Gurjit Kaur

Design and analysis of VCSEL LASER for third window of optical communication system

The acronym VCSEL stands for Vertical Cavity Surface Emitting Lasers. In this paper design, simulation and analysis of VCSEL at different wavelengths near the third transparent window i.e. 1550nm is presented. Comparative analysis is done for three wavelengths that are 1510nm, 1540nm, and 1580nm. The results suggest overshoots in voltage wavelength plots in 0-1 volts region. The analysis is helpful to identify the advantages and disadvantages of these wavelengths for different applications. Analysis also suggests the threshold voltage before which VCSEL deprives us any sort of output.

Modified Three-Dimensional Multicarrier Optical Prime Codes

We propose a mathematical model for novel three-dimensional multicarrier optical codes in terms of wavelength/time/space based on the prime sequence algorithm. The proposed model has been extensively simulated on MATLAB for prime numbers () to analyze the performance of code in terms of autocorrelation and cross-correlation. The simulated outcome resembles the mathematical model and gives better results over other methods available in the literature as far as autocorrelation and cross-correlation are concerned. The proposed 3D optical codes are more efficient in terms of cardinality, improved security, and providing quality of services.

Simulation and Analysis of Optimum Golomb Ruler Based 2D Codes for OCDMA System

The need for high speed communications networks has led the research communities and industry to develop reliable, scalable transatlantic and transpacific fiber-optic communication links. In this paper the optimum Golomb ruler based 2D OCDMA codes has been demonstrated. An OCDMA system based on the discussed 2D codes is designed and simulated on Optisystem. The encoder and decoder structure of OCDMA system have been designed using filter and time delays. Further the performance is analysed for various parameter such as bit rate, number of users, BER (Bit Error Rate), quality factor, eye diagram and signal diagram. The system is analyzed for up to 18 users at 1 Gbps and 1.25 Gbps bit rate.

Development of coded-cooperation based multi-relay system for cognitive radio using mathematical modeling and its performance analysis

Coded cooperation is a cooperative relaying technique which is bandwidth efficient and can provide better connectivity when used with cognitive radio. Earlier cognitive radio is implemented with cooperative schemes like decode and forward, amplify and forward, compress and forward, etc., which gives moderate spectrum efficiency and diversity with reduced fading problem of wireless communication. But these techniques are not bandwidth efficient so need huge bandwidth for transmission. In this paper, we have developed a mathematical model of new coded-cooperation based multi-relay system for cognitive radio and its outage probability is analytically derived for underlay mode. The performance analysis of proposed system is carried out in terms of interference temperature constraint, channel gain, number of relays through outage probability for single and multilink relays at the primary node for Rayleigh channel. The proposed system shows that the cognitive radio with coded cooperation outperforms the already existing techniques in terms of diversity, bandwidth, spectrum utilization efficiency and improve the communication quality. In addition, the theoretical analysis of the outage probability is validated by asymptotic analysis.

A Prototype of IoT-Based Real Time Smart Street Parking System for Smart Cities

Smart city is a vision that aims to integrate multiple information and communication solutions to residents with essential services like smart parking inside the all streets. Today, the parking systems has been changed by new advances that are empowering urban communities to diminish levels of congestions altogether. Internet of Things (IoT) is also new advancement which helps in detection of vehicle occupancy and congestion by basic intelligence and computational capability to make a smart parking system. The main motivation of using IoT for parking is to collect the data easily for free parking slots. This work presents the prototype of IoT-based Real Time smart street Parking System (IoT-based RTSSPS) with accessibility of data to make it simpler for residents and drivers to locate a free parking slot at the streets. Firstly, this work presents the introduction of IoT for smart parking with technology backgrounds, challenges of accessing IoT and database. Secondly, this work presents the prototype design of IoT-based RTSSPS with architecture and algorithm. IoT-based RTSSPS architecture is divided into three parts IoT-based WSN centric smart street parking module, IoT-based data centric smart street parking module and IoT-based cloud centric smart street parking module with street parking algorithm, evaluation and future directions.

