Pub Date : 2018-01-01DOI: 10.4172/2090-4886.1000156
Ebenezer Malcalm, Bernice Abena Darkoah Agyemang
Digital Television Transmission is the streaming of impairment free digitally processed and multiplexed signals in a binary on/off bit sequences to all receiving locations within coverage area [1]. Television signal whether digital or analogue can be delivered through three main platforms; cable, satellite and terrestrial wireless. Digital Cable Television Transmission is the transmission of television signals to receivers through direct cable connection from an underground cable network with improved interactivity and has a higher multiplex capacity compared to terrestrial digital television [2]. Digital Satellite Television (TV) transmission is the transmission of digital television signal from a base station towards a satellite which is then processed and converted into frequency range that can be viewed using parabolic antenna [3] and has the benefit of reduced transponder cost and increased channel capacity for given transponder space [2]. Digital Terrestrial television transmission is seen as the most important means of delivery of digital television signals, provides real and nonreal-time delivery of content, point-to-multipoint and one to many architecture, delivering geographically local content and supports receivers that can move, free to air and subscription services [4]. The terrestrial digital compression technology allows many channels to be broadcasted with the same amount of spectrum used by one analogue channel and receiving of digital signals on conversional television aerial by conversion into analogue by a set-top box (STB) or viewed with integrated digital television set (IDTV) [2]. Digital Terrestrial Television is the transmission of digital television signals from a ground based transmitter operating in the UHF or VHF band which is radiated as radio waves and are received using a UHF or VHF antenna [1]. Digital television transmission is the new wave of broadcasting and the future of television broadcasting [4]. It has naturally evolved from Analogue Television Transmission and involves the process of generating television contents, editing, finalizing, storing, transmitting and receiving just like in the analogue system. In digital television transmission, all the processes are digital based; image, sound and information are generated and received as digital signals unlike Analogue Television Transmission where content generation and transmission are through analogue signals [5].
{"title":"Examination of State of Art Technology in Digital Television Transmission in Ghana: Case Study of Knet Limited","authors":"Ebenezer Malcalm, Bernice Abena Darkoah Agyemang","doi":"10.4172/2090-4886.1000156","DOIUrl":"https://doi.org/10.4172/2090-4886.1000156","url":null,"abstract":"Digital Television Transmission is the streaming of impairment free digitally processed and multiplexed signals in a binary on/off bit sequences to all receiving locations within coverage area [1]. Television signal whether digital or analogue can be delivered through three main platforms; cable, satellite and terrestrial wireless. Digital Cable Television Transmission is the transmission of television signals to receivers through direct cable connection from an underground cable network with improved interactivity and has a higher multiplex capacity compared to terrestrial digital television [2]. Digital Satellite Television (TV) transmission is the transmission of digital television signal from a base station towards a satellite which is then processed and converted into frequency range that can be viewed using parabolic antenna [3] and has the benefit of reduced transponder cost and increased channel capacity for given transponder space [2]. Digital Terrestrial television transmission is seen as the most important means of delivery of digital television signals, provides real and nonreal-time delivery of content, point-to-multipoint and one to many architecture, delivering geographically local content and supports receivers that can move, free to air and subscription services [4]. The terrestrial digital compression technology allows many channels to be broadcasted with the same amount of spectrum used by one analogue channel and receiving of digital signals on conversional television aerial by conversion into analogue by a set-top box (STB) or viewed with integrated digital television set (IDTV) [2]. Digital Terrestrial Television is the transmission of digital television signals from a ground based transmitter operating in the UHF or VHF band which is radiated as radio waves and are received using a UHF or VHF antenna [1]. Digital television transmission is the new wave of broadcasting and the future of television broadcasting [4]. It has naturally evolved from Analogue Television Transmission and involves the process of generating television contents, editing, finalizing, storing, transmitting and receiving just like in the analogue system. In digital television transmission, all the processes are digital based; image, sound and information are generated and received as digital signals unlike Analogue Television Transmission where content generation and transmission are through analogue signals [5].","PeriodicalId":91517,"journal":{"name":"International journal of sensor networks and data communications","volume":"07 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2018-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.4172/2090-4886.1000156","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70965671","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2018-01-01DOI: 10.4172/2090-4886.1000E111
Y. Ma
There is significant meaning for the development of trace gas detection in the atmospheric environment monitoring, long distance detection of explosives and the physiological state of biont. For example, the trace gas of atmosphere, however, always exists with the concentration of pptv-ppmv. Although the concentration is very low, it has a great impact on the environment. Detecting this trace gases’ component, concentration and its variation in the interspaces and period precisely have an extraordinary meaning, especially in the basic research fields and applied technique domain.
