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  • 301. Engelke, Ulrich
    et al.
    Zepernick, Hans-Jürgen
    Multiobjective Optimization of Multiple Scale Visual Quality Processing2008Konferensbidrag (Refereegranskat)
    Abstract [en]

    In this paper, multiobjective optimization is applied to determine the optimal feature weights for a multi-resolution image quality metric. The optimization is conducted with respect to two aims; maximization of quality prediction accuracy and generalisation ability to unknown images. A thresholding of the optimal weights is applied to further reduce computational complexity of the quality metric. A detailed discussion of the tradeoff between prediction performance and complexity with respect to the threshold is provided. The metric design and evaluation is supported using mean opinion scores from subjective quality experiments that we conducted in two independent laboratories. Comparison to other state of the art quality metrics reveals the ability of the proposed metric to accurately predict subjective image quality perception.

  • 302. Engelke, Ulrich
    et al.
    Zepernick, Hans-Jürgen
    Multi-resolution Structural Degradation Metrics for Perceptual Image Quality Assessment2007Konferensbidrag (Refereegranskat)
    Abstract [en]

    In this paper, a multi-resolution analysis is proposed for image quality assessment. Structural features are extracted from each level of a pyramid decomposition that accurately represents the multiple scales of processing in the human visual system. To obtain an overall quality measure the individual level metrics are accumulated over the considered pyramid levels. Two different metric design approaches are introduced and evaluated. It turns out that one of them outperforms our previous work on single-resolution image quality assessment.

  • 303. Engelke, Ulrich
    et al.
    Zepernick, Hans-Jürgen
    Pareto Optimal Weighting of Structural Impairments for Wireless Imaging Quality Assessment2008Konferensbidrag (Refereegranskat)
    Abstract [en]

    In this paper, we consider multiobjective optimization for obtaining the feature weights associated with structural image impairments and its application to wireless imaging quality assessment. The proposed framework supports optimization with respect to finding a trade-off between metric prediction accuracy and generalization to unknown images. Evaluation of optimal trade-off solutions for two representative scenarios reveal the benefits of the proposed approach. In particular, quality prediction accuracy of an objective image metric can be strongly increased and negligible features are identified that can be discarded to save computational complexity.

  • 304. Engelke, Ulrich
    et al.
    Zepernick, Hans-Jürgen
    Perceptual-based Quality Metrics for Image and Video Services: A Survey2007Konferensbidrag (Refereegranskat)
    Abstract [en]

    The accurate prediction of quality from an end-user perspective has received increased attention with the growing demand for compression and communication of digital image and video services over wired and wireless networks. The existing quality assessment methods and metrics have a vast reach from computational and memory efficient numerical methods to highly complex models incorporating aspects of the human visual system. It is hence crucial to classify these methods in order to find the favorable approach for an intended application. In this paper a survey and classification of contemporary image and video quality metrics is therefore presented along with the favorable quality assessment methodologies. Emphasis is given to those metrics that can be related to the quality as perceived by the end-user. As such, these perceptual-based image and video quality metrics may build a bridge between the assessment of quality as experienced by the end-user and the quality of service parameters that are usually deployed to quantify service integrity.

  • 305.
    Engelke, Ulrich
    et al.
    Blekinge Tekniska Högskola, Sektionen för ingenjörsvetenskap, Avdelningen för elektroteknik.
    Zepernick, Hans-Jürgen
    Blekinge Tekniska Högskola, Sektionen för ingenjörsvetenskap, Avdelningen för elektroteknik.
    Psychophysical Assessment of Perceived Interest in Natural Images: The ROI-D Database2011Konferensbidrag (Refereegranskat)
    Abstract [en]

    We introduce a novel region-of-interest (ROI) database for natural image content, the ROI-D database. The database consists of ROI maps created from manual selections obtained in a psychophysical experiment with 20 participants. The presented stimuli were 42 photographic images taken from 3 publicly available image quality databases. In addition to the ROI selections, dominance ratings were recorded that provide further insight into the interest of the selected ROI in relation to the background. In this paper, the experiment is described, the resulting ROI database is analysed, and possible applications of the database are discussed. The ROI-D database is made freely available to the image processing research community.

  • 306.
    Engelke, Ulrich
    et al.
    Blekinge Tekniska Högskola, Sektionen för teknik, Avdelningen för telekommunikationssystem.
    Zepernick, Hans-Jürgen
    Blekinge Tekniska Högskola, Sektionen för teknik, Avdelningen för telekommunikationssystem.
    Quality Evaluation in Wireless Imaging Using Feature-Based Objective Metrics2007Konferensbidrag (Refereegranskat)
    Abstract [en]

    This paper addresses the evaluation of image quality in the context of wireless systems using feature-based objective metrics. The considered metrics comprise of a weighted combination of feature values that are used to quantify the extend by which the related artifacts are present in a processed image. In view of imaging applications in mobile radio and wireless communication systems, reduced-reference objective quality metrics are investigated for quantifying user-perceived quality. The examined feature-based objective metrics provide options for controlling the processing complexity and implementation resources required for performing the quality evaluation. Furthermore, the metrics support the scaling of overhead needed for communicating the image features over the wireless link and the accuracy for predicting the image quality.

  • 307. Engelke, Ulrich
    et al.
    Zepernick, Hans-Jürgen
    Kusuma, Tubagus Maulana
    Perceptual Evaluation of Motion JPEG2000 Quality over Wireless Channels2006Konferensbidrag (Refereegranskat)
    Abstract [en]

    In this paper, we investigate the applicability of perceptual image quality metrics for quality assessment of Motion JPEG2000 (MJ2) video streams over wireless channels. A performance evaluation of MJ2 quality for different levels of source compression and channel coding settings is provided. This reveals insights into the characteristics and suitability of the considered perceptual quality metrics for wireless video quality assessment. In particular, a reduced-reference hybrid image quality metric (HIQM) is identified as the most favorable metric with respect to supporting real-time applications. The findings obtained from the considered scenarios may also guide the design of efficient physical layer functions for wireless video systems.

  • 308. Engelke, Ulrich
    et al.
    Zepernick, Hans-Jürgen
    Kusuma, Tubagus Maulana
    Subjective Quality Assessment for Wireless Image Communication: The Wireless Imaging Quality Database2010Konferensbidrag (Refereegranskat)
    Abstract [en]

    Mean opinion scores (MOS) obtained in image quality experiments are a key component in the transition from subjective to objective measures of perceived quality. In this respect, MOS are widely used to validate objective quality prediction models. To facilitate comparison between models from different laboratories it is desirable to have publicly available image quality databases. Several databases were made available in recent years. In this paper, we introduce the Wireless Imaging Quality (WIQ) database which, unlike any of the previous databases, takes into account the complex nature of a wireless communications link. The database is thus considered as a valuable complement to the existing databases. The distortion model, the test images, and two quality experiments that we conducted are explained in this paper. A number of contemporary objective quality metrics are tested for their quality prediction performance on the database. The WIQ database including test images and MOS is made freely available to the research community.

