Academic Interests
- MEMS (Microelectromechanical systems)
- RF MEMS (MEMS for Radio Frequency systems)
- Integration of MEMS and microelectronics
- CMOS - MEMS
- Design of digital systems
- Design of integrated circuits (VLSI)
- ASICs (Application Specific Integrated Circuits)
- Microelectronics
- Nanoelectronics
- Computer architecture
Teaching
Higher education and employment history
Higher education
- Cand real, Physics (Electronics), Univ of Oslo, 1973
- Diploma in Pedagogics, Univ of Oslo, 1974
- Project Manager Seminar, NTNF, 1983
- University Pedagogics, Univ of Oslo, 1987
Employment history
- 1986 - : Professor in Computer Science, Univ of Oslo (appointed, fall 1985)
- 1986 - : Professor in Computer Science, Univ of Oslo (appointed, fall 1985)
- Aug 2003 - July 2004: Sabbatical year at SINTEF MicroNanoLaboratory, Oslo
- July 1997 - June 1998, Jan 2000 - June 2003: Head of department, Dep of Informatics, UiO
- Aug 1994 - Aug 1995: Sabbatical year at Informasjonskontroll A/S, Skedsmo
- April 1991 - Dec 92: affiliated with the Research Park, Oslo (1/5)
- Nov 1988 - June 89: affiliated with the Innovation Centre, Oslo (1/5)
- Aug 1986 - Aug 88: affiliated with NDRE, Kjeller (1/5)
- 1981 - July 86: Senior Scientist, Project Manager, The Norwegian Defence Research Establishment (NDRE) / FFI, Kjeller
- Aug 1974 - 81: Research Scientist, NDRE / FFI, Kjeller
Curriculum Vitae
Honoraria
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S. Gjessing, Ø. G. Larsen, O.Søråsen and A. Sørensen, "First price in the DEC TRI/ADD program, a contest for designs using the TURBO channel",. fall 1991
Appointments
- Member of Ifi "study program board", representing I:NOR Nanoelectronics and Robotics, from 2010 -.
- Group leader of the Nanoelectronics group at the Department of Informatics, UoO, from January 2009 - .
- Leader of committee for planning a new study program in Nanoelectronics and Robotics, IFI, UiO, 2008.
- Member of the collaboration board UiO - NAROM/ARS (Nasjonalt senter for romrelatert utdanning, Andøya rakettskytefelt), 2005 - .
- Member of steering board for Applied Mathematics and Data (MoD) 2001- 2003.
- Member of the board of directors, The Norwegian Computing Center (NR), from March 2001 - 2006.
- Member of NFR working group, defining research areas for a Center of Excellence located at Fornebu, 2000 I.
- Steering board, The Faculty of Math. and Nat.Sciences, ex. officio: 2000 I - 2003 I.
- Chairman of the Department of Informatics, UiO: Jan 2000 - June 2003 (second period)..
- Member of "Nasjonalt råd for ingeniørutdanning" established by "Det norske Høgskolerådet", representing "Det norske Universitetsråd" (nov 98 - 2000).
- Member of steering committee "KTK: Kommunikasjon: Teknologi og Kultur" at the Univ. of Oslo: 1997 II, 1998 I (chairman Francis Sejersted).
- Project leader at the Univ. of Oslo of NFR project: "Strakstiltak for å bedre rekrutteringssituasjonen innen IKT-fagene", 1997 II - 1999..
- Member of UiO's advicory board for "IT Fornebu" (1997 II - 1998 I).
- Chairman of dep, The Dep of Informatics, UiO: 1997 II, 1998 I
- Vice chairman, Dep of Informatics, 1998 II - 1999 II.
- Steering board, The Faculty of Math. and Nat.Sciences, ex. officio: 1997 II, 1998 I (substitute 1998 II - 1999 II).
- Member of steering group: FORNY Østlandet, 1996, 1997, 1998, 1999 (chairman 1998, 1999)
- Faculty Board, The Faculty of Math. and Nat.Sciences, suppl. member. 1991, 1992, 1993.
- Board, Dep of Informatics: 1989, 1990, 1991, 1992, 1993 (suppl: 1994), 1995, 1996, 1997 I.
