitial antennas for realistic human body environment. To characterize and design antennas for the human body for microwave hyperthermia finite difference frequency domain (FDTD) and finite element method (FEM) have been proven to be powerful tools for calculation of electric, magnetic and thermal fields. The present work focuses to introduce the possibility of treatment planning and feasibility study for microwave hyperthermia.
Hyperthermia is a very effective way to improve cancer treatment, but it is to a large extent an experimental technique at this time. It needs special equipment, an efficient doctor and treatment team who are adroit in using it. Therefore, it’s offered in only a few cancer treatment centers in the US and Europe so far.
High temperature hyperthermia used to treat liver cancer, the effectiveness of which depends on highly localized spherical shaped leison with minimum back radiations near the tumor cells. The single slot coaxial antenna operating at 2.45 GHz in the ISM (Industrial, Scientific, and Medical) band is designed through 3D simulation for more realistic liver tissue using FEM based HFSS software. The field distributions and specific absorption rate (SAR) obtained for the antenna are exported to ANSYS software for determining temperature distribution in the liver tissue.
HFSS is a high-performance full-wave electromagnetic (EM) field simulator for arbitrary 3D volumetric passive device modeling that integrates simulation, visualization, solid modeling, and automation in an easy-to-learn environment where solutions to 3D EM problems are quickly and accurately obtained.
HFSS utilizes automatic adaptive mesh generation and refinement where hierarchical basis functions with mixed order h-p refinement automatically distribute element order based on element size and generate an optimum combination of hierarchical basis functions. After investigating the electromagnetic fields induced by microwave radiative antenna, the distribution of thermal field and SAR of invasive coaxial-slot antenna are obtained and analyzed for optimized performance. The results show that much spherical leison is obtained with the optimized coaxial slot antenna design facilitated by 3D modeling using HFSS.
|Research Work||“Performance Analysis of Data Formats in Optical Soliton Transmission Link under the impact of Chirp and Third Order Dispersion”|
|Faculty||Dr. Jagjit Singh Malhotra, Associate Professor|
This research work is focused on the Performance Analysis of NRZ, RZ, CRZ and CSRZ data formats in Optical Soliton Transmission Link under the impact of Chirp and Third Order Dispersion. The objective is to analyze the performance of these data formats using performance metrics viz BER, Q factor, Eye opening etc. The results obtained so far indicate that performance of CRZ and CSRZ under the given system is better as compared to NRZ and RZ data formats. However CSRZ has yielded so far best results.
|Research Work||“Blocking Artifact Detection and Reduction in JPEG Compressed Images”|
|Faculty||Dr. Jagroop Singh , Associate Professor|
The compression of digital images has received wide attention of researchers since it reduces the memory, bandwidth and transmission requirements. However, the reconstructed images suffer from visually annoying blocking artifacts at high compression ratios. As a result, image quality is subjectively rated down. In order to improve the quality of the reconstructed images, thus there is an obvious need for detection and removal of these blocking artifacts.
To reduce the blocking artifacts without degradation of image details, the proposed algorithm uses signal adaptive filtering as well as a corner outlier detection and replacement scheme. The signal adaptive filtering is based on four filtering modes in terms of activity across the block boundaries. To demonstrate the performance of the proposed novel algorithm-IIIR, PSNR, SSIM index based on HVS perception and other indices SF, BBM and MOS have been used. It is found that there is a significant improvement in the perceptual quality of the JPEG compressed images after the removal of blocking artifacts by the proposed method. Due to the low computational requirement, this method can be integrated into real time image/video applications that process image/video in the DCT domain, for online quality monitoring. The proposed method is especially suitable for applications involving image/video processing in DCT-domain.
|Research Work||Cross layer protocol design in wireless sensor network|
|Faculty||Ms. Bindiya Jain, Assistant Professor|
|Status:||Research in Process|
Energy efficiency is a major consideration while designing wireless sensor network nodes. Most sensor network applications require energy autonomy for the complete lifetime of the node, which may span up to several years. These energy constraints require that the system be built such that wireless sensor networks use battery-operated computing and sensing devices. Keeping in view these approaches our aim is to design energy efficient cross layer approaches in WSN. Secondly, we have designed a new protocol in MAC layer named AMST-MAC: Adaptive Sleeping Multi-Frames Selective Data Transmission Control for Wireless Sensor Networks. This protocol has objective to remove the redundancy, reduce the number of packets sent for same amount of information, and also to allow the node to sleep for the time when it is idle even in the data cycle.