  • 309. Engelke, Ulrich
    et al.
    Zepernick, Hans-Jürgen
    Maeder, Anthony
    Visual Fixation Patterns in Subjective Quality Assessment: The Relative Impact of Image Content and Structural Distortions2010Konferensbidrag (Refereegranskat)
    Abstract [en]

    The viewing behaviour of human observers during image quality assessment is analysed. In this respect, the relative impact of image content and structural distortions is of particular interest. Two subjective experiments were conducted as a basis for analysis; a region-of-interest (ROI) experiment and an eye tracking experiment under quality assessment task. A correlation analysis and a receiver operating characteristics analysis reveal, that quality assessment takes place mainly within the ROI, indicating a higher impact of the content as compared to the distortions. This seems to be only contradicted by very strong and localised distortions outside the ROI.

  • 310.
    Enohnyaket, John Ako
    Blekinge Tekniska Högskola, Sektionen för ingenjörsvetenskap.
    An Investigation of RF Pollution Caused by IEEE 802.15.4 Body Area Networks2013Självständigt arbete på grundnivå (kandidatexamen)Studentuppsats (Examensarbete)
    Abstract [en]

    Advancement in wireless communication technologies such as wearable sensors together with recent developments in embedded computing area is enabling the design, development and implementation of body area networks. These network developments mainly use the IEEE 802.15.4 which is aimed at low power, short range communications. The body area network is a deployment of an innovative healthcare monitoring application. However, little is known about the impact of 802.15.4 on the performance of other communication devices. Due to the constant increase in devices sharing the unlicensed 2.4GHz ISM band, interference is becoming a problem of interest to researchers. In this thesis, we experimentally investigate the Radio Frequency (RF) pollution Caused by IEEE 802.15.4 body area networks. Measurement was conducted with a shimmer2r node(transmitter) attached to the human body and the Tmote Sky sensor nodes(receivers) which are deployed on three floors of the Telecommunication Network Group (TKN) Technical University(TU) building in Berlin. The average Received Signal Strength Indicator (RSSI), Link Quality Indicator (LQI) and Packet Reception Rate (PRR) was examined as a function of transmitter to receiver distance. The best LQI was observed at 0 dBm and was consistent whereas the worst LQI was at -25 dBm. Lastly, the RF pollution metric was defined based on power levels and the percentage of nodes polluted. With a transmission power level of -15 dBm, the observed RF pollution for a co-located network was minimal while of 0 dBm, the pollution effects were relatively higher.

  • 311.
    Erdogan, Ferhat
    Blekinge Tekniska Högskola, Sektionen för teknik, Avdelningen för signalbehandling.
    Implementation and Comparison of Motion Estimation Algorithms for Video Coding2005Självständigt arbete på avancerad nivå (magisterexamen)Studentuppsats (Examensarbete)
    Abstract [en]

    In video coding, motion compensated prediction between the frames is a very efficient way for exploiting temporal correlation. Different motion estimation algorithms have been developed in order to provide efficient motion compensated prediction of scene motion between frames. In this thesis, full search, fast search, hierarchical search, sub pixel interpolation and mesh based motion estimation algorithms have been implemented. Comparisons are made both in the spatial and temporal domain, mainly in terms of Peak Signal to Noise Ratio (PSNR) and computational complexity. A video codec using lifting based wavelet transform is used for the comparisons in the temporal domain.

  • 312.
    Ericsson, Andreas
    et al.
    Blekinge Tekniska Högskola, Institutionen för signalbehandling.
    Lindgren, Malena
    Blekinge Tekniska Högskola, Institutionen för signalbehandling.
    Delay-locked Loop: an adaptive timing alignment1996Självständigt arbete på avancerad nivå (magisterexamen)Studentuppsats (Examensarbete)
    Abstract [en]

    Conventional approches to the problem of extracting a clock from the data do not automatically hold the clock in the center of the data-eye. This thesis describes a data feedback technique that adjusts the clock and significantly reduces timing uncertainty by compensating for initial ciruit misalignment, propagation delay variations and low-frequency jitter. The purpose of this thesis is to investigate the characteristics of the technique with different phase detectors by analysis, simultations and experimentally work.

  • 313. Eriksson, Håkan
    Digital block Transmission and Time-of-Flight Estimation, Receiver Design and Performance Analysis1995Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
  • 314. Eriksson, Håkan
    Modelling of Waveform Deformation and Time-of-Flight Estimation1993Licentiatavhandling, sammanläggning (Övrigt vetenskapligt)
  • 315. Eriksson, Håkan
    et al.
    Börjesson, Per Ola
    Holmer, Nils-Gunnar
    High Resolution Ultrasonic Measurement of Intra-Ocular Distances1991Konferensbidrag (Refereegranskat)
  • 316. Eriksson, Håkan
    et al.
    Börjesson, Per Ola
    Holmer, Nils-Gunnar
    Modelling of Waveform Deformation and Time-of-Flight Estimation, with application to the Ultrasonic Pulse-Echo Method1993Rapport (Övrigt vetenskapligt)
  • 317. Eriksson, Håkan
    et al.
    Börjesson, Per Ola
    Holmer, Nils-Gunnar
    Modelling of Waveform Deformation in Time-of-Flight Estimation With Application to the Ultrasonic Pulse-echo Method1992Konferensbidrag (Refereegranskat)
    Abstract [en]

    The authors address the problem of estimating the time-of-flight of ultrasonic pulse-echo signals. The shape of the received waveform is modelled by a linear combination of base signals. A method for obtaining these base signals is presented. The method presumes that the excitation signal is narrow-banded in the frequency domain.

