With the arrival of the 4G and 5G,the telecommunications networks have experienced a large expansion of these networks.That enabled the integration of many services and adequate flow,thus enabling the operators to res...With the arrival of the 4G and 5G,the telecommunications networks have experienced a large expansion of these networks.That enabled the integration of many services and adequate flow,thus enabling the operators to respond to the growing demand of users.This rapid evolution has given the operators to adapt,their methods to the new technologies that increase.This complexity becomes more important,when these networks include several technologies to access different from the heterogeneous network like in the 4G network.The dimensional new challenges tell the application and the considerable increase in demand for services and the compatibility with existing networks,the management of mobility intercellular of users and it offers a better quality of services.Thus,the proposed solution to meet these new requirements is the sizing of the EPC(Evolved Packet Core)core network to support the 5G access network.For the case of Orange Guinea,this involves setting up an architecture for interconnecting the core networks of Sonfonia and Camayenne.The objectives of our work are of two orders:(1)to propose these solutions and recommendations for the heart network EPC sizing and the deployment to be adopted;(2)supply and architectural interconnection in the heart network EPC and an existing heart network.In our work,the model of traffic in communication that we use to calculate the traffic generated with each technology has link in the network of the heart.展开更多
In relay-assisted cooperative communication,relay nodes help forwarding the information of a source node in case of link failure between the source and a destination.Although user cooperation improves the overall effi...In relay-assisted cooperative communication,relay nodes help forwarding the information of a source node in case of link failure between the source and a destination.Although user cooperation improves the overall efficiency of the network,it requires incentive to stimulate potential relay nodes to assist the source by forwarding its data to the destination.Moreover,the potential relays are better informed than the source about their channel conditions to destination,which results in asymmetric information between the source and the relays.In this paper,we study the problem of lack of forwarding incentive in cooperative communication when channel state information of relays is private information and not known by the source.To tackle this problem,we apply the principle of contract theory to a cooperative wireless system.Source first designs incentive compatible and individually rational contract,consisting of a set of power-credit pairs.Then it broadcasts contract items to nearby nodes.Once the source node receives reply messages from the volunteer relays,it chooses one or more relays based on its requirements and communication starts.Simulation results show how credit assignment works in order to stimulate relays to cooperate and prevents relays from cheating behavior.展开更多
Fleet Management System (FMS) is a highly applicable system which gets more and more attention among industrial field. Recent years, fuel consumption has become one of the most concerned topics, hence, establishment o...Fleet Management System (FMS) is a highly applicable system which gets more and more attention among industrial field. Recent years, fuel consumption has become one of the most concerned topics, hence, establishment of a fuel consumption monitoring system is required. In this study, based-on the FMS, a system which was capable of precisely monitoring and calculating the fuel consumption was designed. This FMS was composed of the front end Vehicle Tracking System (VTS) and the back end Management Server (MS). VTS was established and installed into the vehicles, based on several well-known technologies, such as Mobile Telecommunications Technology of GPRS or 3G, Global Positioning System (GPS), and On-Board Diagnostics II (OBD-II). In addition, VTS was also connected with the Vehicle Electronic Control Unit (VECU) through the OBD-II interface. By using GPRS/3G technology and the TCP/IP communication protocol, real-time vehicle operation data obtained from the OBD-II and positioning information from the GPS could be sent backward to the MS. The MS was designed through JBoss Developer Studio, and included the Data Collector (DC) and Web server. The DC gathers data sent back from VTS and the Web server calculates and decides the vehicle's present situation according to the data. The result can also be presented on websites by the Web server. In this study, the fuel consumption status of vehicles could be performed. Furthermore, the Web service also provided the users instant online manipulation.展开更多
A model is proposed along with empirical investigation to prove the existence of network effects in China’s mobile telecommunications market. Futhernore, network effects on China’s mobile telecommunications are esti...A model is proposed along with empirical investigation to prove the existence of network effects in China’s mobile telecommunications market. Futhernore, network effects on China’s mobile telecommunications are estimated with a dynamic model. The structural parameters are identified from regression coefficients and the results are analyzed and compared with another literature. Data and estimation issues are also discussed. Conclusions are drawn that network effects are significant in China’s mobile telecommunications market, and that ignoring network effects leads to bad policy making.展开更多
