An Opportunistic Large Array (OLA) is a form of cooperative diversity in which a large group of simple, inexpensive relays operate without any mutual coordination, but naturally fire together in response to the energy received from a single source or another OLA. The main contributions of this thesis are the introduction of two OLA-based routing protocols: OLA Concentric Routing Algorithm (OLACRA), which is an upstream routing algorithm suitable for static wireless sensor networks (WSNs), and OLA Routing On-Demand (OLAROAD), which is a robust reactive routing scheme suitable for mobile ad hoc networks (MANETs). In fixed multi-hop wireless sensor networks with a single sink, where energy conservation is often a concern, simulations of the new algorithms show as much as 80% of the transmit energy required to broadcast data can be saved, relative to existing OLA-based broadcasting approaches. In MANETs, where robustness of the routes is an important performance indicator, OLAROAD-based cooperative routes last much longer compared to their state-of-art multi-hop non-cooperative transmission (CT)-based counterparts. However, OLACRA and OLAROAD have higher node participation, and thereby lower throughput, in comparison with the non-CT schemes. To improve the throughput, and thereby bandwidth utilization, the properties of uplink OLAs and their suppression regions are carefully studied. Based on the observations, Hop-Optimized OLACRA (HOLA), which is a variant of OLACRA, and has the maximum bandwidth utilization amongst all the OLA unicast schemes studied, is proposed. HOLA routes have bandwidth utilization comparable to non-CT schemes, but a much lower (~10 dB less) transmit power per node. The last section of this thesis treats the MAC design for OLA-based networks. In contrast to non-CT networks, a 802.11-based RTS/CTS MAC scheme is shown to reduce the reliability in OLA unicast schemes. A distributed cluster-head-based MAC scheme for channel reservation and OLA Size Adaptation Mechanism for link repair/maintenance are proposed for OLA-based networks. The performances of these protocols are shown to be comparable to a non-CT multihop scheme using the RTS/CTS/DATA/ACK handshake-based link layer design.

Wireless and Mobile (WAM) networks have been evolving and extending their reach to more aspects of human activity for years. As such, networks have been deployed in wider and broader physical range and circumstances, so that end-to-end contemporaneous connectivity is no longer guaranteed. To address this connectivity challenge, recent research work on Disruption Tolerant Network (DTN) paradigm uses intermediate nodes to store data while waiting for transfer opportunities towards the destination. However, this work differs from conventional research work in WAM, e.g., Mobile Ad hoc Network (MANET) routing, since the connectivity assumptions are so different. In this thesis, we present the WAM Continuum framework which aims to provide a unified treatment of wireless and mobile networks. The framework is based on the construction of a WAM continuum that defines the space of networks and a corresponding formalism by which one can group related WAMs into classes that map into design and operational regimes. We show a specific instantiation of this framework that classifies networks according to their path properties and apply it to networks described by traces from both real platforms and synthesized mobility models. Effect of introducing controllable node mobility, e.g., message ferrying, is quantitatively evaluated in our study. We extend this framework in a manner that enables the classification of a WAM's energy "sufficiency" depending on a combination of the network connectivity properties, available energy, and power management scheme. As another extension under the same WAM continuum framework, this thesis studies the interaction of mobile computation collaboration and underlying network connectivity characteristics. Classification results from our framework indicate that heterogeneous connectivity may exist in WAM networks. In such cases, protocols from different routing paradigms need to work together to provide effective data communication. We focus on integration of MANET routing and message ferrying in clustered DTNs. A hybrid routing approach is developed in which both MANET routing and message ferrying are used to explore available connectivity in clusters via gateway nodes. Different data aggregation as well as transmission scheduling algorithms are proposed. To achieve better performance, we also study the ferry route design problem in the clustered DTNs and develop three route design algorithms. This thesis work also includes our experience to address challenges associated with new data communication requirements in oil field operations at remote areas. Backed up by a comprehensive measurement study of long range data links provided by satellite and cellular services, we develop a WAM network where multiple data links are jointly used to achieve an effective data communication solution in the challenged environment.

