| 1. |
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| 2. |
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| 3. |
- Djupsjöbacka, Anders, et al.
(författare)
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Estimating Eye-opening Penalty with Aid of the Ripple Function of Fiber Bragg-gratings
- 2007
-
Ingår i: Journal of Optical Communications. ; 28, s. 91-95
-
Tidskriftsartikel (refereegranskat)abstract
- We investigate six different methods presented in litera-ture to estimate eye-opening penalty for dispersion-com-pensating fiber Bragg gratings with aid of the grating’s ripple function. The investigation is based on theoretical ripple functions as well on measurement results of three continuously chirped gratings. The gratings in question offer full wavelength coverage between 1530 nm and 1565 nm. We will show that the eye-opening penalty de-pends on the phase and frequency of the grating’s ripple function as well as to pattern length and to pulse form of the signal used. Since the estimation methods do not ac-count for these properties, their accuracy is shown to be limited.
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| 4. |
- Djupsjöbacka, Anders, et al.
(författare)
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Measured Temporal statistics of the DGD RMS-Value in Buried Optical Fibers
- 2009
-
Ingår i: IEEE Photonics Technology Letters. - 1041-1135 .- 1941-0174. ; 21:24, s. 1801-1803
-
Tidskriftsartikel (refereegranskat)abstract
- The behavior of the differential group delay (DGD)root-mean-square (rms) value is investigated for a buried G.652fiber line in a metropolitan fiber plant outside Stockholm, Sweden.This study presents measurement results from two different mea-surement periods where the same fiber and the same measurementequipment was used. In total,2800 hours of measurements wereperformed. As expected, the recorded DGD rms-value variedwith time. The measured standard deviation for the statistics ofthe DGD rms-value fits reasonably well with values presentedin literature. The fiber line, which showed a DGD rms-value of0.45 ps in average, had an extremely long time constant. Evenafter2800 hours of measurements we have not closed in on theexpected asymptotic distribution of the measured DGD rms-value
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| 5. |
- Forzati, Marco, et al.
(författare)
-
40-gb/s field transmission through 540 km ssmf using the aprz modulation format
- 2005
-
Ingår i: Optics InfoBase Conference Papers. - : Optical Society of America. - 1557527849 - 9781557527844
-
Konferensbidrag (refereegranskat)abstract
- We report the first field transmission experiment using the APRZ modulation format for 40-Gb/s transmission through 540 km SSMF, which confirms the improved nonlinear tolerance of APRZ. The optimum phase-modulation amplitude in this experiment is p/2.
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| 6. |
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| 7. |
- Forzati, Marco, et al.
(författare)
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Asynchronous Phase Modulation for the Suppression of IFWM
- 2007
-
Ingår i: IEEE transactions on intelligent transportation systems (Print). - 1524-9050 .- 1558-0016. ; 25, s. 2969-75
-
Tidskriftsartikel (refereegranskat)abstract
- Intrachannel four-wave mixing (IFWM) represents main source of impairments in fiber transmission at 40 Gb/s. A number of phase modulation techniques have been proposed to suppress the IFWM. In this paper, we study a cost-effective way of increasing the nonlinear tolerance of a 40-Gb/s wavelength division multiplexing transmission system by asynchronous phase modulation (APM). This can be achieved with one phase modulator placed after the wavelength multiplexer so that cost is shared by all channels. We show, by means of numerical simulations and laboratory experiments, that APM greatly improves the performance of ON-OFF-keying transmission.
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| 8. |
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| 9. |
- Forzati, Marco, et al.
(författare)
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Reduction of intra-channel four-wave mixing using the alternate-phase RZ modulation format
- 2002
-
Ingår i: IEEE Photonics Technology Letters. - 1041-1135 .- 1941-0174. ; 14:9
-
Tidskriftsartikel (refereegranskat)abstract
- —The authors propose a modulation format in which the phase of the signal pulses alternates, in order to reduce the intrachannel four-wave mixing. They demonstrate numerically that the performance of a 40-Gb/s transmission link can be substantially improved.
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| 10. |
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| 11. |
- Mårtensson, Jonas, et al.
