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Journal of Communication Engineering & Systems
Contents
1. Co-planar Waveguide Circular Ring Microstrip Patch Antenna for WLAN Applications Meenal Kate, Anjana Goen
1
2. A Study on Wireless Sensor Network Deployment and Lifetime Maximization of Wireless Sensor Nodes in Natural Gas Pipeline Monitoring System Md. Fahad Monir, Sarjo Das, Priyankar Roychowdhury
7
3. LIS Education Research in India K. Rajaram, S. Jeyachitra, S. Subha
17
4. Human Tracking and Positioning in Semi Outdoor Area using Ultra Sound Positioning System Saima Almas, Md. Humayun Kabir
23
5. Voice over Wi-Fi Employing SIP (Session Initiation Protocol) Shubham Chowdhry, Ravi Jaitly, Shrish Bajpai
32
Journal of Communication Engineering & Systems
ISSN: 2249-8613(online), ISSN: 2321-5151(print) Volume 6, Issue 3 www.stmjournals.com
Co-planar Waveguide Circular Ring Microstrip Patch Antenna for WLAN Applications Meenal Kate1,*, Anjana Goen2
Department of Electronics, Rustamji Institute of Technology, Tekanpur, Gwalior, Madhya Pradesh, India
Abstract
A printed circular microstrip patch antenna with a four rectangular shape strip and co planar rectangular ground plane has been proposed. Four rectangles of dimensions 4.8mm x3mm are arranged in such a manner to achieve both the WLAN frequency band. The bandwidths of 341MHz and 414MHz are achieved having a resonant frequency of 2.37GHz and 5.45GHz respectively. This antenna is printed on the glass epoxy (FR4 lossy) of dielectric substrate with relative permittivity (€r) of 4.3, thickness of 1.6 mm. Other parameters such as directivity, antenna gain, radiation pattern are also analysed with different values of ground plane length. The proposed antenna simulation result is capable of operating over the 2.187– 2.527 GHz frequency band and 5.234-5.643 GHz frequency band, which cover the 2.4/5.2GHz, WLAN operating bands. Keywords: Circular ring microstrip patch antenna (CRMPA), microstrip patch antenna (MPA), multiband antenna, wireless local area network (WLAN) Antenna
INTRODUCTION
The microstrip patch antennas (MPA) are the most widely used for the last few years due to their attractive features such as light weight, low volume, ease in fabrication and low cost. Some wireless communications applications of antennas are required to simultaneously operate for Wireless Local Area Network (WLAN) and Worldwide Interoperability for Microwave Access (Wi-MAX) technology. The specified spectrum for WLAN is centred at 2.4, 5.2, and 5.8 GHz, and for Wi-MAX at 2.5, 3.5, and 5.5 GHz [1]. A huge number of studies have been done in the area of printed microstrip antennas. This includes different shapes and structures, for example, rectangular patch having dual broad band characteristic was reported in [2]. An antenna system composed of a combination of several transmission lines and multi ports has been proposed in [3]. In recent years, several reports have appeared about the development of low-profile multiband antennas. However, most of them are relatively large and/or do not provide
desired bandwidths. One method of improving the bandwidth and reducing the size is to use a planar microstrip antenna with slots and strips on the patch and ground plane. Among different shapes of radiating patches such as square, rectangular, circular, ellipse etc. the rectangular radiating patch and circular radiating patch was found to exhibit good radiation characteristics, simple to design and compact in size when compared to other microstrip patch shapes [4] and CPW-fed technique [5] is used for transmission line, i.e. transmitting or receiving the electromagnetic (EM) waves. In this paper, circular MPA with feeding line and a co planar ground plane is presented which is actually a single band antenna in the WLAN frequency band. The proposed printed MPA is a simple configuration fed by 50 ohm SMA connector [6] placed under a ground plane of the antenna. The properties of the antenna such as return loss, radiation patterns, directivity and gain are determined via a simulation process using CST (Computer Simulation Technology) Microwave Studio
JoCES (2016) 1-6 © STM Journals 2016. All Rights Reserved
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Journal of Communication Engineering & Systems
ISSN: 2249-8613(online), ISSN: 2321-5151(print) Volume 6, Issue 3 www.stmjournals.com
A Study on Wireless Sensor Network Deployment and Lifetime Maximization of Wireless Sensor Nodes in Natural Gas Pipeline Monitoring System 1
Md. Fahad Monir1, Sarjo Das1,*, Priyankar Roychowdhury2
School of Information and Communication Technology, KTH Royal Institute of Technology, Stockholm, Sweden 2 Department of Electrical and Computer Engineering, The George Washington University, Washington, DC, USA