{"title":"Trace Gas Sensing Based on Laser Photoacoustic Spectroscopy","authors":"Y. Ma","doi":"10.4172/2090-4886.1000E111","DOIUrl":"https://doi.org/10.4172/2090-4886.1000E111","url":null,"abstract":"There is significant meaning for the development of trace gas detection in the atmospheric environment monitoring, long distance detection of explosives and the physiological state of biont. For example, the trace gas of atmosphere, however, always exists with the concentration of pptv-ppmv. Although the concentration is very low, it has a great impact on the environment. Detecting this trace gases’ component, concentration and its variation in the interspaces and period precisely have an extraordinary meaning, especially in the basic research fields and applied technique domain.","PeriodicalId":91517,"journal":{"name":"International journal of sensor networks and data communications","volume":"05 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2018-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.4172/2090-4886.1000E111","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70966098","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2017-08-10DOI: 10.4172/2090-4886-C1-008
pMario Scholzelp
{"title":"New tools for developing dependable Wireless sensor networks","authors":"pMario Scholzelp","doi":"10.4172/2090-4886-C1-008","DOIUrl":"https://doi.org/10.4172/2090-4886-C1-008","url":null,"abstract":"","PeriodicalId":91517,"journal":{"name":"International journal of sensor networks and data communications","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2017-08-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70969833","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2017-08-10DOI: 10.4172/2090-4886-C1-009
P. Mehtap
{"title":"Next generation antennas for high throughput Wireless communication in weak electromagnetic environments","authors":"P. Mehtap","doi":"10.4172/2090-4886-C1-009","DOIUrl":"https://doi.org/10.4172/2090-4886-C1-009","url":null,"abstract":"","PeriodicalId":91517,"journal":{"name":"International journal of sensor networks and data communications","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2017-08-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70970025","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2017-08-10DOI: 10.4172/2090-4886-C1-007
pZuriati Ahmad Zukarnainp
{"title":"Quantum communication simulator as a simulation tool for quantum communication experiment","authors":"pZuriati Ahmad Zukarnainp","doi":"10.4172/2090-4886-C1-007","DOIUrl":"https://doi.org/10.4172/2090-4886-C1-007","url":null,"abstract":"","PeriodicalId":91517,"journal":{"name":"International journal of sensor networks and data communications","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2017-08-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70969661","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2017-07-11DOI: 10.4172/2090-4886.1000152
S. SaritaÅ, Erdal Turgut, M. Kundakçı, B. Gürbulak, M. Yıldırım
This work describes hematite (a-Fe2O3) and ZnxFe3-XO4 thin films prepared by Chemical Spray Pyrolysis (CSP) method. CSP method allows an optimal control of stoichiometry and impurity incorporation, hematite films modified with Zn2+ was also prepared. Moreover, the most attracting characteristics of the hematite are its stability in neutral and basic solutions, abundance and band gap energy (2.0–2.2 eV) which permits it to absorb approximately 40% of the incident solar spectrum on earth. Nevertheless, the performance of hematite electrodes for water oxidation is restricted by their poor charge transport properties. Hematite has low conductivity and low charge-carrier mobility. In addition, the photoexcited electron–hole pairs have short life time (~10-12 s), which makes the hole diffusion length to be also short (2–4 nm). The charge transport properties of hematite can be improved by dopping. We demonstrated to increase the conductivity of hematite by dopping it with metal cations with 2+ charges which improved the photocatalytic properties. Doping with metal cations with 2+ charges has also brought good photoelectrochemical results. So we iron oxide and Zn-doped iron oxide compounds have been investigated. The structural, optical and magnetic properties of a-Fe2O3 and ZnxFe3-xO4 compounds have been extensively investigated. XRD, XPS, Raman, FE-SEM and AFM techniques have been used for structural analysis; Absorption technique has been used for optical properties; Hall and Vibrating Sample Magnetometer (VSM) techniques have been used for magnetic properties.