Handover in Digital Video Broadcasting for Handhelds(DVB-H) aims to provide continuous mobile broadcasting services when a user is traveling through cell boundaries.A good handover control can improve the power effici...Handover in Digital Video Broadcasting for Handhelds(DVB-H) aims to provide continuous mobile broadcasting services when a user is traveling through cell boundaries.A good handover control can improve the power efficiency and gain much better reception quality.This letter provides a novel approach for DVB-H handover based on DVB-H/Universal Mobile Telecommunications System(UMTS) hybrid network,which moves the main handover function from the terminals to the networks,so that it reduces the operation complexity of the terminals and increases the power saving.When the terminal can not receive the DVB-H signal in the transmission shadow areas or because of some other reasons,the UMTS networks may offer the same service to users to make the service continuous.As the UMTS networks have the topology of the DVB-H networks,by communicating with the terminals,the UMTS networks can help the terminals to predict the handover,and avoid unnecessary handover.展开更多
"Without an appropriate research setting, a study cannot be qualified as a reasonable piece", this notion is manifested in the methodological polices. In this research, we attempt to examine previous studies within ..."Without an appropriate research setting, a study cannot be qualified as a reasonable piece", this notion is manifested in the methodological polices. In this research, we attempt to examine previous studies within the scope of technology evolution and market perception in telecommunication industry through extracting research structures, methodologies, corresponding variables, and processing methods. A general process of social scientific research is adopted to analyze eighty-four selected papers; and simultaneously, the framework for doing this analysis is established, as well. In this manner, we inspect the subjects and the issues in these papers according to product types, academic domains, and divisions of technological evolution (from 1G to 4G). Then, their research designs are anatomized into the key dimensions of general research conventions. This research eventually provides an entire picture of a research scenario for mobile telecommunication industry; and apparently, this framewbrk can help scholars to establish specific tendencies for academic scenarios in future research plans. Also, we propose the main streams and emerging issues can be expected to engage in the future within both theacademic and the operational fields.展开更多
文摘With the arrival of the 4G and 5G,the telecommunications networks have experienced a large expansion of these networks.That enabled the integration of many services and adequate flow,thus enabling the operators to respond to the growing demand of users.This rapid evolution has given the operators to adapt,their methods to the new technologies that increase.This complexity becomes more important,when these networks include several technologies to access different from the heterogeneous network like in the 4G network.The dimensional new challenges tell the application and the considerable increase in demand for services and the compatibility with existing networks,the management of mobility intercellular of users and it offers a better quality of services.Thus,the proposed solution to meet these new requirements is the sizing of the EPC(Evolved Packet Core)core network to support the 5G access network.For the case of Orange Guinea,this involves setting up an architecture for interconnecting the core networks of Sonfonia and Camayenne.The objectives of our work are of two orders:(1)to propose these solutions and recommendations for the heart network EPC sizing and the deployment to be adopted;(2)supply and architectural interconnection in the heart network EPC and an existing heart network.In our work,the model of traffic in communication that we use to calculate the traffic generated with each technology has link in the network of the heart.
文摘In relay-assisted cooperative communication,relay nodes help forwarding the information of a source node in case of link failure between the source and a destination.Although user cooperation improves the overall efficiency of the network,it requires incentive to stimulate potential relay nodes to assist the source by forwarding its data to the destination.Moreover,the potential relays are better informed than the source about their channel conditions to destination,which results in asymmetric information between the source and the relays.In this paper,we study the problem of lack of forwarding incentive in cooperative communication when channel state information of relays is private information and not known by the source.To tackle this problem,we apply the principle of contract theory to a cooperative wireless system.Source first designs incentive compatible and individually rational contract,consisting of a set of power-credit pairs.Then it broadcasts contract items to nearby nodes.Once the source node receives reply messages from the volunteer relays,it chooses one or more relays based on its requirements and communication starts.Simulation results show how credit assignment works in order to stimulate relays to cooperate and prevents relays from cheating behavior.