- Steering board, Dep of Informatics: 1991, 1992, 1993 (suppl: 1989, 1990, 1994, 1995, 1996, 1997 I), 1997 II -.
Cooperation
- STAR (Space Technology and Research Development Center), UoO
- SINTEF MiNaLab
- DMMS and DSB research groups at the Department of Informatics, UoO
- Carnegie Mellon University, USA
Publications
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Kaur, Sukhdeep; Halvorsen, Einar; Søråsen, Oddvar & Yeatman, Eric M.
(2015).
Characterization and Modeling of Nonlinearities in In-Plane Gap Closing Electrostatic Energy Harvester.
Journal of microelectromechanical systems.
ISSN 1057-7157.
24(6),
p. 2071–2082.
doi:
10.1109/JMEMS.2015.2470112.
Show summary
This paper investigates in detail a micro scale in-plane gap closing electrostatic energy harvester with strong nonlinearities in squeeze-film damping, electromechanical coupling, and impacts on end-stops. The device shows softening response on increasing the bias voltage and saturation behavior on impact with end-stops at high enough acceleration amplitude. We demonstrate that a lumped model can adequately describe the measured nonlinear behavior for a range of operating conditions with nonlinear fluid damping force and impact force included in the model. While modeling capacitances, a finite-element method (FEM) is used to analyze fringing field effects on the capacitance variation for gap closing electrodes. The nominal capacitance is obtained from FEM analysis, for a range of under-cut values in the fabrication process treated as a free parameter in the model. The device modeled for linear and nonlinear squeeze-film damping force highlights the importance of nonlinear damping force to understand the device behavior over the range of operating conditions. With the compliant end-stops treated as spring-dampers and with proper choice of end-stop damping-coefficient, the model successfully captures the end-stop nonlinearities for a particular operating point and reproduces the dynamic pull-in phenomena at 8 V bias, and rms acceleration 0.6 g , as observed in the experiments. Thus, the model described in this paper reproduces the subtle nonlinear effects dominating the dynamics of an in-plane gap closing electrostatic energy harvester.
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Kuppireddi, Srinivasa Reddy & Søråsen, Oddvar
(2013).
Lateral MEMS square plate resonator post-process nano gap creation method and study.
In Dascalu, Dan (Eds.),
Proceedings of the IEEE International Semiconductor Conference (CAS).
IEEE conference proceedings.
ISSN 978-1-4673-5670-1.
p. 319–322.
doi:
10.1109/SMICND.2013.6688687.
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Kuppireddi, Srinivasa Reddy & Søråsen, Oddvar
(2013).
High aspect ratio lateral electrode nano gap rectangular plate micro-resonator novel process.
In Navickas, Romualdas (Eds.),
Proceeding of the NORCHIP 2013.
IEEE conference proceedings.
ISSN 978-1-4799-1647-4.
p. 1–4.
doi:
10.1109/NORCHIP.2013.6701998.
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Kuppireddi, Srinivasa Reddy; Sayanu, Pamidighantam & Søråsen, Oddvar
(2013).
Influence of SU8 Photopolymer for Silicon RFMEMS Packaging Applications.
International Journal of Materials Science and Engineering.
ISSN 2315-4527.
1(2),
p. 79–81.
doi:
10.12720/ijmse.1.2.79-81.
Show summary
Epoxy based photopolymer–SU8 is evaluated as microwave packaging material for packaging of Radio Frequency Micro Electro Mechanical Systems (RFMEMS). Standard and Slotted Coplanar Wave guide (CPW) transmission lines are chosen as test vehicles. Transmission lines of lengths up to 10mm are formed on HRS substrates. The fabricated transmission lines are subjected to wafer level packaging. The measured S-parameter data shows a significant difference prior to and after packaging. Further, the effects due to the packaging could be model educing lumped components and the measured data are presented in this work.
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Kuppireddi, Srinivasa Reddy & Søråsen, Oddvar
(2013).
Electrostatic actuation gap reduction method and analysis for square plate resonator on SOI substrates,
2013 Symposium on Design, Test, Integration and Packaging of MEMS/MOEMS (DTIP).
IEEE conference proceedings.
