Baseband-processor for a passive UHF RFID transponder

This paper describes the design of a digital processor targeting the Class-1 Generation-2 EPC Protocol for UHF RFID transponders, and proposes different techniques for reducing its power consumption. The processor has been implemented in a 0.35μm CMOS technology process using automatic tools for both the logic synthesis and layout. Post-layout simulations confirm the fully functionality of the prototype and predict a worst-case power consumption of only 2.9μA at 1.2V supply.Ministerio de Educación y Ciencia TEC2006-03022, TEC2009-08447Junta de Andalucía TIC-0281

A low power signal front-end for passive UHF RFID transponders with a new clock recovery circuit.

Chan, Chi Fat.Thesis (M.Phil.)--Chinese University of Hong Kong, 2009.Includes bibliographical references.Abstracts in English and Chinese.Abstract --- p.2摘要 --- p.5Acknowledgement --- p.7Table of Contents --- p.9List of Figures --- p.11List of Tables --- p.14Chapter 1. --- Introduction --- p.15Chapter 1.2. --- Research Objectives --- p.16Chapter 1.3. --- Thesis Organization --- p.18Chapter 1.4. --- References --- p.19Chapter 2. --- Overview of Passive UHF RFID Transponders --- p.20Chapter 2.1. --- Types of RFID Transponders and Design Challenges of Passive RFID Transponder --- p.20Chapter 2.2. --- Selection of Carrier Frequency --- p.22Chapter 2.3. --- Description of Transponder Construction --- p.22Chapter 2.3.1. --- Power-Generating Circuits --- p.23Chapter 2.3.2. --- Base Band Processor --- p.28Chapter 2.3.3. --- Signal Front-End --- p.29Chapter 2.4. --- Summary --- p.30Chapter 2.5. --- References --- p.31Chapter 3. --- ASK Demodulator for EPC C-l G-2 Transponder --- p.32Chapter 3.1. --- ASK Demodulator Design Considerations --- p.32Chapter 3.1.1. --- Recovered Envelope Distortion --- p.32Chapter 3.1.2. --- Input Power Level Considerations --- p.34Chapter 3.1.3. --- Input RF power Intercepted by ASK Demodulator --- p.36Chapter 3.2. --- ASK Demodulator Design From [3-4] --- p.36Chapter 3.2.1. --- Envelope Waveform Recovery Design --- p.37Chapter 3.2.1.1. --- Voltage Multiplier Branch for Generating Venv --- p.39Chapter 3.2.1.2. --- Voltage Multiplier Branch for Generating Vref --- p.41Chapter 3.2.2. --- Design Considerations for Sensitivity of ASK Demodulator --- p.41Chapter 3.2.3. --- RF Input Power Sharing with Voltage Multiplier --- p.44Chapter 3.2.4. --- ASK Demodulator and Voltage Multiplier Integrated Estimations for Maximum RF Power Input --- p.47Chapter 3.2.5. --- Measurement result and Discussion --- p.49Chapter 3.3. --- Proposed Envelope Detector Circuit --- p.52Chapter 3.3.1. --- Sensitivity Estimation --- p.52Chapter 3.3.2. --- Maximum Tolerable Input Power Estimation --- p.53Chapter 3.3.3. --- Envelope Waveform Recovery of the Proposed Envelope Detector --- p.54Chapter 3.4. --- Summary --- p.57Chapter 3.5. --- References --- p.58Chapter 4. --- Clock Generator for EPC C-l G-2 Transponder --- p.59Chapter 4.1. --- Design Challenges Overview of Clock Generator --- p.59Chapter 4.2. --- Brief Review of PIE Symbols in EPC C1G2 Standard --- p.62Chapter 4.3. --- Proposed Clock Recovery Circuit Based on PIE Symbols for Clock Frequency Calibration --- p.64Chapter 4.3.1. --- Illustration on PIE Symbols for Clock Frequency Calibration --- p.64Chapter 4.3.2. --- Symbol time-length counter --- p.72Chapter 4.3.3. --- The M2.56MHZ Reference Generator and Sampling Frequency Requirement --- p.75Chapter 4.3.4. --- Symbol Length Reconfiguration for Different Tari and FLL Stability --- p.80Chapter 4.3.5. --- Frequency Detector and Loop Filter --- p.83Chapter 4.3.6. --- Proposed DCO Design --- p.84Chapter 4.3.7. --- Measurement Results and Discussions --- p.88Chapter 4.3.7.1. --- Frequency Calibration Measurement Results --- p.89Chapter 4.3.7.2. --- Number x and Tari Variation --- p.92Chapter 4.3.7.3. --- Temperature and Supply Variation --- p.93Chapter 4.3.7.4. --- Transient Supply Variation --- p.94Chapter 4.3.8. --- Works Comparison --- p.95Chapter 4.4. --- Clock Generator with Embedded PIE Decoder --- p.96Chapter 4.4.1. --- Clock Generator for Transponder Review --- p.96Chapter 4.4.2. --- PIE Decoder Review --- p.97Chapter 4.4.3. --- Proposed Clock Generator with Embedded PIE Decoder --- p.97Chapter 4.4.4. --- Measurement Results and Discussions --- p.100Chapter 4.5. --- Summary --- p.103Chapter 4.6. --- References --- p.105Chapter 5. --- ASK Modulator --- p.107Chapter 5.1. --- Introduction to ASK Modulator in RFD Transponder --- p.107Chapter 5.2. --- ASK Modulator Design --- p.109Chapter 5.3. --- ASK Modulator Measurement --- p.110Chapter 5.4. --- Summary --- p.113Chapter 5.5. --- References --- p.113Chapter 6. --- Conclusions --- p.114Chapter 6.1. --- Contribution --- p.114Chapter 6.2. --- Future Development --- p.11

