Scaleable, wireless Web enabled sensor networks

Our goal was to develop a long life, low cost, scalable wireless sensing network, which collects and distributes data from a wide variety of sensors over the Internet Time division multiple access was employed with low-power RF transmitter nodes to communicate digital data to a receiver (range 1/3 mile). Data from this remote receiver is relayed via 802.11b to a central information gateway (range 1-2 miles). Multiple receivers can be linked to this gateway, resulting in an easily-addressed, hierarchical spoke-and-hub network topology. This system presents an attractive, inexpensive solution for deploying thousands of sensors with a coverage area up to 10 square miles.