Probabilistic approaches to the design of wireless ad hoc and sensor networks

The emerging wireless technologies has made ubiquitous wireless access a reality and enabled wireless systems to support a large variety of applications. Since the wireless self-configuring networks do not require infrastructure and promise greater flexibility and better coverage, wireless ad hoc and sensor networks have been under intensive research. It is believed that wireless ad hoc and sensor networks can become as important as the Internet. Just as the Internet allows access to digital information anywhere, ad hoc and sensor networks will provide remote interaction with the physical world. Dynamics of the object distribution is one of the most important features of the wireless ad hoc and sensor networks. This dissertation deals with several interesting estimation and optimization problems on the dynamical features of ad hoc and sensor networks. Many demands in application, such as reliability, power efficiency and sensor deployment, of wireless ad hoc and sensor network can be improved by mobility estimation and/or prediction. In this dissertation, we study several random mobility models, present a mobility prediction methodology, which relies on the analysis of the moving patterns of the mobile objects. Through estimating the future movement of objects and analyzing the tradeoff between the estimation cost and the quality of reliability, the optimization of tracking interval for sensor networks is presented. Based on the observation on the location and movement of objects, an optimal sensor placement algorithm is proposed by adaptively learn the dynamical object distribution. Moreover, dynamical boundary of mass objects monitored in a sensor network can be estimated based on the unsupervised learning of the distribution density of objects. In order to provide an accurate estimation of mobile objects, we first study several popular mobility models. Based on these models, we present some mobility prediction algorithms accordingly, which are capable of predicting the moving trajectory of objects in the future. In wireless self-configuring networks, an accurate estimation algorithm allows for improving the link reliability, power efficiency, reducing the traffic delay and optimizing the sensor deployment. The effects of estimation accuracy on the reliability and the power consumption have been studied and analyzed. A new methodology is proposed to optimize the reliability and power efficiency by balancing the trade-off between the quality of performance and estimation cost. By estimating and predicting the mass objects\u27 location and movement, the proposed sensor placement algorithm demonstrates a siguificant improvement on the detection of mass objects with nearmaximal detection accuracy. Quantitative analysis on the effects of mobility estimation and prediction on the accuracy of detection by sensor networks can be conducted with recursive EM algorithms. The future work includes the deployment of the proposed concepts and algorithms into real-world ad hoc and sensor networks

Detecting Multiple Waveforms of Telecommunication Generations for Wireless Disaster Recovery Networks

This thesis proposes a simple algorithm to detect multiple waveforms of telecommunication generation technologies that minimize power consumption of Mobile cognitive radio base station (MCRBS) due to limited source of power in the disaster area. MCRBS is an alternative to soon recover cellular networks after the main base station (BTS) are damaged by disaster causing power outage. MCRBS has two modes of (i) {Normal mode}, with regular seperated frequency, and (ii) Ad-hoc mode with a single frequency network. MCRBS in Ad-hoc mode requires capability of detecting multiple waveforms of telecommunication generation technologies of the second (2G), third (3G), forth (4G), and fifth (5G) to recover the networks. The Normal mode assumes that disaster area is small such that each generation can work properly based on their allocated frequency, while the Ad-hoc mode assumes that disaster area is large, such that frequency of 5G may need to be shifted to lower frequency to serve victim users located far away from the MCRBS. This thesis aims to provide header detection capability for both two modes using combination of cross-correlation and capture effect technique for better accuracy. Four different header sequences are following the standard of all telecommunication generation technologies. To complete the analysis, this thesis also evaluates header detection both in synchronous and unsynchronous transmission, in terms of mean square error (MSE) under additive white Gaussian noise (AWGN) and frequency--flat Rayleigh fading channels. This thesis found that MSE below 10^-3 at average SNR more than 0~dB is achievable for: (a) header detection for single user of 2G, 3G, 4G, and 5G header sequences, and (b) header detection for multi-generation on synchronous transmission and unsynchronous transmission. These results confirm that MCRBS with Ad-hoc mode is possible in detecting multiple waveforms using low frequency covering long range to provide connections for more victims located far away from the MCRBS. These results are expected to provide contributions to the development of wireless technologies for disaster and recovery networks in Indonesia