Ultra Low Power IEEE 802.15.4/ZIGBEE Compliant Transceiver

Low power wireless communications is the most demanding request among all wireless users. A battery life that can survive for years without being replaced, makes it realistic to implement many applications where the battery is unreachable (e.g. concrete walls) or expensive to change (e.g underground applications). IEEE 802.15.4/ZIGBEE standard is published to cover low power low cost applications, where the battery life can last for years, because of the 1% duty cycle of operation. A fully integrated 2.4GHz IEEE802.15.4 Compliant transceiver suitable for low power, low cost ZIGBEE applications is implemented. Direct conversion architecture is used in both Receiver and Transmitter, to achieve the minimum possible power and area. The chip is fabricated in a standard 0.18um CMOS technology. In the transmit mode, the transmitter chain (Modulator to PA) consumes 25mW, while in the receive mode, the iv receiver chain (LNA to Demodulator) consumes 5mW. The Integer-N Frequency Synthesizer consumes 8.5mW. Other Low power circuits are reported; A 13.56 Passive RFID tag and a low power ADC suitable for Built-In-Testing applications

Nanopower CMOS transponders for UHF and microwave RFID systems

At first, we present an analysis and a discussion of the design options and tradeoffs for a passive microwave transponder. We derive a set of criteria for the optimization of the voltage multiplier, the power matching network and the backscatter modulator in order to optimize the operating range. In order to match the strictly power requirements, the communication protocol between transponder and reader has been chosen in a convenient way, in order to make the architecture of the passive transponder very simple and then ultra-low-power. From the circuital point of view, the digital section has been implemented in subthreshold CMOS logic with very low supply voltage and clock frequency. We present different solutions to supply power to the transponder, in order to keep the power consumption in the deep sub-µW regime and to drastically reduce the huge sensitivity of the subthreshold logic to temperature and process variations. Moreover, a low-voltage and low-power EEPROM in a standard CMOS process has been implemented. Finally, we have presented the implementation of the entire passive transponder, operating in the UHF or microwave frequency range

Flexible Evaluation of RFID System Parameters using Rapid Prototyping

Abstract-Today's RFID systems are dependent on a wide range of different parameters, that influence the overall performance. Such system parameters can for example be the selected data rate, encoding scheme, modulation setting, transmit power or different hardware configurations, like one or two antenna scenarios. Furthermore, it is often desired to optimise several performance goals, like read-out range, read-out quality, throughput, etc., which are often contradicting each other. In order to achieve a desired performance of an RFID system, it is essential to understand the influences of the individual parameters of interest and their interconnection. Due to the multitude, wide range and interdependencies of influencing factors, this however is a complex task. Simulations offer insights in these relations but rely on the correct modeling of the dependencies of-and between the parameters. With our established prototyping system for RFID, we are able to flexibly and accurately explore the influence and interconnection of such parameters in a wide range on a basis of real-time measurements. Results on the evaluation of read-out quality depending on the transmit power and the data rate are presented