(författare)
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Improvement of Nonlinear Tolerance in 40 Gbit/s Transmission by Phase Modulation at 10 GHz
- 2002
-
Ingår i: 2002 28TH European Conference on Optical Communication. - 8790974638
-
Konferensbidrag (refereegranskat)abstract
- We propose to suppress intra-channel four-wave-mixing (IFWM) in 40 Gbit/s optical transmission by applying a phase modulation at 10 GHz. Both numerical simulations and experiments show that the penalty induced by IFWM is significantly reduced
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| 12. |
- Mårtensson, Jonas, et al.
(författare)
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Phase Modulation Schemes for Improving Intra-Channel Nonlinear Tolerance in 40 Gbit/s Transmission
- 2003
-
Ingår i: Conference on Optical Fiber Communication, Technical Digest Series. - : Institute of Electrical and Electronics Engineers Inc.. ; , s. 662-663
-
Konferensbidrag (refereegranskat)abstract
- Several schemes for suppressing infra-channel non-linearities by introducing phase shifts between pulses are compared. Simulations and experiments show that sinusoidal phase modulation at 10 GHz provides a simple and effective means for improving the nonlinear tolerance in 40 Gbit/s transmission.
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| 13. |
- Mårtensson, Jonas, et al.
(författare)
-
Suppression of intra-channel four-wave mixing by phase modulation at one quarter of bit rate
- 2002
-
Ingår i: Electronic Letters. - : Institution of Engineering and Technology (IET). - 0013-5194. ; 38:23, s. 1463-65
-
Tidskriftsartikel (refereegranskat)abstract
- A proposed improvement of the nonlinear tolerance in 40 Gbit/s optical transmission by applying a 10 GHz phase modulation is presented. The improvement is obtained because intra-channel four-wave mixing (IFWM) is suppressed. It is shown, both by numerical simulations and experiments, that the penalty induced by IFWM is significantly reduced.
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| 14. |
- Roelens, M. A. F., et al.
(författare)
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High quality pulse and device characterisation using EAM-based frequency resolved optical gating
- 2005
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Ingår i: IET Conference Publications. - : Institution of Engineering and Technology. ; , s. 397-398
-
Konferensbidrag (refereegranskat)abstract
- We report on the versatility of frequency resolved optical gating using an electro-absorption modulator to accurately characterise the pulse shape and phase of high speed telecommunication pulses, as well as properties of optical components.
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| 15. |
- Roelens, M. A. F., et al.
(författare)
-
Linear frequency resolved optical gating as a line monitoring tool
- 2006
-
Ingår i: 2006 Optical Fiber Communication Conference, and the 2006 National Fiber Optic Engineers Conference. - : IEEE Computer Society. - 1557528039 - 9781557528032
-
Konferensbidrag (refereegranskat)abstract
- We demonstrate the use of spectrograms for pulse monitoring. The technique can characterize the phase and intensity of data modulated pulses after transmission over a fiber span including a tunable dispersion compensating grating. © 2006 Optical Society of America.
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| 16. |
- Öhman, F., et al.
(författare)
-
Measurements and simulations of nonlinear noise redistribution in an SOA
- 2005
-
Ingår i: IEEE Photonics Technology Letters. - 1041-1135 .- 1941-0174. ; 17:1, s. 16-18
-
Tidskriftsartikel (refereegranskat)abstract
- Measurements and numerical simulations of the noise statistics after a semiconductor optical amplifier (SOA) demonstrate nonlinear noise redistribution. The redistribution, which relies on self-modulation due to gain saturation and carrier dynamics, shows a strong power and bandwidth dependence and can be important for SOA-based regenerators. © 2005 IEEE.
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| 17. |
- Öhman, F., et al.
(författare)
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Measurements of non-linear noise re-distribution in an SOA
- 2004
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Ingår i: Conference on Lasers and Electro-Optics, 2004. (CLEO)..
-
Konferensbidrag (refereegranskat)abstract
- Measurements of the noise statistics after a semiconductor optical amplifier (SOA) demonstrate non-linear noise re-distribution with a strong power and bandwidth dependence.
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| 18. |
- Andersson, L. I., et al.
(författare)
-
10 Gb/s Optical Transmission using a Silicon Bipolar Chipset
- 1995
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Ingår i: IEEE/LEOS 1995 Digest of the LEOS Summer Topical Meetings. Flat Panel Display Technology. ; , s. 59-60
-
Konferensbidrag (refereegranskat)abstract
- A 10 Gb/s silicon chip set including a 8:1 MUX, a 1.8 DMUX, a dynamic divider, and circuits for clock recovery is described. Results from optical transmission experiments utilizing dispersion compensation techniques such as prechirp and MSSI, and bridging distances from 50 to 100 km, will be presented.
