Collision-free Time Slot Reuse in Multi-hop Wireless Sensor Networks

• Published in: 2005 International Conference on Intelligent Sensors, Sensor Networks and Information Processing pp. 101 - 107
• Main Authors: van Hoesel, L., Havinga, P.
• Format: Conference Proceeding
• Language: English
• Published: IEEE 2005
• Subjects: Access protocols; Computer science; Electronic mail; Intelligent networks; Mathematics; Media Access Protocol; Scheduling; Spread spectrum communication; Wireless application protocol; Wireless sensor networks
• ISBN: 0780393996; 9780780393998
• DOI: 10.1109/ISSNIP.2005.1595563

To ensure a long-lived network of wireless communicating sensors, we are in need of a medium access control protocol that is able to prevent energy-wasting effects like idle listening, hidden terminal problem or collision of packets. Schedule-based medium access protocols are in general robust against these effects, but require a mechanism to establish a non-conflicting schedule. In this paper, we present such a mechanism which allows wireless sensors to choose a time interval for transmission, which is not interfering or causing collisions with other transmissions. In our solution, we do not assume any hierarchical organization in the network and all operation is localized. We empirically show that our localized algorithm is successful within a factor 2 of the minimum necessary time slots in random networks; well in range of the expected (worst case) factor 3-approximation of known first-fit algorithms. Our algorithm assures similar minimum distance between simultaneous transmissions as CSMA(/CD)-based approaches.