  • 318. Eriksson, Håkan
    et al.
    Börjesson, Per Ola
    Holmer, Nils-Gunnar
    Modelling of Waveform Shape Uncertianties and Time-of-Flight Estimation, with application to the Ultrasonic Pulse-Echo Method1993Konferensbidrag (Refereegranskat)
  • 319. Eriksson, Håkan
    et al.
    Börjesson, Per Ola
    Holmer, Nils-Gunnar
    Ögondjupmätning med ultraljud1990Rapport (Övrigt vetenskapligt)
  • 320. Eriksson, Håkan
    et al.
    Ödling, Per
    Börjesson, Per Ola
    Simultaneous Time-of-Flight and Channel Estimation Using a Stochastic Channel Model1993Konferensbidrag (Refereegranskat)
  • 321. Eriksson, Håkan
    et al.
    Ödling, Per
    Börjesson, Per Ola
    Holmer, Nils-Gunnar
    A Robust Correlation Receiver for Distance Estimation1994Ingår i: IEEE Transactions on Ultrasonics, Ferroelectrics and Frequency Control, ISSN 0885-3010, E-ISSN 1525-8955, Vol. 41, nr 5, s. 596-603Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Many methods for distance estimation, such as the ultrasonic pulse-echo method, involve the estimation of a Time-of-Flight (TOF). In this paper, a signal model is developed that, apart from the TOF, accounts for an unknown, linear frequency dependent distortion as well as for additive noise. We derive a TOF estimator for this model based on the criteria of Maximum Likelihood. The resulting receiver can be seen as an extension or generalization of the well known cross-correlation, or ''matched filter'', estimator described, e.g., by Nilsson in [12]. The novel receiver is found to be more robust against unknown pulse shape distortion than the cross-correlation estimator, giving less biased TOF estimates. Also, bias versus noise sensitivity can be controlled by proper model order selection.

  • 322.
    Erman, David
    Blekinge Tekniska Högskola, Institutionen för telekommunikation och signalbehandling.
    Design and Implementation of an Acoustical Transmission Protocol2002Självständigt arbete på avancerad nivå (magisterexamen)Studentuppsats (Examensarbete)
    Abstract [en]

    The RoboCup Sony Legged Robot League is an initiative to promote robotics technologies and artificial intelligence in the form of a soccer competition between four-legged robots. The Blekinge Institute of Technology, Royal Institute of Technology, the Universities of ¨ Orebro and Ume°a, competing in the RoboCup domain as Team Sweden , have been participants in the league for three years. To improve the chances of victory in the league, a way to communicate important data between robots is desired. This thesis explores methods for implementing this communication using only the built-in hardware of the robots, i.e. one speaker and two microphones.

  • 323. Erman, Maria
    et al.
    Mohammed, Abbas
    Rakus-Andersson, Elisabeth
    Fuzzy Logic Applications in Wireless Communications2009Konferensbidrag (Refereegranskat)
    Abstract [en]

    A survey of fuzzy logic applications and principles in wireless communications is presented, with the aim of highlighting successful usage of fuzzy logic techniques in applied telecommunications and signal processing. To the best of our knowledge, this is the first such study of its kind. This paper will focus firstly on discerning prevalent fuzzy logic or fuzzy-hybrid approaches in the areas of channel estimation, channel equalization and decoding, and secondly outlining what conditions and situations for which fuzzy logic techniques are most suited for these approaches. Furthermore, after insights gained from isolating fuzzy logic techniques applied to real problems, this paper proposes areas for further research targeted to practice-oriented researchers.

  • 324.
    Evangelista, Ignacio
    et al.
    Polytechnic Institute of Rosario, ARG.
    Cadierno, Matias
    Polytechnic Institute of Rosario, ARG.
    Farina, Juan
    Polytechnic Institute of Rosario, ARG.
    Roldan, Gabriel
    Polytechnic Institute of Rosario, ARG.
    Pozzo, Maria Isabel
    National Scientific and Technical Research Council, Rosario, ARG.
    Dobboletta, Elsa
    National Scientific and Technical Research Council, Rosario, ARG.
    Garcia-Zubia, Javier
    University of Deusto, ESP.
    Hernandez, Unai
    University of Deusto, ESP.
    Marchisio, Susana
    National University of Rosario, ARG.
    Concari, Sonia
    National University of Rosario,ARG.
    Alves, Gustavo
    Instituto Politécnico do Porto, PRT.
    Nilsson, Kristian
    Blekinge Tekniska Högskola, Fakulteten för teknikvetenskaper, Institutionen för tillämpad signalbehandling.
    Active learning of DC circuits: Spreading the use of the VISIR remote lab in Argentina2018Ingår i: EDUNINE 2018 - 2nd IEEE World Engineering Education Conference: The Role of Professional Associations in Contemporaneous Engineer Careers, Proceedings, Institute of Electrical and Electronics Engineers Inc. , 2018, s. 216-221Konferensbidrag (Refereegranskat)
    Abstract [en]

    The VISIR+ Project was launched in 2015 with the objective of spreading the use of the VISIR remote laboratory in Latin America, promoting an enquiry-based approach to teaching and learning on electric and electronic circuits. Within the scope of this project, several didactical implementations were achieved both in Argentina and in Brazil. This article describes the latest implementation of VISIR in a pre-university technical school in Argentina (associated partner of the VISIR+ team) in three Physics courses with students having different background knowledge and interests. A set of activities comprising simulations, remote and hands-on experiments were designed in order to engage students in the learning process. The implementation was assessed in terms of the learning objectives and outcomes. Results showed that VISIR is an effective tool to promote active learning. Moreover, this experience seems highly valuable to encourage the dissemination of VISIR in Argentina. © 2018 IEEE.

  • 325. Fai, Cedric Yiu Ka
    et al.
    Grbic, Nedelko
    Kok-Lay, Teo
    Nordholm, Sven
    A New Design Method for Broadband Microphone Arrays for Speech Input in Automobiles2002Ingår i: IEEE Signal Processing Letters, ISSN 1070-9908, E-ISSN 1558-2361, Vol. 9, nr 7, s. 222-224Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    A new design method for broadband microphone arrays is presented. Using sequences of calibration signals, the method is able to design finite-impulse response (FIR) filters with specific performance. The method can control and adjust the speech distortion, noise suppression, and echo cancellation directly. It turns out that a significantly shorter filter length can be applied to achieve better overall performance than the least-squares method or the signal-to-noise plus interference method.