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| 19. |
- Benedetto, S., et al.
(författare)
-
Multilevel polarization modulation using a specifically designed LiNbO/sub 3/ device
- 1994
-
Ingår i: IEEE Photonics Technology Letters. - : Institute of Electrical and Electronics Engineers (IEEE). - 1041-1135 .- 1941-0174. ; 6:8, s. 949-951
-
Tidskriftsartikel (refereegranskat)abstract
- Binary and multilevel optical polarization modulation (POLSK) is an innovative transmission technique, suitable for both coherent and direct detection. To prove its feasibility, we have built a flexible polarization modulator based on a specifically designed LiNbO/sub 3/ device. We show that it can generate any state of polarization and therefore it is suitable for transmission of any binary or multilevel POLSK constellation. Once electrically equalized, the modulator has a 4 GHz bandwidth. To test the modulator with actual digital modulation, we set up a coherent binary experiment at 800 Mbit/s, and attained a sensitivity 1.5 dB away from the noise limit of the receiver.
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| 20. |
- Borg, Tina, 1982-, et al.
(författare)
-
Perceived muscular tension in healthy subjects : a cross-sectional study
- 2016
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Ingår i: PREMUS2016. - 9780969972679 ; , s. 411-411
-
Konferensbidrag (refereegranskat)abstract
- Background. Perceived muscular tension (PMT) has been suggested to predict development of neck/shoulder pain. It has been hypothesized to be an early sign of musculoskeletal disorder and a possible mediator of stress on symptoms. However, the content of the concept of PMT is not clear. This study examined the association between PMT and physical and psychosocial factors and physical activity in a group of healthy students.Methods. This cross-sectional study was conducted on the baseline measurements of an ongoing longitudinal case-control study. A total of 63 healthy university students without complaints of neck/shoulder pain were included (21 males, 42 females, mean age 24 years). PMT was measured by asking the question “Have you, during the past month, experienced muscular tension (for example, wrinkled your forehead, ground your teeth, raised your shoulders)?” with the following response options: never, a few times, a few times per week, or one or several times per day. Self-reports on symptoms in the neck, anxiety, depression, stress, mental health, physical health, sleep and physical activity were collected with questionnaires, as well as by tenderness on palpation of neck muscles and trapezius pressure pain threshold. This produced a total of 15 variables. The relationship between these variables and PMT were analyzed using Spearman’s rank correlation coefficient.Results. Positive correlations were found between PMT and temporomandibular complaints (rho= .34, p < .001), neck crepitus (rho= .33, p < .001), anxiety (rho= .33, p < .001), depression (rho= .31, p < .05), tenderness on palpation (rho= .25, p < .05). There was a negative correlation between PMT and mental health (rho= -.26, p < .05). Frequent experience of PMT had weak to moderate correlations with frequency of symptoms and higher psychosocial strain, but not with stress. This suggests some covariance between PMT and both physical and psychosocial factors.
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| 21. |
- Brunnström, Kjell, 1960-, et al.
(författare)
-
Objective video quality assessment methods for Video assistant refereeing (VAR) Systems
- 2021
-
Rapport (övrigt vetenskapligt/konstnärligt)abstract
- This report describes the work and conclusions drawn after phase 4 in the project “Assessment methods for Video assistant refereeing (VAR) System”.The performance of six different video quality models have been evaluated, that were identified during phase 1, against the subjective video quality database that was created during phase 3. The results are slightly different for 1080p compared to 1080i. For 1080p the models VQM_VFD, SSIM and VMAF performs the best with Pearson Correlation Coefficients (PCC) above 0.9. For 1080i the PCC drops a bit overall and then VMAF and VQM_VFD are close in performance and performing the best. The overall performance for both formats VMAF an VQM_VFD stands out as the best models. In this comparison VQM_VFD has the added advantage to also be able to perform its own registration i.e. to fix any misalignment between the reference video and the distorted one.
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| 22. |
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| 23. |
- Brunnström, Kjell, 1960-, et al.
