3 research outputs found
Topology-transparent distributed multicast and broadcast scheduling in mobile ad hoc networks
Transmission scheduling is a key problem in mobile ad hoc networks. Many transmission scheduling algorithms have been proposed to maximize the spatial reuse and minimize the time-division multiple-access (TDMA) frame length in mobile ad hoc networks. Most algorithms are dependent on the exact network topology and cannot adapt to the dynamic topology in a mobile wireless network. To overcome this limitation, several topology-transparent scheduling algorithms have been proposed. The slots are assigned to guarantee that there is at least one collision-free time slot in each frame. In this paper, we consider multicast and broadcast, and propose a novel topology-transparent distributed scheduling algorithm. Instead of guaranteeing at least one collision-free transmission, the proposed algorithm guarantees one successful transmission exceeding a given probability, and achieves a much better average throughput. The simulation results show that the performance of our proposed algorithm is much better than the conventional TDMA and other existing algorithms in most cases. © 2012 IEEE.published_or_final_versio
Energy-delay region of low duty cycle wireless sensor networks for critical data collection
Session: Sensor networksThe Conference program's website is located at http://ita.ucsd.edu/workshop/14/talksWe investigate the trade-off between energy consumption and delay for critical data collection in low duty cycle wireless sensor networks, where a causality constraint exists for routing and link scheduling. We characterize the energy-delay region (E-D region) and formulate a combinatorial optimization problem to determine the link scheduling with the causality constraint. A new multiple-degree ordered (MDO) coloring method is proposed to solve this problem with near-optimal delay performance. The impacts of many system parameters on the ED region are evaluated by extensive simulation, providing an insightful frame of reference for design of critical data collection wireless sensor networks.postprin
Towards Optimal Distributed Node Scheduling in a Multihop Wireless Network through Local Voting
In a multihop wireless network, it is crucial but challenging to schedule
transmissions in an efficient and fair manner. In this paper, a novel
distributed node scheduling algorithm, called Local Voting, is proposed. This
algorithm tries to semi-equalize the load (defined as the ratio of the queue
length over the number of allocated slots) through slot reallocation based on
local information exchange. The algorithm stems from the finding that the
shortest delivery time or delay is obtained when the load is semi-equalized
throughout the network. In addition, we prove that, with Local Voting, the
network system converges asymptotically towards the optimal scheduling.
Moreover, through extensive simulations, the performance of Local Voting is
further investigated in comparison with several representative scheduling
algorithms from the literature. Simulation results show that the proposed
algorithm achieves better performance than the other distributed algorithms in
terms of average delay, maximum delay, and fairness. Despite being distributed,
the performance of Local Voting is also found to be very close to a centralized
algorithm that is deemed to have the optimal performance