  • 326.
    Faisal, Mohammed
    Blekinge Tekniska Högskola, Sektionen för ingenjörsvetenskap.
    Development of a GB-SAR System and Perform Basic and Advance Measurements for a Fixed Target2011Självständigt arbete på avancerad nivå (masterexamen)Studentuppsats (Examensarbete)
    Abstract [en]

    Ground-Based Synthetic Aperture Radar (GB-SAR) system is a new innovative monitoring technique has been invented depending on the use of ground based applications and highly repeatable measurements. GB-SAR is a new class of SAR system based on unconventional platform like ground, building and ground vehicles that acts as a useful complement of airborne and spaceborne SAR system. In this empirical thesis project, we described a first hands-on experience working with our Ground-Based Synthetic Aperture Radar (GB-SAR). A large part of this thesis has been devoted to describe image construction process by Global Backprojection (GBP) algorithm, development of a GB-SAR system and perform two different experiments. We have developed a system full of polarimetric and interferometric functionalities to perform different measurements phenomena. The system consists of a Vector Network Analyzer (ENA 5071C), one Double Ridge Guide Horn Antenna, one Low loss-high frequency cable and an Antenna Positioner. The system can be operated in a frequency range from 300 MHz to 20 GHz, allowing a scanning aperture of 1.8 meter 1.6 meter in horizontal and vertical direction respectively. Measurements has performed in a closed door environment for two different experiments related to acquired data compression in range and image formation by GBP algorithm. The experimental results showed the excellent interferometric performance as we expected from our GB-SAR system, which should perform many useful and paramount applications for further research work at Blekinge Institute of Technology (BTH, Sweden).

  • 327.
    Faisal, Shah
    Blekinge Tekniska Högskola, Sektionen för datavetenskap och kommunikation.
    Performance Analysis of 4G Networks2010Självständigt arbete på avancerad nivå (masterexamen)Studentuppsats (Examensarbete)
    Abstract [sv]

    Mobil kommunikation utvecklas mycket snabbt med tiden, är ny teknik införs för att underlätta mobilanvändare mer av tekniken. Det förflutna teknik ersätts av nya och behov ökar för ny teknik som skall utvecklas. En sådan utveckling är fjärde generationens nät. Kallas även kommande generationen eller nästa generations nät. Införandet av 4G har räckvidden för mobil kommunikation. Nu mobil är inte bara en enhet som används för att prata, men dess mer eller mindre en bärbar dator som kan tjäna olika syften. 4G erbjuder högre dataöverföringshastigheter med sömlös roaming. Den mobila användaren kan kommunicera utan störningar samtidigt som du slår sin täckning nätverk. 4G är fortfarande passerar genom forskning och därför finns det vissa problem som behöver rättas till för att gynna användarna av den helt. I denna rapport diskuterar vi olika utmaningar 4G står inför och lösningar på dessa problem diskuteras. Vi föreslår vårt eget sätt att förbättra QoS i 4G genom kombination av mobilitet protokoll SMIP och SIP. Vi föreslår att genom att använda ett sådant system som vi kan uppnå bättre QoS under processen för överlämnandet.

  • 328.
    farooq, Muhammad
    et al.
    Blekinge Tekniska Högskola, Sektionen för ingenjörsvetenskap.
    Raja, Abdullah Aslam
    Blekinge Tekniska Högskola, Sektionen för ingenjörsvetenskap.
    Genetic Algorithm for Selecting Optimal Secondary Users to Collaborate in Spectrum sensing2010Självständigt arbete på avancerad nivå (masterexamen)Studentuppsats (Examensarbete)
    Abstract [sv]

    Cognitive Radio is an innovative technology that allows the secondary unlicensed users to share the spectrum with licensed primary users to utilize the spectrum. For maximum utilization of spectrum, in cognitive radio network spectrum sensing is an important issue. Cognitive user under extreme shadowing and channel fading can‟t sense the primary licensed user signal correctly and thus to improve the performance of spectrum sensing, collaboration between secondary unlicensed users is required. In collaborative spectrum sensing the observation of each secondary user is received by a base station acting as a central entity, where a final conclusion about the presence or absence of the primary user signal is made using a particular decision and fusion rule. Due to spatially correlated shadowing the collaborative spectrum sensing performance decreases, and thus optimum secondary users must be selected to, not only improve spectrum sensing performance but also lessen the processing overhead of the central entity. A particular situation is depicted in the project where according to some performance parameters, first those optimum secondary users that have enough spatial separation and high average received SNR are selected using Genetic Algorithm, and then collaboration among these optimum secondary users is done to evaluate the performance. The collaboration of optimal secondary user providing high probability of detection and low probability of false alarm, for sensing the spectrum is compared with the collaboration of all the available secondary users in that radio environment. At the end a conclusion has been made that collaboration of selected optimum secondary users provides better performance, then the collaboration of all the secondary users available.

  • 329.
    Farooq, Omer
    et al.
    Blekinge Tekniska Högskola, Sektionen för ingenjörsvetenskap.
    Molla, Bodiuzzaman
    Blekinge Tekniska Högskola, Sektionen för ingenjörsvetenskap.
    Observer Implementation in an FPGA Using Simulink and Xilinx System Generator2010Självständigt arbete på avancerad nivå (masterexamen)Studentuppsats (Examensarbete)
    Abstract [en]

    In order to reduce the cost of the current switched resonant power converters, a state observer is introduced to provide the controller with the required information for the effective switching of the converter without the need of expensive sensory inputs from the resonant circuit. This Master's thesis investigates the usage of Matlab/Simulink and Xilinx System Generator as an implementation tool for Field Programmable Gate Array (FPGA) development of the Observer Model. The main aim is to keep the model size to a minimum while keeping the error within a reasonable range, allowing the observer to converge.

  • 330. Fidalgo, André
    et al.
    Alves, Gustavo
    Marques, Maria A.
    Viegas, Maria C.
    Costa-Lobo, Maria C.
    Hernández, Unai
    García-Zubia, Javier
    Gustavsson, Ingvar
    Blekinge Tekniska Högskola, Sektionen för ingenjörsvetenskap, Avdelningen för elektroteknik.
    Using remote labs to serve different teacher's needs: A case study with VISIR and RemotElectLab2012Konferensbidrag (Refereegranskat)
    Abstract [en]

    Remote Laboratories are an emergent technological and pedagogical tool at all education levels, and their widespread use is an important part of their own improvement and evolution. This paper describes several issues encountered on laboratorial classes, on higher education courses, when using remote laboratories based on PXI systems, either using the VISIR system or an alternate in-house solution. Three main issues are presented and explained, all reported by teachers that gave support to students use of remote laboratories. The first issue deals with the need to allow students to select the actual place where an ammeter is to be inserted on electric circuits, even incorrectly, therefore emulating real world difficulties. The second one deals with problems with timing when several measurements are required at short intervals, as in the discharge cycle of a capacitor. And the last issue deals with the use of a multimeter in DC mode when reading AC values, a use that collides with the lab settings. All scenarios are presented and discussed including the solution found for each case. The conclusion derived from the described work is that the remote laboratories area is an expanding field, where practical use leads to improvement and evolution of the available solutions, requiring a strict cooperation and information sharing between all actors, i.e. developers, teachers and students.

