The urban traffic information manageanent has become an important way of solving traffic jam of cities. With the wider use of the third generation of mobile conmmunication （3G） networks, information management based...The urban traffic information manageanent has become an important way of solving traffic jam of cities. With the wider use of the third generation of mobile conmmunication （3G） networks, information management based on 3G will be a central issue of application. The paper designs a fi-amework of Global Posititoning System （GPS） vehicle navigating and guiding system using 3G mobile network and Glbal Information System （GIS） electronic map according to moving objects. It discusses moving object＇s time-space attrihltes which will be described by a five-field and a directed graph. It analyzes the GPS mobile apparatus＇ s software functions and hardware structures. Anti it improves the function of GPS mobile apparatus which provide the guiding function utilizing the shared information of traffic. The navigation based on the shortest path algortithm is been advanced to one based on the real-time traffic flow of moving objects, which help people travelling on roads more convenietly.展开更多
Currently cellular networks do not have sufficient capacity to accommodate the exponential growth of mobile data requirements.Data can be delivered between mobile terminals through peer-to-peer WiFi communications(e.g...Currently cellular networks do not have sufficient capacity to accommodate the exponential growth of mobile data requirements.Data can be delivered between mobile terminals through peer-to-peer WiFi communications(e.g.WiFi direct),but contacts between mobile terminals are frequently disrupted because of the user mobility.In this paper,we propose a Subscribe-and-Send architecture and an opportunistic forwarding protocol for it called HPRO.Under Subscribe-and-Send,a user subscribes contents on the Content Service Provider(CSP) but does not download the subscribed contents.Some users who have these contents deliver them to the subscribers through WiFi opportunistic peer-to-peer communications.Numerical simulations provide a robust evaluation of the forwarding performance and the traffic offloading performance of Subscribe-and-Send and HPRO.展开更多
In cellular network, several Time Difference Of Arrival (TDOA) location algorithms can be applied to mobile position estimation. However, each algorithm has its own limitations and none of them is proved to be the mos...In cellular network, several Time Difference Of Arrival (TDOA) location algorithms can be applied to mobile position estimation. However, each algorithm has its own limitations and none of them is proved to be the most reliable one in different channel environments. In this paper Kleine-Ostmann's data fusion model is modified and a collaborative location model which incorporates position estimate of two TDOA location algorithms is proposed.Analysis and simulation show that more reliable and accurate mobile position estimation can be achieved based on this model.展开更多
文摘The urban traffic information manageanent has become an important way of solving traffic jam of cities. With the wider use of the third generation of mobile conmmunication （3G） networks, information management based on 3G will be a central issue of application. The paper designs a fi-amework of Global Posititoning System （GPS） vehicle navigating and guiding system using 3G mobile network and Glbal Information System （GIS） electronic map according to moving objects. It discusses moving object＇s time-space attrihltes which will be described by a five-field and a directed graph. It analyzes the GPS mobile apparatus＇ s software functions and hardware structures. Anti it improves the function of GPS mobile apparatus which provide the guiding function utilizing the shared information of traffic. The navigation based on the shortest path algortithm is been advanced to one based on the real-time traffic flow of moving objects, which help people travelling on roads more convenietly.
基金supported by the National Natural Science Foundation of China under Grants No. 61100208,No. 61100205the Natural Science Foundation of Jiangsu Province under Grant No. BK2011169+1 种基金the Foundation of Beijing University of Posts and Telecommunications under Grant No. 2013RC0309supported by the EU FP7 Project REC-OGNITION:Relevance and Cognition for SelfAwareness in a Content-Centric Internet
文摘Currently cellular networks do not have sufficient capacity to accommodate the exponential growth of mobile data requirements.Data can be delivered between mobile terminals through peer-to-peer WiFi communications(e.g.WiFi direct),but contacts between mobile terminals are frequently disrupted because of the user mobility.In this paper,we propose a Subscribe-and-Send architecture and an opportunistic forwarding protocol for it called HPRO.Under Subscribe-and-Send,a user subscribes contents on the Content Service Provider(CSP) but does not download the subscribed contents.Some users who have these contents deliver them to the subscribers through WiFi opportunistic peer-to-peer communications.Numerical simulations provide a robust evaluation of the forwarding performance and the traffic offloading performance of Subscribe-and-Send and HPRO.
基金Supported by the National Natural Science Foundation of China(NNSF/RGC)(No.60218001)the National Key Lab, IETTC
文摘In cellular network, several Time Difference Of Arrival (TDOA) location algorithms can be applied to mobile position estimation. However, each algorithm has its own limitations and none of them is proved to be the most reliable one in different channel environments. In this paper Kleine-Ostmann's data fusion model is modified and a collaborative location model which incorporates position estimate of two TDOA location algorithms is proposed.Analysis and simulation show that more reliable and accurate mobile position estimation can be achieved based on this model.
