A Novel Communications Protocol Using Geographic Routing for Swarming UAVs Performing a Search Mission

This research develops the UAV Search Mission Protocol (USMP) for swarming UAVs and determines the protocol\u27s effect on search mission performance. It is hypothesized that geographically routing USMP messages improves search performance by providing geography-dependent data to locations where it impacts search decisions. It is also proposed that the swarm can use data collected by the geographic routing protocol to accurately determine UAV locations and avoid sending explicit location updates. The hypothesis is tested by developing several USMP designs that are combined with the Greedy Perimeter Stateless Routing (GPSR) protocol and a search mission swarm logic into a single network simulation. The test designs use various transmission power levels, sensor types and swarm sizes. The simulation collects performance metrics for each scenario, including measures of distance traveled, UAV direction changes, number of searches and search concentration. USMP significantly improves mission performance over scenarios without inter-UAV communication. However, protocol designs that simply broadcast messages improve search performance by 83% in total searches and 20% in distance traveled compared to geographic routing candidates. Additionally, sending explicit location updates generates 3%-6% better performance per metric versus harvesting GPSR\u27s location information

3D Geographical routing in wireless sensor networks

In this paper, we present a novel 3D geographical routing algorithm (3DGR) that makes use of the position information to route packets from sources to destinations with high path quality and reliability. The locality and high scalability of this algorithm make it suitable for wireless sensor networks. It provides high adaptability to changes in topology and recovery of link failures which increases its reliability. We also incorporate the battery-aware energy efficient schemes to increase the overall lifetime of the network. To reduce latency, a method of keeping a small record of recent paths is used. We also show that location errors still result in good performance of our algorithm while the same assumptions might yield to bad performance or even complete failures in others. Simulation results show that the power consumption and delay using 3DGR are close to optimal obtainable based on full knowledge of the network

A novel Ferry Assisted Greedy Perimeter Stateless Routing Protocol (FA-GPSR) for Ad-hoc networks in remote locations

Network functionalities play a major role in the connectivity and routing in an Ad-hoc networks because end user devices must contribute in routing and therefore maintain connectivity. In dynamic environments with mobile nodes, routing becomes very challenging; this challenge becomes even more burdensome if a network is deployed in larger areas. Therefore, in order to avoid centralisation and bottlenecks, routing algorithms in Ad-hoc networks should not depend on any specific node. Furthermore, these algorithms should be able to support routing in sparse topologies when the density of the nodes is very low in a large deployment area. The rationale behind this research project stems from the lack of sufficiently effective solutions for wireless networks deployed in large areas where the node's mobility creates what is called the Loosely Coupled Nodes Problem. Therefore, this gap in knowledge needs to be addressed by developing a novel and scalable routing protocol, which can utilise application characteristics to stabilise routing between loosely coupled nodes in a large deployment area. This research proposes a new routing protocol to address this gap by increasing the number of packets delivered to their final destinations in an Ad-hoc networks. As another gap, very few current approaches deal with realistic situations, based on real-life case scenarios, in order to evaluate and enhance the accuracy of their Ad-hoc network protocols, and thus they cannot accurately approximate common real world environments [1]. Therefore, this project addresses research issues directly linked to evaluation of protocols and architectures in use cases and applications in real life scenarios. The novel routing algorithm, Ferry-Assisted Greedy Perimeter Stateless Routing (FA-GPSR), proposed in this thesis demonstrates the benefits of extracting information from the application to support communication between the nodes in the network topology. In addition, this approach highlights the advantages and disadvantages of the efficiency and reliability of communication in open large areas of deployment. A simulation model of the proposed algorithm has been implemented and its features investigated through simulation runs. The communication between nodes in the topology show that FA-GPSR outperforms the other routings in terms of packet delivery ratio, especially in sparse networks, where the density of nodes is low. The mobility of the destination nodes affected the packets delivery ratio by decreasing the ratio, compared to other cases because of the changes in the location and node velocity. By increasing the number of packets and source nodes, FA-GPSR outperformed the other algorithms because of the efficient use of the patrol node (ferry). Thus, the comparison of FA-GPSR to these algorithms supports the conclusion that FA-GPSR is suitable for use in large open areas with the effect of node density and packet load

