This book presents state-of-the-art trends in reconfigurable active and passive planar antennas and their applications in wireless communication systems operating in the frequency band 5-6 GHz. Due to various key features such as multifunction antenna design, compactness, planar nature, and low cost, these technologies are becoming popular for current and future wireless applications. This book discusses different novel antenna designs and their working principles in detail. The modern and future wireless systems require wideband antennas to accommodate various channels in a single band or in separate bands. The carrier aggregation (CA) has been introduced in the modern wireless systems such as LTE-advanced systems and 5G./6G. In CA, a device can use several channels for transmission and reception. The used channels can exist in the same frequency band (intra-band CA) or in distinct bands (inter-band CA). To accommodate more channels, more bandwidth is required within the operatingband. For portable devices, circularly polarized (CP) antennas are more advantageous over linearly polarized antennas since in CP antennas, there is low risk of misalignment and, hence encountering interference. Circularly polarized antenna also provides higher link reliability for the portable devices. To provide high data rates, more bandwidth is needed to accommodate more channels. Various multifunction, compact, and wideband antennas for plethora of applications are addressed in detail in this book. The scope of developing reconfigurable active antennas for application in beam switching, beam steering, wireless charging, security systems, etc., is described. This book concludes by giving glimpses of antenna requirements for future wireless communication systems.

Autorentext

Shiban K Koul is an Emeritus Professor at the Indian Institute of Technology, Delhi. His research interests include: RF MEMS, High Frequency Wireless Communication, Microwave Engineering, Microwave Passive and Active Circuits, Device modeling, Millimeter wave IC Design, and Reconfigurable Microwave Circuits including Antennas. He has successfully completed 38 major sponsored projects, 52 consultancy projects and 60 technology development projects. He has authored 475 research Papers, 12 state-of-the art Books, 3 Book Chapters and 2 E-books. He holds 13 patents and 6 copyrights. He is a Life Fellow of IEEE and Fellow of INAE and IETE. He is the Chief Editor of IETE Journal of Research and Associate Editor of the International Journal of Microwave and Wireless Technologies, Cambridge University Press. He served as a Distinguished Microwave Lecturer of IEEE MTT-S for the period 2012-2014. He is recipient of numerous awards including IEEE MTT Society Distinguished Educator Award (2014) and Teaching Excellence Award (2012) from IIT Delhi etc. Rajesh K Singh received his Ph.D. degree in microwave engineering from the Indian Institute of Technology, Delhi, India in 2018. He is currently a Post-Doctoral Researcher at the Microwave and Radiation Laboratory, Department of Information Engineering, University of Pisa, Pisa, Italy. His current research interests include the development of active integrated antennas, reconfigurable antennas for current and future communication systems and glove integrated antennas for near field UHF-RFID readers. He has authored more than 25 international journal articles and conference contributions. He served as Chairman (2016-2018) of the IEEE MTT-S Student Branch Chapter of Indian Institute of Technology Delhi, India. Dr. Singh is a recipient of the Young Scientist Award for the International Union of Radio Science (URSI) General Assembly and Scientific Symposium (GASS)2020.