{"title":"Compared with a-Fe2O3 and ZnxFe3-XO4 Thin Films Grown by Chemical Spray Pyrolysis","authors":"S. SaritaÅ, Erdal Turgut, M. Kundakçı, B. Gürbulak, M. Yıldırım","doi":"10.4172/2090-4886.1000152","DOIUrl":"https://doi.org/10.4172/2090-4886.1000152","url":null,"abstract":"This work describes hematite (a-Fe2O3) and ZnxFe3-XO4 thin films prepared by Chemical Spray Pyrolysis (CSP) method. CSP method allows an optimal control of stoichiometry and impurity incorporation, hematite films modified with Zn2+ was also prepared. Moreover, the most attracting characteristics of the hematite are its stability in neutral and basic solutions, abundance and band gap energy (2.0–2.2 eV) which permits it to absorb approximately 40% of the incident solar spectrum on earth. Nevertheless, the performance of hematite electrodes for water oxidation is restricted by their poor charge transport properties. Hematite has low conductivity and low charge-carrier mobility. In addition, the photoexcited electron–hole pairs have short life time (~10-12 s), which makes the hole diffusion length to be also short (2–4 nm). The charge transport properties of hematite can be improved by dopping. We demonstrated to increase the conductivity of hematite by dopping it with metal cations with 2+ charges which improved the photocatalytic properties. Doping with metal cations with 2+ charges has also brought good photoelectrochemical results. So we iron oxide and Zn-doped iron oxide compounds have been investigated. The structural, optical and magnetic properties of a-Fe2O3 and ZnxFe3-xO4 compounds have been extensively investigated. XRD, XPS, Raman, FE-SEM and AFM techniques have been used for structural analysis; Absorption technique has been used for optical properties; Hall and Vibrating Sample Magnetometer (VSM) techniques have been used for magnetic properties.","PeriodicalId":91517,"journal":{"name":"International journal of sensor networks and data communications","volume":"2017 1","pages":"1-7"},"PeriodicalIF":0.0,"publicationDate":"2017-07-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.4172/2090-4886.1000152","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47102557","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2017-06-28DOI: 10.4172/2090-4886.1000151
Nayak Ja, R. ch, Prasad Vvkdv
Energy efficient routing is a one of the major trusted area in Wireless Sensor Networks (WSNs). The wireless sensor network composed of a large number of sensor nodes which has limited energy resource. The sensor nodes are working through the battery, energy saving becomes more vital issue in WSNs. The routing algorithms assure the concept of energy saving without affecting the Quality of Service (QoS) Parameters like Throughput, End to End Delay, Overhead and Packet Delivery Ratio. In the existing system the Enhanced Energy Efficient Multipath Routing (EEEMR) Protocol is implemented. The EEEMR Protocol is modification of AOMDV Protocol. In this paper, we are implementing Clustering algorithm in EEEMR Protocol. The development of cluster based sensor networks have recently shown to decrease the system delay, overhead and increase the system throughput and packet delivery ratio. Simulation is performed using NS2 and results shows that the proposed system is better than the existing system. The proposed system energy consumption is decreased by 13% compared to the existing system.