ISSN 978-1-4673-4477-7.
p. 6–9.
doi:
10.1109/smicnd.2013.6688687.
Show summary
This paper describes a simple process method for obtaining submicron capacitive electrode gaps for lateral vibrating square plate resonators and the resulting advantages. A novel electrostatic actuation method is proposed to achieve submicron electrode resonator gaps below the fabrication limitation given by conventional optical lithography. The structures are built of single crystal silicon using silicon-on-insulator wafers without complex process steps. The process sequence and simulation results for submicron electrostatic gaps are reported.
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Le, Cuong Phu; Halvorsen, Einar; Søråsen, Oddvar & Yeatman, Eric M.
(2013).
Wideband excitation of an electrostatic vibration energy harvester with power-extracting end-stops.
Smart materials and structures (Print).
ISSN 0964-1726.
22(7).
doi:
10.1088/0964-1726/22/7/075020.
Show summary
An electrostatic energy harvester with two-stage transduction is investigated for enhancement of bandwidth and dynamic range. The harvester includes a primary proof mass with two main transducers and end-stops for the proof mass functioning as secondary transducers. In the small acceleration regime, the power is primarily obtained from the main transducers. In the high acceleration regime, the mass impacts the end-stops and actuates the secondary transducers, generating additional output power. The device is designed and fabricated using the SOIMUMPs process and has a total active area of 4 × 5 mm2. Under wideband acceleration at high levels, the experimental results show that the total output power increases to about twice the output power of the main transducers, while the 3 dB-bandwidth is enlarged by a factor of 6.7 compared to the linear-response bandwidth at low levels. In comparison with a reference device made with the same die dimensions, the two-stage device improves output power instead of saturating when the maximum mass displacements of both devices reach the same limit. Measurement of output power demonstrates that the device with the transducing end-stops give an efficiency of 23.6%, while this value is 14.1% for the reference device with the conventional end-stops, at an acceleration spectral density of Sa = 19.2 × 10−3 g2 Hz−1. The efficiency is improved about by 9.5% in the impact regime.
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Le, Phu Cuong; Halvorsen, Einar; Søråsen, Oddvar & Yeatman, Eric M.
(2012).
Comparison of transducing end-stops with differentstiffness in mems electrostatic energy harvesters.
In Allen, Mark G. (Eds.),
The 12th international workshop on micro and nanotechnolgy for power generation and energy conversion applications : powerMEMS 2012.
Transducers Research Foundations.
ISSN 9780974361192.
Show summary
This paper presents experiments on electrostatic energy harvesters with different designs of end-stop
transducers, giving output power improvement and bandwidth enhancement under displacement-constrained
operation. The end-stops function as additional electrostatic transducers collecting additional power from internal
impacts. We investigate the influence of end-stop stiffness on output power by comparing two devices with
different end-stop stiffness. The comparison shows that the compliant end-stops result in higher output power
than the stiff end-stops do and increase the acceleration-amplitude range where transducing end-stops are
beneficial. Compared to their linear response, the two variants enlarge the 3dB-bandwidth with factors up to 15.9
and 13.7 respectively.
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Le, Cuong Phu; Halvorsen, Einar; Søråsen, Oddvar & Yeatman, Eric M.
(2012).
Microscale electrostatic energy harvester using internal impacts.
Journal of Intelligent Materials Systems and Structures.
ISSN 1045-389X.
23(13),
p. 1409–1421.
doi:
10.1177/1045389X12436739.
Show summary
This article presents a new concept for electrostatic energy harvesting devices that increase output power under displacement limited inertial mass motion at sufficiently large acceleration amplitudes. The concept is illustrated by two demonstrated electrostatic energy harvesting prototypes in the same die dimension: a reference device with end-stops and an impact device with movable end-stops functioning as slave transducers. Both devices are analyzed and characterized in small and large excitation regimes. We found that significant additional energy from the internal impact force can be harvested by the slave transducer. The impact device gives much higher, up to a factor of 3.7, total output power than the reference device at the same high-acceleration amplitude. The bandwidth of the response to frequency sweeps is beneficially enlarged by up to a factor of 20 by the nonlinear mechanisms of the impact device.
