IEEE MTT-S 2008 International Microwave Symposium Technical Program

Session: WE4C	Tags and Sensors
Chair:	Alan Jenkins, Tycoelectronics
Co-Chair:	Hiroshi Kondoh, Hitachi
Abstract:	his session will review both RFID concepts and sensors for physical measurement systems, with particular emphasis on addressing system architecture and tag realizations for RFID applications that improve the tag read-range under various deployment scenarios.

WE4C-01	Complex Signal Demodulation and Random Body Movement Cancellation Techniques for Non-contact Vital Sign Detection
1314	C. Li, J. Lin, University of Florida, Gainesville, United States
	A complex signal demodulation technique is proposed to eliminate the null detection point problem in non-contact vital sign detection. This technique is robust against DC offset in direct conversion system. Based on the complex signal demodulation, a random body movement cancellation technique is developed to cancel out strong noise caused by random body movement in non-contact vital sign monitoring. Multiple transceivers and antennas with polarization and frequency multiplexing are used to detect signals from different body orientations. The noise due to random body movement is cancelled out based on different patterns of the desired and undesired signals. Experiments by highly compact 5-6 GHz portable radar systems have been performed to verify these two techniques.

WE4C-02	Regenerative Backscatter Transponder using the Switched Injection-Locked Oscillator Concept
1313	M. Vossiek¹, T. Schaefer¹, D. Becker², ¹Clausthal University of Technology, Clausthal-Zellerfeld, Germany, ²Symeo GmbH, Neubiberg / Munich, Germany
	In this paper, a new backscatter transponder type is introduced. The developed transponder regenerates a modulated, phase-coherent high-power response/ replica to an interrogating CW radar signal. To create the amplified phase-coherent transponder response, the switched injection locked oscillator (SILO) concept is applied. Compared with a usual passive backscatter transponder – known e.g. from UHF RFID systems – the reading range of a SILO transponder is substantially increased. It is demonstrated that a reading range above 20 m is easily obtained even with a 5.8 GHz, 15 MBit/s system.

WE4C-03	A Smart Beam Steering RFID Interrogator For Passive Tags in Item Level Tagging Applications
1757	M. Y. Chia, K. C. Ang, K. Chee, S. Leong, Institute for Infocomm Research, Singapore, Singapore
	Item level tagging is a challenge for low cost and passive RFID tags since these are closely packed in the operating environment. Passive tags suffers from poor reading rates using existing RFID interrogators with limited capability on tags and interrogator. In this paper, we have proposed a low cost electronic beamsteering method which enable existing RFID interrogator to be “smarter” by reconfiguring its RF beam adaptively and yet maintain high angular resolution. Little changes to existing transceiver is required to minimize costs since only its external reference clock is enable by direct digital synthesizer (DDS) as a variable reference time delay. The new RFID transceiver system is designed at ISO standards at UHF bands. Experimental results show that it is able to read at least twice as many passive tags, as compared to the conventional beam-switching system

WE4C-04	A Dual-Resonant Microstrip-Based UHF RFID "Cargo" Tag
1175	S. R. Aroor, D. D. Deavours, Information and Telecommunications Technology Center, Univeristy of Kansas, Lawrence , United States
	We present a novel passive UHF RFID "cargo" tag capable of operating in two different graphic regions such as Europe and North America. The tag utilizes a dual-resonant, dual-polarized, microstrip antenna. The resulting tag operates efficiently over ETSI and FCC frequency ranges and achieves excellent efficiency. The tag antenna eliminates any cross layer structures such as a via and may be manufactured efficiently using traditional, low-cost "inlay" technology. We estimate the free-space read distance to be between 9.3 and 13.1 meters( 30 and 43 feet)

WE4C-05	Miniaturized Patch Antenna for the Radio Frequency Identification of Metallic Objects
1569	A. Ghiotto¹, S. F. Cantalice², T. Vuong¹, A. Pouzin¹, G. Fontgalland², S. Tedjini¹, ¹Grenoble INP, Valence, France, ²Federal University of Campina Grande, Campina Grande, Brazil
	The growing interest in the Radio Frequency Identification (RFID) technology is giving rise to new applications, in particular for the identification of metallic objects. This interest has initiated the development of new designs for RFID tag antenna. This paper presents a UHF miniaturized patch antenna aimed at this application. The patch antenna is fed by a balanced feed to avoid a cross-layered construction and matched with a stub. Its miniaturization is achieved by inserting a u-shaped slot in the radiating patch.

If you encounter any problems, please contact