Generalized Model to Enable Zero-shot Imitation Learning for Versatile Robots

The rapid advancement in Deep Learning (DL), especially in Reinforcement Learning (RL) and Imitation Learning (IL), has positioned it as a promising approach for a multitude of autonomous robotic systems. However, the current methodologies are predominantly constrained to singular setups, necessitating substantial data and extensive training periods. Moreover, these methods have exhibited suboptimal performance in tasks requiring long-horizontal maneuvers, such as Radio Frequency Identification (RFID) inventory, where a robot requires thousands of steps to complete. In this thesis, we address the aforementioned challenges by presenting the Cross-modal Reasoning Model (CMRM), a novel zero-shot Imitation Learning policy, to tackle long-horizontal robotic tasks. The RFID inventory task is a typical long-horizontal robotic task that can be formulated as a Partially Observable Markov Decision Process (POMDP); the robot should be able to recall previous actions and reason from current environmental observations to optimize its strategy. To this end, our CMRM has been designed with a two-stream flow structure to extract abstract information concealed in environmental observations and subsequently generate robot actions by reasoning structural and temporal features from historical and current observations. Extensive experiments in a virtual platform and mockup real store are conducted to evaluate the proposed CMRM. Experimental results demonstrate that CMRM is capable of performing RFID inventory tasks in unstructured environments with complex layouts and provides competitive accuracy that surpasses previous methods and manual inventory. To facilitate the training and assessment of CMRM, we constructed a Unity3D-based virtual platform that can be configured into various environments, like an apparel store. This platform is capable of offering photo-realistic objects and precise physical features (gravities, appearance, and more) to provide close to real environments for training and testing robots. Subsequently, the robot, once trained, was deployed in an actual retail environment to perform RFID inventory tasks. This approach effectively bridges the ``reality gap , enabling the robot to perform the RFID inventory task seamlessly in both virtual and real-world settings, thereby demonstrating zero-shot generalization capabilities

Entwurf und Implementierung von Verfahren und Algorithmen in Transponderlesegeräten zur Optimierung der Übertragungseigenschaften von LF-Transpondersystemen

