Homepage of Mark Oude Alink
PhD. students ( / AIO )
|Name||M.S. Oude Alink, MSc (Mark)|
|P.O. Box 217|
|7500 AE Enschede|
|Phone||+31 53 489 4831|
|Secretary||+31 53 489 2644|
|Fax||+31 53 489 1034|
A type of radio in which communication systems are aware of their environment and internal state and can make decisions about their radio operating behavior based on that information and predefined objectives.
Spectrum is the lifeblood of RF Communications. To avoid interference, radio communication is subject to regulations, which assign dedicated parts of the radio frequency spectrum to dedicated services, such as FM-radio, TV broadcasts, GSM, etc. Measurements all over the world, such as the one made in Bern by Swisscom (figure 1), show that large parts of the spectrum are not or rarely used, while other parts are overcrowded.
To better exploit the scarce available spectrum, new radio devices could monitor the locally available spectrum, and use unused or "white space", but "step aside" if traditional radio services enter the picture. This requires a smart agile radio transceiver, referred to as a Cognitive Radio (CR). The term 'cognitive' stands for awareness of the surrounding environment; in our project we limit this awareness to availability of the spectrum.
Traditional radio transreceiver circuits are narrowband in order to be robust against interfering signals in the spectrum. Because the frequency band is fixed, external (expensive) RF-filters can be used for filtering. In CR, the frequency bands are not fixed and may even vary during a single session, so a lot of flexibility is required. This flexibility may also include flexibility in modulation schemes, because of regulations by governing authorities or simply to achieve a high spectral efficiency under heavily varying channel conditions.
CR builds on top of Software Defined Radio: a hardware system that is flexible enough such that it can be controlled by software. At the same time, it must be cheap to produce, have a low power consumption to guarantee a long battery life, have a high performance to quickly respond to varying conditions and give a high throughput.
CMOS is cheap and allows both analog and digital electronics to reside on one-chip, which makes it suitable for integration in many systems, such as mobile phones. The goal of the project is to design a fully functional CR chip in CMOS (raw bits in, raw bits out). We do not focus on higher level communication, unless this is absolutely critical information for the lower network levels.
An important task of a CR is spectrum sensing: scanning the spectrum to look for unused frequency bands. With respect to the OSI-layer model, spectrum sensing is a cross-layer problem, which makes it very interesting but also very challenging. Important questions for the physical and data-link layer are:
On higher OSI-levels (which is not the main focus of this project) spectrum sensing can also be important:
This research is shared by two projects: CMOS Cognitive Radio (CMOS CR) and Ad-hoc Dynamic Radio-spectrum Exploitation via Multi-phase Radio (AD-REM). The following people are involved in the research:
BSc / MSc assignments
Students intrigued by the above problem statements can always ask for more information, but the following assignments are directly available:
Currently, the following students are working (partly) on my part of the project:
The following projects are finished:
Mark Oude Alink was born in Hengelo, the Netherlands, in 1984. He received the MSc degree in electrical engineering and the MSc degree in computer science (both with honors) from the University of Twente, the Netherlands, in November 2008, for which he received the University Thesis Prize. During his studies he worked as student-assistant for numerous courses and for five months as a trainee at BlueShift Technologies, a developer of modular wafer handling systems.
From November 2008 until the present day, he works as a Ph.D. student at the same university at the Integrated Circuit Design group headed by Bram Nauta and at the Computer Architectures for Embedded Systems group headed by Gerard Smit. His research includes system level design, modulation and digital processing of a Cognitive Radio system.
 M.S. Oude Alink, A.B.J. Kokkeler, E.A.M. Klumperink, K.C. Rovers, G.J.M. Smit and B. Nauta, "Spurious-Free Dynamic Range of a Uniform Quantizer," IEEE Trans. Circuits Syst. II, vol. 56, no. 6, pp. 434-438, June 2009.