  • 331.
    Fiedler, Markus
    et al.
    Blekinge Tekniska Högskola, Sektionen för teknik, Avdelningen för telekommunikationssystem.
    Zepernick, Hans-Jürgen
    Blekinge Tekniska Högskola, Sektionen för teknik, Avdelningen för telekommunikationssystem.
    Lundberg, Lars
    Blekinge Tekniska Högskola, Sektionen för teknik, Avdelningen för telekommunikationssystem.
    Arlos, Patrik
    Blekinge Tekniska Högskola, Sektionen för teknik, Avdelningen för telekommunikationssystem.
    Pettersson, Mats
    Blekinge Tekniska Högskola, Sektionen för teknik, Avdelningen för telekommunikationssystem.
    QoE-based Cross-Layer Design of Mobile Video Systems: Challenges and Concepts2009Konferensbidrag (Refereegranskat)
    Abstract [en]

    This conceptual paper focuses on revealing challenges and offering concepts associated with the incorporation of the Quality of Experience (QoE) paradigm into the design of mobile video systems. The corresponding design framework combines application, middleware and networking layer in a unique cross-layer approach, in which all layers shall jointly analyse the quality of the video and its delivery in face of volatile conditions. Particular ingredients of the framework are efficient video processing, advanced realtime scheduling, and reduced-reference metrics on application and network layer.

  • 332.
    Fontecha, Gorka Treceño
    et al.
    Blekinge Tekniska Högskola, Sektionen för teknik, Avdelningen för signalbehandling.
    Barbero., Beatriz Mora
    Blekinge Tekniska Högskola, Sektionen för teknik, Avdelningen för signalbehandling.
    Examination of Various Approaches to Possibly Improve the Existing Algorithms Applied in Fingerprint Recognition Systems2007Självständigt arbete på grundnivå (kandidatexamen)Studentuppsats (Examensarbete)
    Abstract [en]

    In human fingerprints there are plenty of small details which are the discontinuities in the ridges, denoted minutiae. Minutiae-based matching is a wellknown method applied in fingerprint recognition. Minutiae defines a representative feature vector of a fingerprint. Due to quality variations in fingerprint images a preprocessing in form of binarization and skeltonization is applied, before obtaining the feature vector. Once the features of each fingerprint are obtained, a matching algorithm carries out the comparison task between those features vectors to determine if they match. In the new binarization function, quality at the same time that speed are essential requirements. In order to sort out this subject, areas of an adaptive size are analyzed instead of a pixel by pixel examination. The binarization algorithm is implemented in the frequency domain with the concept of ridges and their orientations. Skeletonization is needed as a preprocessing step with the aim of obtaining the minutiae from the fingerprint. It is a matter of fact that the high quality skeleton is an emphatic factor in the fingerprint recognition. A robust skeletoned image will ensure a reliable extraction of features. Several strategies relating to the application of filters will be discussing in order to speed-up the iteractive thinning algorithms. The proposed minutiae matching algorithms explore though several variations of the geometric hashing method. Based on minutiae features, new approaches are presented to obtain an effectiveness function.

  • 333.
    Francisco, Manuel Ayuso de
    Blekinge Tekniska Högskola, Sektionen för ingenjörsvetenskap.
    Research on the Buck Converter’s Efficiency2013Självständigt arbete på grundnivå (kandidatexamen)Studentuppsats (Examensarbete)
    Abstract [sv]

    The Buck Converter is a voltage regulator consisted on an electronic circuit composed by a mosfet, a diode, an inductor and a capacitor. There are some implicit losses which depend on the choice of the different components. Therefore, the topic of this thesis is focused on that choice and the simulation with the components chosen shows the efficiency achieved. To simulate, it is necessary to make the mathematical analysis of the converter.

  • 334. Fundin, Per
    et al.
    Haan, Jan Mark de
    Grbic, Nedelko
    Claesson, Ingvar
    Nordholm, Sven
    Minimal Aliasing Subband System Identification2001Konferensbidrag (Refereegranskat)
    Abstract [en]

    Subband adaptive filters have been proposed to avoid the drawbacks of slow convergence and high computational complexity associated with time domain adaptive filters. While the computational complexity is reduced, other undesired properties, such as signal delays and signal aliasing, are introduced. Aliasing effects may result in loss of perception in speech applications. A method for the design of oversampled filter banks is proposed to reduce these effects. The design method aims at reducing the inband aliasing as well as the reconstruction aliasing for the reason of achieving robustness when weighting in the subbands alters the subband signal phase and magnitude.

  • 335.
    Gabriel, Karim
    et al.
    Blekinge Tekniska Högskola, Sektionen för teknik, Avdelningen för signalbehandling.
    Moudarres, Sani Al
    Blekinge Tekniska Högskola, Sektionen för teknik, Avdelningen för signalbehandling.
    The development of a Speech Level Adjustment Technique for late Deaf People2009Självständigt arbete på avancerad nivå (magisterexamen)Studentuppsats (Examensarbete)
    Abstract [en]

    People that become deaf later on in life do have the ability to speak with correct pronunciation but since they can not hear their own voice nor the noise in the enviroment, they have difficulties to adjust their voice level to the surrounding environment. In this thesis we propose and algorithm which can be used on a prototype to help the late deafened people to adjust their voice level to the surrounding.

  • 336.
    Gaddam, Purna Chandra Srinivas Kumar
    et al.
    Blekinge Tekniska Högskola, Fakulteten för teknikvetenskaper, Institutionen för tillämpad signalbehandling.
    Sunkara, Prathik
    Blekinge Tekniska Högskola, Fakulteten för teknikvetenskaper, Institutionen för tillämpad signalbehandling.
    Advanced Image Processing Using Histogram Equalization and Android Application Implementation2016Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    Now a days the conditions at which the image taken may lead to near zero visibility for the human eye. They may usually due to lack of clarity, just like effects enclosed on earth’s atmosphere which have effects upon the images due to haze, fog and other day light effects. The effects on such images may exists, so useful information taken under those scenarios should be enhanced and made clear to recognize the objects and other useful information. To deal with such issues caused by low light or through the imaging devices experience haze effect many image processing algorithms were implemented. These algorithms also provide nonlinear contrast enhancement to some extent. We took pre-existed algorithms like SMQT (Successive mean Quantization Transform), V Transform, histogram equalization algorithms to improve the visual quality of digital picture with large range scenes and with irregular lighting conditions. These algorithms were performed in two different method and tested using different image facing low light and color change and succeeded in obtaining the enhanced image. These algorithms helps in various enhancements like color, contrast and very accurate results of images with low light. Histogram equalization technique is implemented by interpreting histogram of image as probability density function. To an image cumulative distribution function is applied so that accumulated histogram values are obtained. Then the values of the pixels are changed based on their probability and spread over the histogram. From these algorithms we choose histogram equalization, MATLAB code is taken as reference and made changes to implement in API (Application Program Interface) using JAVA and confirms that the application works properly with reduction of execution time.

