Wireless Identification And Sensing Platform Research Articles

Design and Implementation of Wireless Identification and Sensing Platform in Structure Monitoring

In the process of structure monitoring, active wireless sensor devices are often used. In order to replace the energy limitation bottleneck of the power supply unit, the Wireless Identification and Sensing Platform (WISP) with real-time data transmission function is adopted to realize the collection of structural vibration acceleration data. Firstly, the various functional modules of the WISP with three-axis acceleration are introduced. Then, through software programming of the low-power MSPF430F2132 microprocessor on it, the drive and control of the external three-axis acceleration sensor ADXL330 is realized. Finally, it was tested through comparative experiments. The research results show that the acceleration data monitored by the WISP is accurate, effective and reliable. Compared with the active wireless Narada unit, the similarity is more than 83%. Compared with the OpenSEES system, the accuracy of the structure frequency monitored by the WISP is 99.07%. Therefore, it is feasible and reliable to use the WISPs to perform multi-point deployment control in structural dynamic monitoring.

XORSHIFTUL+: A Novel Hybrid Random Number Generator for Internet Of Things And Wireless Sensor Network Applications

There are an increasing number of lightweight devices such as smart cards, radio frequency identification (RFID) tags, wireless sensor nodes and devices associated with the Internet of Things (IoT) concept, all of which need effective and lightweight security structures. One of the basic elements used in authentication protocols is the nonce values that are generated by PRNGs. Also random numbers are used for encryption process in secure communication. Proposed PRNG has demonstrated great suitability for devices with limited resources in terms of performance, resource usage and randomness. This generator is tested with NIST statistical test suite (NIST STS), which is one of the most comprehensive randomness test tools. It is also implemented, tested on wireless identification and sensing platform (WISP) passive RFID tag and compared with well-known PRNGs. As a result of the comparisons, it has better results than its rivals.

On the Synchronization of Computational RFIDs

Battery-free computational RFID platforms, such as WISP (Wireless Identification and Sensing Platform), are intermittently-powered devices designed for replacing existing sensor networks. Accordingly, synchronization appears as one of the crucial building blocks for collaborative and coordinated actions in these platforms. However, intermittent power leads to frequent loss of computational state and short-term clock frequency instability that makes synchronization challenging. In this article, we introduce the WISP-Sync protocol that provides synchronization among WISP tags in the communication range of an RFID reader. WISP-Sync overcomes the aforementioned challenges by employing a Proportional-Integral (PI) controller-inspired algorithm which (i) is adaptive—reactive to short-term clock instabilities; (ii) requires only a few computation steps—suitable for limited harvested energy; and (iii) keeps a few variables to hold the synchronization state—minimum overhead to recover from power interrupts. Evaluations in our testbed showed that WISP-Sync ensured an average synchronization error of approximately 1 ms among the tags with an average energy overhead of 1.85 $\mu$μJ per synchronization round.

Cloud access control authentication system using dynamic accelerometers data

SummaryThe main challenge of access control system is how to allow authorized users to access quickly and accurately. In reality, most access control system cannot run smoothly with the adverse impact of a security problem, it is because the access control card is easy to duplicate. To improve system security, recent efforts introduced biological technologies, such as fingerprint identification, facial recognition, and iris recognition. However, these methods are costly for installation and later maintenance. In this paper, we introduce a cloud access control system that employs the ability of sensing acceleration of Wireless Identification and Sensing Platform (WISP) tags combined with customized motions. Users are allowed to pass the access control system only if they operate user‐defined motions correctly. Authorized users can define the authentication motions by themselves, which not only facilitates the daily use but also improves the security of the cloud access control system. We conduct intensive experimental measurements. The experimental results verify the effectiveness of our proposed system.

