Antennas and Wireless Sensors
(Figure: Joni Kurvinen, Anu Lehtovuori, Jianchun Mai, Chao Wang, and Ville Viikari, "Metal-covered Handset with LTE MIMO, Wi-Fi MIMO, and GPS Antennas", Progress In Electromagnetics Research C, Vol. 80, 89–101, 2018)
We are surrounded by wireless devices. Our research focuses on wireless link including antennas to transmit and receive electromagnetic waves and the propagation of these waves in different environments.
There are three main research areas in the field of Antennas and propagation:
Current antennas of mobile phones can waste up to 99 % of available RF energy for heating up the user and the device. We study adaptive antennas consisting of many, collaborative radiating elements making it possible to adapt the antennas operation to the given frequency and mitigate losses due to the user. See a 1-minute youtube video on the concept (https://youtu.be/1IcNtoTL00k). We also develop beam-steerable mm-wave antennas for mobile devices. In particular, we study how these antennas could share the same volume with LTE antennas.
Compared to microwaves, mm-waves makes it possible to focus radio waves much better with antennas of the same size. We study how to best realize mm-wave beam-steerable antennas and our research is related for instance to wide-band arrays with wide beam steering range, mitigation of active reflection, integration of active electronics with passive antenna structures, usage of novel materials in mm-wave antennas and manufacturing of the antennas with 3D printing technologies.
We study RF-powered devices that can harvest the required energy from ambient radio waves and use the same waves for communication too. We focus our research in particular in adaptive antennas, power harvesters, modulators and sensors.
Combinatory Feeding Method for Mobile Applications
Tunable eight-element MIMO antenna based on the antenna cluster concept
Unbroken Metal Rim MIMO Antenna Utilizing Antenna Clusters
Millimeter-wave imaging method based on frequency-diverse subarrays
Millimeter-wave antennas for mobile devices and networks
Coupling of Characteristic Modes on PEC and Lossy Dielectric Structures
Beneficial Interaction of Coupling and Mismatch in a Two-Antenna System
Integrated Metal-lens Antennas with Reduced Height at 71-76 GHz
Wide-angle Impedance Matching of Antenna Arrays with Circuit Synthesis and Optimization Tools
Bluetooth Antenna for Smart Jewellery with Metal Covers
Associate Professor Ville Viikari
Email: [email protected]
Tel.: +358 50 4135 458
Department of Electronics and Nanoengineering
Aalto University School of Electrical Engineering
P.O. Box 15500, 00076 Aalto, Finland
Maarintie 8, 02150 Espoo