Robotic Wireless Sensor Networks

In this chapter, we present a literature survey of an emerging, cutting-edge, and multi-disciplinary field of research at the intersection of Robotics and Wireless Sensor Networks (WSN) which we refer to as Robotic Wireless Sensor Networks (RWSN). We define a RWSN as an autonomous networked multi-robot system that aims to achieve certain sensing goals while meeting and maintaining certain communication performance requirements, through cooperative control, learning and adaptation. While both of the component areas, i.e., Robotics and WSN, are very well-known and well-explored, there exist a whole set of new opportunities and research directions at the intersection of these two fields which are relatively or even completely unexplored. One such example would be the use of a set of robotic routers to set up a temporary communication path between a sender and a receiver that uses the controlled mobility to the advantage of packet routing. We find that there exist only a limited number of articles to be directly categorized as RWSN related works whereas there exist a range of articles in the robotics and the WSN literature that are also relevant to this new field of research. To connect the dots, we first identify the core problems and research trends related to RWSN such as connectivity, localization, routing, and robust flow of information. Next, we classify the existing research on RWSN as well as the relevant state-of-the-arts from robotics and WSN community according to the problems and trends identified in the first step. Lastly, we analyze what is missing in the existing literature, and identify topics that require more research attention in the future

Performance Evaluation of Ad Hoc Routing in a Swarm of Autonomous Aerial Vehicles

This thesis investigates the performance of three mobile ad hoc routing protocols in the context of a swarm of autonomous unmanned aerial vehicles (UAVs). It is proposed that a wireless network of nodes having an average of 5.1774 log n neighbors, where n is the total number of nodes in the network, has a high probability of having no partitions. By decreasing transmission range while ensuring network connectivity, and implementing multi-hop routing between nodes, spatial multiplexing is exploited whereby multiple pairs of nodes simultaneously transmit on the same channel. The proposal is evaluated using the Greedy Perimeter Stateless Routing (GPSR), Optimized Link State Routing (OLSR), and Ad hoc On-demand Distance Vector (AODV) routing protocols in the context of a swarm of UAVs using the OPNET network simulation tool. The first-known implementation of GPSR in OPNET is constructed, and routing performance is observed when routing protocol, number of nodes, transmission range, and traffic workload are varied. Performance is evaluated based on proportion of packets successfully delivered, average packet hop count, and average end-to-end delay of packets received. Results indicate that the routing protocol choice has a significant impact on routing performance. While GPSR successfully delivers 50% more packets than OLSR, and experiences a 53% smaller end-to-end delay than AODV when routing packets in a swarm of UAVs, increasing transmission range and using direct transmission to destination nodes with no routing results in a level of performance not achieved using any of the routing protocols evaluated

RESOURCE ALLOCATION AND EFFICIENT ROUTING IN WIRELESS NETWORKS

In wireless networks, devices (nodes) are connected by wireless links. An important issue is to set up high quality (high bandwidth) and efficient routing paths when one node wants to send packets to other nodes. Resource allocation is the foundation to guarantee high quality connections. In addition, it is critical to handle void areas in order to set up detour-free paths. Moreover, fast message broadcasting is essential in mobile wireless networks. Thus, my research includes dynamic channel allocation in wireless mesh networks, geographic routing in Ad Hoc networks, and message broadcasting in vehicular networks. The quality of connections in a wireless mesh network can be improved by equip- ping mesh nodes with multi-radios capable of tuning to non-overlapping channels. The essential problem is how to allocate channels to these multi-radio nodes. We develop a new bipartite-graph based channel allocation algorithm, which can improve bandwidth utilization and lower the possibility of starvation. Geographic routing in Ad Hoc networks is scalable and normally loop-free. However, traditional routing protocols often result in long detour paths when holes exist. We propose a routing protocol-Intermediate Target based Geographic Routing (ITGR) to solve this problem. The novelty is that a single forwarding path can be used to reduce the lengths of many future routing paths. We also develop a protocol called Hole Detection and Adaptive Geographic Routing, which identifies the holes efficiently by comparing the length of a routing path with the Euclidean distance between a pair of nodes. We then set up the shortest path based on it. Vehicles play an important role in our daily life. During inter-vehicle communication, it is essential that emergency information can be broadcast to surrounding vehicles quickly. We devise an approach that can find the best re-broadcasting node and propagate the message as fast as possible