{"title":"Improving the Network Life Time of Wireless Sensor Network using EEEMR Protocol with Clustering Algorithm","authors":"Nayak Ja, R. ch, Prasad Vvkdv","doi":"10.4172/2090-4886.1000151","DOIUrl":"https://doi.org/10.4172/2090-4886.1000151","url":null,"abstract":"Energy efficient routing is a one of the major trusted area in Wireless Sensor Networks (WSNs). The wireless sensor network composed of a large number of sensor nodes which has limited energy resource. The sensor nodes are working through the battery, energy saving becomes more vital issue in WSNs. The routing algorithms assure the concept of energy saving without affecting the Quality of Service (QoS) Parameters like Throughput, End to End Delay, Overhead and Packet Delivery Ratio. In the existing system the Enhanced Energy Efficient Multipath Routing (EEEMR) Protocol is implemented. The EEEMR Protocol is modification of AOMDV Protocol. In this paper, we are implementing Clustering algorithm in EEEMR Protocol. The development of cluster based sensor networks have recently shown to decrease the system delay, overhead and increase the system throughput and packet delivery ratio. Simulation is performed using NS2 and results shows that the proposed system is better than the existing system. The proposed system energy consumption is decreased by 13% compared to the existing system.","PeriodicalId":91517,"journal":{"name":"International journal of sensor networks and data communications","volume":"2017 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2017-06-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.4172/2090-4886.1000151","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49606142","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2017-05-18DOI: 10.4172/2090-4886.1000150
Darwish Im, E. Sm
An integration of sensing environment with the numerous deployments of sensor nodes in Wireless Sensor Network (WSN) causes the severe security threats and hence the trust assurance mechanisms are required. For the large scale WSN, the existence of a number of intermediate nodes is responsible for the data forwarding to the sink node. Due to the battery operated sensors, the recharge and replace mechanisms suffer from the energy conservation and minimum network lifetime. The identification of fault nodes on the transmission path plays the major role in energy conservation. With the dense deployment of sensor nodes, the failures in node and link are high that disrupts the entire communication. This paper proposes the suitable alternative fault-free path prediction model to perform the communication among the nodes. Initially, the sensor nodes are deployed in the WSN environment. Once the initialization of source and destination nodes are over, the path between them is predicted through the Hamiltonian path prediction model. During the failure, scenario, this paper estimates the node and link parameters such as Received Signal Strength Indicator (RSSI), queue size, response time, and bandwidth are individually estimated and group them into the Quality Factor (QF). Based on the QF, the proposed work predicts the fault-free link to alleviate the unnecessary transmissions to the fault node and reduces the energy consumption. The comparison between the proposed Hamiltonian Path-based Hyper Cube (HPHC) network with the existing fault detection mechanisms regarding the performance measures such as Packet Delivery Ratio (PDR), fault node detection rate, throughput and end-to-end delay assures the effectiveness of HPHC in WSN communication.