Efficient Discovery Protocol for Ubiquitous Communication in Wireless Environment

Nowadays, according to the advances of the wireless network technologies and also mobile computing devices the concept of ubiquitous computing environments has become a considerable research area. Ubiquitous computing environment means an environment which is saturated by elements or devices with capacities of computing and communication. So, there are a lot of ways to develop and employ applications in such environment as infrastructure, but the most effective and general one is using service advertisements, service discovery and service remote invocation. In an Ad-hoc network which its devices make an ubiquitous computing environment, every device as a server node can announce various applications as services in the environment and at the same time every device is able to listen to the network interface and be aware of surrounding services and invoke the remote services.A mechanism which is needed to recognize surrounding services is called service discovery, this mechanism also clears how to advertise services, and invoke them. Type and method of discovery procedures play the critical role in quality and efficiency of services in ubiquitous environments. Because of these properties (small and mobile) there is a serious limitation for the resources of devices specially power resource. The problem is that the most of service discovery protocols are not effective for wireless Ad- Hoc networks and ubiquities environments, efficiency in case of service quality and power consumption. In this research a new mechanism and algorithm is designed to improve current wireless service discovery protocols. Analysis of the results has shown that the designed mechanism in most of the comparative parameters such as speed of service delivery, power consumption, and coverage of the services will act much better than the current discovery protocols. The proposed solution is compared with (directory based and directory-less based) of discovery protocols in ubiquitous environment in three states: mobile nodes, mobile and static nodes, and static nodes. It can be derived that the proposed model obtains fewer messages around 52% while maintain the same rate of service discovery and false rate of service discovery. The reduction of the number of posts per request coupled with the fact that devices with greater time availability transmit more responses in the proposed model, it can be concluded that energy consumption in devices with more restrictions will be decreased

A Review of the Energy Efficient and Secure Multicast Routing Protocols for Mobile Ad hoc Networks

This paper presents a thorough survey of recent work addressing energy efficient multicast routing protocols and secure multicast routing protocols in Mobile Ad hoc Networks (MANETs). There are so many issues and solutions which witness the need of energy management and security in ad hoc wireless networks. The objective of a multicast routing protocol for MANETs is to support the propagation of data from a sender to all the receivers of a multicast group while trying to use the available bandwidth efficiently in the presence of frequent topology changes. Multicasting can improve the efficiency of the wireless link when sending multiple copies of messages by exploiting the inherent broadcast property of wireless transmission. Secure multicast routing plays a significant role in MANETs. However, offering energy efficient and secure multicast routing is a difficult and challenging task. In recent years, various multicast routing protocols have been proposed for MANETs. These protocols have distinguishing features and use different mechanismsComment: 15 page

Applying named data networking in mobile ad hoc networks

This thesis presents the Name-based Mobile Ad-hoc Network (nMANET) approach to content distribution that ensure and enables responsible research on applying named data networking protocol in mobile ad-hoc networks. The test framework of the nMANET approach allows reproducibility of experiments and validation of expected results based on analysis of experimental data. The area of application for nMANETs is the distribution of humanitarian information in emergency scenarios. Named-Data Networking (NDN) and ad-hoc mobile communication allow exchange of emergency information in situations where central services such as cellular towers and electric systems are disrupted. The implemented prototype enables researchers to reproduce experiments on content distribution that consider constraints on mobile resources, such as the remaining power of mobile devices and available network bandwidth. The nMANET framework validates a set of experiments by measuring network traffic and energy consumption from both real mobile devices and those in a simulated environment. Additionally, this thesis presents results from experiments in which the nMANET forwarding strategies and traditional wireless services, such as hotpost, are analysed and compared. This experimental data represents the evidence that supports and validates the methodology presented in this thesis. The design and implementation of an nMANET prototype, the Java NDN Forwarder Daemon (JNFD) is presented as a testing framework, which follows the principles of continuous integration, continuous testing and continuous deployment. This testing framework is used to validate JNFD and IP-based technologies, such as HTTP in a MANET using the OLSR routing protocol, as well as traditional wireless infrastructure mode wireless. The set of experiments executed, in a small network of Android smart-phones connected in ad-hoc mode and in a virtual ad-hoc network simulator show the advantages of reproducibility using nMANET features. JNFD is open source, all experiments are scripted, they are repeatable and scalable. Additionally, JNFD utilises real GPS traces to simulate mobility of nodes during experiments. This thesis provides experimental evidence to show that nMANET allows reproducibility and validation of a wide range of future experiments applying NDN on MANETs