|Research Work||Image Compression|
|Faculty||Ms. Aarti Kochhar, Assistant Professor|
Image compression has played a very important role for several applications in the area of multimedia communications, the objective being reduction of storage and transmission costs while maintaining the Image Quality. High quality image communication with low bit rate is gaining special importance in applications like video conferencing, video phone and interactive TV and newer applications like telemedicine, picture archiving and communication systems (PACS). Many effective coding techniques have been developed for various applications. The block discrete cosine transform (BDCT) is amongst the most widely used techniques for compression of still and moving images. The main drawback of BDCT based compression techniques is the introduction of blocking artifacts which represents the artificial discontinuity between adjacent blocks resulting from the independent processing of the blocks without taking into account the inter-block pixel correlations. There is an obvious need of removing these blocking artifacts in the low bit rate transform compressed images. Several techniques/algorithms have been proposed by researchers, both in frequency and spatial domains, for reduction of these artifacts with varied degree of success. I also did work to cope with the blockiness problem. For smooth regions, the blockiness artifacts is removed by modifying the DCT coefficients in the first row. For texture and edge regions, an edge preserving 3×3 median filter is used. The post processing algorithm reduces these blocking artifacts efficiently. The reduction in the blocking artifacts for each image have been evaluated different indices.
|Research Work||“Wireless Network Selection Algorithm for Multimedia Services in Heterogeneous Environment”|
|Faculty||Dr. Kiran Ahuja, Assistant Professor|
A heterogeneous wireless environment integrates several different wireless access technologies; each with different characteristics, in order to satisfy the needs and the requirements of the mobile users. However, in such a diverse environment, the requirement for ubiquitous service delivery is usually equivalent with the Always Best Connected problem, i.e., the selection of the access technology that best suits the needs of the users. It is a significant issue to have mechanisms to help each user to decide which network is the most suitable for him/her at each moment of time for every application that the user requires. The decision is based on several QoS parameters criteria that ought to be optimized and this makes the network selection algorithm a very difficult task. The research is focused on network selection schemes for multi-service heterogeneous wireless networks. Depending on the information availability for the decision making from the underlying wireless technologies, profiles of users as well as networks are customized accordingly. The proposed network selection methods incorporate the use of parameterized network and user profiles in order to model diverse QoS flexibility for different real-time and non-real-time applications.
|Research Work||“Design and development of a cross layer frame work for wireless sensor networks”|
|Faculty||Mr. Ramneek Sngh, Assistant Professor|
|Status:||Research in Process|
The research works aims to develop a cross layer framework for improving the various QoS parameters for wireless sensor networks. The methodology is to modify the conventional TCP/IP protocol stack to achieve the best possible interactions between various layers and optimize the network parameters. Simulation will be done using NS2 simulator.
|Research Work||“Synthesis & Characterisation of Microwave Materials”|
|Faculty||Mr. Amit Arora, Assistant Professor|
|Status:||Research in Process|
With the development of radar and microwave communications technology, there is a need for the anti-electromagnetic interference devices and to minimize electromagnetic reflection from large structures such as aircrafts, ships& tanks (Stealth technology). The electromagnetic wave absorbing materials with the capability of absorbing unwanted electromagnetic signals have become one of the most crucial high-tech materials in recent years. So in my research work, such microwave materials will be developed which can be used in microwave applications and devices.
|Research Work||“Convergence of Optical and Wireless Networks”|
|Faculty||Mr. Love Kumar, Assistant Professor|
|Status:||Research in Process|
Network convergence is the productive conjunction of phone, video and information correspondence inside a solitary system. The utilization of numerous correspondence modes in a solitary system offers comfort and adaptability unrealistic with discrete frameworks. System merging alludes to the procurement of phone, video and information correspondence administrations inside a solitary system. As it were, one funnel is utilized to convey all types of correspondence administrations. The procedure of Network Convergence is fundamentally determined by improvement of innovation and interest. One primary objective of such joining is to convey better administrations and lower costs to shoppers. System meeting in the US is encouraged by the legitimate and administrative structure set up by Congress and the Federal Communications Commission (FCC) and driven by new eras of telecom innovation. Not at all like different nations (e.g., Japan, South Korea, China) or locales (e.g., the European Union), the U.S. never embraced a formal meeting arrangement. Innovative change is driving merging from already unmistakable information transfers and media markets. The U.S. correspondences base is developing from circuit-based network, in which singular applications are firmly woven into the system design, to Internet Protocol system, in which different applications ride on top of the physical system layer.