{"title":"Enhanced Algorithms for Fault Nodes Recovery in Wireless Sensors Network","authors":"Darwish Im, E. Sm","doi":"10.4172/2090-4886.1000150","DOIUrl":"https://doi.org/10.4172/2090-4886.1000150","url":null,"abstract":"An integration of sensing environment with the numerous deployments of sensor nodes in Wireless Sensor Network (WSN) causes the severe security threats and hence the trust assurance mechanisms are required. For the large scale WSN, the existence of a number of intermediate nodes is responsible for the data forwarding to the sink node. Due to the battery operated sensors, the recharge and replace mechanisms suffer from the energy conservation and minimum network lifetime. The identification of fault nodes on the transmission path plays the major role in energy conservation. With the dense deployment of sensor nodes, the failures in node and link are high that disrupts the entire communication. This paper proposes the suitable alternative fault-free path prediction model to perform the communication among the nodes. Initially, the sensor nodes are deployed in the WSN environment. Once the initialization of source and destination nodes are over, the path between them is predicted through the Hamiltonian path prediction model. During the failure, scenario, this paper estimates the node and link parameters such as Received Signal Strength Indicator (RSSI), queue size, response time, and bandwidth are individually estimated and group them into the Quality Factor (QF). Based on the QF, the proposed work predicts the fault-free link to alleviate the unnecessary transmissions to the fault node and reduces the energy consumption. The comparison between the proposed Hamiltonian Path-based Hyper Cube (HPHC) network with the existing fault detection mechanisms regarding the performance measures such as Packet Delivery Ratio (PDR), fault node detection rate, throughput and end-to-end delay assures the effectiveness of HPHC in WSN communication.","PeriodicalId":91517,"journal":{"name":"International journal of sensor networks and data communications","volume":"6 1","pages":"1-9"},"PeriodicalIF":0.0,"publicationDate":"2017-05-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.4172/2090-4886.1000150","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43311634","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2016-11-15DOI: 10.4172/2090-4886.1000148
Ramkrishna Ghosh
Wireless Sensor Networks (WSNs) and Wireless Multimedia Sensor Networks (WMSNs) consist of wirelessly interconnected sensor nodes which can collect, deliver and process information in different application areas. Power Consumption in these networks is a major problem. Some of the applications include landslide detection, glacial monitoring, wildlife tracking, health care, military applications, environmental monitoring and a large number of applications to robotics, “internet of things” projects. This paper will illustrate the fundamental characteristics of WSN followed by different power consumption protocols. Here we have performed the comparative performance analysis of different power consumption protocols.
{"title":"Comparative Performance Analysis of Routing Protocols in Wireless Sensor Network","authors":"Ramkrishna Ghosh","doi":"10.4172/2090-4886.1000148","DOIUrl":"https://doi.org/10.4172/2090-4886.1000148","url":null,"abstract":"Wireless Sensor Networks (WSNs) and Wireless Multimedia Sensor Networks (WMSNs) consist of wirelessly interconnected sensor nodes which can collect, deliver and process information in different application areas. Power Consumption in these networks is a major problem. Some of the applications include landslide detection, glacial monitoring, wildlife tracking, health care, military applications, environmental monitoring and a large number of applications to robotics, “internet of things” projects. This paper will illustrate the fundamental characteristics of WSN followed by different power consumption protocols. Here we have performed the comparative performance analysis of different power consumption protocols.","PeriodicalId":91517,"journal":{"name":"International journal of sensor networks and data communications","volume":"5 1","pages":"1-5"},"PeriodicalIF":0.0,"publicationDate":"2016-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.4172/2090-4886.1000148","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70965888","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2016-09-25DOI: 10.4172/2090-4886.1000E110
M. Ghomaishi
Characteristics of fiber optics under the various dosimeter aspects instant different radiation and wide ranges of doses have been reported in many case-studies. However, generally, optical fibers which is available commercially in the market have been used, which provided lots of ambiguous on the subject of dosimeter characteristics regarding to various fabrication process, materials doped and element concentrations used by different manufacturers [1,2].
{"title":"Optical Fibre Dosimetry","authors":"M. Ghomaishi","doi":"10.4172/2090-4886.1000E110","DOIUrl":"https://doi.org/10.4172/2090-4886.1000E110","url":null,"abstract":"Characteristics of fiber optics under the various dosimeter aspects instant different radiation and wide ranges of doses have been reported in many case-studies. However, generally, optical fibers which is available commercially in the market have been used, which provided lots of ambiguous on the subject of dosimeter characteristics regarding to various fabrication process, materials doped and element concentrations used by different manufacturers [1,2].","PeriodicalId":91517,"journal":{"name":"International journal of sensor networks and data communications","volume":"5 1","pages":"1-1"},"PeriodicalIF":0.0,"publicationDate":"2016-09-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70966349","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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