ECEE Seminar Series Spring 2015 Thursday, January 29, 2015 11:00 am – 12:15 pm ECEE 1B32 Energy harvesting and wireless power transfer towards autonomous wireless sensors and RFID's Abstract: Apostolos Georgiadis Energy harvesting and wireless power transfer are important technologies which enable extending the energy autonomy and operating range of wireless sensors and radio frequency identification (RFID) tags. In this talk recent advances towards maximizing the power transfer efficiency of such systems are presented. Challenges are identified in terms of operating power levels, operating frequency and bandwidth, and energy and load variation in rectifier and rectenna circuits. Multiple technology energy harvesters are discussed and the development of low profile and conformal solar antennas, as well as solar–electromagnetic harvesters and solar-thermal antennas is presented. Circuit examples including prototypes based on textile materials and inkjet-printed circuits on paper and plastic substrates will be shown. Energy harvesting assisted RFID systems are discussed where the operating range of passive UHF RFID tags can be extended through the use or ambient energy sources. Finally, the effect of signal properties in the performance of wireless power transfer systems is discussed and the use of time varying envelope signals such as modulated, white noise and chaotic signals as potential signal candidates leading to optimum rectifier RF-DC conversion efficiency performance is presented. Biography: Apostolos Georgiadis was born in Thessaloniki, Greece. He received his B.Sc. degree in physics and M.Sc. degree in telecommunications from the Aristotle University of Thessaloniki, Greece, in 1993 and 1996, respectively. He received his Ph.D. degree in electrical engineering from the University of Massachusetts at Amherst, in 2002. In 2007, he joined Centre Tecnològic de Telecomunicacions de Catalunya (CTTC), Barcelona, Spain, as a Senior Researcher, where he is involved in energy harvesting and radiofrequency identification (RFID) technology and active antennas and antenna arrays. Since Apr. 2013 he is Group Leader of the Microwave Systems and Nanotechnology Department at CTTC. He was the Chair of the 2011 IEEE RFID Technologies and Applications (RFID-TA) Conference. He serves as an Associate Editor of the IEEE Microwave Wireless Components Letters and IET Microwaves Antennas and Propagation journals. He is Member of the MTT-S Technical Committee TC-24 on RFID Technologies and member of TC-26 on wireless energy transfer and conversion. He is Editor-in-Chief of the Wireless Power Transfer journal published by Cambridge University Press. He is Vice-Chair of URSI Commission D. Light refreshments will be served.