A Hybrid Energy Efficient Protocol for Mobile Ad Hoc Networks

We proposed an energy conservation technique called Location Based Topology Control with Sleep Scheduling for ad hoc networks. It uses the feature of both topology control approach and power management approach. Like the topology control approach, it attempts to reduce the transmission power of a node, which is determined from its neighborhood location information. A node goes to sleep state based on the traffic condition as that of power management approach. In the proposed scheme, a node goes to sleep state only when its absence does not create local partition in its neighborhood. We preformed extensive simulation to compare the proposed scheme with existing ones. Simulation results show that the energy consumption is lower with increase in the network lifetime and higher throughput in the proposed scheme

Techniques to enhance the lifetime of mobile ad hoc networks

Devices in Mobile Ad Hoc Networks (MANETs) are mostly powered by battery. Since the battery capacity is fixed, some techniques to save energy at the device level or at the protocol stack should be applied to enhance the MANETs lifetime. In this thesis, we have proposed a few energy saving approaches at the network layer, and MAC layer. First, we proposed a routing technique, to which the following metrics are built into: (i) node lifetime, (ii) maximum limit on the number of connections to a destination, and (iii) variable transmission power. In this technique, we consider a new cost metric which takes into account the residual battery power and energy consumption rate in computing the lifetime of a node. To minimize the overutilization of a node, an upper bound is set on the number of connections that can be established to a destination. The proposed technique is compared with AODV [1] and LER [2]. It outperforms AODV and LER in terms of network lifetime. Next, a technique called Location Based Topology Control with Sleep Scheduling (LBTC) is proposed. It uses the feature of both topology control approach in which the transmission power of a node is reduced, and power management approach in which nodes are put to sleep state. In LBTC the transmission power of a node is determined from the neighborhood location information. A node goes to sleep state only when: (i) it has no traffic to participate, and (ii) its absence does not create a local partition. LBTC is compared with LFTC [3] and ANTC [4]. We observed that the network lifetime in LBTC is substantially enhanced. A framework for post-disaster communication using wireless ad hoc networks is proposed. This framework includes: (i) a multi-channel MAC protocol, (ii) a node-disjoint multipath routing, and (iii) a distributed topology aware scheme. Multi-channel MAC protocol minimizes the congestion in the network by transmitting data through multiple channels. Multipath routing overcomes the higher energy depletion rate at nodes associated with shortest path routing. Topology aware scheme minimizes the maximum power used at node level. Above proposals, taken together intend to increase the network throughput, reduce the end-to-end delay, and enhance the network lifetime of an ad hoc network deployed for disaster response

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

PSA: The Packet Scheduling Algorithm for Wireless Sensor Networks

The main cause of wasted energy consumption in wireless sensor networks is packet collision. The packet scheduling algorithm is therefore introduced to solve this problem. Some packet scheduling algorithms can also influence and delay the data transmitting in the real-time wireless sensor networks. This paper presents the packet scheduling algorithm (PSA) in order to reduce the packet congestion in MAC layer leading to reduce the overall of packet collision in the system The PSA is compared with the simple CSMA/CA and other approaches using network topology benchmarks in mathematical method. The performances of our PSA are better than the standard (CSMA/CA). The PSA produces better throughput than other algorithms. On other hand, the average delay of PSA is higher than previous works. However, the PSA utilizes the channel better than all algorithms