  • 337.
    Gagbla, George Kofi
    Blekinge Tekniska Högskola, Sektionen för teknik, Avdelningen för telekommunikationssystem.
    Applying Keystroke Dynamics for Personal Authentication2005Självständigt arbete på avancerad nivå (magisterexamen)Studentuppsats (Examensarbete)
    Abstract [en]

    With the establishment of the information society, security had become the greatest concern for Institutions transacting business over the Internet. Home banking and on-line brokerage applications currently, use basic software-only security functions for the internet such as server authentications and Secure Sockets layer. Higher levels of protections are being achieved with Smart card based authentication schemes and transaction protocols. Password based security identifies users based on what they know – the password or PIN, which can be guessed, hacked, found or stolen. Smart Cards, tokens and badges identify users based on what they have which can also be lost, loaned or stolen. The objective of the thesis was to design and implement a biometric authentication scheme by means of keystroke dynamics to secure web applications. The scheme illustrates the effect of the template size and the number of biometric features used to improve performance of FAR, FRR and EER. The enrolment process is devoid of spurious outliers that may introduce significant variations to template data. Due to the dependence of the system on the user’s psychological characteristics, the adaptation module introduces dynamism into the template features per changes in the legitimate user’s login template variants. At the quest of attaining a zero bias in statistical variants, an off-line simulator tool was designed to regenerate impostor and genuine data set obtained from live users and set as input to the system. The report includes an architectural description of the system, conceptual models and analysis of field data of over 200 samples.

  • 338.
    GAJJELA, VENKATA SARATH
    et al.
    Blekinge Tekniska Högskola, Fakulteten för teknikvetenskaper, Institutionen för tillämpad signalbehandling.
    DUPATI, SURYA DEEPTHI
    Blekinge Tekniska Högskola, Fakulteten för teknikvetenskaper, Institutionen för tillämpad signalbehandling.
    Mobile Application Development with Image Applications Using Xamarin2018Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    Image enhancement improves an image appearance by increasing dominance of some features or by decreasing ambiguity between different regions of the image. Image enhancement techniques have been widely used in many applications of image processing where the subjective quality of images is important for human interpretation. In many cases, the images have lack of clarity and have some effects on images due to fog, low light and other daylight effects exist. So, the images which have these scenarios should be enhanced and made clear to recognize the objects clearly. Histogram-based image enhancement technique is mainly based on equalizing the histogram of the image and increasing the dynamic range corresponding to the image. The Histogram equalization algorithm was performed and tested using different images facing the low light, fog images and colour contrast and succeeded in obtaining enhanced images. This technique is implemented by averaging the histogram values as the probability density function. Initially, we have worked with the MATLAB code on Histogram Equalization and made changes to implement an Application Program Interface i.e., API using Xamarin software. The mobile application developed using Xamarin software works efficiently and has less execution time when compared to the application developed in Android Studio. Debugging of the application is successfully done in both Android and IOS versions.

    The focus of this thesis is to develop a mobile application on Image enhancement using Xamarin on low light, foggy images.

  • 339.
    Garcia-Zubia, Javier
    et al.
    Univ Deusto, ESP.
    Cuadros, Jordi
    Univ Ramon Llull, ESP.
    Romero, Susana
    Univ Deusto, ESP.
    Hernandez-Jayo, Unai
    Univ Deusto, ESP.
    Orduna, Pablo
    Univ Deusto, ESP.
    Guenaga, Mariluz
    Univ Deusto, ESP.
    Gonzalez-Sabate, Lucinio
    Univ Ramon Llull, ESP.
    Gustavsson, Ingvar
    Blekinge Tekniska Högskola, Fakulteten för teknikvetenskaper, Institutionen för tillämpad signalbehandling. Blekinge Tekniska Högskola, Sektionen för ingenjörsvetenskap, Avdelningen för elektroteknik. Blekinge Tekniska Högskola, Institutionen för signalbehandling.
    Empirical Analysis of the Use of the VISIR Remote Lab in Teaching Analog Electronics2017Ingår i: IEEE Transactions on Education, ISSN 0018-9359, E-ISSN 1557-9638, Vol. 60, nr 2, s. 149-156Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Remote laboratories give students the opportunity of experimenting in STEM by using the Internet to control and measure an experimental setting. Remote laboratories are increasingly used in the classroom to complement, or substitute for, hands-on laboratories, so it is important to know its learning value. While many authors approach this question through qualitative analyses, this paper reports a replicated quantitative study that evaluates the teaching performance of one of these resources, the virtual instrument systems in reality (VISIR) remote laboratory. VISIR, described here, is the most popular remote laboratory for basic analog electronics. This paper hypothesizes that use of a remote laboratory has a positive effect on students' learning process. This report analyzes the effect of the use of VISIR in five different groups of students from two different academic years (2013-2014 and 2014-2015), with three teachers and at two educational levels. The empirical experience focuses on Ohm's Law. The results obtained are reported using a pretest and post-test design. The tests were carefully designed and analyzed, and their reliability and validity were assessed. The analysis of knowledge test question results shows that the post-test scores are higher that the pretest. The difference is significant according to Wilcoxon test (p < 0.001), and produces a Cohen effect size of 1.0. The VISIR remote laboratory's positive effect on students' learning processes indicates that remote laboratories can produce a positive effect in students' learning if an appropriate activity is used.

  • 340.
    Garre, Veeratej
    et al.
    Blekinge Tekniska Högskola, Sektionen för ingenjörsvetenskap.
    Mannem, Sailesh Kumar
    Blekinge Tekniska Högskola, Sektionen för ingenjörsvetenskap.
    An Acoustic Echo Cancellation System based on Adaptive Algorithm2012Självständigt arbete på avancerad nivå (masterexamen)Studentuppsats (Examensarbete)
    Abstract [en]