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Ramstad, Jan Erik & Søråsen, Oddvar
(2011).
Modeling and Design of Higher Order, Multi-Mode, Multi-Port MEMS Resonators in 90 nm CMOS.
Procedia Engineering.
ISSN 1877-7058.
25,
p. 1521–1524.
doi:
10.1016/j.proeng.2011.12.376.
Show summary
Abstract
This work presents various RF mixer-filter MEMS resonators implemented directly in CMOS. Three different composite resonator designs have been made in a 90 nm CMOS process. These resonators move laterally in two different modes made possible by the flexible internal routing and stimulation of the multi-port creating these second mode mixer-filter capabilities. By utilizing post-processed self-assembly electrodes, narrow gaps between the electrodes and the resonator is achieved for increased electrostatic coupling. Based on three different resonator designs, 4th order filters are implemented by using a coupling beam connecting pairs of resonators. The higher order mechanical filters are driven differentially.
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Kaur, Sukhdeep; Halvorsen, Einar; Søråsen, Oddvar & Yeatman, Eric M.
(2010).
Numerical analysis of nonlinearities due to rigid end-stops in energy harvesters,
PowerMEMS 2010: Proceedings of The 10th International Workshop on Micro and Nanotechnology for Power Generation and Energy Conversion Applications.
Micropower generation group.
ISSN 9789073802889.
p. 367–370.
Show summary
This paper gives a numerical analysis of nonlinearities due to rigid, elastic mechanical end-stops in a vibrating energy harvester. Both an eigenvalue problem approach and time domain simulations are used. We consider two rigid end-stops limiting the motion of a proof mass. The dynamics are linear between the impacts which cause strong nonlinear behavior. Even though the output power varies little with change in acceleration amplitude, we find that there can be drastic changes in the proof mass motion with change of amplitude. In a wide range of acceleration amplitudes the phase space trajectories are very complicated and have periods much longer than the period of the vibration, some appearing chaotic. Only in a small range of amplitudes do we find simple periodic motion.
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Ramstad, Jan Erik; Kjelgård, Kristian Gjertsen; Nordbø, Bård Eirik & Søråsen, Oddvar
(2009).
RF MEMS front-end resonator, filters, varactors and a switch using CMOS-MEMS process.
In Bourouina, Tarik; Courtois, Bernard; Ghodssi, Reza; Karam, Jean Michel; Soma, Aurelio & Yang, Hsiharng (Ed.),
Design, Test, Integration and Packaging of MEMS/MOEMS 2009.
IEEE (Institute of Electrical and Electronics Engineers).
ISSN 9782355000096.
p. 170–175.
Show summary
The paper describes the design of multiple RF MEMS
front-end components that could replace off-chip units in future transceivers. The components can effectively be combined and cofabricated with CMOS circuitry. A CMOS-MEMS approach is used, which means that the microelectromechanical parts are made by multi-layer structures in a standard CMOS process. The ASIMPS procedure offered by CMP uses the CMOS processing at STMicroelectronics, and a simple post-CMOS release-etching step is performed at Carnegie Mellon University, USA. The paper presents a resonator, resonating filters, electrothermally operated varactors and an experimental switch. The components are modeled and simulated by using CoverntorWare FEM software. A test chip is currently in production.
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Dalbro, Martin; Eikeland, Erik; Veld, Aart Joakim in't; Gjessing, Stein; Lande, Tor Sverre & Riis, Håvard Kolle
[Show all 7 contributors for this article]
(2008).
Wireless Sensor Networks for Off-shore Oil and Gas Installations.
In Braem, Bart; Benveniste, Mathilde; Dini, Cosmin; Fortino, Giancarlo; Karnapke, Reinhardt; Mauri, Jaime Lloret & Monsi, M. Sohrab H. (Ed.),
Second International IEEE Conference on Sensor Technologies and Applications, 2008. SENSORCOMM '08.
IEEE (Institute of Electrical and Electronics Engineers).
ISSN 978-0-7695-3330-8.
p. 258–263.