Abstract
Leakage in Natural Gas Pipeline is a very common problem that may lead to economic losses, environmental hazards and pollution. Therefore, the maintenance and security monitoring of the natural gas pipeline has remained a big concern for many years. In the recent times, implementation of Wireless Sensor Networks (WSNs) has become very popular. This is due to the low cost and sustainability of WSNs. Since, the implementation of WSNs in different applications has increased rapidly; the energy consumption of WSN’s has also become an important part of study as nodes are powered by battery. In this paper, an architectural model of WSN implementation will be presented. This model can be used for identifying the leakage or other kind of damage monitoring in gas/oil pipelines as well as a process of lifetime maximization of the operating nodes. Moreover, we have studied the effectiveness of equal distance placement scheme, based on Ideal power model and Tmote power model, for WSN’s lifetime maximization in gas pipeline monitoring system. Keywords: Wireless sensor networks, gas pipeline monitoring, WSN application, linear sensor placement, lifetime maximization
INTRODUCTION
Natural Gas is a type of fossil fuel that is used extensively to generate energy. As the demand of energy is increasing day by day, oil and natural gas producing countries are ramping their production and building up infrastructures. Based on the reference case of International Energy Outlook 2016 (IEO, 2016), the consumption of natural gas increases by 1.7% per year in average for industrial use and 2.2% per year in electric production. It has been projected that the total worldwide consumption of natural gas will be increased by approximately 95 trillion cubic feet (Tcf) in a time frame of 2012–2040. As a result, natural gas producers, through the worldwide, increase their production and the supplies is predicted to be raised by 69% by 2040 (as shown in Figures 1 and 2) [1]. Natural gas production industries always seek for a safe, economical and stable infrastructure
for their industries. An important component of this infrastructure is oil/gas pipelines. There is a need for a system that can monitor the gas pipeline 24*7 for security purpose and to detect any accidental leakages [2]. This system can be implemented, using Wireless Sensor Network that will help to prevent wastage of precious resources and will allow uninterrupted flow of gas through the pipeline. WSNs have already been used for many useful applications. For example, WSNs have already achieved a great success in natural gas pipeline monitoring systems [3–5]. Because of their inherent and other advantages, Wireless Sensor Nodes have been deployed for environmental monitoring applications especially in gas fields. Such a power efficient monitoring system will help a nation protect its assets and also help to prevent accidents or disasters and thus avoiding environmental pollution.
JoCES (2016) 7-16 © STM Journals 2016. All Rights Reserved
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Journal of Communication Engineering & Systems
ISSN: 2249-8613(online), ISSN: 2321-5151(print) Volume 6, Issue 3 www.stmjournals.com
LIS Education Research in India K. Rajaram1,*, S. Jeyachitra2, S. Subha3
1
Librarian, Department of Library and Information Science, K.S. Rangasamy Institute of Technology, Tiruchengode, Tamil Nadu, India 2 Librarian, Department of Library and Information Science, Urumu Dhanalakshmi College, Tiruchirappalli, Tamil Nadu, India 3 Librarian, Department of Library and Information Science, Sri Vasavi College, Erode, Coimbatore, India
Abstract
Libraries and Information Centres (LICs) play a vital role in the socio-economic development of a nation. The accelerated growth in research and developmental activities in sciences and technology and also in the fields of social sciences and humanities contributed to a phenomenal growth in the universe of subjects resulting in information explosion and interdisciplinary approach to research during the second half of the 20 th century. These developments generated new demands and pressures on the services offered by the libraries and information centres in our country and elsewhere. Keywords: LIS Research, Need, Quality, Observations
*Author for Correspondence E-mail: jairajaram6@gmail.com
INTRODUCTION
The rapid strides our country made in different spheres of human endeavor since independence and the efforts being made to sustain this progress and reach new heights added new dimensions to the services rendered by LICs. In order to meet these new challenges and find proper, suitable and sustainable solutions and to explore new areas, research has become sine-quo-non in the field of library and information science [1].
