Fernando J. Velez

Survey on the Characterization and Classification of Wireless Sensor Network Applications

Nowadays, wireless sensor network (WSN) users are demanding more and more in terms of choice and diversity of applications. Hence, as the diversity of applications is increasing, it is worthwhile to propose a structure for the set of characterization parameters that allows sketching a taxonomy for WSN applications. This taxonomy is established via an application-oriented approach, identifying the specific services offered by each application. In this survey, we fill this gap in the WSN literature by describing the characterization parameters, organized into six different categories. Our taxonomy for application classification is centered on the different sets of parameters that have high impact on a given future WSN application. Typical attributes and values from related research works are considered as a reference, but in this survey, we propose inter- and intra-connections among the considered application groups. Based on these connections, new application groups have been proposed for applications that share common characterization parameters, along with a holistic overview of WSN application taxonomy and the discussion of the three generations of WSNs toward communication between things and the Internet of Things, as well as future trends for the development of WSN applications. Moreover, detailed parameters from different projects and authors in the field of WSNs are joined together for comparison purposes.

Application of Wireless Sensor Networks to Automobiles

Application of Wireless Sensor Networks to Automobiles Some applications of Wireless Sensor Networks (WSNs) to the automobile are identified, and the use of Crossbow MICAz motes operating at 2.4 GHz is considered together with TinyOS support. These WSNs are conceived in order to measure, process and supply to the user diverse types of information during an automobile journey. Examples are acceleration and fuel consumption, identification of incorrect tire pressure, verification of illumination, and evaluation of the vital signals of the driver. A brief survey on WSNs concepts is presented, as well as the way the wireless sensor network itself was developed. Calibration curves were produced which allowed for obtaining luminous intensity and temperature values in the appropriate units. Aspects of the definition of the architecture and the choice/implementation of the protocols are identified. Security aspects are also addressed.

Cognitive radio for medical body area networks using ultra wideband

Wearable wireless medical sensors beneficially impact the healthcare sector, and this market is experiencing rapid growth. In the United States alone, the telecommunications services market for the healthcare sector is forecast to increase from

Spectrum Aggregation with Multi-band User Allocation over Two Frequency Bands

7.5 billion in 2008 to

Antennas and circuits for ambient RF energy harvesting in wireless body area networks

11.3 billion in 2013. Medical body area networks improve the mobility of patients and medical personnel during surgery, accelerate the patients¿ recovery, and facilitate the remote monitoring of patients suffering from chronic diseases. Currently, MBANs are being introduced in unlicensed frequency bands, where the risk of mutual interference with other electronic devices can be high. Techniques developed during the evolution of cognitive radio can potentially alleviate these problems in medical communication environments. In addition, these techniques can help increase the efficiency of spectrum usage to accommodate the rapidly growing demand for wireless MBAN solutions and enhance coexistence with other collocated wireless systems. This article proposes a viable architecture of an MBAN with practical CR features based on ultra wideband radio technology. UWB signals offer many advantages to MBANs, and some features of this technology can be exploited for effective implementation of CR. We discuss the physical and MAC layer aspects of the proposal in addition to the implementation challenges.

Smart-clothing wireless flex sensor belt network for foetal health monitoring

This paper seeks to explore the integration of spectrum and network resource management functionalities to the benefit of achieving higher performance and capacity gains in an IMT-A scenario. In particular, we investigate the allocation of users over two frequency bands (i.e., 2 GHz and 5 GHz ones) for a single operator scenario. The same type of RAT is considered for both frequency bands. It is assumed that the operator considered in this work has gained access to the frequency pool with a certain portion of the available spectrum. The operator has access to a non-shared 2 GHz band and to part (or all) of the frequency pool band at 5 GHz. The performance gain is analyzed in terms of higher data throughput, reduced delay and lower blocking probability. The performance is heavily dependent on the channel quality for each user in the considered bands which, in turn, is a function of the path loss and the distance from the base station (BS). The operator will have relevant improvements when user terminals are heterogeneously distributed on the cell, with variable distances from the BS. A gain up to 400 kbps (22%) was obtained with the proposed suboptimal solution.

