Power Aware Routing in Mobile Ad Hoc Networks

The era of big data has begun and an enormous amount of real-time data is used for the risk analysis of various industrial applications. However, a technical challenge exists in gathering real-time big data in a complex indoor industrial environment. Indoor wireless sensor networks (WSNs) technology can overcome this limitation by collecting the big data generated from source nodes and transmitting them to the data center in real time. In this study, typical residence, office, and manufacturing environments were chosen. The signal transmission characteristics of an indoor WSN were obtained by analyzing the test data. According to these characteristics, a real-time big data gathering (RTBDG) algorithm based on an indoor WSN is proposed for the risk analysis of industrial operations. In this algorithm, sensor nodes can screen the data collected from the environment and equipment according to the requirements of risk analysis. Clustering data transmission structure is then established on the basis of the received signal strength indicator (RSSI) and residual energy information. Experimental results show that RTBDG not only uses the limited energy of network nodes efficiently, but also balances the energy consumption of all nodes. In the near future, the algorithm will be widely applied to risk analysis in different industrial operations.

A Real-Time Big Data Gathering Algorithm Based on Indoor Wireless Sensor Networks for Risk Analysis of Industrial Operations

The mobility and resource limitation of nodes are the critical factors that affect the performance of Mobile AD hoc network (MANET). The mobility of nodes will affect the stability of links, and the limitation of node resources will lead to congestion, so it is very difficult to design a routing protocol that supports quality of service (QoS) in MANET. Especially in the scenario of high-speed node movement, frequent link interruption will damages QoS performance, so it is necessary to design MANET routing protocol that can adapt to network topology changes to support QoS. In this paper, we propose a Topological change Adaptive Ad hoc On-demand Multipath Distance Vector (TA-AOMDV) routing protocol, which can adapt to high-speed node movement to support QoS. In this protocol, a stable path selection algorithm is designed, which not only takes node resources (residual energy, available bandwidth and queue length) as the path selection parameters, but also considers the link stability probability between nodes. Furthermore, in order to adapt to the rapid change of topology, link interrupt prediction mechanism is integrated into the protocol, which updates the routing strategy based on periodic probabilistic estimates of link stability. Different scenarios with node speed in the range of 10-50m/s, data rate in the range of 4-40kbps and number of nodes in the range of 10-100 are simulated on NS2 platform. Our results show that the QoS metrics (packet delivery rate, end-to-end delay, and throughput) of the proposed protocol are significantly improved when the node speed is higher than 30m/s although it is slightly better when the node speed is lower than 30m/s. Our on-demand multipath routing protocol demonstrates high potential to support QoS for high-speed MANET.

An Adaptive on-Demand Multipath Routing Protocol With QoS Support for High-Speed MANET

A new clustering protocol for energy harvesting-wireless sensor networks

Mobile ad-hoc network (MANET) plays a significant role in the field of communication. Due to the dynamic movement of nodes, the network infrastructure is frequently changed. All nodes have the capacity to configure themselves and are communicated either directly through some intermediate nodes based on signal strength or through multi-hop routing. However, selection of the intermediate nodes will increase the routing overload in the route discovery procedure. Destination nodes are selected using intermediate nodes for broadcasting data packets with link scalability. The previous works for this problem have limitations such as they are not flexible to deliver the Quality of Service in the network model, and the possibility of packet delivery is less. In this paper, we propose Fault-Tolerant Disjoint Multipath Distance Vector Routing Algorithm (FD-AOMDV) that sprints path discovery phase with a reduced amount of delay. It finds disjoint paths in a way that routing overloads decrease considerably. FD-AOMDV can increase the scalability by reducing the routing overload when the latest route is established. Moreover, owing to the mobility of the node in MANETs, subsequent breakages of a link will cause the active path disconnection and also enlarge the routing overload. The simulation results prove that the proposed work reduces the routing overload, decreases the end-to-end delay, and reduces the packet delivery ratio compared with AOMDV and ZD-AOMDV on Network Simulator 2.

FD-AOMDV: fault-tolerant disjoint ad-hoc on-demand multipath distance vector routing algorithm in mobile ad-hoc networks

AOMDV protocol is designed for highly dynamic ad hoc networks where link failures and route breaks occur frequently. However, the rapidly changing topology makes the limited power nodes exhaust rapidly, which makes the network split early with the decrease of the networks lifetime. A new multipath protocol called Multipath Routing Protocol for Networks Lifetime Maximization in Ad-Hoc Networks (MRNLM) is proposed based on AOMDV. The protocol sets energy threshold to optimize the forwarding mechanism. At the same time it builds an energy-cost function and uses the function as the criterion for multiple path selection. In transmission phase, we use a novelty method called "data transmission in multiple paths one by one" to balance the energy in multiple paths. The performance is compared between MRNLM and AOMDV by NS2. It is shown that MRNLM is able to balance the energy of the networks with the lifetime increase at least 14% under different nodes pause time. For different packet rate, the lifetime increases no less than 35%.