(författare)
-
Quality measurement methods for video assisting refereeing systems
- 2023
-
Ingår i: Sports Engineering. - : Springer Science and Business Media Deutschland GmbH. - 1369-7072 .- 1460-2687. ; 26:1
-
Tidskriftsartikel (refereegranskat)abstract
- Changes in the footballing world’s approach to technology and innovation, along with major advancements in broadcasting contributed to the decision by the International Football Association Board to introduce Video Assistant Referees in 2018. The change meant that under strict protocols referees could use video replays to review decisions in the event of a “clear and obvious error” or a “serious missed incident”. At the time of writing 48-Member Associations have introduced the Video Assistant Referees protocol in at least one of their tournaments and there are many technology providers who work with organisers to implement the Video Assistant Referees systems. To ensure that the use of Video Assistant Referees has a positive effect on the game, Fédération Internationale de Football Association collaborated with the RISE Research Institutes of Sweden to develop objective test methods that could be used to ensure that a system can provide an adequate solution. Each provider must be able to pass requirements that ensure that they can deal with the challenges of processing, coding, decoding, synchronising, and re-formatting of the broadcast feeds. This article will describe the development of the test methods and illustrate some initial results from a test event on Video Assistant Referees system candidates. The methods have shown to be robust and appropriate for their intended purpose and will be developed over the years to ensure the quality of Video Assistant Referees. The developed measurement methods are general and can be applied to other broadcast and video systems as well as to other sports. © 2023, The Author(s).
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| 24. |
- Brunnström, Kjell, 1960-, et al.
(författare)
-
Recommended precautions because of Covid-19 for perceptual, behavioural,quality and user experience experimentswith test persons in indoor labs
- 2020
-
Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Based on the recommendations from the Public Health Agency of Sweden(Folkhälsomyndigheten; FHM) and a set of internal rules from RISE, the followingrules are published for how to conduct experiments involving test persons in the timesof the pandemic Covid-19. The recommendations are for non-invasive and non-medicaltests, e.g. perceptual, consumer, ergonomic and human-computer interaction teststaking place in an indoor laboratory.Specifically, in this document we are specifying how experiments with test personstargeting audio and visual presentations should be done considering necessaryprecautions imposed by the Covid-19 pandemic. Laboratory experiments with testpersons, as it involves inviting people to the lab, require particular planning and carefulconsideration, if they are to be carried out safely because of the risks imposed by theCovid-19 pandemic. The safety aspects are valid for both the invited test persons andare equally important for the health of the test leaders.
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| 25. |
- Brunnström, Kjell, 1960-, et al.
(författare)
-
Video expert assessment of high quality video for Video Assistant Referee (VAR) : A comparative study
- 2024
-
Ingår i: Multimedia tools and applications. - : Springer Nature. - 1380-7501 .- 1573-7721. ; 83:20, s. 58783-58825
-
Tidskriftsartikel (refereegranskat)abstract
- The International Football Association Board decided to introduce Video Assistant Referee (VAR) in 2018. This led to the need to develop methods for quality control of the VAR-systems. This article focuses on the important aspect to evaluate the video quality. Video Quality assessment has matured in the sense that there are standardized, commercial products and established open-source solutions to measure it with objective methods. Previous research has primarily focused on the end-user quality assessment. How to assess the video in the contribution phase of the chain is less studied. The novelties of this study are two-fold: 1) The user study is specifically targeting video experts i.e., to assess the perceived quality of video professionals working with video production. 2) Six video quality models have been independently benchmarked against the user data and evaluated to show which of the models could provide the best predictions of perceived quality. The independent evaluation is important to get unbiased results as shown by the Video Quality Experts Group. An experiment was performed involving 25 video experts in which they rated the perceived quality. The video formats tested were High-Definition TV both progressive and interlaced as well as a quarters size format that was scaled down half the size in both width and height. The videos were encoded with both H.264 and Motion JPEG for the full size but only H.264 for the quarter size. Bitrates ranged from 80 Mbit/s down to 10 Mbit/s. We could see that for H.264 that the quality was overall very good but dropped somewhat for 10 Mbit/s. For Motion JPEG the quality dropped over the whole range. For the interlaced format the degradation that was based on a simple deinterlacing method did receive overall low ratings. For the quarter size three different scaling algorithms were evaluated. Lanczos performed the best and Bilinear the worst. The performance of six different video quality models were evaluated for 1080p and 1080i. The Video Quality Metric for Variable Frame Delay had the best performance for both formats, followed by Video Multimethod Assessment Fusion method and the Video Quality Metric General model.