|Research Work||Image Restoration|
|Faculty||Ms. Poonam Sethi, Assistant Professor|
Images are produced to record or display useful information. Due to imperfections or degradations in the imaging and capturing process, however, the recorded image invariably represents a degraded version of the original scene. The undoing of these imperfections is crucial to many of the subsequent image processing tasks. Degradations can occur in the entire process of image acquisition, and there are many different sources of degradation. For instance, in aerial reconnaissance, astronomy, and remote sensing, images are often degraded by atmospheric turbulence, aberrations of the optical system, or relative motion between the camera and the object. Image degradations can be classified into several categories, among which point degradations or noise and spatial degradations or blurring are most common in applications. Other types of degradations involve chromatic or temporal effects.
Blurring is a form of bandwidth reduction of an ideal image owing to the imperfect image formation process. It can be caused by relative motion between the camera and the original scene, or by an optical system that is out of focus. In addition to these blurring effects, noise always corrupts any recorded image. Noise may be introduced by the medium through which the image is created (random absorption or scatter effects), by the recording medium (sensor noise), by measurement errors due to the limited accuracy of the recording system, and by quantization of the data for digital storage. The field of image restoration sometimes referred to as image deblurring or image deconvolution is concerned with the reconstruction or estimation of the uncorrupted image from a blurred and noisy one. Essentially, it tries to perform an operation on the image that is the inverse of the imperfections in the image formation system. In the use of image restoration methods, the characteristics of the degrading system and the noise are assumed to be known a priori. In practical situations, however, one may not be able to obtain this information directly from the image formation process. The goal of blur identification is to estimate the attributes of the imperfect imaging system from the observed degraded image itself prior to the restoration process. The combination of image restoration and blur identification is often referred to as blind image deconvolution. Most image restoration methods are based on convolution applied globally to the whole image.
|Research Work||“Human-Computer Interaction”|
|Faculty||Mr. Hari Singh, Assistant Professor|
|Status:||Research in Process|
The human-computer interface (HCI) is a point where the human can tell the computer what to do and the computer displays the requested information. Like any communication and control system, an HCI has an input, an output and a translational algorithm that converts the former to the later. HCI output can be cursor movement, letter or icon selection, or another form of device control, and provides the feedback that the user and the HCI can use to adapt so as to optimize communication. Human-computer interaction is a discipline concerned with the design, evaluation and implementation of interactive computing systems for human use and with the study of major phenomena surrounding them. The most obvious application of HCI technology in its present state of development is to patients suffering from Amyotrophic lateral sclerosis (ALS). ALS is a neuro- degenerative disease that leads to progressive paralysis of voluntary muscles. Patients eventually lose their ability to move or speak, but retain the ability to move their eyes. Therefore, eye movement is the most natural way for late-stage ALS patients to communicate. Due to the advanced performance of current computers and cheap price of external equipments, it is easy to construct a Human Computer Interface (HCI) as per the requirement of a patient. Therefore, this research is oriented to development of an eye based human-computer interaction system for ALS patients.
|Research Work||Performance Investigations of STBC-OFDM Systems under Wireless Fading Channels|
|Faculty||Mr. Ganesh Chand, Assistant Professor|
|Status:||Research in Process|
ORTHOGONAL frequency division multiplexing (OFDM) has been widely applied in wireless communication systems in recent years due to its capability of high-rate transmission and low-complexity implementation over frequency-selective fading channels. Space-time coding is another promising technique to provide diversity gain through the use of multiple transmit antennas, especially when receive diversity is too expensive to deploy. In particular, the space-time block code (STBC) has received a lot of attention because a simple linear decoder can be used at the receiver side. These advantages make OFDM combined with STBC, known as STBC/OFDM systems. The advantages of orthogonal codes are that they do not require channel knowledge at the transmitter, and simple linear processing can be employed at the receiver for the symbol recovery. These orthogonal designs guarantee the inter-symbol interference (ISI) free condition when the communication channel is flat fading. In this work we will exploit the properties of cyclic prefix in order to cancel ISI for clipped OFDM systems. By using the properties of cyclic prefix a channel estimation technique is to be developed for the proposed system.