Spectrum and Energy Efficient Medium Access Control for Wireless Ad Hoc Networks

The increasingly growing number of mobile devices and volume of mobile data traffic necessitate establishing an effective self-organizing wireless ad hoc network to efficiently utilize radio spectrum and energy. The transmissions time and bandwidth should be dynamically coordinated based on instantaneous traffic load of the links in the network. Energy consumption in a mobile device can be reduced by putting the radio interface into a sleep mode. However, the mobile device cannot receive incoming data packets in the sleep mode. Thus, awake and sleep times of radio interfaces should be carefully planned to avoid missing incoming packets. In a wireless network, links that are far apart in distance can simultaneously transmit using the same bandwidth without interfering reception at destination nodes. Concurrent transmissions should be properly scheduled to maximize spatial spectrum utilization. Also, the transmission power level of each link should be optimized to enhance spectrum and energy efficiencies. First, we present a new energy-efficient medium access control (MAC) scheme for a fully connected wireless ad hoc network. Energy consumption is reduced by periodically putting radio interfaces in the sleep mode and by reducing transmission collisions. The network throughput and average packet transmission delay are also improved because of lower collision and contention overhead. The proposed MAC scheme can achieve energy saving for realtime traffic which requires a low packet transmission delay. An analytical model is established to evaluate the performance of the proposed MAC scheme. Analytical and simulation results demonstrate that the proposed scheme has a significantly lower energy consumption, achieves higher throughput, and has a lower packet transmission delay in comparison with existing power saving MAC protocols. Second, we present a novel distributed MAC scheme based on dynamic space-reservation to effectively coordinate transmissions in a wireless ad hoc network. A set of coordinator nodes distributed over the network area are employed to collect and exchange local network information and to periodically schedule links for transmission in a distributed manner. For each scheduled transmission, a proper space area around the receiver node is reserved to enhance spatial spectrum reuse. Also, the data transmission times are deterministic to minimize idle-listening radio interface energy consumption. Simulation results demonstrate that the proposed scheme achieves substantially higher throughput and has significantly lower energy consumption in comparison with existing schemes. We study joint scheduling and transmission power control in a wireless ad hoc network. We analyze the asymptotic joint optimal scheduling and transmission power control, and determine the maximum spectrum and energy efficiencies in a wireless network. Based on the asymptotic analysis, we propose a novel scheduling and transmission power control scheme to approach the maximum spectrum efficiency, subject to an energy consumption constraint. Simulation results show that the proposed distributed scheme achieves 40% higher throughput than existing schemes. Indeed, the scheduling efficiency of our proposed scheme is about 70% of the asymptotic optimal scheduling and transmission power control. Also, the energy consumption of the proposed scheme is about 20% of the energy consumed using existing MAC protocols. The proposed MAC, scheduling and transmission power control schemes provide effective spectrum sharing and energy management for future wireless hotspot and peer-to-peer communication networks. The presented asymptotic analysis determines the maximum spectrum and energy efficiencies in a wireless network and provides an effective means to efficiently utilize spectrum and energy resources based on network traffic load and energy consumption constrains