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| 26. |
- Brunnström, Kjell, 1960-, et al.
(författare)
-
Video quality based on a user study with video professionals for Video Assisted Refereeing (VAR) Systems
- 2021
-
Rapport (övrigt vetenskapligt/konstnärligt)abstract
- This document describes a user experiment with the purpose of finding a baseline quality that is suitable for system and a database for training and evaluating the objective quality measurement methods suitable for assessing the video quality of VAR systems. A user experiment was performed involving 25 Swedish video experts. Three different video formats were incorporated 1080p, 1080i and 540i. The degradations were in most cased done using encoding with Motion JPEG (MJPEG) and H.264 in the bitrate range from 80 Mbit/s down to 10 Mbit/s. MJPEG loses quality very fast and already at 80 Mbit/s it has significantly lower quality than the uncompressed reference and then for even lower bitrates the quality falls quickly to bad. On the other hand, H.264 was not found to be significant different from the uncompressed reference until the bitrate had dropped to 10 Mbit/s for 1080p. For 1080i 20 Mbit/s was also weakly and for 540i 20 Mbit/s was significantly lower for some of the scaling methods. For 1080i the deinterlacing requires careful consideration, since the deinterlacing scheme introduced received very low quality scores. For the scaling scheme lanczos was the best and bilinear the worst. Requirement levels on bitrate and the encoders MJPEG and H.264 based on this experiment• MJPEG require more than 120 Mbit/s• H.264 require more than 50 Mbit/s
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| 27. |
- Brunnström, Kjell, 1960-, et al.
(författare)
-
Video quality of video professionals for Video Assisted Referee (VAR)
- 2023
-
Ingår i: IS and T International Symposium on Electronic Imaging Science and Technology. - : Society for Imaging Science and Technology. - 2470-1173. ; 35:10
-
Tidskriftsartikel (refereegranskat)abstract
- Changes in the footballing world’s approach to technology and innovation contributed to the decision by the International Football Association Board to introduce Video Assistant Referees (VAR). The change meant that under strict protocols referees could use video replays to review decisions in the event of a "clear and obvious error" or a "serious missed incident". This led to the need by Fédération Internationale de Football Association (FIFA) to develop methods for quality control of the VAR-systems, which was done in collaboration with RISE Research Institutes of Sweden AB. One of the important aspects is the video quality. The novelty of this study is that it has performed a user study specifically targeting video experts i.e., to measure the perceived quality of video professionals working with video production as their main occupation. An experiment was performed involving 25 video experts. In addition, six video quality models have been benchmarked against the user data and evaluated to show which of the models could provide the best predictions of perceived quality for this application. Video Quality Metric for variable frame delay (VQM_VFD) had the best performance for both formats, followed by Video Multimethod Assessment Fusion (VMAF) and VQM General model.
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| 28. |
- Chacinski, Marek, et al.
(författare)
-
400km transmission of STM-16 data on baseband and DVBT on 40GHz subcarrier
- 2008
-
Ingår i: 2008 International Conference on Telecommunications. - NEW YORK : IEEE. - 9781424420353 ; , s. 1-3
-
Konferensbidrag (refereegranskat)abstract
- A 400 km standard single mode fiber (SSMF) link with a single light-intensity modulator was upgraded for simultaneous transmission of STM-16 2.5 Gbps baseband data and digital-video-broadcast-terrestrial DVBT utilizing a 40 GHz subcarrier. An optical circulator and narrowband fiber Bragg gratings (FBG) were used to separate the signals in the optical domain and allow for simple direct baseband detection of both.
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| 29. |
- Chacinski, Marek, et al.
(författare)
-
Extension of 40 Gbps link with a directly detected 2.5 Gbps subcarrier channel
- 2009
-
Ingår i: 2009 11th International Conference on Transparent Optical Networks. - NEW YORK : IEEE. ; , s. 204-207
-
Konferensbidrag (refereegranskat)abstract
- Simultaneous transmission was achieved of 40 Gbps at baseband and 2.5 Gbps modulation on a 50 GHz subcarrier utilizing a single 40 Gbps light-intensity modulator. A novel reception method based on optically separated baseband and single sideband channel permits direct detection of both signals with use of bandwidth limited photodiodes and dispersion tolerant transmission. This method can be used to increase the total capacity of an original 40 Gbps optical link to also carry a secondary signal.