Local Area Dynamic Routing Protocol: a Position Based Routing Protocol for MANET

A Mobile Ad Hoc Network (MANET) comprises mobile nodes (MNs), equipped with wireless communications devices; which form a temporary communication network without fixed network infrastructure or topology. The characteristics of MANET are: limited bandwidth; limited radio range; high mobility; and vulnerability to attacks that degrade the signal to noise ratio and bit error rates. These characteristics create challenges to MANET routing protocols. In addition, the mobility pattern of the MNs also has major impact on the MANET routing protocols. The issue of routing and maintaining packets between MNs in the mobile ad hoc networks (MANETs) has always been a challenge; i.e. encountering broadcast storm under high node density, geographically constrained broadcasting of a service discovery message and local minimum problem under low node density. This requires an efficient design and development of a lightweight routing algorithm which can be handled by those GPS equipped devices. Most proposed location based routing protocols however, rely on a single route for each data transmission. They also use a location based system to find the destination address of MNs which over time, will not be accurate and may result in routing loop or routing failure. Our proposed lightweight protocol, ‘Local Area Network Dynamic Routing’ (LANDY) uses a localized routing technique which combines a unique locomotion prediction method and velocity information of MNs to route packets. The protocol is capable of optimising routing performance in advanced mobility scenarios, by reducing the control overhead and improving the data packet delivery. In addition, the approach of using locomotion prediction, has the advantage of fast and accurate routing over other position based routing algorithms in mobile scenarios. Recovery with LANDY is faster than other location protocols, which use mainly greedy algorithms, (such as GPRS), no signalling or configuration of the intermediate nodes is required after a failure. The key difference is that it allows sharing of locomotion and velocity information among the nodes through locomotion table. The protocol is designed for applications in which we expect that nodes will have access to a position service (e.g., future combat system). Simulation results show that LANDY`s performance improves upon other position based routing protocols

Study of Obstacle effect on the GPSR protocol and a Novel Intelligent Greedy Routing protocol for VANETs

In recent years, connected vehicle technologies have been developed by automotive companies, academia, and researchers as part of Intelligent Transportation Systems (ITS). This group of stakeholders continue to work on these technologies to make them as reliable and cost-effective as possible. This attention is because of the increasing connected vehicles safety-related, entertainment, and traffic management applications, which have the potential to decrease the number of road accidents, save fuel and time for millions of daily commuters worldwide. Vehicular Ad-Hoc Network (VANET), which is a subgroup of Mobile Ad-Hoc Network (MANET), is being developed and implemented in vehicles as the critical structure for connected vehicles applications. VANET provides a promising concept to reduce the number of fatalities caused by road accidents, to improve traffic efficiency, and to provide infotainment. To support the increasing number of safety-related applications, VANETs are required to perform reliably. Since VANETs promise numerous safety applications requiring time-bound delivery of data packets, it is also necessary to replicate real-world scenarios in simulations as accurately as possible. Taking into account the effect of realistic obstacles while simulating a variety of case scenarios increases the reliability of the tested routing protocol to appropriately perform in real-world situations. It also exposes routing protocols to possible vulnerabilities caused by obstacles. Nevertheless, it is not uncommon for researchers to omit real-world physical layer communication hurdles in simulation-based tests, including not considering the effect of obstacles on their routing protocol performance evaluation simulations. Consequently, the performance of these protocols is usually overestimated and do not support in real-world environment. Failure to account for obstacle effects overstate the network performance. In this thesis, a framework for measuring obstacle effects on routing protocols is defined. We also propose, a new routing protocol based on the traditional Greedy Perimeter Stateless Routing (GPSR) protocol called Intelligent Greedy Routing (IGR) protocol. The proposed IGR protocol considers a parameter called $Receptivity$ to chose the next hop in a route. We implemented the new protocol using the Simulation of Urban Mobility (SUMO) and the Network Simulator (NS-3). An analysis of Packet Delivery Ratio (PDR), End-to-End Delay (E2ED) and Mean Hop count with the assumption that nodes (vehicles) are moving in various topologies is presented in this thesis. The study presented here gives a general idea of the effects of obstacles on the Greedy Perimeter Stateless Routing (GPSR) protocol considering multiple realistic scenarios such as Urban, Residential and Highway. In addition, we compare the performance of GPSR and the new IGR protocols with the presence of obstacles considering various topologies. The new proposed IGR protocol performs better compared to the traditional GPSR for all the investigated metrics