 M.S. Oude Alink, E.A.M. Klumperink, M.C.M. Soer, A.B.J. Kokkeler, B. Nauta, "A 50MHz-to-1.5GHz Cross-Correlation CMOS Spectrum Analyzer for Cognitive Radio with 89dB SFDR in 1MHz RBW," Proc. 4th IEEE Symposium on New Frontiers in Dynamic Spectrum Access Networks (DySPAN), Singapore, April 6-9, 2010, ISBN 978-1-4244-5188-3
 M.S. Oude Alink, A.R. Smeenge, A.B.J. Kokkeler, E.A.M. Klumperink, G.J.M. Smit, B. Nauta, "Exploring the Use of Two Antennas for Crosscorrelation Spectrum Sensing," Vehicular Technology Conference, San Francisco, September 5-8, 2011
 M.S. Oude Alink, A.B.J. Kokkeler, E.A.M. Klumperink, G.J.M. Smit, B. Nauta, "Lowering the SNR-Wall for Energy Detection Using Crosscorrelation," IEEE Trans. Veh. Technol., vol. 60, no. 8, pp. 3748-3757, 2011
 M.S. Oude Alink, E.A.M. Klumperink, A.B.J. Kokkeler, M.C.M. Soer, G.J.M. Smit, B. Nauta, "A CMOS-Compatible Spectrum Analyzer for Cognitive Radio Exploiting Crosscorrelation to Improve Linearity and Noise Performance," IEEE Trans. Circuits Syst. I, vol. 59, no. 3, pp. 479-492, March 2012.
 W. Cheng, M.S. Oude Alink, A.J. Annema, G.J.M. Wienk, B. Nauta, "A Wideband IM3 Cancellation Technique for CMOS Attenuators," in Proc. IEEE Int. Solid-State Circuits Conf. - Dig. Tech. Papers, Feb 2012, pp. 78-79
 W. Cheng, M.S. Oude Alink, A.J. Annema, J.A. Croon, B. Nauta, "RF Circuit Linearity Optimization Using a General Weak Nonlinearity Model," IEEE Trans. Circuits Syst. I (accepted)
 M.S. Oude Alink, E.A.M. Klumperink, A.B.J. Kokkeler, W. Cheng, Z. Ru, A. Ghaffari, G.J.M. Wienk, B. Nauta, "A CMOS Spectrum Analyzer Frontend for Cognitive Radio Achieving +25dBm IIP3 and -169 dBm/Hz DANL," RFIC2012 (accepted)
 M.S. Oude Alink, A.B.J. Kokkeler, E.A.M. Klumperink, Z. Ru, W. Cheng, B. Nauta, "Improving Harmonic Rejection for Spectrum Sensing using Crosscorrelation," ESSCIRC2012 (accepted)
[A] M.S. Oude Alink, "Cognitive Radio," Invited talk at the 16th URSI Forum of the Benelux, May 18, 2010, Brussels, Belgium
[B] M.S. Oude Alink, "A Crosscorrelation CMOS Spectrum Analyzer with Improved SFDR for Cognitive Radio," Invited presentation on ProRISC 2010, 20th Annual Workshop on Circuits Systems and Signal Processing, November 18-19, 2010, Veldhoven, The Netherlands.
[C] M.S. Oude Alink, "Cognitive Radio Research at the University of Twente," Invited Talk at the 17th Annual Symposium on Communications and Vehicular Technology in the Benelux, November 24, 2010, University of Twente, Enschede, The Netherlands.
[D] M.S. Oude Alink, A.R. Smeenge, A.B.J. Kokkeler, E.A.M. Klumperink, G.J.M. Smit, B. Nauta, "Crosscorrelation Spectrum Sensing Exploiting Two Antennas," ICT.Open 2011, 21th Annual Workshop on Circuits Systems and Signal Processing, November 14-15, 2011, Veldhoven, The Netherlands.
[E] W. Cheng, M.S. Oude Alink, A.J. Annema, G.J.M. Wienk, B. Nauta, "A Wideband IM3 Cancellation Technique for CMOS Attenuators," RFIC and Technology Workshop, February 29, Nijmegen, The Netherlands