Most mobile nodes are operated using batteries, protocols which conserve energy are of interest. The Dynamic Directional Power Control Protocol (DDPC) is a protocol that dynamically varies the energy used in directional transmission to increase the battery life of the transmitter without sacrificing connectivity with the receiver. The advantage of DDPC is that it takes into account the remaining battery power of a node before changing its transmission power. DDPC can achieve a higher network lifetime when compared to a network where nodes use a fixed transmit power level. Meanwhile DDPC dynamically reduces the energy consumed by a node in transmission. It can also reach nodes far from the transmitter by using directional antennas.

In the past decade, the development of wireless communication technologies has made the use of the Internet ubiquitous. With the increasing number of new inventions and applications using wireless communication, more interference is introduced among wireless devices that results in limiting the capacity of wireless networks. Many approaches have been proposed to improve the capacity. One approach is to exploit multiple channels by allowing concurrent transmissions, and therefore it can provide high capacity. Many available, license-exempt, and non-overlapping channels are the main advantages of using this approach. Another approach that increases the network capacity is to adjust the transmission power; hence, it reduces interference among devices and increases the spatial reuse. Integrating both approaches provides further capacity. However, without careful transmission power control (TPC) design, the network performance is limited. The first part of this thesis tackles the integration to efficiently use multiple channels with an effective TPC design in a distributed manner. We examine the deficiency of uncontrolled asymmetrical transmission power in multi-channel ad hoc wireless networks. To overcome this deficiency, we propose a novel distributed transmission power control protocol called the distributed power level (DPL) protocol for multi-channel ad hoc wireless networks. DPL allocates different maximum allowable power values to different channels so that the nodes that require higher transmission power are separated from interfering with the nodes that require lower transmission power. As a result, nodes select their channels based on their minimum required transmission power to reduce interference over the channels. We also introduce two TPC modes for the DPL protocol: symmetrical and asymmetrical. For the symmetrical mode, nodes transmit at the power that has been assigned to the selected channel, thereby creating symmetrical links over any channel. The asymmetrical mode, on the other hand, allows nodes to transmit at a power that can be lower than or equal to the power assigned to the selected channel. In the second part of this thesis, we propose the multi-channel MAC protocol with hopping reservation (MMAC-HR) for multi-hop ad hoc networks to overcome the multi-channel exposed terminal problem, which leads to poor channel utilization over multiple channels. The proposed protocol is distributed, does not require clock synchronization, and fully supports broadcasting information. In addition, MMAC-HR does not require nodes to monitor the control channel in order to determine whether or not data channels are idle; instead, MMAC-HR employs carrier sensing and independent slow channel hopping without exchanging information to reduce the overhead. In the last part of this thesis, a novel multi-channel MAC protocol is developed without requiring any change to the IEEE 802.11 standard known as the dynamic switching protocol (DSP) based on the parallel rendezvous approach. DSP utilizes the available channels by allowing multiple transmissions at the same time and avoids congestion because it does not need a dedicated control channel and enables nodes dynamically switch among channels. Specifically, DSP employs two half-duplex interfaces: One interface follows fast hopping and the other one follows slow hopping. The fast hopping interface is used primarily for transmission and the slow hopping interface is used generally for reception. Moreover, the slow hopping interface never deviates from its default hopping sequence to avoid the busy receiver problem. Under single-hop ad hoc environments, an analytical model is developed and validated. The maximum saturation throughput and theoretical throughput upper limit of the proposed protocol are also obtained.

An opportunistic large array (OLA) is a form of cooperative diversity in which a large group of simple, inexpensive relays or forwarding nodes operate without any mutual coordination, but naturally fire together in response to energy received from a single source or another OLA. When used for broadcast, OLAs form concentric rings around the source, and have been shown to use less energy than conventional multi-hop protocols. This simple broadcasting scheme, which is already known, is called Basic OLA. The OLA Concentric Routing Algorithm (OLACRA), which is our contribution, takes advantage of the concentric ring structure of broadcast OLAs to limit flooding on the upstream connection. By limiting the node participation, OLACRA saves over 80% of the energy compared to Basic OLA, without requiring GPS, individual node addressing, or inter-node interaction. This thesis analyzes the performance of OLACRA over 'deterministic channels' where transmissions are on non-faded orthogonal channels and on 'diversity channels' where transmissions are on Rayleigh flat fading limited orthogonal channels. The performance of diversity channels is shown to approach the deterministic channel at moderate orders of diversity. Enhancements to OLACRA to further improve its efficiency by flooding in the initial upstream level and limiting the downlink 'step sizes' are also considered. The protocols are tested using Monte Carlo evaluation.

