Abstract: A system and process for determining the location of persons and objects using transmitters (TXs) that transmit location messages to at least one receiver connected to a computer, in a network of computers. The TXs are small, battery-powered, radio frequency transmitters carried by the person or object whose location is being tracked. The location message signals are picked up by one or more receivers (RXs) scattered throughout an environment. Each TX transmits a code with a unique identifier, and each RX also has a unique identifier. The RXs measure the signal strength of each location message transmission. Each RX is connected to a computer, which is in turn connected to a network. The RX computers send the data messages including the TX identifier, radio signal strength, and RX identifier to a central computer via the network. The central computer uses this information to determine the location of the TXs.

Abstract: A system and process for determining the location of persons and objects using transmitters (TXs) that transmit location messages to at least one receiver connected to a computer, in a network of computers. The TXs are small, battery-powered, radio frequency transmitters carried by the person or object whose location is being tracked. The location message signals are picked up by one or more receivers (RXs) scattered throughout an environment. Each TX transmits a code with a unique identifier, and each RX also has a unique identifier. The RXs measure the signal strength of each location message transmission. Each RX is connected to a computer, which is in turn connected to a network. The RX computers send the data messages including the TX identifier, radio signal strength, and RX identifier to a central computer via the network. The central computer uses this information to determine the location of the TXs.

Abstract: A system for locating any mobile body of a plurality thereof within a predetermined environment, wherein each mobile body carries a transmitter (10 to 18), each transmitter producing a unique identifying signal, and a plurality of receivers (20 to 32) located in a corresponding plurality of defined regions in the environment, each receiver incorporating a FIFO buffer memory (28) into which carrier identifying data is inserted and a controller for interrogating the receiver means in turn to link the identification data with location data. (FIG. 1 ). A carrier authentication system is also described.

Abstract: A system for locating any mobile body or a plurality thereof within a predetermined environment, wherein each mobile body carries a transmitter (10 to 18), each transmitter producing a unique identifying signal, and a plurality of receivers (20 to 32) located in a corresponding plurality of defined regions in the environment, each receiver incorporating a FIFO buffer memory (28) into which carrier identifying data is inserted and a controller for interrogating the receiver means in turn to link the identification data with location data.

Abstract: A mesh connected local area network provides automatic packet switching and routing between host computers coupled to the network. The network has a multiplicity of cut-through, nonblocking switches, each capable of simultaneously routing a multiplicity of data packets. Low host-to-host latency is achieved through the use of cut-through switches with separate internal buffers for each packet being routed. The switches are interconnected with one another and are coupled to the host computers of the network by point to point full duplex links. While each switch can be coupled to ten or more network members, i.e., switches and hosts, each link is coupled to only two network members and is dedicated to carrying signals therebetween. Whenever a new switch or link is added to the network, and whenever a switch or link fails, the switches in the network automatically reconfigure the network by recomputing the set of legal paths through the network.