Show summary
Underwater development and production of oil and gas needs networked sensors and actuators to monitor the production process, to either prevent or detect oil and gas leakage or to enhance the production flow and yield of the wells. Sensors used today are large and expensive, both to manufacture and to deploy sub-sea. We suggest sensor networks created by inexpensive and small wireless sensor nodes in a redundant multi-hop topology. Preliminary designs and results are shown for two such nodes using ultrasound and infrared light as wireless commutation.
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Søråsen, Oddvar & Ramstad, Jan Erik
(2008).
From MEMS devices to smart integrated systems.
Microsystem Technologies : Micro- and Nanosystems Information Storage and Processing Systems.
ISSN 0946-7076.
14(7),
p. 895–901.
doi:
10.1007/s00542-007-0523-x.
Show summary
The smart integrated systems of tomorrow would demand a combination of micromechanical components and traditional electronics. On-chip solutions will be the ultimate goal. One way of making such systems is to implement the mechanical parts in an ordinary CMOS process. This procedure has been used to design an oscillator consisting of a resonating cantilever beam and a CMOS Pierce feedback amplifier. The resonating frequency is changed if the beam is bent by external forces. The paper describes central features of this procedure and highlights the design considerations for the CMOS-MEMS oscillator. The circuit is used as an example of a “VLSI designer” way of making future integrated micromechanical and microelectronic systems on-chip. The possibility for expansion to larger systems is reviewed.
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Søråsen, Oddvar & Ramstad, Jan Erik
(2007).
From MEMS Devices to Smart Integrated Systems.
In Chakrabarty, Krishnendu; Courtois, Bernhard; Jung, Erik; Kempe, Volker & Laur, Rainer (Ed.),
Design, Test, Integration and Packaging of MEMS/MOEMS 2007.
EDA Publishing / DTIP 2007.
ISSN 978-2-35500-000-3.
p. 134–140.
Show summary
The smart integrated systems of tomorrow would demand a combination of micromechanical components and traditional electronics. On-chip solutions will be the ultimate goal. One way of making such systems is to implement the mechanical parts in an ordinary CMOS process. This procedure has been used to design an oscillator consisting of a resonating cantilever beam and a CMOS Pierce feedback amplifier. The resonating frequency is changed if the beam is bent by external forces. The paper describes central features of this procedure and highlights the design considerations for the CMOS-MEMS oscillator. The circuit is used as an example of a “VLSI designer” way of making future integrated micromechanical and microelectronic systems on-chip. The possibility for expansion to larger systems is reviewed.
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Arhaug, Ole-Petter & Søråsen, Oddvar
(2006).
Designing H-shaped Micromechanical Filters.
Journal of Physics: Conference Series (JPCS).
ISSN 1742-6588.
34.
Show summary
This paper investigates the design constraints and possibilities given when designing a micromechanical band pass filter for intermediate frequencies (e.g. 10 MHz). The class of filters are based on coupled clamped-clamped beams constituting an H-shaped structure. A primary beam can electrostatically be activated in one of its different harmonic modes, setting the filter center frequency. The motion is transferred to an accompanying beam of equal dimensions by a mechanical coupling beam. The placement or coupling points of the quarter-wavelength coupling beam which connects the vertically resonating beams is critical with respect to the bandwidth of the filters. Of special concern has been to investigate realistic dimensions allowing the filters to be processed by an actual foundry process and to find out how the choice of materials and actual dimensions would affect the performance.
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View all works in Cristin
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Kuppireddi, Srinivasa Reddy; Pamidighantam, Sayanu; Janardhana, V.; Søråsen, Oddvar; Roy, JS & Kulkarni, RG
(2012).
Evaluation of SU8 photo polymer for microwave packaging applications.
In Lande, Tor Sverre (Eds.),
Proceedings of the 30th Norchip Conference, NORCHIP12.
IEEE Press.
ISSN 978-1-4673-2222-5.
p. 1–4.
Show summary
Epoxy based photo polymer – SU8 is evaluated as microwave packaging material for packaging of Radio Frequency Micro Electro Mechanical Systmes (RFMEMS). Standard and Slotted Coplanar Waveguide transmission lines are chosen as test vehicles. Transmission lines of lengths up to 10mm are formed on ST-Cut Quartz substrates. The fabricated transmission lines are subjected to wafer level packaging. The measured S-parameter data shows a significant difference prior to and after packaging. Further, the effects due to the packaging are modeled using lumped components and the measured data are validated with simulations in Advanced Design System. The measured and simulated data agree favorably with each other, for both before and after packaging
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Le, Cuong Phu; Halvorsen, Einar; Søråsen, Oddvar & Yeatman, Eric M.
