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.

http://www.alansonsample.com/publications/docs/2008%20-%20TIM%20-%20Design%20RFID%20Based%20Battery%20Free%20Programmable%20Sensing%20Platform.pdf

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

The aim of the present paper is to review the technical and scientific state of the art of wireless sensor technologies and standards for wireless communications in the Agri-Food sector. These technologies are very promising in several fields such as environmental monitoring, precision agriculture, cold chain control or traceability. The paper focuses on WSN (Wireless Sensor Networks) and RFID (Radio Frequency Identification), presenting the different systems available, recent developments and examples of applications, including ZigBee based WSN and passive, semi-passive and active RFID. Future trends of wireless communications in agriculture and food industry are also discussed.

/pdf/a-review-of-wireless-sensor-technologies-and-applications-in-3sanx79t5n.pdf

A Review of Wireless Sensor Technologies and Applications in Agriculture and Food Industry: State of the Art and Current Trends

The growing complexity of customizable single-chip multiprocessors is requiring communication resources that can only be provided by a highly-scalable communication infrastructure. This trend is exemplified by the growing number of network-on-chip (NoC) architectures that have been proposed recently for system-on-chip (SoC) integration. Developing NoC-based systems tailored to a particular application domain is crucial for achieving high-performance, energy-efficient customized solutions. The effectiveness of this approach largely depends on the availability of an ad hoc design methodology that, starting from a high-level application specification, derives an optimized NoC configuration with respect to different design objectives and instantiates the selected application specific on-chip micronetwork. Automatic execution of these design steps is highly desirable to increase SoC design productivity. This work illustrates a complete synthesis flow, called Netchip, for customized NoC architectures, that partitions the development work into major steps (topology mapping, selection, and generation) and provides proper tools for their automatic execution (SUNMAP, xpipescompiler). The entire flow leverages the flexibility of a fully reusable and scalable network components library called xpipes, consisting of highly-parameterizable network building blocks (network interface, switches, switch-to-switch links) that are design-time tunable and composable to achieve arbitrary topologies and customized domain-specific NoC architectures. Several experimental case studies are presented In the work, showing the powerful design space exploration capabilities of the proposed methodology and tools.

/pdf/noc-synthesis-flow-for-customized-domain-specific-349xz2ar6f.pdf

NoC synthesis flow for customized domain specific multiprocessor systems-on-chip

Current wireless technologies, such as wireless body area networks and wireless personal area networks, provide promising applications in medical monitoring systems to measure specified physiological data and also provide location-based information, if required. With the increasing sophistication of wearable and implantable medical devices and their integration with wireless sensors, an ever-expanding range of therapeutic and diagnostic applications is being pursued by research and commercial organizations. This paper aims to provide a comprehensive review of recent developments in wireless sensor technology for monitoring behaviour related to human physiological responses. It presents background information on the use of wireless technology and sensors to develop a wireless physiological measurement system. A generic miniature platform and other available technologies for wireless sensors have been studied in terms of hardware and software structural requirements for a low-cost, low-power, non-invasive and unobtrusive system.

https://iopscience.iop.org/article/10.1088/0967-3334/29/11/R01/pdf

Wireless body sensor networks for health-monitoring applications.

The human body characteristics as a signal transmission medium are studied for the application to intrabody communication. The measurements of the body channel cover the frequency range from 100 kHz to 150 MHz and the distance on the body up to 1.2 m. A distributed RC model is developed to analyze the large variation of the channel properties according to the frequency and channel length. The simulation results using the channel model match well with the measurements in both the frequency and time domains. The effect of the ground plane to the body channel transceivers is also investigated and an empirical formula for the minimum ground size is obtained. Finally, the amount of the electromagnetic radiation due to the body antenna effect is measured. With regards to the Federal Communications Commission regulations, the proper frequency range for the intrabody communication is determined to satisfy given bit error rate requirements

/pdf/the-human-body-characteristics-as-a-signal-transmission-2vgjz7wops.pdf

The Human Body Characteristics as a Signal Transmission Medium for Intrabody Communication

An RF-powered transponder with temperature and photo sensors is designed and fabricated for environmental monitoring. The transponder gathers power from external ISM (860-960MHz) band RF signal and senses ambient temperature and light. It contains a supply voltage generator, a temperature-compensated ring oscillator, an oversampling synchronizer, a PTAT temperature sensor and an abrupt transition buffered photo sensor. Its internal clock frequency has variation less than 7% for 1.5-V supply voltage and 90/spl deg/C temperature change. The transponder occupies 0.4mm/sup 2/ with 0.25-/spl mu/m CMOS process and dissipates only 5.14-/spl mu/W during active state.