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| 30. |
- Djupsjöbacka, Anders
(författare)
-
A linearization concept for integrated-optic modulators
- 1992
-
Ingår i: IEEE Photonics Technology Letters. - : Institute of Electrical and Electronics Engineers (IEEE). - 1041-1135 .- 1941-0174. ; 4:8, s. 869-872
-
Tidskriftsartikel (refereegranskat)abstract
- A novel linearization concept to reduce the distortion products from integrated-optic modulators is proposed and analyzed. The proposed linearization concept could be used on any type of modulator with an odd transfer function. A dual parallel Mach-Zehnder modulator was linearized, and the results are compared to those obtained using a conventional linearization concept. The proposed concept gives a 40% higher modulation index compared to a concept based on reduction of the cubic nonlinearity of the modulator
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| 31. |
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| 32. |
- Djupsjöbacka, Anders, et al.
(författare)
-
Dispersion compensation by differential time delay
- 1994
-
Ingår i: Journal of Lightwave Technology. - : Institute of Electrical and Electronics Engineers (IEEE). - 0733-8724 .- 1558-2213. ; 12:10, s. 1849-1853
-
Tidskriftsartikel (refereegranskat)abstract
- A technique for optical pre- or postdistortion in order to compensate for fiber dispersion is discussed theoretically, The dispersion compensation device is based on differential time delay for the upper and the lower sideband of the modulated signal. The proposed scheme is primarily intended for high bit rate (>10 Gbit/s) time division multiplexed transmission, and in an ideal case the transmitting distance could be enhanced by a factor of 4 in a dispersive limited system. With more realistic demands on the dispersion compensation device, the gained distance is in the order of 2.5.
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| 33. |
- Djupsjöbacka, Anders, et al.
(författare)
-
Dynamic stimulated Brillouin scattering analysis
- 2000
-
Ingår i: IEEE transactions on intelligent transportation systems (Print). - 1524-9050 .- 1558-0016. ; 18, s. 416-
-
Tidskriftsartikel (refereegranskat)
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| 34. |
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| 35. |
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| 36. |
- Djupsjöbacka, Anders
(författare)
-
Prechirped duobinary modulation
- 1998
-
Ingår i: IEEE Photonics Technology Letters. - : Institute of Electrical and Electronics Engineers (IEEE). - 1041-1135 .- 1941-0174. ; 10:8, s. 1159-1161
-
Tidskriftsartikel (refereegranskat)abstract
- The proposed modulation scheme enables us to combine the advantages of the duobinary modulation, i.e., reduced transmission bandwidth compared to traditional intensity modulation, together with the advantages of prechirped modulation. Below, a theoretical investigation is presented where four different methods of modulating a double electrode Mach-Zehnder modulator is compared. It will be shown that the proposed prechirped duobinary modulation scheme will have the best performance in terms of power penalty.
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| 37. |
- Djupsjöbacka, Anders
(författare)
-
Residual chirp in integrated-optic modulators
- 1992
-
Ingår i: IEEE Photonics Technology Letters. - : Institute of Electrical and Electronics Engineers (IEEE). - 1041-1135 .- 1941-0174. ; 4:1, s. 41-43
-
Tidskriftsartikel (refereegranskat)abstract
- The authors have analyzed and measured the dispersion effects of residual chirp arising from asymmetry in field overlap in Mach-Zehnder structures. A clear influence of chirp was seen at 7 Gb/s and a propagation length of 75-km nondispersion shifted fiber at lambda =1.55 mu m. It is shown that a MZ-modulator with field overlap in one arm only and operated in the blue-shift mode is the best choice for single coplanar stripline (CPS) electrode MZ-modulators in this case. Calculations have shown good agreement with measured results. This indicates that a simple model for fiber mode propagation have shown good agreement with measured results. This can be used together with a FFT-algorithm for calculating the effect of residual chirp from external modulators in multigigabit dispersive fiber-optic systems.