(2011).
An electrostatic energy harvester with power-extracting end stops driven by wideband vibrations.
In Cho, Young-Ho (Eds.),
Proceedings of the 11th Workshop on Micro and Nanotechnology for Power Generation and Energy Conversion Applications, PowerMEMS 2011, 15-18 November 2011, Seoul, Republic of Korea.
Cell Bench Research Center, KAIST.
ISSN 978-89-967591-0-2.
p. 122–125.
Show summary
This paper presents an electrostatic energy harvester with two-stage transduction, giving increased bandwidth and dynamic range. The harvester includes a master proof mass with the main transducer of the device and a slave transducer functioning as an end-stop for the proof mass. Both transducers are within the same device which is designed using the 25µm thickness SOIMUMPs process with a total active area of 4×5 mm2. In a small acceleration regime, the harvester behaves as an ordinary transducer with output power primarily obtained from the master. In a high acceleration regime, the master motion impacts the slave transducer and is then confined to a maximum displacement amplitude. The slave transducer is actuated by the internal impact force, generating additional output power when the master motion reaches the limit. Under wideband acceleration at high levels, the experimental results show that the total output power is increased to about twice the output power of the main transducer, while the 3dB-bandwidth is enlarged by a factor of 5.
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Kaur, Sukhdeep; Halvorsen, Einar; Søråsen, Oddvar & Yeatman, Eric M.
(2010).
Numerical Analysis of Nonlinearities due to Rigid End-stops in Energy Harvesters.
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Dalbro, Martin; Veld, Aart Joakim in't; Gjessing, Stein; Riis, Håvard Kolle; Lande, Tor Sverre & Søråsen, Oddvar
(2008).
Building a test-bed for wireless sensor networking for under-water oil and gas installations.
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Søråsen, Oddvar
(2008).
Romteknologi ved Institutt for informatikk.
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Vistnes, Kjetil E. & Søråsen, Oddvar
(2005).
Reconfigurable Address Generators for Stream-Based Computation Implemented on FPGAs.
Show summary
This paper describes the design and implementation of an address generator for stream-based computation. The unit can generate addresses by a 1, 2 or 3-dimensional mapping from a linear data string in memory. A processing unit will get the required data in a continuous stream without empty time slots, even when switching between addressing algorithms. Each algorithm is specified by a set of parameters loaded into FIFOs in background. The unit is specified by VHDL, simulated, synthesized and implemented on an FPGA of type Xilinx Virtex-II Pro. A speed of 144 MHz is obtained for generating 36 bit addresses. Ideas for expanding the flexibility of the unit is discussed.
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Høvin, Mats Erling; Wisland, Dag T & Søråsen, Oddvar
(2004).
Hjernen styrer håndprotese.
[Newspaper].
Aftenposten.
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Høvin, Mats Erling; Wisland, Dag T & Søråsen, Oddvar
(2004).
Kunstig hånd styres av hjernen.
[Newspaper].
Apollon.
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Høvin, Mats Erling; Wisland, Dag T & Søråsen, Oddvar
(2004).
Kunstig hånd styres av hjernen.
[Newspaper].
ComputerWorld.
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Høvin, Mats Erling; Wisland, Dag T & Søråsen, Oddvar
(2004).
Kunstig hand skal styrast av hjernen.
[Internet].
Magasinett.no.
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Søråsen, Oddvar; Furuberg, Liv & Johansen, Klaus Magnus
(2004).
3D Modelling of MEMS Components for Coupled Elastic - Electrostatic Characterization.
Show summary
This paper presents a method for modelling
MEMS components whereby the designer can
perform precise electrical, mechanical, and coupled
electrical and mechanical simulations. Both surface
and bulk micromachined components can be
modelled at a geometrical level by defining simplified
pseudo processes for a commercial CAD tool such as
CovertorWare. The procedure for this approach is
described with emphasis on the bulk case. A
motivating example of a simple comb-finger structure
in an accelerometer shows that this method is
required to obtain adequate precision. A long thin
bulk micromachined mirror array, which is not easily
described analytically, was modelled by using a
pseudo process and the coupled field problem of its
elastic-electrostatic behaviour has been investigated.