Distributed systems like e-commerce and e-market places, peer-to-peer networks, social networks, and mobile ad hoc networks require cooperation among the participating entities to guarantee the formation and sustained existence of network services. The reliability of interactions among anonymous entities is a significant issue in such environments. The distributed entities establish connections to interact with others, which may include selfish and misbehaving entities and result in bad experiences. Therefore, trustworthiness evaluation using trust management techniques has become a significant issue in securing these environments to allow entities decide on the reliability and trustworthiness of other entities, besides it helps coping with defection problems and stimulating entities to cooperate. Recent models on evaluating trustworthiness in distributed systems have heavily focused on assessing trustworthiness of entities and isolate misbehaviours based on single trust metrics. Less effort has been put on the investigation of the subjective nature and differences in the way trustworthiness is perceived to produce a composite multidimensional trust metrics to overcome the limitation of considering single trust metric. In the light of this context, this thesis concerns the evaluation of entities’ trustworthiness by the design and investigation of trust metrics that are computed using multiple properties of trust and considering environment. Based on the concept of probabilistic theory of trust management technique, this thesis models trust systems and designs cooperation techniques to evaluate trustworthiness in mobile ad hoc networks (MANETs). A recommendation based trust model with multi-parameters filtering algorithm, and multidimensional metric based on social and QoS trust model are proposed to secure MANETs. Effectiveness of each of these models in evaluating trustworthiness and discovering misbehaving nodes prior to interactions, as well as their influence on the network performance has been investigated. The results of investigating both the trustworthiness evaluation and the network performance are promising.

La technique MIMO (Multiple-Input Multiple-Output) est l’une des techniques de base qui offre une diversité spatiale. Elle associe plusieurs antennes à l’émission et à la réception. En plus de la diversité spatiale, le système MIMO permet d’augmenter le gain de multiplexage sans avoir besoin de plus de bande passante ou de puissance d’émission. Cependant, la technique MIMO a des limites liées au coût d’installation de plusieurs antennes sur un terminal, et a l’écart minimal exigé entre les antennes. La communication coopérative a été proposée comme une technologie alternative, dans laquelle la diversité spatiale peut être réalisée en coordonnant plusieurs nœuds qui sont proches géographiquement pour former des réseaux d’antennes virtuelles. La coopération permet de lutter contre l’instabilité du canal radio et de faire face aux phénomènes qui le perturbent comme les évanouissements, les bruits, ou les interférences. Elle permet aussi d’améliorer les performances du système en termes de débit global, d’énergie consommée et d’interférences, etc. Dans le cadre des communications coopératives, nous avons proposé deux protocoles MAC coopératifs dans le contexte des réseaux ad hoc. La première proposition est le protocole RACT (Rate Adaptation with Cooperative Transmission). Ce protocole combine la coopération avec un mécanisme d’adaptation de débit. Lorsqu’un lien entre une source et une destination subit de mauvaises conditions de canal, une station relais est sélectionnée dans le voisinage des deux nœuds de sorte que la liaison directe à faible débit de transmission soit remplacée par un lien à deux sauts avec un débit de données plus élevé. La sélection du meilleur relais est fondée sur un processus de contention distribué. La procédure ne nécessite aucune connaissance de la topologie et aucune communication entre les relais potentiels. Lorsque la qualité de la liaison directe est bonne et que la transmission coopérative n’est pas nécessaire, le protocole fonctionne comme un mécanisme d’adaptation de débit. L’adaptation de débit de données est également réalisée sans aucune signalisation supplémentaire. La sélection du meilleur relais et l’adaptation de débit sont fondés sur des mesures instantanées du canal pour s’adapter aux conditions dynamiques du canal radio. Dans le but d’améliorer davantage les performances du système, nous avons proposé notre deuxième protocole MAC coopératif PRACT (Power and Rate Adaptation with Cooperative Transmission). Ce protocole combine un mécanisme d’adaptation de puissance et de débit (TPRC : Transmit Power and Rate Control) avec