Adaptive scheduling to enhance data security and energy efficiency on energy harvesting platform

Radio-frequency (RF)-based energy harvesting platforms are appealing for always-on applications due to its radio frequency energy harvesting capability. However, the current RF-based energy harvesting capability is limited by many factors including harvesting distance, device constraints, communication, and security. RF-based energy harvesting platforms tend to harvest less energy as the device is further away, and impacts the ability to execute its own applications properly. The limited storage of energy on such platforms will make it even challenging to implement energy-hungry security functions on top of basic functions such as sensing, computing and transmitting. Therefore, by default, a lot of RF-based energy harvesting platforms have no basic security functions implemented, which is not acceptable for security-sensitive applications such as biomedical applications.In this paper, we propose an adaptive light-weight scheduling mechanism that aims to balance data security and energy efficiency for application on RF-based energy-harvesting platforms. We will then prototype this scheduler on a Wireless Identification and Sensing Platform (WISP) device. The results in this paper will test this scheduling mechanism in action on a WISP device, along with use of a sensor to determine energy impact on the device, a deadline-based mechanism for data distribution, and finally comparing these cases with average voltage and total time.

A Preliminary Design Of Application Of Wireless Identification And Sensing Platform On External Beam Radiotherapy

A linear accelerator (linac) is widely used as a means of radiotherapy by focusing high-energy photons in the targeted tumor of patient. Incorrectness of the shooting can lead normal tissue surrounding the tumor received unnecessary radiation and become damaged cells. A method is required to minimize the incorrectness that mostly caused by movement of the patient during radiotherapy process. In this paper, the Wireless Identification and Sensing Platform (WISP) architecture was employed to monitor in real time the movement of the patient’s body during radiotherapy process. In general, the WISP is a wearable sensors device that can transmit measurement data wirelessly. In this design, the measurement devices consist of an accelerometer, a barometer and an ionizing radiation sensor. If any changes in the body position which resulted in incorrectness of the shooting, the accelerometer and the barometer will trigger a warning to the linac operator. In addition, the radiation sensor in the WISP will detect unwanted radiation and that can endanger the patient. A wireless feature in this device can ease in implementation. Initial analyses have been performed and showed that the WISP is feasible to be applied on external beam radiotherapy.

Towards balanced energy charging and transmission collision in wireless rechargeable sensor networks

By integrating sensing and computing capabilities into the traditional radio frequency identification (RFID) tags, the wireless identification and sensing platform (WISP) opens up a new research area referred to as wireless rechargeable sensor networks (WRSNs). Since WISPs need to be fully charged and then can start communication with the reader, thus the energy charging and transmission collision of WISPs are different from those of RFID tags. If the reader power is large, WISPs will be charged fast and start data transmission almost at the same time, which results in heavy transmission collision and the communication delay would be extremely large. However, if the reader power is small, WISPs will be charged slow and start data transmission one by one even without collisionh between any two WISPs, but the charging period of the whole network would be extremely large. Therefore, this paper aims at determining an optimal reader power towards balanced energy charging and transmission collision, such that the total duration for all WISPs to be fully charged and completely communicated is minimized. Firstly, we investigate on dynamic reader power with transmission collision avoidance, and static reader power towards balanced energy charging and transmission collision. Then, we derive the optimal reader power in three cases: (i) One reader and ray-uniformly distributed WISPs; (ii) one reader and randomly distributed WISPs; and (iii) multiple readers and randomly distributed WISPs. Finally, the theoretical analysis is verified through extensive evaluations.

Optimal Charging in Wireless Rechargeable Sensor Networks

Recent years have witnessed several new promising technologies to power wireless sensor networks, which motivate some key topics to be revisited. By integrating sensing and computation capabilities to the traditional radio-frequency identification (RFID) tags, the Wireless Identification and Sensing Platform (WISP) is an open-source platform acting as a pioneering experimental platform of wireless rechargeable sensor networks. Different from traditional tags, an RFID-based wireless rechargeable sensor node needs to charge its onboard energy storage above a threshold to power its sensing, computation, and communication components. Consequently, such charging delay imposes a unique design challenge for deploying wireless rechargeable sensor networks. In this paper, we tackle this problem by planning the optimal movement strategy of the mobile RFID reader, such that the time to charge all nodes in the network above their energy threshold is minimized. We first propose an optimal solution using the linear programming (LP) method. To further reduce the computational complexity, we then introduce a heuristic solution with a provable approximation ratio of (1 + θ)/(1 - ε) by discretizing the charging power on a 2-D space. Through extensive evaluations, we demonstrate that our design outperforms the set-cover-based design by an average of 24.7%, whereas the computational complexity is O((N/ε) <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> ). Finally, we consider two practical issues in system implementation and provide guidelines for parameter setting.