文摘Fleet Management System (FMS) is a highly applicable system which gets more and more attention among industrial field. Recent years, fuel consumption has become one of the most concerned topics, hence, establishment of a fuel consumption monitoring system is required. In this study, based-on the FMS, a system which was capable of precisely monitoring and calculating the fuel consumption was designed. This FMS was composed of the front end Vehicle Tracking System (VTS) and the back end Management Server (MS). VTS was established and installed into the vehicles, based on several well-known technologies, such as Mobile Telecommunications Technology of GPRS or 3G, Global Positioning System (GPS), and On-Board Diagnostics II (OBD-II). In addition, VTS was also connected with the Vehicle Electronic Control Unit (VECU) through the OBD-II interface. By using GPRS/3G technology and the TCP/IP communication protocol, real-time vehicle operation data obtained from the OBD-II and positioning information from the GPS could be sent backward to the MS. The MS was designed through JBoss Developer Studio, and included the Data Collector (DC) and Web server. The DC gathers data sent back from VTS and the Web server calculates and decides the vehicle's present situation according to the data. The result can also be presented on websites by the Web server. In this study, the fuel consumption status of vehicles could be performed. Furthermore, the Web service also provided the users instant online manipulation.
文摘A model is proposed along with empirical investigation to prove the existence of network effects in China’s mobile telecommunications market. Futhernore, network effects on China’s mobile telecommunications are estimated with a dynamic model. The structural parameters are identified from regression coefficients and the results are analyzed and compared with another literature. Data and estimation issues are also discussed. Conclusions are drawn that network effects are significant in China’s mobile telecommunications market, and that ignoring network effects leads to bad policy making.
基金the National Science Fund for Distinguished Young Scholars (No.60525110)the National 973 Program (No.2007CB307100, No.2007CB307103)+1 种基金the Program for New Century Excellent Talents in University (No. NCET-04-0111)the Development Fund Project for Electronic and Information Industry (Mobile Service and Application System Based on 3G)
文摘Handover in Digital Video Broadcasting for Handhelds(DVB-H) aims to provide continuous mobile broadcasting services when a user is traveling through cell boundaries.A good handover control can improve the power efficiency and gain much better reception quality.This letter provides a novel approach for DVB-H handover based on DVB-H/Universal Mobile Telecommunications System(UMTS) hybrid network,which moves the main handover function from the terminals to the networks,so that it reduces the operation complexity of the terminals and increases the power saving.When the terminal can not receive the DVB-H signal in the transmission shadow areas or because of some other reasons,the UMTS networks may offer the same service to users to make the service continuous.As the UMTS networks have the topology of the DVB-H networks,by communicating with the terminals,the UMTS networks can help the terminals to predict the handover,and avoid unnecessary handover.
文摘"Without an appropriate research setting, a study cannot be qualified as a reasonable piece", this notion is manifested in the methodological polices. In this research, we attempt to examine previous studies within the scope of technology evolution and market perception in telecommunication industry through extracting research structures, methodologies, corresponding variables, and processing methods. A general process of social scientific research is adopted to analyze eighty-four selected papers; and simultaneously, the framework for doing this analysis is established, as well. In this manner, we inspect the subjects and the issues in these papers according to product types, academic domains, and divisions of technological evolution (from 1G to 4G). Then, their research designs are anatomized into the key dimensions of general research conventions. This research eventually provides an entire picture of a research scenario for mobile telecommunication industry; and apparently, this framewbrk can help scholars to establish specific tendencies for academic scenarios in future research plans. Also, we propose the main streams and emerging issues can be expected to engage in the future within both theacademic and the operational fields.