Cristiano Scavongelli

Performance analysis of JPEG 2000 over 802.15.4 wireless image sensor network

This paper presents a performance analysis of JPEG 2000 image compression over a 802.15.4 wireless network. The interdependence among image quality, JPEG 2000 compression parameters and network throughput have been investigated. The objective of the work is to give useful guidelines in the design of image wireless networks over low cost, low power, low rate 802.15.4 wireless protocol.

Battery Management System (BMS) simulation environment for electric vehicles

The wide diffusion of Full and Hybrid Electric Vehicles is stimulating research on electric energy storage systems and Battery Management Systems (BMS). The Battery management system must ensure many complex features such as charge control, battery-capacity monitoring, remaining run-time information and charge-cycle counting. An optimization of the BMS can allow an improvement on security of the vehicle, performance of the engine, energy optimization and extension of the life of the battery. The main objective of this work is to develop a simulation environment based on SystemC to design and optimize the Battery Management System including a lithium-ion battery model and CAN communication interface. The BMS has been validated using real-world scenarios and data.

Active role of a NFC enabled smartphone in EV-EVSE charging process

Management of charge of electrical vehicles (EV) can be effectively integrated in a Vehicle To Grid (V2G) system. This regulated operation is described in the ISO/IEC 15118 standard. We propose a modification of the original protocol: in our scheme the smartphone has an active role in the EV - EVSE communication, being able to integrate itself in the EV charge. We developed an application for Android smartphone affords to the customer to completely control the process of charge in all its phases: authentication to the service, choice of the charge parameters, monitoring of the charge and payment. To obtain that, a modification to standard ISO/IEC 15118 is proposed. Actually, only the communication between vehicle (EV) and station (EVSE) is permitted. In our proposed model, the communication between vehicle, station and smartphone is realized in wireless mode through the Bluetooth protocol, introducing the active role of the smartphone. The App use NFC (Near Field Communication) technology, in order to simplify and to accelerate the Bluetooth login operation, V2G service authentication and related payment. Two specific PC-Windows software are developed, simulating the behaviors of the electrical vehicle (EV) and of the charge station (EVSE) according the standard. Moreover, a reusable NFC library has been developed to permit immediate authentication and two-ways transmission session, using Bluetooth and NFC in p2p mode.

Effects of variability of the characteristics of single cell on the performance of a lithium-ion battery pack

Rising crude oil prices and worldwide awareness of environmental issues have resulted in increased research and development of energy storage systems. Batteries are one of the most attractive energy storage systems because of their high efficiency and low pollution. Because of their high-energy densities and long lifetimes, lithium-ion batteries are increasingly used not only in electrical vehicles, but also in other applications. A key point in the management of lithium-ion batteries is expanding their energy storage capability and lifetimes. To achieve this, a fundamental embedded system is the battery management system (BMS) needed to ensure optimal, reliable and safe operation of the battery. Modelling and characterization of the single cells and an efficient simulation environment is fundamental for the development of an efficient BMS. This work presents a study of the statistical variations of the characteristic parameters of the single cells on the performances of a battery pack. The Montecarlo method on the SystemC-WMS simulations has been used.

FPGA implementation of JPEG encoder architectures for wireless networks

Due to its relative simplicity, the JPEG compression algorithm requires less hardware or software resources with respect to new compression algorithms, for example the JPEG2000 and the JPEG XR. This makes it suitable for low-power applications. Moreover, features embedded in the JPEG2000 and the JPEG XR, such as the scalability of the image stream, can be added to the main JPEG core, making an encoder useful for example in a video surveillance wireless network. Nevertheless, actual JPEG dedicated hardware realizations do not implement many features of the compression standard. In this work, we developed several JPEG encoder architectures with full real-time reconfigurability and support for the restart intervals and, for a simple scalability mechanism, the scan scheme. These features make the architectures suitable for the use in low-bandwidth, low-power wireless networks. The JPEG encoder architectures have been developed starting from a SystemC model and then implemented in a FPGA.

Fall Detection Using Wearable Accelerometers and Smartphone

The governments are investing in research on solutions for independent living, active ageing, at home health monitoring, with the objective of a significant prolongation of personal autonomy of older people. Fall avoidance and fall detection are important aspects of health care of ageing people. The proposed fall detection system consists in a wireless network with a smartphone and a board with another 3-axis accelerometer. The algorithm for fall detection is a part of a user friendly application developed for the smartphone. A comparison with existing fall detection systems and algorithms is reported.

Piezoelectric Energy Harvesting on Running Shoes

One of the strong requirements of wireless sensor networks is the low power consumption in order to extend the life of the network itself. This constraint is even stronger for body area networks. Energy harvesting is an interesting solution that captures the energy from the environment. This work presents an electromechanical model of a piezoelectric transducer in a cantilever configuration. The model has been used to design and optimize an energy harvesting system, that has been placed on a running shoe, that can be used to feed energy for sensors of body area networks.

Energy estimation in SystemC with Powersim

Abstract This paper presents a methodology to estimate the dissipation of energy in hardware, at any level of abstraction, with Powersim. Powersim is a C++ class library aimed to the calculation of energy dissipation of hardware described in SystemC. To this end C++ operators are monitored and a different energy model is used for each data type. Energy models are functions of operator inputs, constant parameters and variables, like supply voltage. The main advantage of this approach is that energy estimation does not require any change in the source code describing the hardware. As application examples, the computational complexity of a JPEG encoder, implemented in a FPGA, and a FIR filter, implemented in a microcontroller, are presented.

A SystemC Bluetooth network simulator

As the wireless networks utilization grows up and the technology becomes more powerful, the complexity of the possible applications increases. With the current hardware potentiality, its unavoidable to make use of simulation tools to develop, improve and optimize the designed networks. Many network simulators are available, but they mainly concentrate on the protocol aspects of the design, i.e. they work on a very high level of abstraction. Rather, in many applications it may be useful, important or even critical to observe and manage at the same time high-level and low-level parameters like the power in the channel, the packet loss, or more specific network configuration details. In this paper we present a Bluetooth network simulator that let the user to work both on application level and on link management level. The Bluetooth simulator has been implemented using SystemC and it has been developed with the aim of modeling a real microcontroller-based device.

Cloud-based system for waste electrical and electronic equipment

The growing market of electronic appliances is nowadays introducing a new kind of problem: the disposal management of a great quantity of broken or simply outdated electric and electronic devices. Sometimes the equipment contain dangerous or precious materials, that must be handled carefully. Furthermore, several good and valuable components on broken equipment could be reused. In this work, we present a Web based system conceived and designed to maintain all those information that can improve the end-of-life management of an electronic appliance. The cloud database can be easily accessed using the RFId technology, allowing the traceability of the equipment and the single components in the manufacturing, use, reuse and end-of-life phases.