un mécanisme de coopération. C’est en cela que cette contribution se distingue des solutions proposées dans la littérature. Notre objectif avec cette contribution est d’atteindre une efficacité d’énergie pour la transmission des données tout en augmentant le débit global du réseau. PRACT propose d’ajuster dynamiquement la puissance et le débit de transmission en s’adaptant aux variations de la qualité du canal radio. Cela permet de gagner davantage dans l’énergie économisée. En outre, le contrôle de puissance, réduit les interférences et augmente la réutilisation spatiale entre cellules ad hoc adjacentes en utilisant la même fréquence de transmission. L’idée de base du protocole est de permettre à chaque nœud dans le réseau ad hoc de créer une table avec les combinaisons puissance-débit optimales, en se fondant seulement sur les spécifications de la carte réseau, à savoir, les débits de transmission possible et la consommation en énergie de la carte. Avec la connaissance des qualités des liens obtenue grâce à l’échange des trames de contrôle et en recherchant dans la table puissance-débit, les nœuds choisissent la stratégie de transmission la plus adaptée pour chaque transmission de trames de données, ainsi que le mode de transmission (direct ou coopératif). / MIMO (Multiple-Input Multiple-Output) technology is one of the basic techniques that offer a spatial diversity. It combines multiple antennas for transmission and reception. In addition to spatial diversity, MIMO can increase the multiplexing gain without requiring more bandwidth or transmit power. However, the MIMO technology has limitations related to the cost of installing multiple antennas on a terminal, and to the minimum distance required between antennas. The cooperative communication has been proposed as an alternative technology, in which the spatial diversity can be achieved by coordinating multiple nodes that are geographically close to form virtual antenna arrays. Cooperation helps to fight against the instability of the radio channel and deal with phenomena that disturb this channel like fading, noise or interference. It also improves system performance in terms of overall throughput, energy consumption and interference, etc. In the context of cooperative communications, we proposed two MAC protocols in the context of cooperative ad-hoc networks. The first proposal is the RACT (Rate Adaptation with Cooperative Transmission) protocol. This protocol combines cooperation with a rate adaptation mechanism. When a link between a source and a destination suffers from poor channel conditions, a relay station is selected in the neighborhood of the two nodes so that the direct low data-rate link is replaced by a two-hop link with a higher data-rate. Selecting the best relay is based on a distributed contention process. The procedure requires no knowledge of the topology and no communication between the potential relay. When the quality of the direct link is good enough and the cooperative transmission is not necessary, the protocol operates as a rate adaptation mechanism. The data rate adaptation is also performed without any additional signaling. Both the best relay selection and the rate adaptation is based only on the instantaneous channel measurements to adapt to the dynamic conditions of the radio channel. In order to further improve the system performance, we proposed our second cooperative MAC protocol PRACT (Power and Rate Adaptation with Cooperative Transmission). This protocol combines a power and rate control mechanism (TPRC: Transmit Power and Rate Control) with a mechanism for cooperation, this feature distinguishes this contribution from the solutions proposed in the literature. Our objective with this contribution is to achieve energy efficiency for data transmission while increasing the overall throughput of the network. PRACT proposes to dynamically adjust dynamically the power and the transmission rate to adapt to the radio channel quality variations. This way more energy can be saved. In addition, the power control reduces interference and increases the spatial reuse between adjacent ad-hoc cells using the same channel transmission frequency. The basic idea of the protocol is to allow each node in the network to create a table with the best power-rate combinations, based only on the specifications of the network card, namely the possible transmission rates, transmit power levels and the power consumption of the card. With the knowledge of the qualities of links obtained through the exchange of the control frames and looking up in the power-rate table, the nodes choose the most suitable transmission strategy, for each data frame transmission, and the transmission mode (direct or cooperative).