Design of Cloud-Based Green IoT Architecture for Smart Cities

In the smart cities, objects can smartly communicate with the people through Internet of Things (IoT). It will make smart cities a greener place by detecting pollution through IoT and environmental sensors. In order to maintain the sustainability of green place in smart cities, the emerging technology, i.e. Green IoT automatically and intelligently makes smart cities sustainable in a collaborative manner. Governments and a lot of organizations around the world are doing a lot of efforts to campaign the importance of the reduction of energy consumption and carbon production as well as emphasize on the Green IoT for smart cities. Various IoT related smart cities architectures are already presented in literature. But this work presents the concept of the “Green IoT” to create a green environment which will apprehend the idea of energy saving in smart cities. In this chapter, design of Green IoT architecture is proposed for smart cites with the focus to reduce energy consumption at each stage and ensure realization of IoT toward green. This proposed Green IoT architecture is based on the cloud based system which reduces the hardware consumption.

Design and Implementation of Electro-Optic 2×2 Switch and Optical Gates using MZI

Abstract MZI switches are well-known devices for high speed communication applications. A lot of researchers have designed MZI switches by using lithium niobate and potassium niobate material. But the major problem of using these type of material includes high insertion losses and required high switching voltage. So, in this research paper we have designed a 2×2 electro-optic switch using optical waveguide designed with Titanium (Ti) diffused in Strontium barium niobate (SBNO3) material which can operate at wavelength of 1.3 um. Results show that the proposed structure gives better output in terms of extinction ratio (=29.9 db) as well as for insertion losses (≤0.018). Further, we have designed various optical gates i. e. XNOR, XOR and AND optical gates and their performance is also evaluated by varying electrode voltages. It is inferred from the results that the proposed model gives better results even in terms of output power which can be used for commercial purpose.

Design of an Improved Spectrum Sensing Technique Using Dynamic Double Thresholds for Cognitive Radio Networks

We, in this paper, introduce a spectrum sensing scheme utilizing two stages for spectrum detection and utilizing dynamic threshold. The first stage consisting of energy detection is followed by fuzzy logic based detector employing dynamic thresholds for final decision making of the spectrum sensing. Two metrics—Credibility_energy and Credibility_psd as inputs to the fuzzy logic detector are introduced. Numerical results show that the proposed scheme improves detection performance significantly as compared to existing two stage schemes at local node. The approach does not require a priori knowledge about the format of primary user signal retaining its practical implementation simple. We further investigate cooperative sensing with the proposed scheme to show that it outperforms the conventional cooperative spectrum sensing. An analytical expression for optimal number of CR users for cooperative spectrum sensing is also derived. This yields enhanced local sensing performance with reduced communication overheads. Having determined the optimal number of users, for cooperative spectrum sensing, the probability of error defined as the sum of probability of miss detection and probability of false is also minimized. Numerical results show that more enhanced local sensing performance reduces the number of optimal users for cooperation up to a significant extent at low SNR. Owing to the advantages of easy implementation, low cost and smaller overheads, the proposed solution offers a potential spectrum detection technique for cognitive radio systems.

Advances and improvements in VCSEL designing

In 50 years of research and development, VCSEL (Vertical-cavity surface-emitting lasers) photonics opened up number of applications in various fields. VCSEL being inexpensive, reliable, and readily manufacturable is one of the most compact laser light sources for generation of high intensity coherent light in - free space, optical fibers, board to board, on-chip optical interconnects, module to module and other information related system networks. This paper reviews the efficiency, thermal stability and temperature stability of VCSEL. Change in wavelength of VCSEL or VCSEL arrays is caused by changing the properties of periodic mirrors, cavity length and substrate material. Such changes enable us to manipulate the speed of light. Optical interconnects in data centers and supercomputers are the most attracting site of interest. VCSEL shows higher coupling efficiency into fibers due to having a circular beam cross section and a low output beam divergence angle. Due to high quality vertical light emission by the device, number of VCSEL lasers can be implemented on a single chip. A review of the potential of the device and the challenges faced in the functioning of VCSEL are also presented.

Performance analysis of Welch and Blackman Nuttall window for noise reduction of ECG

Electrocardiography (ECG) signal gives information about coronary heart disease based on electrophysiology of the heart. In a diagnostic analysis of biomedical signals such as ECG white noise is a major problem for extracting the features. The present work introduces the windowing technique to cope up with the white noise effects in the ECG signal. In this paper performance has been evaluated using Low pass filters with Finite Impulse Response (FIR) using windowing method such as Welch and Blackman Nuttall. The signals are taken from the MIT-BIH database which includes noisy and noise free waveforms. The work has been done in Lab View. The results assimilated for FIR filters with these two windows are analyzed by comparing the features and by distortion parameters of ECG waveform.