|Research Work||Investigation of SCm-CATV system with & without FBG|
|Faculty||Mr. Ashish Malhotra, Assistant Professor|
In the information age, we are seeing a relentless demand for networks of higher capacities at lower costs. Concepts for broadband systems have been discussed since a long time however, recently through buzzwords such as “internet”, “communication highway” and “multimedia”, the discussion about interactive broadband services, especially those for residential customers has been so accelerated worldwide that the society has become an information society. New approaches have been attempted for further development of broadband distribution services and applications. Creation of a SCM-CATV link is the key step that will enable computer-mediated communications. It is a desirable alternative to the current fragile and bandwidth-limited Internet. It sidesteps the slow response of the telecommunications industry to data communications needs. The inetrnet growth is creating a significant strain on the voice telecom infrastructure. This problem is likely to be exacerbated further by the high bandwidth access required by NetPCs and multi-media applications such as Videophone and Video Email. Other broadband applications of interest include entertainment-on-demand, many-to-many conferencing (and collaboration), telemedicine, and distance learning.
Technology will soon allow us to build an independent National Data Grid of 100-gigabit bandwidth. This would be over 100 times faster than most current Internet backbone links. It has the potential to expand to 100 Terabits by the year 2010. It is the only way to provide gigabit data rates to individual subscribers at affordable rates in the foreseeable future. The SCM CATV initiative is primarily intended for power users who are chafing at the current limitations and high costs of receiving high bandwidth data from the current telecom providers. However, it should be obvious to everyone that these power users will immediately start using the digital system for video telephony and entertainment delivered on an individualized basis. permanently changing the index of refraction in a periodic pattern along the core of the fiber
|Research Work||Feature Analysis & Feature Classification of Neural Activity for Human Computer Interaction|
|Faculty||Mr. Navleen Singh Rekhi, Assistant Professor|
|Status:||Research in Process|
The signal and image processing explores issues related to modeling, developing and evaluating algorithm to extract the information from the concerned source, such that to implement the findings on electrical and electronic systems. The specific research areas include robotic vision, neural prosthesis, speech and radar processing. Based on these applications, I had done work in neural prosthesis under the MHRD project. The work was based on developing the prosthetic hand for an individual with specific disability. The research had been published in leading IEEE conferences and journals. In continuation to processing, I have extended my work to robotic vision based on image processing. Human vision Perception is the ability to understand the information from the surroundings contained in the visible light. One of the major concern, is to identify what information is required to distinguish the objects from the background. Hence, the primary objective of my research will be to design and implement a new algorithm for better visibility and brightness of the image quality.
|Research Work||VLSI Design & MEMS|
|Faculty||Ms. Risha Sharma, Assistant Professor|
My Research discusses applications of semistate theory in VLSI Design. Semistate theory is applied to design of linear VLSI circuits using an admittance framework for which the main components are CMOS capacitors, differential pairs and current mirrors. It shows how the hysteresis behaviour in electronic circuits can be explained in a robust manner using T Spice simulations and MATLAB. Furthermore, PFSCL circuit for nonlinear characteristic shaping and also this circuit is used to produce hysteresis loops with energy dissipation in circuit and noise margin.
The relation of noise margin and voltage swing, EDP with and without hysteresis is well explained in it with comparing the simulated and analytical results and error in noise margin, voltage swing and EDP of analytical results with simulated results.
Semistate theory also give results with consuming less time as compare to other methods and also gives various parameters simultaneously and it also gives information about hysteresis as compare to other methods. By using semistate theory, the error between simulated and analytical results becomes so less as compare to previous method used and various results validates with previous work.
My recent research is related to non-classical (generalized) theory of thermoelasticity. The analytical expressions for thermoelastic damping and frequency shift of vibration due to thermal variations areobtained. It is noticed that the damping of vibrations and frequency shift significantly dependon thermal relaxation time in addition to thermomechanical coupling in a circular plate underresonance conditions. The vibrations of such resonators are also significantly affected due tosurface conditions. The expressions for displacement and temperature fields in the plateresonator are also derived and obtained. The lower and upper bounds for thermoelastic damping have also been obtained. Some numerical results have been presented for illustration of analytical developments in case of silicon material plate.