| 摘要 |
A data reduction, processing and dissemination system provides selected data collected from tracked assets to customers according to specified requirements. The location of a tracked asset is determined using a GPS receiver and a satellite transceiver in tracking units affixed to the assets being tracked. The tracking units are formed into a local area network of tracking units. Each tracking unit is identified by a unique identification (ID) and includes various sensors which monitor environmental conditions. Within the network, one tracking unit is selected to act as a master and the remaining tracking units function as slaves. The slave tracking units periodically transmit their respective IDs together with sensor data and battery condition to the master tracking unit. The master tracking unit, in turn, maintains a list of IDs of the slave tracking units in the network and collects the data transmitted to it by the slave tracking units. Periodically, the master tracking unit transmits to a central station a frame of data identifying all tracking units in its network together with environmental and battery data collected from the tracking units. All the data are collected and processed at the central station. The data are processed for specific customers and may take the form of textual reports, exception reporting, graphical display, etc. Data are disseminated via various telecommunications carriers, as specified by the customers. <IMAGE> |