DEFINITIONS OF RESEARCH
There are numerous definitions we come across in the English language dictionaries, encyclopedias and other reference tools. But the definition obtained from the Webster’s Third New International Dictionary is very precise and throws more light on the essential qualities of research. It defined research as; “Studious inquiry or examination; especially critical and exhaustive investigation or experimentation, having for its aim the discovery of new facts and their correct interpretation, the revision of accepted conclusions, theories, or laws in the light of newly discovered facts, or practical application of new or revised conclusions, theories or laws’ [2].
In other words research is “The manipulation of things, concepts or symbols for the purpose of generalizing to extend, correct or verify knowledge, whether, that knowledge aid in the construction of a theory or in the practice of an art” [3]. In another view, research in any discipline is “Any systematic quest for knowledge that is characterized by disciplined inquiry. In the process of conducting research an investigator is concerned with three major activities: 1. The definition of terms, 2. The posing of questions or stating of proposition which incorporate the defined terms in an which incorporate the defined terms in an explanatory fashion, 3. The testing of propositions or search for answers to exploratory questions” [4].
NEED FOR RESEARCH IN LIS
Several factors have contributed the need for research in LIS. Briefly these are: 1. Changes in the information scenario in the country due to socio-economic and technological developments naturally necessitated a fresh look in to the discipline. 2. Research at advanced levels is very essential for the growth and development
JoCES (2016) 17-22 © STM Journals 2016. All Rights Reserved
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Journal of Communication Engineering & Systems
ISSN: 2249-8613(online), ISSN: 2321-5151(print) Volume 6, Issue 3 www.stmjournals.com
Human Tracking and Positioning in Semi Outdoor Area using Ultra Sound Positioning System Saima Almas*, Md. Humayun Kabir Department of Electrical and Electronics Engineering, American International University-Bangladesh, Bangladesh Abstract
In this thesis, we introduced the indoor and semi outdoor location determination problem. The localization accuracy metrics are the mean error per pixel and the room averaged mean error. We have tried to assess the accuracy of the algorithm, as the location and the number of BSs varies, path loss exponent n value changes. By measuring RSS and mean error of our proposed system, it is concluded that the number of BS must be greater than or at least seven. By calculating and measuring the average mean error of all pixels of our proposed system and reducing the value of AME by increasing BSs, we have made our system more efficient than other systems and we have deployed this technique in a semi outdoor environment instead of only indoor. Keywords: Human tracking, semi outdoor, ultra sound positioning system, average mean error, receive signal strength
INTRODUCTION
Nowadays human tracking and positioning has become very important issue especially for security purposes. This is the reason of doing this particular thesis. Positioning is the general term for determination of a position of an object or a person. Indoor localization is a system to locate objects or people inside building; and outdoor localization means localization in outside of a building. Semi outdoor localization locates objects or people in parking areas, parking area of factory, parking area of hospital, playground, garden area, pool area etc. Commonly used positioning systems are GPS, WLAN/Wi-Fi, ultra sound etc. Ultra sound positioning system uses ultrasound signal to measure position. Besides, ultrasound signals are used by bats to navigate in the night. Cricket location-support system provides efficient performance, robustness, user privacy, decentralized administration, network heterogeneity, low cost and fault tolerance for lacking in number of emitters and portion-ofa-room granularity though the receiver consumes more power [1]. A hybrid positioning approach by UWB radio communication systems for NLOS can be considered as well where SNR increases the pointing performance of FP methods though the computing process is very large and
complex [7]. This hybrid approach combines CIR based FP with an iterative-TOA real time positioning method and reduces the NLOS error effectively. An easier co-relation formula should be considered to point out the position easily [2]. A crowd-based approach for automatic collecting of indoor localization, FP provides short range approximation errors reduced to 1.3 m and FP estimation errors reduced to 0.5 m [3]. RFID-based indoor positioning technology provides simplicity to the system, low-cost, high portability, easy maintenance, capability of providing both identification and location, a long effective range (up to 1000 m for a single transmitter in free space), high penetration capabilities and flexibility in tag size though has one-way communication links, multipath effects and unstable RSS [4]. A brief overview of existing localization techniques and methods, including signal measurement methods, positioning algorithms, networking techniques and systems, is given which can be used for indoor human tracking [5].
