Autonomous wireless networks

Abstract

A device is operable to use received signals to divide time into a succession of frames, each frame having plural consecutive timeslots, and into a succession of four or more superframes. A transmitter is operated only in a single timeslot in one frame. A receiver is operated in the other timeslots in the frame and for all timeslots of immediately preceding and following frames, and in no other frames. This allows devices to predict periods in which to hibernate or carry out intensive tasks. The device determines which timeslots of the first frame are occupied to provide local awareness information, and transmits it as a code on its transmit timeslot along with payload data. This allows other devices in a network to obtain information about their local environment and about the environment of their neighbours. Routing decisions are made on this basis.

Description

[0001] This patent application is related to a patent application filed on the same date by the same applicant and having internal reference number A31068, and claims priority from European patent application number 06251889.9. technical field [0002] The present invention relates to autonomous networks of wireless devices and has been developed for use in sensor networks for monitoring environmental conditions in situations where provision of a fixed infrastructure is impractical, such as oceanography. However, the invention is also applicable to other areas where wireless devices are relatively free to move relative to each other and use little or no fixed infrastructure. Example applications include battlefield use, disaster recovery, and inter-vehicle communication (intelligent vehicle highway management system). Background technique [0003] Wireless devices have many conflicting requirements, especially between extended battery life and the speed and reliability of da...

AI Technical Summary

Problems solved by technology

Generally, communication reliability and data relay speed can be improved by increasing transmitter power and the frequency of data transfers, but these measures increase power consumption and thus reduce battery life

[0004] Furthermore, it is also a challenge how to provide wireless devices that are freely movable, for example on ocean currents, since the devices can thus move relative to each other, so that the network topology changes over time

Since the reliability and actual existence of a communication path is sensitive to the correct operation of each device in the path and the reliability of the links between each device and the devices directly upstream and directly downstream of that device in the path, when the This is especially problematic when devices act as relays to relay data from devices that are too far away from the base station to have direct access to the base station

Images