Cross-layer design of multi-hop wireless networks

MULTI -hop wireless networks are usually defined as a collection of nodes equipped with radio transmitters, which not only have the capability to communicate each other in a multi-hop fashion, but also to route each others’ data packets. The distributed nature of such networks makes them suitable for a variety of applications where there are no assumed reliable central entities, or controllers, and may significantly improve the scalability issues of conventional single-hop wireless networks. This Ph.D. dissertation mainly investigates two aspects of the research issues related to the efficient multi-hop wireless networks design, namely: (a) network protocols and (b) network management, both in cross-layer design paradigms to ensure the notion of service quality, such as quality of service (QoS) in wireless mesh networks (WMNs) for backhaul applications and quality of information (QoI) in wireless sensor networks (WSNs) for sensing tasks. Throughout the presentation of this Ph.D. dissertation, different network settings are used as illustrative examples, however the proposed algorithms, methodologies, protocols, and models are not restricted in the considered networks, but rather have wide applicability. First, this dissertation proposes a cross-layer design framework integrating a distributed proportional-fair scheduler and a QoS routing algorithm, while using WMNs as an illustrative example. The proposed approach has significant performance gain compared with other network protocols. Second, this dissertation proposes a generic admission control methodology for any packet network, wired and wireless, by modeling the network as a black box, and using a generic mathematical 0. Abstract 3 function and Taylor expansion to capture the admission impact. Third, this dissertation further enhances the previous designs by proposing a negotiation process, to bridge the applications’ service quality demands and the resource management, while using WSNs as an illustrative example. This approach allows the negotiation among different service classes and WSN resource allocations to reach the optimal operational status. Finally, the guarantees of the service quality are extended to the environment of multiple, disconnected, mobile subnetworks, where the question of how to maintain communications using dynamically controlled, unmanned data ferries is investigated

Performance Analysis of Multiple Access Techniques for LTE system under Symbol Error Rate (SER) Calculation

In the recent years, so many technologies in multiple access trends have influenced the field of Wireless Sensor Networks in significant ways. Various trends are readily available technology of ubiquitous wireless sensor networks as well as wireless communication networks and progress in the development of two multiple access techniques are compared in this scenario: the OFDMA and SC-FDMA. The OFDMA and SC-FDMA transceivers are modeled and simulated considering both the interleaved and localized subcarriers mapping schemes. WSNs have the potentiality to connect the physical world with the virtual world by forming a network of sensor nodes. To prolong the networklsquo;s hop in terms of single and two hop using both techniques should be used in the sensor nodes. The minimization of computing and storage platforms as well as the development of novel micro sensors and sensor materials with high reliability force encourages technology in research on WSN. In this paper, we will proposed the field of multipath routing in wireless sensor networks, and mainly focus on the technology of SER of WSNs