Multipath Routing Protocol for Networks Lifetime Maximization in Ad-Hoc Networks

Routing protocol plays a role of great importance in the performance of wireless sensor networks (WSNs). A centralized balance clustering routing protocol based on location is proposed for WSN with random distribution in this paper. In order to keep clustering balanced through the whole lifetime of the network and adapt to the non-uniform distribution of sensor nodes, we design a systemic algorithm for clustering. First, the algorithm determines the cluster number according to condition of the network, and adjusts the hexagonal clustering results to balance the number of nodes of each cluster. Second, it selects cluster heads in each cluster base on the energy and distribution of nodes, and optimizes the clustering results to minimize energy consumption. Finally, it allocates suitable time slots for transmission to avoid collision. Simulation results demonstrate that the proposed protocol can balance the energy consumption and improve the network throughput and lifetime significantly.

https://link.springer.com/content/pdf/10.1007%2Fs11277-013-1033-z.pdf

A Centralized Balance Clustering Routing Protocol for Wireless Sensor Network

Much research efforts have been devoted to develop protocols based on one criterion, majority of the routing protocols consider energy conservation or minimum bandwidth. But only one factor could not guarantee the requirements for quality of the service (Qos) in ad hoc networks. In this paper, a route protocol called Qos-AOMDV is proposed which considers two criteria. Both the balance of the route and power conservation is considered. Qos-AOMDV is based on cross-layer design, which could cooperate in sharing network-status information in different layers while maintaining the layers' separation to optimize overall network performance. Both the information in network layer and data link layer are combined to make a general criterion, so that it could satisfy the dynamics of ad hoc network. In the path selection phase, the destination nodes do not reply route request (RREQ) immediately. Route reply (RREP) is carried out based on the general cost criterion. In transmission phase, data is transmitted in multiple paths one by one to balance the energy and the traffic loads in multiple paths. It is shown by simulation that QoS-AOMDV could achieve remarkable improvements in terms of end to end delay, throughput and lifetime as compared to AOMDV.

QoS Multipath Routing Protocol Based on Cross Layer Design for Ad hoc Networks

With the development of mobile communication, adaptive algorithms are often chosen in real time process because of their high speed. However, existing adaptive algorithms are not suitable in frequency selective fading channels. In this paper, an improved adaptive synchronization algorithm is proposed for the application under frequency selective fading channels. A novel correlation function is proposed to reduce the effect of intersymbol interference, which only requires coarse channel length estimation. A gate value is also used to combine both the constant and decreasing step size methods; thus, the proposed algorithm is capable of distinguishing between tracking and convergent stages, and then choosing the right step size. Furthermore, an accelerating method is introduced to make the algorithm track faster, i.e. making the algorithm move more steps if it searches in the same direction as the last step. It is shown that the mean square errors of time and frequency offset estimates can be reduced to 0.9243 and 0.003 respectively even when the channel length estimate is not good, which totally satisfies Beek's requirement for synchronization. Simulation also shows that it takes only 10-20 symbols for the proposed algorithm to track the change of channel delay. Compared with the existing adaptive algorithm, the proposed algorithm has a higher accuracy with a higher tracking speed, and the proposed algorithm also has advantages over some nonadaptive algorithms with higher accuracy and lower computational complexity.

Adaptive OFDM synchronization algorithm in frequency selective fading channels

Cognitive radio (CR) is applied to solve spectrum scarcity. Although the auction theory and learning algorithm have been discussed in previous works, their combination is not yet researched in the distributed CR networks, where secondary users (SUs) can occupy several channels simultaneously by assuming that one channel can be accessed by at most one SU. A parallel repeated auction scheme is proposed to solve resource allocation in multi-user multi-channel distributed spectrum-overlay CR networks. A novel bid scheme in the light of the first-price sealed auction is designed to balance the system utility and allocation fairness. The proposed auction scheme can be developed based on a learning algorithm and be applied to the scenarios where the cooperation among SUs is unavailable. Under the assumption of limited entry budget, SUs can directly decide whether or not to participate in spectrum auction by comparing the possible bid with access threshold which can be applied into situations that SUs have different transmit power. Theoretical analysis and simulation results show that, compared with original myopic scheme and original genie-aided scheme, the proposed auction scheme can obtain a considerable improvement in efficiency and fairness, especially with adequate available resources.

Yonghong Kuo

Papers

Multipath Routing Protocol for Networks Lifetime Maximization in Ad-Hoc Networks

A Centralized Balance Clustering Routing Protocol for Wireless Sensor Network

QoS Multipath Routing Protocol Based on Cross Layer Design for Ad hoc Networks

Adaptive OFDM synchronization algorithm in frequency selective fading channels

A Parallel Repeated Auction for Spectrum Allocation in Distributed Cognitive Radio Networks