Pasquale Pace

Enabling IoT interoperability through opportunistic smartphone-based mobile gateways

In the near future, all our everyday things and objects will be both connected to the Internet and equipped with enough sensing, acting and processing capabilities to exploit the full potential benefits of the so called Internet of Things (IoT) paradigm. Even the simplest objects will become smart because they will be interconnected to other objects to share and collect data from the environments in which they are placed thus paving the way to novel application services, computing and communication scenarios.In this context, interoperability among different standards and communication technologies is still a significant challenge that we have started to address by proposing a smartphone-based mobile gateway acting as a flexible and transparent interface between different IoT devices and the Internet. The presented unified, high-level and extendible software architecture supports opportunistic IoT devices discovery, control and management coupled with data processing, collection and diffusion functionalities.A specific testbed on common smartphones with different hardware and software capabilities was deployed to evaluate the real feasibility of the designed solution measuring the system performance in terms of energy consumption, memory and CPU usage in high and low load scenarios. According to the obtained results, the implemented software architecture for multi-standard and multi-technology interoperation presents a reduced use of hardware resources in front of a relatively high energy consumption value, mostly due to the simultaneously active radio interfaces combined with a small battery capacity, that limits the smartphone lifetime. Nevertheless, the presented general approach is still remarkable because this latter aspect will most likely be exceeded, in a short time, thanks to daily technological advancements in both batteries and radio interfaces.

Cloud-based Activity-aaService cyber–physical framework for human activity monitoring in mobility

Abstract This paper proposes Activity as a Service (Activity-aaService), a full-fledged cyber–physical framework to support community, on-line and off-line human activity recognition and monitoring in mobility. Activity-aaService is able to address the current lack of Cloud-Assisted Body Area Networks platforms and applications supporting monitoring and analysis of human activity for single individuals and communities. Activity-aaService is built atop the BodyCloud platform so enabling efficient BSN-based sensor data collection and local processing (Body-side), high performance computing of collected sensor data and data storing on the Cloud (Cloud-side), workflow-based programming of data analysis (Analyst-side), and advanced visualization of results (Viewer-side). Specifically, it provides specific, powerful and flexible programming abstractions for the rapid prototyping of efficient human activity-oriented applications. The effectiveness of the proposed framework has been demonstrated through the development of several prototypes related to physical activity monitoring, step counting, physical energy estimation, automatic fall detection, and smart wheelchair support. Finally, performance evaluation of the proposed framework at the Body-side of the activity classification has been carried out by analyzing processing load, data transmission time, CPU usage, memory footprint, and battery consumption using four heterogeneous mobile devices representing low, medium and high performance mobile platforms.

An integrated satellite-HAP-terrestrial system architecture: resources allocation and traffic management issues

This paper explains the potential role of an integrated satellite-HAP (high altitude platform)-terrestrial system. A simple and suitable architecture is presented. The proposed architecture consists of three layers: the terrestrial layer, HAP layer and GEO layer. The terrestrial layers terminals, within the same HAP coverage area, have to use a HAP transponder and HAP master control station (HMCS) to send and receive data amongst themselves. Moreover the HAP gateway stations (HGTW) guarantees communications among users belonging to different HAP coverage areas using the GEO satellite links. Since high quality multimedia application support is a key objective for upcoming communication systems, this paper investigates the issues related to this topic. In order to guarantee an adequate quality of service to these kinds of service requires an efficient resources allocation and traffic management algorithm to be implemented inside the HMCS and HGTW stations.

Efficient real-time multimedia connections handling over DVB-RCS satellite system

The main objective of this work is the proposal of a new connection admission control (CAC) algorithm guaranteeing both a high connection multiplexing level and, in particular, a good quality of service (QoS) for real-time multimedia traffic sources mapped over the service classes of the DVB-RCS standard. In this paper, we suppose a DVB-RCS system architecture using a multi-spot beam geostationary satellite with regenerative payload. We also suppose IP traffic to be carried, in return and forward directions, via DVB/MPEG-2 traffic streams instead of to the obsolete ATM encapsulation. Simulation results show that, even if the real time multimedia connections are more sensitive to the delay jitter, the agreed QoS is always guaranteed, even when the system load increases; moreover, using the proposed algorithm, a high system throughput is obtainable.

A multi-technology location-aware wireless system for interactive fruition of multimedia contents

Nowadays, due to the increasing demands of the fast-growing consumer electronics (CEs) market, more powerful mobile consumer devices are being introduced continuously. With this evolution of CEs technologies, many sophisticated electronic applications starts to be developed and applied to context and location aware scenarios. This paper proposes a flexible communication architecture well suited for the interactive fruition of historical and artistic contents throughout a wireless network infrastructure. The designed system and the implemented low cost testbed integrate different communication technologies such as Wi-Fi, Bluetooth and GPS with the aim of offering, in a transparent and reliable way, a mixed set of different multimedia and augmented reality (AR) contents to mobile users equipped with CEs devices. This communication architecture represents a first step to provide a network support to context-aware applications pushing the ubiquitous computing paradigm into the reality.