QoS Metrics for Cross-Layer Design and Network Planning for B3G Systems

In this paper, we identify the spectrum opportunities for radio frequency (RF) energy harvesting through power density measurements from 350 MHz to 3 GHz. The field trials have been performed in Covilhâ by using the NAKDA-SMR spectrum analyser with a measuring antenna. Based on the identification of the most promising opportunities, a dual-band band printed antenna operating at GSM bands (900/1800) is proposed, with gains of the order 1.8-2.06 dBi and efficiency 77.6-84%. Guidelines for the design of RF energy harvesting circuits and choice of textile materials for a wearable antenna are also discussed. Besides, we address the guidelines for designing circuits to harvest energy in a scenario where a wireless body area network (WBAN) is being sustained by a TX91501 Powercasf® RF dedicated transmitter and a five-stage Dickson voltage multiplier responsible for harvesting the RF energy. The IRIS motes, considered for our WBAN scenario, can perpetually operate if the RF received power attains at least -10 dBm.

Carbon Fiber Epoxy Composites for Both Strengthening and Health Monitoring of Structures

In the past years low power circuits design and networking techniques not only reduce the total power, requirements for Wireless Sensor Networks (WSNs) but also allow for supporting more complexity. In this paper we present solutions for WSN applications, and design aspects in the context of patient monitoring. The solution presented whose primary function is to collect the vital data remotely from the various sensors in low-rate wireless personal area network (LR-WPAN) is based on the IEEE 802.15.4 standard. It also will includes a Wi-Fi Layer in the context of hybrid networks. The application being dealt here consist of several flex sensors attached to a wearable monitoring belt, and allows for monitoring the foetal movements for a pregnant woman.

Aspects of cellular planning for emergency and safety services in mobile WiMax networks

After 3G mobile and wireless systems take-up, the research community is now directing its interest towards unified ways of looking at system design, optimization, and quality of service (QoS) issues to satisfy the requirements of next generation multi-service mobile and wireless IP-based networks. Their implementation requires the development of IP QoS architecture and mechanisms encompassing the various layer of the OSI Model to cope with the new requirements. This work identifies the requirements on latency (link radio), latency (end-to-end), bit error rate, data rates, and traffic characterisation for mobile multimedia network beyond 3G. Characterisation parameters were identified and values were suggested for their range of variation, in the context of cross-layer design.

Overview of progress in Smart-Clothing project for health monitoring and sport applications

This paper presents a study of the electrical and mechanical behavior of several continuous carbon fibers epoxy composites for both strengthening and monitoring of structures. In these composites, the arrangement of fibers was deliberately diversified to test and understand the ability of the composites for self-sensing low strains. Composites with different arrangements of fibers and textile weaves, mainly unidirectional continuous carbon reinforced composites, were tested at the dynamometer. A two-probe method was considered to measure the relative electrical resistance of these composites during loading. The measured relative electrical resistance includes volume and contact electrical resistances. For all tested specimens, it increases with an increase in tensile strain, at low strain values. This is explained by the improved alignment of fibers and resulting reduction of the number of possible contacts between fibers during loading, increasing as a consequence the contact electrical resistance of the composite. Laboratory tests on strengthening of structural elements were also performed, making hand-made composites by the “wet process”, which is commonly used in civil engineering for the strengthening of all types of structures in-situ. Results show that the woven epoxy composite, used for strengthening of concrete elements is also able to sense low deformations, below 1%. Moreover, results clearly show that this textile sensor also improves the mechanical work of the strengthened structural elements, increasing their bearing capacity. Finally, the set of obtained results supports the concept of a textile fabric capable of both structural upgrade and self-monitoring of structures, especially large structures of difficult access and needing constant, sometimes very expensive, health monitoring.