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| 38. |
- Djupsjöbacka, Anders
(författare)
-
Time division multiplexing using optical switches
- 1988
-
Ingår i: IEEE Journal on Selected Areas in Communications. - : Institute of Electrical and Electronics Engineers (IEEE). - 0733-8716 .- 1558-0008. ; 6:7, s. 1227-1231
-
Tidskriftsartikel (refereegranskat)abstract
- Design considerations are considered for optical time-division multiplexing in terms of bandwidth requirements for the modulators and switches for a particular multiplexing scheme and the corresponding drive signals are derived using a time-domain approach. It is shown that these requirements are stricter than expected from simple considerations. Different types of multiplexing schemes are analyzed and are shown to behave differently due to varying chirping properties; this chirping is also calculated. A comparison to nonmultiplexed systems is made
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| 39. |
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| 40. |
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| 41. |
- Fonjallaz, P., et al.
(författare)
-
BER Assessment of Direct Optical Passband Filter for 24 GHz Millimetre-Wave Signals
- 2005
-
Ingår i: 2005 International Topical Meeting on Microwave Photonics. ; , s. 225-228
-
Konferensbidrag (refereegranskat)abstract
- Bit Error Rate measurements are performed on a 155 MB/s signal modulating a 24 GHz microwave carrier after filtering using a superimposed fibre Bragg grating for assessment of the performance of such an all-optical filter. This passband filter has a 2 GHz 3-dB bandwidth, steep flanks and a low insertion loss. The extinction ratio is better than 15 dB. The filtering of an interference signal is demonstrated as a function of frequency. Transmission through 25 km standard fibre is shown to not have significant effect on the quality of the signal after filtering.
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| 42. |
- Göreke, Hande D., et al.
(författare)
-
Perceptual Judgments of Simulated Low Temperatures in LCD based Vehicle Displays
- 2023
-
Ingår i: <em>Digest of Technical Papers - SID International Symposium</em>. - : Wiley. ; , s. 595-598
-
Konferensbidrag (refereegranskat)abstract
- A well-known drawback with LCD-displays in cold is a slow pixel response leading to poor picture quality. Low temperatures can constitute a hazard in viewing important displays in cars. Perceptual experiments with 20 test-persons were conducted to find clear and acceptable ranges on screens simulating distortions in low temperatures. The results showed perception over clear and acceptable image quality was impaired beyond -20°C for the LCD-screen in the experiments.
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| 43. |
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| 44. |
- Hermann, David, et al.
(författare)
-
Display panel certification system for the vehicle industry
- 2017
-
Ingår i: Digest of Technical Papers - SID International Symposium. - : Wiley. - 0097-966X. ; , s. 471-474
-
Konferensbidrag (refereegranskat)abstract
- The ever-increasing need for displaying in-vehicle visual information in a non-distracting way requires a high visual performance of automotive displays. For their procurement, deep technical and supply-chain knowledge is required. Therefore, based on our comparisons of in-vehicle and laboratory visual-performance measurements, we propose a certification system for automotive display panels.
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| 45. |
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| 46. |
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| 47. |
- Lindstrom, B., et al.
(författare)
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Combined multimode and singlemode fiber
- 2002
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Ingår i: Optical Fiber Communication Conference and Exhibit. ; , s. 628-629
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Konferensbidrag (refereegranskat)abstract
- A future proof combined MM- and SM-fiber is presented, which combines the advantages of both fiber types and makes upgrading and downgrading cheap and simple.
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| 48. |
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| 49. |
- Niburg, M., et al.
(författare)
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A complete sub-system of parallel optical interconnects for telecom applications
- 1996
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Ingår i: 1996 Proceedings 46th Electronic Components and Technology Conference. ; , s. 259-263
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Konferensbidrag (refereegranskat)abstract
- Increased throughput and flexibility requirements in large-scale electronic equipment create needs for increased interconnection density capacity and re-configurability. The growing demand for new broadband interactive telecom and computer services is expected to enforce this development, which presents a challenge to traditional electronic interconnection techniques and an opportunity for new optical solutions, provided that the cost of introduction of the optical technology is affordable for both system operators and service users. The authors describe a complete sub-system of parallel optical interconnects (i.e., a total solution including the link itself and the equipment practice supporting the link) which exhibits both cost and performance benefits compared to a pure electrical or a serial optical solution.
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| 50. |
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