    Adaptive filtering technique is one of the core technologies in digital signal processing and finds numerous application areas in science as well as in industry. Adaptive filtering technique is widely used in many applications, including echo cancellation, adaptive noise cancellation, adaptive beam forming and adaptive equalization. Acoustic echo is a common occurrence in today’s telecommunication systems. The distraction caused by the acoustic echo, reduces the speech quality in the communication. In the communication system acoustic echo cancellers is used works as the far-end signal is delivered to the system, it will be reproduced by the loudspeaker in the room. A microphone in the room picks up the resulting direct path sound and consequent reverberant sound as a near-end signal, The far-end signal is filtered and delayed to resemble the near-end signal, filtered far-end signal is subtracted from the near-end signal. The resultant signal represents sounds present in the room excluding any direct or reverberated sound produced by the loudspeaker. The AEC with adaptive filtering technique will more accurately enhance the speech quality in hands-free and teleconferencing communication systems. The focus is on speech enhancement of speech signal with reverberated signal in handsfree speech communication using AEC with adaptive filtering technique. There are many adaptive algorithms available in the literature for echo cancellation and every algorithm have its own properties, but the aim of algorithms using for echo cancellation is to achieve higher ERLE(amount of echo cancelled) in dB at a higher rate of convergence with low complexity. The adaptive algorithms NLMS, APA and RLS for echo cancellation were successfully implemented in MATLAB. The three algorithms for AEC are tested with simulation in three different echo occurring environments by changing microphone position, source position and room dimensions. The performance evaluation of the NLMS, APA and RLS algorithms are measured with ERLE parameter. The results show that the RLS algorithm have good performance with high rate of convergence speed but the computational complexity is high which makes it impractical in real time applications. The amount of echo cancellation with APA algorithm is higher than NLMS with less computational complexity than RLS and easy to implement in real time. The amount of echo cancellation with NLMS is low when compared to RLS and APA but it is easy to implement in real time with less computational complexity. The detailed view of the comparison results of three algorithms at three different environments are shown in section 6.

  • 341.
    Gaszczyk, Dariusz
    Blekinge Tekniska Högskola, Fakulteten för teknikvetenskaper, Institutionen för tillämpad signalbehandling.
    Wearable Assistant For Monitoring Solitary People2016Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    Master Thesis presents the system consisting of software and components of Arduinoplatform along with modules compatible with it, intended for use indoor. The device fulfils thefollowing requirements which are: to ensure privacy preservation, low energy consumptionand the wireless nature.

    This thesis reports the development of a prototype that would ensure step detection,posture detection, indoor localization, tumble detection and heart rate detection using themicrocontroller, AltIMU-10 v4 module, heart rate monitor, WiFi module and battery. Veryimportant part of the thesis is algorithm, which uses comparison function. Thanks to thewireless nature of a prototype, the system collects data regardless of an environment and sendthem directly to every device supported by Microsoft Windows platform, Linux platform orOS X platform, which are monitored by the supervisor, who takes care of the solitary person.

    The main contributions of the prototype are: indoor localization, identification andclassification of occurring situations and monitoring vital signs of the solitary person.

    To ensure indoor localization the prototype must collect data from accelerometer. Ofcourse data from AltIMU-10 v4 module in basic form are useless for the supervisor, so thealgorithm, using by the prototype, is programmed to processing and filtering it.

    Algorithm is also used to identification and classification occurring situations. Datafrom accelerometer are processed by it and compared with the created pattern.

    Monitoring vital signs of the solitary person are more complicated function, because itrequires not only data from accelerometer, but also from heart rate monitor. This sensor isusing to the analyzing condition of the patient when dangerous situation occurs.

  • 342.
    Gatti, Pruthvi Venkatesh
    et al.
    Blekinge Tekniska Högskola, Fakulteten för teknikvetenskaper, Institutionen för tillämpad signalbehandling.
    Velugubantla, Krishna Teja
    Blekinge Tekniska Högskola, Fakulteten för teknikvetenskaper, Institutionen för tillämpad signalbehandling.
    Contrast Enhancement of Colour Images using Transform Based Gamma Correction and Histogram Equalization2017Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    Contrast is an important factor in any subjective evaluation of image quality. It is the difference in visual properties that makes an object distinguishable from other objects and background.

    Contrast Enhancement method is mainly used to enhance the contrast in the image by using its Histogram. Histogram is a distribution of numerical data in an image using graphical representation. Histogram Equalization is widely used in image processing to adjust the contrast in the image using histograms. Whereas Gamma Correction is often used to adjust luminance in an image.

    By combining Histogram Equalization and Gamma Correction we proposed a hybrid method, that is used to modify the histograms and enhance contrast of an image in a digital method. Our proposed method deals with the variants of histogram equalization and transformed based gamma correction. Our method is an automatically transformation technique that improves the contrast of dimmed images via the gamma correction and probability distribution of luminance pixels. The proposed method is converted into an android application.

    We succeeded in enhancing the contrast of an image by using our method and we have tested for different alpha values. Graphs of the gamma for different alpha values are plotted.

  • 343.
    Gertsovich, Irina
    et al.
    Blekinge Tekniska Högskola, Sektionen för teknik, Avdelningen för signalbehandling.
    Bartuněk, Josef Ström
    Blekinge Tekniska Högskola, Sektionen för teknik, Avdelningen för signalbehandling.
    Håkansson, Lars
    Blekinge Tekniska Högskola, Sektionen för teknik, Avdelningen för signalbehandling.
    Nilsson, Mikael
    A novel methodology for the interoperability evaluation of an iris segmentation algorithm2013Konferensbidrag (Refereegranskat)
    Abstract [en]

    The performance of an iris recognition system depends greatly on how well the iris segmentation part of the system performs its task. The performance of an iris segmentation algorithm can be evaluated using different criteria and methods. Some of the methods evaluate the performance of the segmentation algorithm based on the performance of the whole iris recognition system. Other methods evaluate the performance of an iris segmentation subsystem independent of the performance of the system's other subsystems. To our knowledge there do not exist a generally accepted method or criteria for the evaluation of the standalone iris segmentation subsystem. This paper proposes a novel methodology to compare the performance of different iris segmentation algorithms, applied to different image datasets in a consistent way. The methodology employs the F1 score and an empirical cumulative distribution function. The implementation of the F1 score estimation, adapted to the iris segmentation task is described. Finally the application of the proposed methodology is demonstrated and discussed.

  • 344.
    Gertsovich, Irina
    et al.
    Blekinge Tekniska Högskola, Fakulteten för teknikvetenskaper, Institutionen för tillämpad signalbehandling.
    Nilsson, Mikael
    Lunds Universitet, SWE.
    Ström Bartunek, Josef
    Blekinge Tekniska Högskola, Fakulteten för teknikvetenskaper, Institutionen för tillämpad signalbehandling.
    Claesson, Ingvar
    Blekinge Tekniska Högskola, Fakulteten för teknikvetenskaper, Institutionen för tillämpad signalbehandling.
    Automatic estimation of a scale resolution in forensic images2018Ingår i: Forensic Science International, ISSN 0379-0738, E-ISSN 1872-6283, Vol. 283, s. 58-71Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This paper proposes a new method for an automatic detection of a resolution of a scale or a ruler with graduation marks in the shoeprint images. The method creates a vector of the correlations estimated from the co-occurrence matrices for every row in a shoeprint image. The scale resolution is estimated from maxima in Fourier spectrum of the correlations’ vectors. The proposed method is evaluated on over 500 images taken at crime scenes and in a forensics laboratory. The experimental results indicate the possibility of applying the proposed method to automatically estimate the scale resolution in forensic images. The automatic detection of a scale resolution could be used to automatically rescale a forensic image before the printing this image in “one-to-one” scale. Furthermore, the proposed method could be used to automatically rescale images to an equal scale thus allowing to compare the images digitally. © 2017 Elsevier B.V.