/pdf/a-5-1-spl-mu-w-uhf-rfid-tag-chip-integrated-with-sensors-for-54cg4lvrc7.pdf

A 5.1-/spl mu/W UHF RFID tag chip integrated with sensors for wireless environmental monitoring

This paper presents a low-power wideband signaling (WBS) digital transceiver for data transmission through a human body for body area network applications. The low-power and highspeed human body communication (HBC) utilizes a digital transceiver chip based on WBS and adopts a direct-coupled interface (DCI) which uses an electrode of 50-Omega impedance. The channel investigation with the DCI identities an optimum channel bandwidth of 10 kHz to 100 MHz. The WBS digital transceiver exploits a direct digital transmitter and an all-digital clock and data recovery (CDR) circuit. To further reduce power consumption, the proposed CDR circuit incorporates a low-voltage digitally-controlled oscillator and a quadratic sampling technique. The WBS digital transceiver chip with a 0.25-mum standard CMOS technology has 2-Mb/s data rate at a bit error rate of 1.1 times 10-7, dissipating only 0.2 mW from a 1-V supply generated by a 1.5-V battery.

A 0.2-mW 2-Mb/s Digital Transceiver Based on Wideband Signaling for Human Body Communications

A 108/spl times/60mm/sup 2/ prototype chip is implemented with a star-connected on-chip network The chip consists of a PLL, 1KB SRAM, two 2/spl times/2 crossbar switches, Up/Down-Samplers, two off-chip gateways, and synchronizers The on-chip network contains 81k transistors, dissipates 264mW at 23V and 800MHz, and provides 16GB/s per port and 128GB/s aggregated bandwidth, supporting plesiochronous communication without global synchronization

/pdf/an-800mhz-star-connected-on-chip-network-for-application-to-4tmqtn0ycc.pdf

An 800MHz star-connected on-chip network for application to systems on a chip

A regulated charge pump circuit is realized in a 3.3-V 0.13-/spl mu/m CMOS technology. The charge pump exploits an automatic pumping control scheme to provide small ripple output voltage and fast start-up by decoupling output ripple and start-up time. The automatic pumping control scheme is composed of two schemes, an automatic pumping current control scheme and an automatic pumping frequency control scheme. The former automatically adjusts the size of pumping driver to reduce ripple voltage according to output voltage. The latter changes the pumping period by controlling a voltage-controlled oscillator (VCO). The output frequency of the VCO varies from 400 kHz to 600 kHz by controlling the input bias voltage of the VCO. The prototype chip delivers regulated 4.5-V output voltage from a supply voltage of 3.3 V with a flying capacitor of 330 nF, while providing 30 mA of load current. The area is 0.25 mm/sup 2/ and the measured output ripple voltage is less than 33.8 mV with a 2-/spl mu/F load capacitor. The power efficiency is greater than 70% at the range of load current from 1 to 30 mA. An analytical model for ripple voltage and recovery time is proposed demonstrating a reasonable agreement with SPICE simulation results.

/pdf/a-regulated-charge-pump-with-small-ripple-voltage-and-fast-24u7s19jz4.pdf

Seong-Jun Song

Papers

The Human Body Characteristics as a Signal Transmission Medium for Intrabody Communication

A 5.1-/spl mu/W UHF RFID tag chip integrated with sensors for wireless environmental monitoring

A 0.2-mW 2-Mb/s Digital Transceiver Based on Wideband Signaling for Human Body Communications

An 800MHz star-connected on-chip network for application to systems on a chip

A regulated charge pump with small ripple voltage and fast start-up