Tag-based cooperative data gathering and energy recharging in wide area RFID sensor networks

The Wireless Identification and Sensing Platform (WISP) conjugates the identification potential of the RFID technology and the sensing and computing capability of the wireless sensors. Practical issues, such as the need of periodically recharging WISPs, challenge the effective deployment of large-scale RFID sensor networks (RSNs) consisting of RFID readers and WISP nodes. In this view, the paper proposes cooperative solutions to energize the WISP devices in a wide-area sensing network while reducing the data collection delay. The main novelty is the fact that both data transmissions and energy transfer are based on the RFID technology only: RFID mobile readers gather data from the WISP devices, wirelessly recharge them, and mutually cooperate to reduce the data delivery delay to the sink. Communication between mobile readers relies on two proposed solutions: a tag-based relay scheme, where RFID tags are exploited to temporarily store sensed data at pre-determined contact points between the readers; and a tag-based data channel scheme, where the WISPs are used as a virtual communication channel for real time data transfer between the readers. Both solutions require: (i) clustering the WISP nodes; (ii) dimensioning the number of required RFID mobile readers; (iii) planning the tour of the readers under the energy and time constraints of the nodes. A simulative analysis demonstrates the effectiveness of the proposed solutions when compared to non-cooperative approaches. Differently from classic schemes in the literature, the solutions proposed in this paper better cope with scalability issues, which is of utmost importance for wide area networks.

Achieving Collision-Free Communication by Time of Charge in WRSN

The Wireless Identification and Sensing Platform (WISP) Sample et al. (IEEE T Instrum Meas 57(11):2608---2615, 2008) has become a very promising experimental platform of wireless rechargeable sensor networks (WRSN), which integrates the sensing and computation capabilities to the traditional RFID tags. In such kind of networks, the simultaneous transmission may introduce severe communication collisions, which have attracted various research efforts for resolving such collisions at the MAC layer. However, different from existing works, we avoid such communication collisions through proper reader movement by exploiting the differences in the time of charge among rechargeable sensor nodes. We formulate the optimization problem and prove that complexity of the optimal solution is NP-hard, and propose a simple yet effective algorithm to optimize both the reader stop location and stop time for minimizing the total communication delay. Extensive simulations under different system settings show that our design can largely reduce the communication delay and outperform the baseline design by at least 20 %.

Energy Provisioning in Wireless Rechargeable Sensor Networks

Wireless rechargeable sensor networks (WRSNs) have emerged as an alternative to solving the challenges of size and operation time posed by traditional battery-powered systems. In this paper, we study a WRSN built from the industrial wireless identification and sensing platform (WISP) and commercial off-the-shelf RFID readers. The paper-thin WISP tags serve as sensors and can harvest energy from RF signals transmitted by the readers. This kind of WRSNs is highly desirable for indoor sensing and activity recognition and is gaining attention in the research community. One fundamental question in WRSN design is how to deploy readers in a network to ensure that the WISP tags can harvest sufficient energy for continuous operation. We refer to this issue as the energy provisioning problem. Based on a practical wireless recharge model supported by experimental data, we investigate two forms of the problem: point provisioning and path provisioning. Point provisioning uses the least number of readers to ensure that a static tag placed in any position of the network will receive a sufficient recharge rate for sustained operation. Path provisioning exploits the potential mobility of tags (e.g., those carried by human users) to further reduce the number of readers necessary: mobile tags can harvest excess energy in power-rich regions and store it for later use in power-deficient regions. Our analysis shows that our deployment methods, by exploiting the physical characteristics of wireless recharging, can greatly reduce the number of readers compared with those assuming traditional coverage models.