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Li, Shaomeng; Tørresen, Jim & Søråsen, Oddvar
(2004).
Improving a Network Security System by Reconfigurable Hardware.
Show summary
Improving network security systems by using reconfigurable
hardware is an important research field since the
speed of the Internet is increasing. In this work, we have implemented stateful TCP inspection in a Field Programmable
Gate Array (FPGA) to help alleviating a bottleneck in network
intrusion detection systems (NIDSs). Today�s software
based NIDSs (e.g. Snort) show inefficiency and even fail to
perform for the faster Internet. Implementing stateful TCP
inspection in FPGA aims at achieving an efficient, fast NIDS
in general, � Snort specifically. By dividing a TCP connection into two flows, one to the Server and another to the Client, monitoring of the TCP flow can be sped up. A TCP
flow deals not only with a single packet but also with multiple packets over the network. Reassembly of those packets is one of the main tasks that the TCP flow monitoring should accomplish. By parallelizing the tasks of reassembling TCP packets on the Server and the Client on an FPGA, the performance of stateful TCP inspection can be greatly improved. The performance obtained by this work is a throughput of 2.75 Gbps.
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Nilsen, Geir; Tørresen, Jim & Søråsen, Oddvar
(2004).
A Variable Word-Width Content Addressable Memory for Fast String Matching.
Show summary
This work deals with off-loading some time critical
parts in the process of performing intrusion detection
from software to reconfigurable hardware (FPGA).
Signatures of known attacks must typically be
compared to high speed network traffic, and string
matching becomes a bottleneck. Content Addressable
Memories (CAMs) are known to be fast string
matchers, but offer little flexibility. For that purpose a
Variable Word-Width CAM for fast string matching
has been designed and implemented in an FPGA. A
typical feature for this CAM is that the length of each
word is independent from the others, in contrast to
common CAMs where all words have the same length.
The design has been functionally tested on a
development board for a CAM of size 1822 bytes (128
words). This design processes 8 bits per clock cycle and
has a reported maximum clock speed of 100 MHz. This
gives a thoughput of 800 Mbit/s.
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Johansen, Klaus Magnus; Søråsen, Oddvar & Furuberg, Liv
(2004).
Computed Electro-Mechanical Behaviour of Long, Narrow Silicon Mirrors.
Show summary
A mirror array with seven long, narrow silicon mirrors has been manufactured in the MultiMEMS Multi-Project-Wafer process.The mirror array was designed for a bar-code reader and is more resistant to mechanical fracture and requires lower actuation voltages than a single, larger mirror. A commercially available, low-cost thin film metal print on a ceramic substrate is used for packaging and actuation. The mirrors are tilted by electrostatic forces from thin-film electrodes placed along the edges of the mirror, a vertical distance of 10 micrometers from the mirror. Coventor simulations of the coupled elastic-electrostatic behaviour of the mirrors are presented. A model process of the SensoNor manufacturing process is created and the lithographic mask layers are defined. This input creates a 3D model of the mirrors and electrodes. The combined rotation and deflection of the mirrors as a function of applied voltage is visualized and quantified. Movement of a mirror due to forces from neighbouring electrodes is also presented. The computed pull-in voltage was 127 V in good agreement with the experiments.
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Li, Shaomeng; Tørresen, Jim & Søråsen, Oddvar
(2003).
Exploiting Stateful Inspection of Network Security in Reconfigurable Hardware.
Show summary
Abstract- One of the most important areas of a network intrusion detection system (NIDS), stateful inspection, is described in this paper. We present a novel reconfigurable hardware architecture implementing TCP stateful inspection used in NIDS. This is to achieve a more efficient and
faster network intrusion detection system as todays' NIDSs show inefficiency and even fail to perform while encountering the faster Internet. The performance of the NIDS described is expected to obtain a throughput of 3.0 Gbps.
