Wi-Fi in Ad Hoc Mode: A Measurement Study
PERCOM '04 Proceedings of the Second IEEE International Conference on Pervasive Computing and Communications (PerCom'04)
Wireless Communications & Mobile Computing - Special Issue: Emerging WLAN Apllications and Technologies
Collision Detection based on Transmission Time Information in IEEE 802.11 Wireless LAN
PERCOMW '06 Proceedings of the 4th annual IEEE international conference on Pervasive Computing and Communications Workshops
Proceedings of the 12th annual international conference on Mobile computing and networking
Exploiting the capture effect for collision detection and recovery
EmNets '05 Proceedings of the 2nd IEEE workshop on Embedded Networked Sensors
Optimal tradeoff between exposed and hidden nodes in large wireless networks
Proceedings of the ACM SIGMETRICS international conference on Measurement and modeling of computer systems
Optimal physical carrier sense in wireless networks
Ad Hoc Networks
Reuse efficiency of wireless access networks under physical carrier sense: A Markovian analysis
Journal of Parallel and Distributed Computing
Performance modeling and analysis of IEEE 802.11 wireless networks with hidden nodes
Proceedings of the 16th ACM international conference on Modeling, analysis & simulation of wireless and mobile systems
Joint Transmit Power Control and Rate Adaptation for Wireless LANs
Wireless Personal Communications: An International Journal
An Efficient and Fair Strategy for Radio Resources Allocation in Multi-radio Wireless Mesh Networks
Wireless Personal Communications: An International Journal
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Multi-hop ad hoc networks suffer from the "hidden" and "exposed" node problems which diminish aggregate network throughput. While there are various approaches to mitigating these problems, in this work we focus exclusively on the role of physical carrier sensing (PCS). Specifically, tuning the PCS threshold leads to a trade-off between the hidden and exposed cases; reducing one typically increases the other, implying the existence of an optimal PCS threshold setting maximizes the aggregate network throughput. The contributions of this work are two-fold: i. We develop an analytical model to determine the optimal PCS threshold for a homogeneous network with constant link distances and show that setting the carrier sensing range close to the interference range is a robust close-to-optimal setting for network optimization in many scenarios. As an extension to more pragmatic network topologies with non-uniform link distances, a rate-to-link allocation scheme is proposed based on rendering the interference range equal for all links that allows a single carrier sense range to be used for the whole network. ii. The above suggests the need for on-line adaptation of tunable PCS threshold in general. The proposed algorithm is based on the key concept of loss differentiation (LD), which disambiguates the cause of packet loss event due to link layer interference (hidden terminals) and collisions respectively. Extensive simulation results show that the proposed PCS adaptations make the PCS threshold converge to its optimal value and thus outperform schemes without PCS adaptation.