Das Ziel dieser Arbeit liegt in der Optimierung der Übertragungseigenschaften von Low-Frequency-Transponderlesegeräten. Der Fokus liegt auf der Entwicklung von neuen Verfahren und Algorithmen, die eine stabile Energie- und Datenübertragung mobiler Lesegeräte unter variierenden Umgebungseinflüssen ermöglichen. Besonders bei passiven Sensortranspondern, die zusätzlich zu einer Identifikationsnummer Messdaten an das Lesegerät übermitteln, stellt die Energieversorgung des Transponderchips und des Sensors eine Herausforderung dar. Um den Sensortransponder über das magnetische Feld mit ausreichend Energie zu versorgen, können mobile, akkubetriebene Lesegeräte für eine verbesserte Energieeffizienz mit einer Lesegerätespule hoher Güte versehen werden. Jedoch wird das Datensignal in einem Transpondersystem mit einer Lesegerätespule hoher Güte stark verzerrt und somit die Detektion der empfangenen Daten erschwert. Des Weiteren ist es insbesondere bei variierenden Umgebungseinflüssen schwierig, eine stabile Energieversorgung zu gewährleisten, weil die Übertragung der Energie - genau wie die der Daten - unter anderem von Parametern abhängig ist, die durch die Umgebung der Antennenspulen bestimmt werden. Dies konnte bereits mit Messungen des Basisbandsignals oder von Übertragungsfunktionen dokumentiert werden. Darüber hinaus existieren diverse Ansätze, um ein Transpondersystem zu simulieren. Die Verfahren nach dem Stand der Technik umgehen die Problematik variierender Übertragungsfunktionen maßgeblich durch den Einsatz von Antennenspulen niedriger Güte oder analogen Schaltungen, die die Übertragung für bestimmte Rahmenbedingungen stabilisieren sollen. Antennenspulen hoher Güte werden aufgrund diverser auftretender Probleme kaum eingesetzt. Im Rahmen dieser Arbeit ist ein System gesucht, das sich bei Änderungen der Ausgangsbedingungen, sei es bei den Eigenschaften der Antennenspulen oder bei den äußeren Einflüssen, an die neue Umgebung adaptieren kann. Dabei wird die Frage untersucht, in welcher Art die variierenden Einflüsse, die von Bedeutung sind, simuliert werden können und wie das System auf dieser Basis optimiert werden kann. Die Erkenntnisse fließen in die Entwicklung adaptiver Verfahren und Algorithmen für das Hardware-Front-End sowie für die digitale Signalverarbeitung ein. Die Übertragungsfunktionen des Transpondersystems werden in einem Modell, welches die äußeren Einflüsse auf die Antennen als variable Parameter mit einbezieht, in Matlab/Simulink simuliert. Ein Vergleich mit Messungen verschiedener Übertragungsfunktionen im Transpondersystem zeigt die Zuverlässigkeit des Modells. Das verzerrte Basisbandsignal wurde zusammen mit anderen Signalen am Lesegeräte-Front-End auf Informationen untersucht, die eine Aussage über die Zuverlässigkeit des erkannten Symbols enthalten, welche in den Detektionsalgorithmen verwendet werden kann. Weiterhin wird ein Demonstrator eines adaptiven Kernmoduls für mobile Transponderlesegeräte vorgestellt. Dieser besteht aus einem digital gesteuerten analogen Front-End und einem FPGA, der von Matlab aus gesteuert werden kann. Mit Hilfe von digitaler Signalverarbeitung können in Kombination mit der dafür ausgelegten Hardware die Energieversorgung sowie die Datendetektion signifikant verbessert werden. Die im Rahmen dieser Arbeit entwickelten Verfahren sind energieeffizient, adaptierbar und mit geringem Hardwareaufwand zu implementieren. Bei der Decodierung von Basisbandsignalen, die mit Antennenspulen hoher Güte empfangen worden sind, kann die Bitfehlerrate gegenüber Maximum-Likelihood-Verfahren aus dem Stand der Low-Frequency-Transpondertechnik deutlich verringert werden. Durch Signalverarbeitung wird auch die Energieversorgung stabilisiert. Mit einem Verfahren zur Trägerfrequenzadaption wird je nach Umgebungseinfluss eine signifikant bessere Energieversorgung als mit adaptiven Verfahren nach dem Stand der Technik erreicht

A self-powered single-chip wireless sensor platform

Internet of things” require a large array of low-cost sensor nodes, wireless connectivity, low power operation and system intelligence. On the other hand, wireless biomedical implants demand additional specifications including small form factor, a choice of wireless operating frequencies within the window for minimum tissue loss and bio-compatibility This thesis describes a low power and low-cost internet of things system suitable for implant applications that is implemented in its entirety on a single standard CMOS chip with an area smaller than 0.5 mm2. The chip includes integrated sensors, ultra-low-power transceivers, and additional interface and digital control electronics while it does not require a battery or complex packaging schemes. It is powered through electromagnetic (EM) radiation using its on-chip miniature antenna that also assists with transmit and receive functions. The chip can operate at a short distance (a few centimeters) from an EM source that also serves as its wireless link. Design methodology, system simulation and optimization and early measurement results are presented

Integration and validation of a radio frequency identification (RFID) system and automatic sorting technology (AST) for real-time correlation of management and disease impacts on the performance of swine in field studies

A cohort study using RFID system with automatic sorting scales to monitor weights of swine finishers was conducted. Weight data from 2,057 barn-raised pigs were monitored to assess tag retention, frequency of scale visits, data capture, and outlier detection. Results showed tag loss rate highest around 12th and 13th week of finishing; crowded pens more likely to lose tags; and pen-averaged daily scale visits ranged from 2.45-2.74 visits. Using a system that removes outliers and inaccurate weights, weight data from 100 randomly selected swine finishers in four time-points were evaluated. Sample pigs were bled monthly for three months, tested for PRRS virus infection using ELISA and RT-PCR, and grouped based on test results. Repeated measures analysis revealed significant interaction between group and time (P=0.014). The group (2 head) with the largest mean final weight (224.38 +/- 14.79) was negative in both tests while the group (28 head) with the lowest mean final weight 207.56 +/- 4.29 was positive in either test for three time-points