by John Doe (INPT ENSEEIHT, France)
The mobility and Internet of Things (IoT) explosion has led to a severe wireless spectrum shortage which led to seeking new ways to alleviate the bandwidth crunch. Globally, wireless devices are becoming pervasive and consume network capacity and bandwidth at accelerated rates. Fourth generation (4G) networks based on the Long Term Evolution (LTE) offers significant upgrades over 3G in terms of data throughput. However, despite expected performances of future LTE-Advanced, with continuous increase in the mobile data traffic one has to put a significant long term crunch on both network capacity and bandwidth.
Indeed, mobile networks will increasingly become the primary means of network access from person-to-person and person-to–machine connectivity. It will provide the fundamental infrastructure for building smart cities which will push mobile networks performances and capability requirements to their extremes. It will be a key component of the networked society and will help realize the vision of essentially unlimited access to information and sharing of data anywhere and anytime for anyone and anything.
Next generation of mobile network (5G) will therefore not only be about mobile connectivity for people. Rather, the aim of 5G is to provide ubiquitous connectivity for any kind of device and any kind of application that may benefit from being connected. Thereby, It will provide wireless connectivity for a wide range of new applications and use cases with vastly different characteristics and requirements, including wearables, smart homes, traffic safety/control, and critical infrastructure and industry applications, as well as for very-high-speed media delivery. To do so, the capabilities of 5G wireless access must extend far beyond those of previous generations of mobile communication. Therefore, deployment of novel generation of communication systems requires necessary breakthrough in advanced-RF domain. This will bring benefits to the efficient and flexible usage of spectrum.
One of the most important keyword in the design of future systems in the 5G era is flexibility. One has to develop systems with multiple standards which differ from center frequencies, bandwidth and number of useful bands. The design of tunable systems is henceforth primordial in future generation of communication, as it is the case since many years at RF frequencies. It is therefore a key issue for cost and size reduction. Indeed, the use of tunable systems minimizes the number of needed equipment, since only one function can address all or part of the useful bands. Moreover, such systems have to adapt their data rates depending on the demand, and they will contribute to consumption significant reduction. Thereby, the study of implementation of agile sub-mm-wave front-ends will be in the next future a booming topic of interest. However, for future generation of systems, the frequency deviation will be important as the operating frequencies may vary from a few tens of GHz to beyond 100 GHz. Thereby, the challenge is to be able to control the system performance regardless of its operating frequency and to maintain acceptable level of electrical performances over the entire tuning range.
Within this context, one has to define novel architectures for tunable systems as well as novel topologies and design techniques for tunable functions especially for passive functions such as filters whose specifications are more and more constrained in terms of selectivity and insertion loss. Solution will be proposed in SiGe based CMOS technologies which provided good electrica performance for active devices, in terms of FT/Fmax of transistors, but has poor quality factor for passive implementation.
Gaetan Prigent was born on december 2, 1973 in Lannion, France. He received his Ph.D. degree in electronic from the University of Brest, Brest, France, in 2002. He was with the Laboratory for Electronics and Telecommunication Systems (LEST), Laboratory of Brest, Brest, France until 2004. Since 2004, he has been with the Electronic Laboratory, Institut National Polytechnique de Toulouse (INPT), Toulouse, France. In 2009, he joined the Laboratory for Plasma and Energy Conversion (LAPLACE). In 2011 he has obtained the peer accreditation to supervise research. He is currently an Associate Professor of electronics with the Institut National Polytechnique de Toulouse (INPT), Toulouse, France. Since 2011 he is head of the Electronic and signal processing department at the Ecole Nationale Supérieure d’Electrotechnique, d’Electronique, d’Informatique, d’Hydraulique et de Télécommunications (ENSEEIHT), Toulouse, France. His research principally concerns the design of passive microwave devices, especially planar filters for millimeter- and submillimeter-wave applications beyond 100-GHz He is working toward the design of MEMs-based tunable circuits and systems integrated is silicon-based technologies (Si-BCB, Si membranes, SOI, BiCMOS, SiGe). His research activities also concern the development of novel filter topologies and associate synthesis. He was the supervisor of 8 Ph-D students and 1 post-doc. He is the author and co-author of 27 journal papers and more than 100 papers in conference proceedings. He is also author/co-author of three book chapters He has been invited speaker for 6 international conferences. He is TPC member of six IEEE conferences. In 2013 he was the general chair of the 9th International Summer School on RF-MEMS and RF Microsystems, Toulouse, France. He was a member of the organizing committee and general chair of interactive sessions of 2015 EuMA European Microwave Conference (EuMW), Paris.