Faouzi Derbel

Trends in smart metering

Especially in Europe there is a need to improve the end-use of energy in order to manage the demand of energy. This improvement leads to a contribution to the reduction of primary energy consumption as well as to the mitigation of CO2 and other greenhouse gas emissions. The EU Directive 2006/32/EC for the improvement of enduse of energy requires among others the introduction of smart metering systems.

An 863-870MHz spread-spectrum FSK transceiver design for wireless sensor

Simulation results of a 863-870-MHz frequency-hopped spread-spectrum transceiver with binary frequency shift keying (BFSK) modulation at 20 kb/s for wireless sensor applications is presented. The transmit/receive RF front end contains a BFSK modulator, an up conversion mixer, a power amplifier (PA), and an 863-870 MHz band pass filter (BPF) at the transmitter side and a low-noise amplifier with down conversion mixer to to zero IF, a low-pass channel-select filter, a limiter and a BFSK demodulator at the receiver side. The various blocks parameters of the transmit/receive RF front end like noise figure (NF), gain, 1 dB compression point (P-1dB)and IIP3 are simulated and optimized to meet transceiver specifications. The receiver simulations show 51.1 dB conversion gain, -7 dBm IIP3, -15 dB return loss (S11) and 10 dB NF. The transmitter simulations show an output ACPR (adjacent channel power ratio) of -22 dBc, 3.3 dBm P-1dB of PA and transmitted power of 0 dBm. The transceiver simulations show an RMS frequency error of 1.45 Khz.

A layered model for wireless sensor networks

Aiming at optimizing the use of a wireless sensor network (WSN) as a miniature components integrated on chip (according to SoC technology), the adoption of specific protocols in the fields of applications of such network type is crucial. WSNs differ largely from the traditional wireless networks, they consequently require the use of new variations of energy-preserving protocols to ensure a prolonged life span for a sensor and to allow autonomy for a mostly dynamic topology-characterized network. Indeed, several routing and medium access control (MAC) protocols were proposed, and often adapted to the targeted applicability (house automation, biology, security, rural…). In this paper, we put forward a layered model for WSNs, with reference to OSI, TCP/IP and IEEE802 models which guaranteed a simple design and an easy implementation, for computer networks on (LAN/Wi-LAN, WAN, PAN…), thanks to layer decomposition reducing complexity and outlining functionalities relating to layers/levels coordinating through specific interfaces. The suggested model defines the levels of abstraction features of a WSN nodes according to their types (sensor, base station “BS”…) and intelligence level so as to serve as a basic model for design and future implementations of WSNs protocols and applications. This layered model allows the interconnection of a WSN with any other type of computer network.

Smart metering based on automated meter reading

The new EU Directive 2006/32/EC for the improvement of end-use of energy requires among others the introduction of smart metering. Smart metering is basically performed with automated meter reading (AMR). This paper presents a wireless automated meter reading system Siemeca AMR. The system allows the wireless collecting as well as the reading out of the meter values installed in flats in distributed buildings without the intervention of persons. The meters are battery powered and reach a battery life time up to 12 years. The wireless transmission is standardized in according to the wireless M-Bus (EN 13757). This standard is compatible to Konnex-RF (EN50090) which is suitable for home automation. The AMR system leads to many advantages in relation to the metering process as well as to the possibility to offer added services. The paper deals in addition with factors influencing the wireless transmission approach. Mechanisms in physical.

Wireless sensor networks with power management for low energy consumption

Sensor nodes usually have very limited resources in terms of computing capacity, storage data, transmission and onboard energy. These limitations motivate a large part of the research issues in the field of wireless sensor networks, especially the energy constraint. However, energy consumption is a major systems-design challenge. By focusing on energy optimization, the wireless sensor networks could reinvigorate their strengths and loose the constraints that limit their development. Therefore, the wireless sensor networks require a global manager (network level) to manage the activities of the node and to maximize the lifetime of the battery while reducing the consumption of energy. This paper offers an overview of the routing protocols and of power management techniques and specifies the characteristics of the energy manager at global and local system. It can also express complex energy-related goals and behaviors, leading to more effective unified management policies.

Smart wireless Sub-Metering

This paper presents a new approach for using wireless sensor networks for Sub-Metering applications. Parameters regarding reliability and energy consumption have been investigated.

Energy-efficient model for indoor localization process based on wireless sensor networks

Although the research made in the field of indoor localization based on wireless sensor networks (WSN) has shown encouraging and sometimes adequate results in terms of position estimation accuracy, raising the network longevity is still a challenging issue especially when the used sensor nodes are battery-powered and their energy capacity is very limited. In this paper we present an energy efficient approach for indoor localization purpose that is based on optimizing the activity periods of the sensor nodes during the indoor localization process.

An 868 MHz sub-microsecond steady low-noise amplifier

A design of a cascaded low-noise amplifier (LNA) for radio receivers is presented. The single LNA stage emphasises a total power gain of 18 dB and depleting current of 600 μ A at 1.2 V. The input and output return losses are S11 = -12.28 dB and S22 = -20.62 dB respectively at 868 MHz with a corresponding noise figure of 1.5 dB. This LNA exhibits input-referred third-order intercept point of -28.6 dBm. For a possible operation of 1 μs the LnA is able to settle in less than 400 ns. The LNA is fabricated using discrete elements targeting Wake-Up receiver radios.

A real-time indoor localization platform based on wireless sensor networks

Instant knowledge of the current position of people and objects has become a concern for most of us. This can be a challenge when the sought object is located inside a building since the Global Positioning System (GPS) may not be helpful in this situation. For this reason many applications are revealed which use new technologies such as Wireless Sensor Networks (WSN). In this paper we present a prototype of an indoor localization platform that is able to provide a Real-Time estimation of target objects using as equipment the WSN and the lateration based on the computation of Received Signal Strength Indicator (RSSI) as a localization technique. With improvements in terms of signal processing we realize an accuracy of 1 m, which is very useful for many fields of applications.

Energy-efficient adaptive communication by preference-based routing and forecasting

Life simplifying fully automated factories are only feasible with a high accuracy and quality checking sensor density. In order to realize a huge amount of sensor nodes a single node must require minimal amount of energy for cost and uptime reasons. In this paper, a behavior adaptive routing protocol is presented which utilizes factory structures, resulting order relations, and application specific process data relevance to reduce energy requirements of nodes and increase their applicability. The reduction of data amount is realized by a parameter compressing data format and time-behavior adapted buffering. The reduction of number of transmissions is achieved by prevention of periodic updates and usage of echoes of other nodes. In order to react to dynamic environmental influences and energy fluctuations, sensor nodes improve their behavior. Change in behavior results from a compressed preference value. The accuracy of mapping of parameters to the preference is validated by several a priori rule checks and error adaptions.