Orientador: Prof. Dr. João Henrique Kleinschmidt / The dissemination of wireless networks will enable the interconnection of every type of device, creating what is called the Internet of Things. In this concept, objects with great potential for the deployment of new applications are the automotive vehicles that will form mobile networks known as VANETs (Vehicular Ad Hoc Networks). These networks are particularly sensitive to information security issues, because, besides the common threats, one deliberate cybernetic attack or functional anomaly can result in traffic accidents. Due to its specific characteristics, the establishment of trust in VANET networks requires the introduction of additional not traditional measures of information security. This MsC thesis proposes a centralized mechanism of vehicular reputation based on the concept of certified reputation. In the scheme, vehicles communicate with other network participants providing its digital certificate, which includes the reputation level safely stored by the vehicle. Decision-making mechanisms in the receiving vehicles are responsible for judging whether messages are true or false, based on the reputation of the issuers nodes. Periodically, vehicles must connect to the certification authorities and central control of traffic to update their reputation level, which is determined centrally by validating their behavior in participation and communication of events on the network. Quantitative analysis of simulated scenarios showed that the adequate combination of the reputation mechanism with a vehicular decision mechanism presents better results than without a reputation system, considering the existence of false messages and attacks on the network. This way, the proposed system proved its effectiveness in reducing the risks of anomalous or malicious behavior in a VANET network. / Dissertação (mestrado) - Universidade Federal do ABC, Programa de Pós-Graduação em Engenharia da Informação, 2015. / A disseminação das redes sem fio possibilitará a interconexão de qualquer tipo de dispositivo, criando o que se denomina de Internet das Coisas. Neste conceito, um dos objetos com grande potencial para o desenvolvimento de aplicações são os veículos automotores, que constituirão redes móveis conhecidas como VANETs (Vehicular Ad Hoc Networks). Estas redes são particularmente sensíveis às questões relacionadas à segurança da informação, pois, além das ameaças comuns, um ataque cibernético deliberado ou anomalias de funcionamento podem levar a acidentes viários. Devido às suas características particulares, o estabelecimento de confiança nas redes VANET exigirá a aplicação de medidas adicionais não tradicionais de segurança da informação. Esta dissertação apresenta uma proposta de mecanismo centralizado de reputação veicular baseada no conceito de reputação certificada. No esquema, os veículos se comunicam com os demais participantes da rede fornecendo seu certificado digital, que inclui o nível de reputação armazenado de forma segura pelo veículo. Mecanismos de decisão nos veículos receptores são responsáveis por julgar se as mensagens são verdadeiras ou falsas, baseando-se na reputação dos nós de comunicação emitentes. Periodicamente, os veículos devem entrar em contato com as autoridades certificadoras e de controle central de tráfego para atualizar seu nível de reputação, que é determinado centralmente pela validação de seu comportamento de participação e comunicação dos eventos na rede. A análise quantitativa de cenários simulados mostrou que a combinação adequada do mecanismo de reputação com um mecanismo de decisão veicular apresenta um total de decisões certas superior a de sistemas sem reputação, considerando a existência de mensagens falsas e ataques ao sistema. Desta forma, o sistema proposto mostrou sua eficácia em reduzir os riscos de comportamentos anômalos ou maliciosos em uma rede VANET.

La multiplication de l'usage des équipements connectables à un réseau sans fil tels que les smartphones ou les objets connectés peut être mise à profit pour construire des réseaux reposant sur des communications de proximité : les appareils communiquent directement entre eux, sans le support d'une infrastructure centrale. On parle de réseau ad hoc. Ce type de réseau sans infrastructure est exploité dans de nombreux domaines comme le militaire ou la gestion de catastrophes naturelles. Pour certains cas d'utilisation, le passage à l'échelle, c'est-à-dire la capacité à fonctionner avec la croissance de la taille du réseau, est une propriété indispensable. Dans cette thèse, nous nous intéressons à la problématique du routage sous l'aspect du passage à l'échelle. Le routage est la fonction responsable de l'acheminement des données au sein du réseau. Pour cela, des informations de contrôle sont échangées entre les nœuds du réseau. Mais le trafic associé à ces échanges peut être un frein pour passer à l'échelle. Afin de le réduire, nous proposons d'agréger les informations concernant des nœuds géographiquement proches. Dans un premier temps, nous mettons en place une structuration de la zone de déploiement du réseau en régions hiérarchiques. Ces régions servent d'agrégateur de nœuds à travers un adressage de ces derniers selon les régions auxquelles ils appartiennent. Par la suite, nous proposons un protocole de routage combinant les approches topologique et géographique. Il s'agit, pour un nœud donné, de maintenir des routes menant, d’une part, vers d'autres nœuds dans un voisinage proche et, d'autre part, vers des zones géographiques de plus en plus étendues au fur et à mesure de l'éloignement. Cette dernière propriété est obtenue en profitant de la structuration hiérarchique précédente des zones d'agrégation. Les résultats montrent la faculté de notre proposition à monter à grande échelle par rapport aux protocoles de routage ad hoc classique et aussi sa capacité à adresser les problèmes propres aux protocoles de routage purement géographique. / The widespread use of wireless devices such as smartphones and connected objects leads to an increasing emergence of infrastructure-less networks relying on device-to-device communication: ad hoc networks. Applications of this type of network vary widely from military operations to emergency situations. Scalability is a key property for some use cases involving a large number of devices, also called nodes. We mean by scalability, the ability of the network to increase in size without drastic loss of performance and with a cost-effective network maintenance. In this thesis, we focus on the scalability from a routing perspective. Routing handles the delivery of data packets from a source to a destination across the network. This is achieved by the exchange of information between nodes. The corresponding traffic may represent a break for scalability in presence of numerous nodes. In this work, we propose an aggregation of routing information. First, we partition the deployment area into smaller hierachical regions based on geographical coordinates. Nodes are assigned hierachical address depending on the regions they are located in. Then, we propose a mixed topological and geographical-based routing protocol. A node maintains precise routing information to other nodes in close proximity and geographically aggregate information for nodes at greater distances. Regions are the units of nodes aggregation. The further the nodes are, the larger the regions referring to them are. The results show that our proposition outperforms regular ad hoc routing in terms of scalability and addresses more efficiently geographical routing-related issues compared to classical geographical routing.

