摘要:
Provided are a system and method for position awareness that can be used indoors in a large-scale environment and can minimize generation of radio frequency (RF) and ultrasonic waves in a wireless sensor network including low-priced sensor nodes capable of precise position measurement, thus improving energy efficiency by reducing unnecessary power consumption. The method includes the steps of: (a) calculating initial position coordinates using beacon information received from adjacent beacons through a broadcast beacon solicitation signal, sending a synchronization signal to the beacons, and synchronizing the beacons; (b) receiving ultrasonic waves generated from the adjacent beacons activated by a broadcast start message, and calculating position coordinates; and (c) when the calculated position coordinates correspond to a predetermined hand-off threshold position, transmitting a hand-off process message to a newly activated beacon, and executing a hand-off process routine.
摘要:
A method of providing a routing protocol in a sensor network includes the steps of: initializing a routing table and searching a network device of a node to initialize a host; opening a socket when there is a request for forwarding of an IP (Internet Protocol) packet from an upper layer or when there is a request through the network device; determining whether there is the IP packet forwarding request of the upper layer node or whether the packet is received from the network device; if there is the IP packet forwarding request of the upper layer, searching the routing table, and determining whether or not there is a destination node which intends to transmit the packet, and returning to a main loop if there is the destination node; and if the packet is received through the network device, determining types of the received packets and performing RREQ (route request) process, IDLE process, RREP (route reply) process, RERR (route error) process, and RREP_ACK (route reply acknowledgement) process.