Communication Subsystems for Emerging Wireless Technologies

The paper describes a multi-disciplinary design of modern communication systems. The design starts with the analysis of a system in order to define requirements on its individual components. The design exploits proper models of communication channels to adapt the systems to expected transmission conditions. Input filtering of signals both in the frequency domain and in the spatial domain is ensured by a properly designed antenna. Further signal processing (amplification and further filtering) is done by electronics circuits. Finally, signal processing techniques are applied to yield information about current properties of frequency spectrum and to distribute the transmission over free subcarrier channels

Design And Implementation Of An X-Band Passive Rfid Tag

This research presents a novel fully integrated energy harvester, matching network, matching network,matching network, matching network,matching network, matching network, matching network, multi-stage RF-DC rectifier, mode selector, RC oscillator, LC oscillator, and X-band power amplifier implemented in IBM 0.18-µm RF CMOS technology. We investigated different matching schemes, antennas, and rectifiers with focus on the interaction between building blocks. Currently the power amplifier gives the maximum output power of 5.23 dBm at 9.1GHz. The entire RFID tag circuit was designed to operate in low power consumption. Voltage sensor circuit which generates the enable signal was designed to operate in very low current. All the test blocks of the RFID tag were tested. The smaller size and the cost of the RFID tag are critical for widespread adoption of the technology. The cost of the RFID tag can be lowered by implementing an on-chip antenna. We were able to develop, fabricate, and implement a fully integrated RFID tag in a smaller size (3 mm X 1.5 mm) than the existing tags. With further modifications, this could be used as a commercial low cost RFID tag

125 kHz RFID READER DESIGN

The aim of this Final Year Project (FYP) is to develop a low cost RFID system to be an alternative to the expensive option. RFID system composed of RFID tags and reader. This project focuses on developing the RFID reader. There are four sub-blocks of RFID architecture namely, transmit stage, rectangular coil antenna, receiving section and microcontroller part

RFID Transponders' RF Emissions in Aircraft Communication and Navigation Radio Bands

Radiated emission data in aircraft communication and navigation bands are presented for several active radio frequency identification (RFID) tags. The individual tags are different in design, operation and transmitting frequencies. The process for measuring the tags emissions in a reverberation chamber is discussed. Measurement issues dealing with tag interrogation, low level measurement in the presence of strong transmissions, and tags low duty factors are discussed. The results show strong emissions, far exceeding aircraft emission limits and can be of potential interference risks

RADIO FREQUENCY IDENTIFICATION OF PERSONNEL IN PLANT DURING EMERGENCY CONDITIONS

Nowadays, nearly every industrial plant throughout the nation are taking concern on the emerging safety issues that is seemed to be more apparent - compared to just taking serious attention to the production line. It's been said that if you think safety is expensive, try an accident. Safety of each personnel is deeply linked on the psychological part that contributes to the well being of an industrial plant andtherefore the workers are part of the valuable assets to the company. Parallel to the development of industrial competency and complexity, the safety issues have becoming more technologically related. RFID (Radio Frequency Identification), already known for its agility and reliability in supply chain management, has now being diverging in areas regarding safety. RFID is not just a label that tags for certain equipments / goods, but now able to detect location of moving object, especially human, in an enclosed area. From simulation upto practical application, RFID had shown significant improvement for a faster and precise detection of personnel compared to other traditional barcode detection or manual head count to ensure safety evacuation of all personnel during emergency

Spatial Identification Methods and Systems for RFID Tags

Disertační práce je zaměřena na metody a systémy pro měření vzdálenosti a lokalizaci RFID tagů pracujících v pásmu UHF. Úvod je věnován popisu současného stavu vědeckého poznání v oblasti RFID prostorové identifikace a stručnému shrnutí problematiky modelování a návrhu prototypů těchto systémů. Po specifikaci cílů disertace pokračuje práce popisem teorie modelování degenerovaného kanálu pro RFID komunikaci. Detailně jsou rozebrány metody měření vzdálenosti a odhadu směru příchodu signálu založené na zpracování fázové informace. Pro účely lokalizace je navrženo několik scénářů rozmístění antén. Modely degenerovaného kanálu jsou simulovány v systému MATLAB. Významná část této práce je věnována konceptu softwarově definovaného rádia (SDR) a specifikům jeho adaptace na UHF RFID, která využití běžných SDR systémů značně omezují. Diskutována je zejména problematika průniku nosné vysílače do přijímací cesty a požadavky na signál lokálního oscilátoru používaný pro směšování. Prezentovány jsou tři vyvinuté prototypy: experimentální dotazovač EXIN-1, měřicí systém založený na platformě Ettus USRP a anténní přepínací matice pro emulaci SIMO systému. Závěrečná část je zaměřena na testování a zhodnocení popisovaných lokalizačních technik, založených na měření komplexní přenosové funkce RFID kanálu. Popisuje úzkopásmové/širokopásmové měření vzdálenosti a metody odhadu směru signálu. Oba navržené scénáře rozmístění antén jsou v závěru ověřeny lokalizačním měřením v reálných podmínkách.The doctoral thesis is focused on methods and systems for ranging and localization of RFID tags operating in the UHF band. It begins with a description of the state of the art in the field of RFID positioning with short extension to the area of modeling and prototyping of such systems. After a brief specification of dissertation objectives, the thesis overviews the theory of degenerate channel modeling for RFID communication. Details are given about phase-based ranging and direction of arrival finding methods. Several antenna placement scenarios are proposed for localization purposes. The degenerate channel models are simulated in MATLAB. A significant part of the thesis is devoted to software defined radio (SDR) concept and its adaptation for UHF RFID operation, as it has its specialties which make the usage of standard SDR test equipment very disputable. Transmit carrier leakage into receiver path and requirements on local oscillator signals for mixing are discussed. The development of three experimental prototypes is also presented there: experimental interrogator EXIN-1, measurement system based on Ettus USRP platform, and antenna switching matrix for an emulation of SIMO system. The final part is focused on testing and evaluation of described positioning techniques based on complex backscatter channel transfer function measurement. Both narrowband/wideband ranging and direction of arrival methods are validated. Finally, both proposed antenna placement scenarios are evaluated with real-world measurements.

RFID SIMULATION IN MATLAB I SIMULINK

Nowadays, Radio Frequency Identification (RFID) applications are widely used in daily application and also in industries. RFID is an automatic identifications method, relying on storing and remotely retrieving data using devices called RFID tags or transponders. The RFID tag is an object that can be placed into a product or person for the purpose of identification using radio waves. RFID uses wireless communication technique, found application in many areas such as attendance tracking system in campus or in a big factory and also for inventory tracking and management. In this project, the work of Yifen Han, Qiang Li and Hao Min from Auto-ID Labs at Fudan University, Shanghai, China will be reproduced so that further simulation result can be generated. Special attention is emphasized on the development of transmitter, receiver, wireless channel and tag for the system simulation environment because these four elements are the most important subsystems to produce an RFID simulation environment. This project will evaluate the system performance by changing the coding method and operation distance. At this point, half of transmitter subsystems have been done. The subsystems developed so far are source coding, raised cosine Hilbert and digital to analog converter