On measuring the parasitic backscatter of sensor-enabled UHF RFID tags

Radio-frequency identification (RFID) tags have found their way into many applications. When tags implement cryptographic algorithms, side-channel analysis (SCA) attacks become a concern. Especially tags in the ultra-high frequency (UHF) range are susceptible to so-called parasitic-backscatter attacks that can be applied from a distance. Whereas it is known that such attacks are a threat for passive low-cost tags, no results are so far available for sensor-enabled tags. In this work, we evaluate the parasitic backscatter of wireless identification and sensing platform (WISP) tags by conducting differential electromagnetic analysis (DEMA) attacks. We apply the attacks on a passively as well as a semi-passively operated WISP tag from a distance of 30 cm and compare the results with an attack on a commercial low-cost tag. The results show that the evaluated WISP tags are less susceptible to DEMA attacks based on the parasitic backscatter than the evaluated commercial low-cost tag. Moreover, we present a measurement approach that allows to detect the weak parasitic backscatter modulated on the strong reader field without the need for an expensive hardware receiver or a dedicated demodulation circuit.

Data remanence effects on memory-based entropy collection for RFID systems

Random number generation is a fundamental security primitive. This relatively simple requirement is beyond the capacity of passive RFID (radio frequency identification) tags, however. A recent proposal, fingerprint extraction and random number generation in SRAM (FERNS), uses onboard RAM as a randomness source. Unfortunately, practical considerations prevent this approach from reaching its full potential. First, the amount of RAM available for utilization as a randomness generator may be severely restricted due to competition with other system functionalities. Second, RAM is subject to data remanence; there is a period after losing power during which stored data remains intact in memory. Thus, after memory has been used for entropy collection once it will require time without power before it can be reused. This may lead to unacceptable delays in a usable security application. In this paper, the practical considerations that must be taken into account when using RAM as an entropy source are demonstrated. The implementation of a true random number generator on Intel’s WISP (wireless identification and sensing platform) RFID tag is also presented, which is the first to the authors’ best knowledge. By relating this to the requirements of some popular RFID authentication protocols, the practicality of utilizing memory-based randomness techniques on resource-constrained devices is assessed.

Wireless strain measurement for structural testing and health monitoring of carbon fiber composites

A novel device patented by Intel and called WISP (Wireless Identification and Sensing Platform) is modified to interface with a conventional foil resistance strain gage. The wireless, battery-free, digital device communicates with and is powered by an Ultra-High Frequency (UHF) RFID (Radio Frequency Identification) reader. The standard Intel WISP has been modified with the addition of a PCB (printed circuit board), which act as the analog interface with the strain gage. The so-called WISPs/g (for strain gage) has been utilized during uniaxial tension tests on carbon fiber composite specimens to compare accuracy and repeatability with conventional wired strain gage and extensometer. Validation of the technology is performed with a structural test, whereby four independent WISPs/g devices are positioned on the surface of a carbon fiber composite flat panel subjected to quasi-static indentation. Measurements are compared to the predictions of a NASTRAN finite element model (FEM) and show excellent agreement. Applications of this technology include strain measurement during static airframe tests, as well as on-board real-time strain measurements during test flight and certification of new aircraft.

Design of an RFID-Based Battery-Free Programmable Sensing Platform

This paper presents the wireless identification and sensing platform (WISP), which is a programmable battery-free sensing and computational platform designed to explore sensor-enhanced radio frequency identification (RFID) applications. WISP uses a 16-bit ultralow-power microcontroller to perform sensing and computation while exclusively operating from harvested RF energy. Sensors that have successfully been integrated into the WISP platform to date include temperature, ambient light, rectified voltage, and orientation. The microcontroller encodes measurements into an electronic product code (EPC) Class 1 Generation 1 compliant ID and dynamically computes the required 16-bit cyclical redundancy checking (CRC). Finally, WISP emulates the EPC protocol to communicate the ID to the RFID reader. To the authors' knowledge, WISP is the first fully programmable computing platform that can operate using power transmitted from a long-range (UHF) RFID reader and communicate arbitrary multibit data in a single response packet.

Battery-free Wireless Identification and Sensing

The Wireless Identification and Sensing Platform (WISP) project explores an approach to provide power for sensor networks, based on passive radio-frequency-identification technology. In traditional passive RFID systems, ambient high-power readers interrogate battery-free devices, called tags, that modulate the interrogating signal to communicate a unique identifier to the reader. The WISP project aims to augment RFID tags with sensors so that tags can also send sensed data to the readers. We call these augmented tags wisps. Basing wisps on RFID has some immediate advantages. RFID tags communicate to ambient readers over distances of up to eight meters. Solutions compatible with RFID standards might therefore find quicker acceptance and see faster improvement than other solutions.