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Li, Shaomeng; Tørresen, Jim & Søråsen, Oddvar
(2003).
Exploiting Reconfigurable Hardware for Network Security.
Show summary
Abstract� One type of network security strategy is using an
Intrusion detection system (IDS). We are implementing an IDS
in FPGA-based (Field Programmable Gate Array) recofigurable
hardware. This is to achieve higher speed and more efficient performance of network security, as networks develop very fast with consequently more demanding constraints. This study provides novel hardware architectures for an IDS system which should be able to monitor networks with a speed up to 2.68 Gbps.
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Søråsen, Oddvar
(1999).
Trender og utfordringer i elektronikk system-design.
Show summary
I foredraget vil en se på typiske trekk ved teknologi-utviklingen idag,
bl.a. det økende gapet mellom kretskompleksitet og
konstruktør-produktivitet og kravet til en strukturert design-metodikk.
Innbakte systemer, Embedded Systems, med andre grensesnitt enn skjerm
og tastatur blir stadig viktigere. Slike systemer er ofte reaktive og
kan baseres på en modell med samvirkende tilstandsmaskiner (CFSMs =
Co-design Finite-State-Machines). Hver CFSM består typisk av en
kontrolldel som bestemmer transisjoner mellom tilstandene og en
kompleks datamanipulerings-funksjon. Det er ønskelig å utsette lengst
mulig i designprosessen avgjørelsen om modulene skal implementeres i hw
eller sw. Gjenbruk av ferdig utviklede og testede Intellectual
Properties (IPs) eller Virtual Components (VCs) fra ulike leverandører
vil være viktig. Disse kan være både hardware-blokker med ulik
tilpasningsmulighet og software-kode f.eks. for DSPs. Typisk kan de
komplekse funksjonene i systemet utføres av disse IP-blokkene
(MPEG-koding/dekoding, mønster-gjenkjenning etc.).
Standardiseringsarbeid for grensesnitt mellom IPs pågår, bl.a. VSI,
Virtual Socket Interface. Selv med et standard grensesnitt mellom slike
primærblokker vil det være ønskelig med et overordnet synkroniserings-
og kontroll-nivå for en mer strukturert og kosteffektiv
system-konstruksjon. Derved unngår en å måtte modifisere importerte
IP-blokker eller basere seg på ad hoc "glue" logikk for hver ny
konstruksjon. Ved Institutt for informatikk, UiO, arbeider en med en
2-nivås, intelligent infrastruktur for å lette integreringen av
heterogene IPs. Dette bygger videre på et flerårig arbeid i
multicomputerteknikk og fokuserer det mot den nevnte problemstillingen.
Foruten synkronisering og kontroll av IP-operasjoner kan det ekstra
sammenkoblingsnivået i parallell overføre og bufre data mellom de ulike
system-delene.
-
Søråsen, Oddvar
(1999).
A structured system design approach based on reusing complex building blocks.
Show summary
Abstract --- The efficiency of system design can be greatly increased
by reuse of complex modules. Such Virtual Components (VCs) or
Intellectual Properties (IPs) from multiple sources are integrated into
an application specific system. The paper discusses this approach and
introduces a secondary control level which makes system integration
more cost-effective. A chosen model of computation extends the concept
of Codesign Finite-State-Machines (CFSMs). The control parts of the
CFSMs and data exchange are done by an intelligent infrastructure,
while the complex functional parts are performed by the IPs. This
facilitates the integration process since the IPs can be used without
modification and a structured and modular approach substitutes the use
of ad hoc glue logic. Results show that the design complexity is
considerably reduced at the expense of a moderate increase in
transistor overhead.
-
Berg, Yngvar; Lande, Tor Sverre & Søråsen, Oddvar
(1991).
A simulation framework for artificial neural networks.
-
-
Berge, Hans Kristian Otnes; Aunet, Snorre; Lande, Tor Sverre & Søråsen, Oddvar
(2015).
Improvements towards Optimal Design of Reliable Subthreshold Digital CMOS with applications in Logic and Memory.
Universitetet i Oslo.
View all works in Cristin
Published
Nov. 4, 2010 2:21 PM
- Last modified
Jan. 2, 2024 2:38 PM