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Journal of Communication Engineering & Systems
ISSN: 2249-8613(online), ISSN: 2321-5151(print) Volume 6, Issue 3 www.stmjournals.com
Voice over Wi-Fi Employing SIP (Session Initiation Protocol) Shubham Chowdhry*, Ravi Jaitly, Shrish Bajpai Department Electronics and Communication Engineering, Faculty of Engineering, Integral University, Lucknow, Uttar Pradesh, India Abstract
In the recent years, VoIP and SIP based calling has been emerging as a new innovation and a master technology in reducing all over cost of communication and secure calling among various MNCs and other management based calling centres. Voice over Wi-Fi (VoWi-Fi) emerged after voice over IP (VoIP) and manifests to be a useful technology. It acts as a substitute to usual coaxial cable phone system. The purpose of this research is to design and implement a telephony program that uses Wi-Fi in an end to end link or WLAN (Wireless Local Area Network) as a means of communication between mobile phones at zero cost. The breakthrough in VoWi-Fi may severely alter the cell phone business in the upcoming future due to its lower cost, flexibility and portability. We have briefly discussed on each aspect including, virtualization, SIP, CentOS, softphones and Wi-Fi which are very much engaged in designing the layout as well as in implementation of the idea behind this research. We have also given the future prospects of VoWiFi and its deployment in the various companies. Keywords: SIP, VoIP, IP phones-phones with logical IP address, Wi-Fi, virtualization
INTRODUCTION
Voice over wireless LAN (VoWLAN) is a practice of wireless broadband network specified under IEEE 802.11 standards for the objective of vocal conversation. The early stage during the initiation of work was electing Oracle VM virtual box as a hypervisor. A hypervisor or virtual machine monitor (VMM) is a component of computer software, firmware or hardware that is responsible for creating and running virtual machines. CentOS ver.7.2 is taken as an operating system and is installed within the virtual machine. A general purpose licensed (GPL) source code asterisk, is used as a source code that runs on the OS. After compilation process, the parameters (SIP end points (users), codec designation (ulaw, alaw, GSM), dialling pattern designs were configured. Finally, the source code as well as the virtual machine is provided with the common internet IP address line. The end users are linked up using a softphone and access same IP Address. As soon as the connections are made, calling is possible. Some of the biggest enterprises have successfully depreciated the overall communication cost using SIP based method
of communication. Cisco squares in San Jose and Research Triangle Park (RTP), replaced over a hundred PRI (23 channel) TDM trunks, used for long-distance voice calls for all North American sites, with SIP trunks [1]. VOICE OVER INTERNET PROTOCOL VoIP (Voice over Internet Protocol) is a method of voice transfer per internet protocol used in packet oriented networks shown in Figure 1. First, the A/D converter (Analog to Digital Converter) to convert analog voice to digital signals [2]; now, the bits have to be compressed in a good format for transmission. Then we have to insert our voice packets in data packets using a real-time protocol (RTP over UDP over IP), for signaling between customers terminal unit we need a signaling protocol SIP (Session Initiate Protocol). At receiver side, we have to disassemble packets, extract data, then convert them to analog voice signals and send them to sound card (or phone) [3]. Calling within the Network A platform is needed for a mobile device to communicate with a router. An android
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ISSN 2249-8613 (Online) ISSN 2321-5151 (Print)
Journal of
Communication Engineering & Systems JoCES September–December 2016 STM JOURNALS Scientific
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Medical
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