HELSINKI UNIVERSITY OF TECHNOLOGY

Transcription

1 SMARAD : Smart and Novel Radios Research Unit : Centre of Excellence in Smart Radios and Wireless Research 1

2 People About 90 people 7 professors (5 PI s) 25 other senior level researchers with a doctor degree About 40 post-graduate students aiming at the doctor degree; some 20 % of them females Personnel truly international: more than 10 nationalities represented among permanent staff and post-graduate students 2

3 Facilities RF, microwave, mm-wave and submm-wave measurement equipment e.g. vector network analyzers up to 700 GHz Special antenna and channel measurement facilities MIMO measurements, planar near-field scanner, hologram CATR Shielded rooms, anechoic chambers Simulation and design software Mentor Graphics, Cadence, Synopsys, Aplac, ADS, HSPICE, HFSS, XFDTD, SEMCAD, IE3D, etc. Powerful computing platforms including super computers at CSC 3

4 Academic excellence Over the period of , the participating groups produced: 273 peer-reviewed international scientific journal papers 551 peer-reviewed international conference papers 20 book chapters 9 text books 30 patents 35 doctors (in 2006: 12 doctors!) Several best paper awards, etc. 4

5 SMARAD Prof. Antti Räisänen Secretary/office Anne Jääskeläinen Millimeter wave and THz techniques Prof. Antti Räisänen (AR) Artificial electromagnetic materials and applications Prof. Sergei Tretyakov (ST) High-frequency and microwave engineering Prof. Pertti Vainikainen (PV) Communications and statistical signal processing Prof. Visa Koivunen (VK) Electronic circuit design Prof. Kari Halonen (KH) 5

6 Contributions to smart radios and wireless research by each research area Antenna element design Antenna array design Novel EM mat. Radio electronics Cognitive radio Multiantenna (MIMO) comms Antenna and ch. meas. tech. Applicat. Artificial mater. X X X X X X RF and microwave mm-wave X X X X X X X X X X X X X X Signal proc. X X X X X X Circuit design X X X X X X 6

7 Artificial electromagnetic materials and applications Artificial materials (metamaterials) with unusual and extreme electromagnetic properties Controllable, non-linear, and active metamaterials New designs for antennas and microwave devices New designs for terahertz and optical devices (imaging, detection, superlenses...) Nano-scale composite materials 7

8 Antennas for cellular base stations Prototype of a base station antenna utilizing a loaded wire medium lens 8

9 Other activities: Organizing and leading the international Virtual Institute on Metamaterials Setting up a new international Congress on Advanced Electromagnetic Materials for Microwaves and Optics and a new journal 9

10 mm-wave and THz Antenna measurement techniques Hologram CATR demonstration at submm-wavelengths Error correction techniques, optimal near field scanning techniques, phase retrieval techniques, etc. Signal processing algorithms for adaptive arrays in case of antenna pattern correction 10

11 Electronic beam steering Needed in: Electronically adjustable point-to-point radio link antenna Anti-collision automotive radars 77 GHz Beam steering Our solution: With MEMS HIS reflectors With MEMS HIS based waveguide phase shifters Source Horn antenna Lens Plane wave ~ HIS 11

12 Antenna solutions for multi-system terminals The non-resonant broadband antenna element technique developed in SMARAD provides a basis for the development of minimumvolume antenna structures for multiple radios Mm-wave integrated MIMO radios: - Broadband multiradio antenna element - Volume about 1 cm 3 Area < 1 cm 2 Relative bandwidth [%] Infinite ground plane Finite ground plane Center frequency [GHz] Matching circuitry WLAN FM 4G 3G Bluetooth GPS 60 GHz MIMO TRX MMIC MIMO or diversity Multi-system terminal 2G l 2G h 4G RFID UWB DVB-H Matching circuitry Antenna 1 Antenna 2 12

13 Zero-volume antenna solutions The idea is to utilize the terminal chassis or cover as a radiator by inducing current on it in a controlled manner: divided into active and inactive parts, virtually separated at a small frequency range by a current barrier structure can also have two active parts e.g. for diversity or MIMO final goal: individually controlled current patches on the chassis to modify the surface current distribution active regions 13

14 Propagation research and antenna evaluation Propagation measurements and model development Propagation measurements and analysis of existing data at GHz Simplifed generic stochastic models, support of deterministic modelling Evaluation of antenna and radio systems with propagation data MIMO, diversity, multiuser cases 14

15 Communications and statistical signal processing Cognitive Radios and Radars Agile use of spectrum: finding and exploiting opportunities Spectrum sensing Spatial diversity; Cooperative detection Intelligent adaptation of transmit parameters, beampatterns and waveforms SU cooperation in exploiting spectral opportunity Cognitive radar learning from environment and scattering targets Signal intelligence Beampattern and waveform adaptation based on feedback Time T I M E P4 ρ=64 Frequency Time P2 N=8 Frequency Frequency 15

16 Multiantenna (MIMO) and multicarrier systems Multi-user MIMO mobile communication systems 3G LTE, 4G, WiMAX Trading-off diversity and rate Opportunistic use of radio resources and degrees of freedom MIMO techniques for small arrays in handheld terminals MIMO broadcast techniques System level performance MIMO radars Spatio-Temporal Processing Source: Slide by Alex Haimovich and Rick Blum u () t u2( t) u () t u4( t)

17 Antenna array fundamentals MIMO Propagation Parameter Estimation: diffuse and concentrated components, angular, frequency, time and polarimetric parameters (BPA IEEE PIMRC 2005) Capturing dynamic behavior of MIMO channels BSPA EUSIPCO GHz, 60 GHz propagation measurements and data analysis Antenna array signal processing for mobile terminals optimal techniques for arbitrary configurations, dealing with array imperfections Multitarget MIMO Radar tracking Optimal and low-complexity methods for space-time arrays and broadband beamforming τ 2 x z θ 1 φ 1 τ 1 y 17

18 Opportunistic and Cooperative communications Nodes located close together transmit or receive cooperatively Relay and mesh networks Opportunistic approach: find links where interference is weak and radio channel is strong exploit the dynamical effects balance overhead Wireless internet technologies 3GPP Release'9 18

19 Electronic circuit design Technology Trends in IC Design CMOS (scaling) Combination of MEMS/BAW structures to RF blocks Dense logic Analog properties degrading High f T MMIC applications Costs of passives increases Low supply voltages On same IC or same package 19

20 Small, cheap and autonomous sensor elements: Integrated, power-independent, no wires CO2 EM radiation, light, vibration... Autonomous Microsensors Low-voltage, ultra-low low power sensor chip Energy Harvesting Temperature Sensor element Sensor interface Radio interface Pressure Radio links Courtesy VTI Technologies Oy, Vantaa, Finland Motion Base station LAN 20

21 Millimetre Wave Circuit Design using CMOS 250 Why CMOS? Mass production & cost reduction Compatible with digital circuit blocks Frequency [GHz] ft [GHz] fmax [GHz] Applications GHz and 24 GHz WLANs Gigabit-per-second wireless networks >1 Gb/s mm-wave access point Gate length [nm] Wireless HDMI with HDTV quality 77 GHz collision avoidance radar for a car Millimetre wave imaging Medical, industrial and security applications 21