POTENTIALITIES OF USRP-BASED SOFTWARE DEFINED RADAR SYSTEMS

Software Deflned Radar is the latest trend in radar development. To handle enhanced radar signal processing techniques, advanced radars need to be able of generating various types of waveforms, such as frequency modulated or phase coded, and to perform multiple functions. The adoption of a Software Deflned Radio system makes easier all these abilities. In this work, the implementation of a Software Deflned Radar system for target tracking using the Universal Software Radio Peripheral platform is discussed. For the flrst time, an experimental characterization in terms of radar application is performed on the latest Universal Software Radio Peripheral NI2920, demonstrating a strongly improved target resolution with respect to the flrst generation platform.

STEM-mesh: Self-organizing mobile cognitive radio network for disaster recovery operations

In this paper, we address the problem of re-establishing the network connectivity in post-disaster scenarios, where the original wireless infrastructure has been partitioned into multiple network fragments (called islands), operating on different frequencies. To this purpose, we propose the utilization of swarms of dedicated repairing units, called Stem-Nodes (SNs). SNs are provided with Cognitive Radio (CR) and self-positioning capabilities, in order to offer maximum reconfigurability in terms of mobility and wireless technologies supported. Moreover, swarms of SNs can self-organize into STEM-Mesh structure, that works as a dynamic backbone to connect heterogeneous islands using different technologies (e.g. Wi-Fi, Wi-MAX, etc). In this paper, we present three contributions pertaining to STEM-Mesh: (i) we describe a distributed motion control scheme (based on virtual springs approach) that enables SNs to self-organize into dynamic STEM-Mesh structures, (ii) we introduce a discovery scheme, through which SNs can explore the scenario in both spatial and frequency domains, and possibly connect the islands to the STEM-Mesh backbone and (iii) we validate the correctness of the proposed scheme, by verifying the optimal placements of the SNs composing the STEM-Mesh on a simplified scenario (e.g. chain topology). Finally, we evaluate through Omnet++ simulations the ability of STEM-Mesh to maximally re-establish connectivity on partitioned network scenarios.

Software defined radar: synchronization issues and practical implementation

The present work is focused on Software Defined Radar - (SDR) paradigm, which gives a more versatile solution when compared to classical radar systems. Thanks to this new system model, most of the fundamental operations, such as signal generation, filtering, up and down conversion, are easily implemented via software. The objective of this paper is to show the main issues related to the design of an effective Software Defined Radar device. Specifically, we will discuss and face the synchronization issues existing between a received and a transmitted signal when an open source hardware, namely the Universal Software Radio Peripheral (USRP), is considered.

AR-TP: An Adaptive and Responsive Transport Protocol for Wireless Mesh Networks

Wireless meshing has been envisioned as the economically viable networking paradigm to build up broadband and large-scale wireless commodity networks. Several different mesh network architectures have been conceived by both industry and academia; however many issues on the deployment of efficient and fair transport protocols are still open. In this paper, an adaptive and responsive transport protocol (AR- TP) is proposed for WMNs in order to fairly allocate the network resources among multiple flows, while minimizing the performance overhead. Compared to the classical end-to-end rate control mechanisms, an hop-by-hop congestion control approach is designed to keep track of dynamic multi-hop network characteristics in a responsive manner. In addition, a coarse-grained end-to-end reliability algorithm is integrated with the proposed hop-by-hop congestion control mechanism to provide packet level reliability at the transport layer. Performance evaluation via extensive simulation experiments show that the AR-TP protocol achieves high performance in terms of network throughput and fairness.

Challenges and Issues in Designing Architectures and Protocols for Wireless Mesh Networks

Wireless Mesh Network (WMN) is a promising wireless technology for several emerging and commercially interesting applications, e.g., broadband home networking, community and neighborhood networks, coordinated network management, intelligent transportation systems. It is gaining significant attention as a possible way for Internet service providers (ISPs) and other endusers to establish robust and reliable wireless broadband service access at a reasonable cost. WMNs consist of mesh routers and mesh clients as shown in Fig. 1. In this architecture, while static mesh routers form the wireless backbone, mesh clients access the network through mesh routers as well as directly meshing with each other. Different from traditional wireless networks, WMN is dynamically selforganized and self-configured. In other words, the nodes in the mesh network automatically establish and maintain network connectivity. This feature brings many advantages for the end-users, such as low up-front cost, easy network maintenance, robustness, and reliable service coverage. In addition, with the use of advanced radio technologies, e.g., multiple radio interfaces and smart antennas, network capacity in WMNs is increased significantly. Moreover, the gateway and bridge functionalities in mesh routers enable the integration of wireless mesh networks with various existing wireless networks, such as wireless sensor networks, wireless-fidelity (Wi-Fi), and WiMAX [3]. Consequently, through an integrated wireless mesh network, the end-users can take the advantage of multiple wireless networks. Some of the benefits and characteristics of wireless mesh networks are highlighted as follows: