A. Bagubali

Bio: A. Bagubali is an academic researcher from VIT University. The author has contributed to research in topics: Cognitive radio & Wireless. The author has an hindex of 4, co-authored 21 publications receiving 64 citations.

V2V Wireless Communication Protocol for Rear-end Collision Avoidance on Highways with Stringent Propagation Delay

Abstract: More than 23% of annual vehicle accidents are rear-end collisions, this gives an important test-case for enhanced collision avoidance approaches based on v2v wireless communications. V2V wireless network concern with the impact of a IEEE 802.11 based multi-hop MAC protocol that propagates an emergency warning message (EWM) down a platoon of cars on a highway. The design objective is to ensure reception of this message with stringent delay constraints so as to provide drivers with requisite available manoeuvre time (AMT) to avoid rear-end collision. This V2V wireless communication protocol provides a realistic simulation in Ns-2 for various topologies (lane-1& lane-3) and the performances were evaluated for different parameters such as EWM delay, delay due to overhead packets and probability of successful delivery of the emergency warning message (EWM).

Cognitive Radio: Spectrum Sensing Problems in Signal Processing

Abstract: electromagnetic radio spectrum is a natural resource. Effective Utilization of this natural resource is a Challenging task in Present Day Wireless Communication. Cognitive Radio is an emerging trend in wireless communication to Combat for spectral scarcity. Cognitive radio is an intelligent wireless communication system that is aware of its surrounding environment and uses the methodology of learning, and understanding from the environment and adapting to it. Advanced signal processing techniques are used in Cognitive Radio Network to achieve this intelligence. Spectrum Sensing is one of such a signal processing to identify spectrum holes which can be temporarily used without interfering Primary User. Every cognitive radio receiver is incorporated with Spectrum Sensing. There are various existing techniques to detect the spectrum of which some widely used are presented in this thesis.

Performance Analysis of Handover Schemes in Heterogeneous Networks

Abstract: Internet protocol (IP)-based mobile systems are ushering new and faster technologies in wireless mobile networking. Therefore, the expectations from these network services with respect to data transfer rate and quality of service (QoS) are high. As such, meeting these requirements is the recent trend in modern wireless technologies. An important aspect regarding such improvements is the modification of handoff schemes between different networks. In this paper, we are focusing on the recent trends based on seamless handoff scheme in heterogeneous networks such as worldwide interoperability for microwave access (WiMAX) and long term evolution (LTE). The development of the session initiation protocol (SIP) Prior-INVITE scheme is an improvement on the earlier used SIP Re-INVITE method, which comes a long way in decreasing the average handoff delay. The performance analysis using software simulation on account of various parameters, such as handoff delay, cost of signaling and packet loss rate are accomplished...

Smart watering of plants

Abstract: There are many devices in India which are used with man power (manual) that is they are operated with physical presence of a human being. They will not measure the water content of the soil and the required temperature to know if the soil actually needs watering or not.The main two aspects that we should consider in manual watering that I mentioned above. System of smart watering of plants is created For lessening manual work. By putting this system in your field or farm you not only save water but make your plants be the most effective they could be. Sprinklers or drip emitters or both can be used for making a effective system for all plants in any farm or field. Improper watering of fields which is a direct cause for the damage of plant health. A simple automatic plant watering system will do the job. In this project we use Arduino and soil moisture sensor with help of both we water the plants without physical presence. Our project’s main focus is on efficient water and power supply watering device.The project depends on a straightforward thought of dampness or moisture of soil. The Arduino based system is modified to detect dampness dimension of plants at specific occurrence of time, if the moisture content is not exactly determined which is the required water substance and as indicated by it the ideal measure of water provided till it achieves edge. This idea is to plan and grow minimal cost system which depends on embedded system for water irrigation system framework. This system utilizes soil moisture sensor to identify the water amount present in soil. The project utilizes Arduino Uno which is a controller to process the data.

Performance analysis of IMS based LTE and WIMAX integration architectures

Abstract: In the current networking field many research works are going on regarding the integration of different wireless technologies, with the aim of providing uninterrupted connectivity to the user anywhere, with high data rates due to increased demand. However, the number of objects like smart devices, industrial machines, smart homes, connected by wireless interface is dramatically increasing due to the evolution of cloud computing and internet of things technology. This Paper begins with the challenges involved in such integrations and then explains the role of different couplings and different architectures. This paper also gives further improvement in the LTE and Wimax integration architectures to provide seamless vertical handover and flexible quality of service for supporting voice, video, multimedia services over IP network and mobility management with the help of IMS networks. Evaluation of various parameters like handover delay, cost of signalling, packet loss,, is done and the performance of the interworking architecture is analysed from the simulation results. Finally, it concludes that the cross layer scenario is better than the non cross layer scenario.

Energy Detection Technique for Spectrum Sensing in Cognitive Radio: A Survey

Abstract: Spectrum sensing is the basic and essential mechanisms of Cognitive Radio (CR) to find the unused spectrum. This paper presents an overview of CR architecture, discusses the characteristics and benefits of a CR. Energy detectionbased spectrum sensing has beenproposed and used widely because it doesn’t require transmitted signal properties, channel information, or even the type of modulation. In this paper, a surveyof energy detector over Additive White Gaussian Noise (AWGN), different fading channels for spectrum sensing methodologies in cognitive radio is presented.Theoretical analysis of time domain energy detection and threshold setting is investigated. Cooperative spectrum sensing and a multiple antenna processing based energy detector receptions are also discussed.

A fuzzy aid rear-end collision warning/avoidance system

Abstract: Highlights? We have implemented a rear-end collision warning/avoidance system in a real car. ? The system decides how to perform the maneuver without leaving the road. ? A vehicle-to-infrastructure communication system is used to exchange data. ? Fuzzy logic is used both for the warning and for the avoidance systems. ? Experiments with real cars were conducted with propper results. To decrease traffic accidents is a declared target of Intelligent Transportation Systems (ITS). Among them, rear-end collisions are one of the most common and constitute one of the as yet unsolved topics in the automotive sector. This paper presents an approach to the avoidance of rear-end collisions in congested traffic situations. To this end, two fuzzy controllers, a Collision Warning System (CWS) and a Collision Avoidance System (CAS), have been developed. The former is in charge of alerting the driver in case of an impending rear-end collision to prevent or mitigate the crash. The latter is in charge of generating an output control signal for the steering wheel in order to avoid the collision. Both CWS and CAS have been tested with real cars using vehicle-to-infrastructure (V2I) communications to acquire data of vehicles. A system installed in the infrastructure capable of assessing road traffic conditions in real time is responsible for transmitting the data of the vehicles in the surrounding area. The systems have been tested at the Center for Automation and Robotics (CAR)'s facilities with two mass-produced cars.

A vehicle-density-based forwarding scheme for emergency message broadcasts in VANETs

Abstract: With the extension of wireless technology, vehicular ad hoc networks (VANETs) provide general data transmission services and emergency warning services. To rescue more drivers from being involved in an emergency event on the road, fast emergency message propagation is an important issue in VANET studies. There are two types of multi-hop broadcasting forwarder selection schemes for emergency broadcasting, known as sender-oriented schemes and receiver-oriented schemes. The sender-oriented schemes periodically maintain neighbor information in order to choose the best forwarder before broadcasting the message, while the receiver-oriented schemes distributed elect the forwarders. In this paper, we propose a vehicle-density-based emergency broadcast (VDEB) scheme to solve the problem of high overhead in sender-oriented schemes, and long delay in receiver-oriented schemes. The simulation results show that our VDEB scheme can achieve better performance with low delay and little overhead.