Submitted by Clebson Anjos (clebson.leandro54@gmail.com) on 2016-02-16T22:43:34Z No. of bitstreams: 1 arquivototal.pdf: 6316800 bytes, checksum: 0b88bad394fd98379d16f9b515a3f984 (MD5) / Made available in DSpace on 2016-02-16T22:43:34Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 6316800 bytes, checksum: 0b88bad394fd98379d16f9b515a3f984 (MD5) Previous issue date: 2015-08-31 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / The communication between robots is essential and of great interest in the robotics research eld. It is from it that the robots can discover and pass on information about obstacles in their way, pass on to the other robots information about a target that other robot can not detect, determine together which is the best route to follow, among others, until the goals are achieved. The major di culty in the context where robot communication exists in an Ad Hoc network is distancing the robots from each other. So that one of them for example, may migrate to another area leaving their initial formation, completing a speci c task and return to the starting point, in addition to distancing the whole formation of robots from a central computer. By distancing a robot from the limits imposed by other means will entail a loss of signal compromising communication between them. This way, knowing a wireless network coverage area where robots will be connected is an important process for the implementation of a system of communication between robots. The aim of this work is to demonstrate the feasibility of expanding the coverage area of a wireless network, to be used in multi-robot systems, of a formation of robots that use a Real Time Database (RTDB) in multilayer networks that using the IEEE 802.11 and 802.15.4, analyzing the behavior of this expansion in relation to connectivity of robots, coverage area and interference in wireless networks. According to the performed experiments, the results demonstrate the robustness and reliability of the proposed scenario and it was shown that the use of multilayer networks provides a greater range in the coverage area of a robot training. / A comunicação entre robôs é tarefa fundamental e de grande importância na robótica. É a partir dela que robôs conseguem descobrir e repassar informações sobre obstáculos encontrados no caminho, transmitir informações sobre um alvo que outro robô não consiga detectar ou determinar, em conjunto com outros robôs, a melhor rota a ser seguida, entre outros. Uma das grandes dificuldades, no contexto em que se tem a comunicação de robôs em uma rede sem o, está em distanciá-los. Um deles, por exemplo, pode migrar para uma outra área a m de realizar uma tarefa específi ca, distanciando-se, assim, da sua formação inicial e ultrapassando o limiar de cobertura de rede. Ao distanciar um robô do outro, os limites conferidos pelo meio acarretarão uma perda de sinal comprometendo a comunicação entre eles. Deste modo, conhecer a área de cobertura de uma rede sem o onde robôs estarão conectados é um processo importante para a implantação de um sistema de comunicação entre robôs. Este trabalho propõe expansão da área de cobertura de uma rede sem o, a ser utilizada em sistemas multi-robôs, usando um Middleware de Base de Dados em Tempo Real - RTDB, em redes multicamadas que utilizam os padrões IEEE 802.11 e 802.15.4, analisando o comportamento dessa expansão em relação a conectividade dos robôs, área de cobertura e de interferência de Redes Sem Fio. Os resultados obtidos demonstram a robustez e con fiabilidade do cenário proposto e de acordo com os experimentos realizados, comprovou-se que o uso de redes multicamadas proporciona um maior alcance na área de cobertura de uma formação de robôs.