  • 345.
    Ghadami, Soheil
    Blekinge Tekniska Högskola, Sektionen för ingenjörsvetenskap.
    The Evaluation of the Gaussian Mixture Probability Hypothesis Density Filter Applied in a Stereo Vision System2011Självständigt arbete på avancerad nivå (masterexamen)Studentuppsats (Examensarbete)
    Abstract [en]

    In this thesis, the performance of the Gaussian Mixture Probability Hypothesis Density (GM-PHD) filter using a pair of stereo vision system to overcome label discontinuity and robust tracking in an Intelligent Vision Agent System (IVAS) is evaluated. This filter is widely used in multiple-target tracking applications such as surveillance, human tracking, radar, and etc. A pair of cameras is used to get the left and right image sequences in order to extract 3-D coordinates of targets’ positions in the real world scene. The 3-D trajectories of targets are tracked by GM-PHD filter. Many tracking algorithms fail to simultaneously maintain stability of tracking and label continuity of targets, when one or more targets are hidden for a while to camera’s view. The GM-PHD filter performs well in tracking multiple targets; however, the label continuity is not maintained satisfactorily in some situations such as full occlusion and crossing targets. In this project, the label continuity of targets is guaranteed by a new method of labeling, and the simulation results show satisfactory results. A random walk motion is used to validate the ability of the algorithm in tracking and maintaining targets’ labels. In order to evaluate the performance of the GM-PHD filter, a 3-D spatial test motion model is introduced. Here, the two target trajectories are generated in a way that either occlusion or crossing occurs in some time intervals. Then, the two key parameters, angular velocity and motion speed, are used to evaluate the performance of algorithm. The simulation results for two moving targets in occlusion and crossing show that the proposed system not only robustly tracks them, but also maintains the label continuity of two targets.

  • 346.
    Gharari, Farnaz
    Blekinge Tekniska Högskola, Fakulteten för teknikvetenskaper, Institutionen för tillämpad signalbehandling.
    Performance Analysis of Piecewise-and-Forward Relay Network on Rayleigh Fading Channel2015Självständigt arbete på avancerad nivå (masterexamen)Studentuppsats (Examensarbete)
    Abstract [en]

    The rapid changes and developments in cellular and wireless networks aim to provide more reliable communications with high data rate transmission. So far, one solution which is being considered for improving the reliability and eciency of mobile communications is cooperative communications. Implementing di fferent relay scenarios leads to the improvement of the security, ecient, and fast transmission with a good quality of service. The work of this thesis is on the piecewise-and-forward (PF) relay network. This relay protocol is implemented for decreasing the complexity of signal detection at the receiver. Our focus is to investigate the performance of PF relay networks based on the statistical variations which are caused by the fading environment. We considered a relay network with one source and one destination while multiple parallel relays aid the transmission process. At the destination the maximum likelihood (ML) method is implemented for detecting the received signals. Therefore, the probability density function (PDF) of received signals should be used at the ML detector. We analytically investigate the PDF of the received signals, when the transmitted signals are faced with Rayleigh fading. For verifying the theoretical calculations, we use Monte-Carlo simulations in MATLAB to evaluate the results. Afterwards, the bit error rate (BER) has been considered for investigating the performance of the PF relay network over a Rayleigh fading channel. Furthermore, the BER performance of the PF relay network is compared with three well known relay networks, amplify-and-forward (AF), decode-and forward (DF), and estimate-and-forward (EF) relay networks.

  • 347.
    Gholamhosseinpour, Ali
    Blekinge Tekniska Högskola, Fakulteten för teknikvetenskaper, Institutionen för tillämpad signalbehandling.
    Millimeter Wave Radar Interfacing with Android Smartphone2015Självständigt arbete på grundnivå (kandidatexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [en]

    Radar system development is generally costly, complicated and time consuming. This has kept its presence mostly inside industries and research centers with the necessary equipment to produce and operate such a system. Until recent years, realization of a fully integrated radar system on a chip was not feasible, however this is no longer the case and there are several types of sensors available from different manufacturers.

    Radar sensors offer some advantages that are unmatched by other sensing and imaging technologies such as operation in fog, dust and over long distances. This makes them suitable for use in Navigation, Automation, Robotics, and Security systems applications. The purpose of this thesis is to demonstrate the feasibility of a simplified radar system’s user interface via integration with the most common portable computer, a Smartphone, to make it possible for users with minimal knowledge of radar systems design and operation to use it in different applications.

    Smartphones are very powerful portable computers equipped with a suite of sensors with the potential to be used in a wide variety of applications. It seems logical to take advantage of their computing power and portability. The combination of a radar sensor and a smartphone can act as a demonstrator in an effort to bring radar sensors one step closer to the hands of the developers and consumers.

    In this study the following areas are explored and proper solutions are implemented;

    • Design of a control board with capability to drive a radar sensor, capture the signal and transfer it to a secondary device (PC or Smartphone) both wired and wirelessly e.g. Bluetooth.
    • A firmware that is capable of driving the control board and can receive, interpret and execute messages from a PC and or a Smartphone
    • A cross compatible master software that can run on Linux, Windows, Mac and Android OSs and is capable of communication with the firmware/control board
    • Proper analysis methods for signal capture and process purposes
    • Automation of some parameter adjustment for different modes of operation of the Radar System in order to make the user interface as simple as possible
    • A user friendly user-interface and API that can run on both PC and Smartphone 
  • 348.
    Gidla, Vijay Kiran
    Blekinge Tekniska Högskola, Fakulteten för teknikvetenskaper, Institutionen för tillämpad signalbehandling.
    IMPLEMENTATION  AND EVALUATION OF AUDITORY MODELS FOR HUMAN ECHOLOCATION2016Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    Blind  people use echoes to detect  objects  and  to  find their  way, the  ability  being known as human echolocation.   Previous  research  have found some of the  favorable  conditions  for the  detection  of the object,  with  many  factors  yet  to  be analyzed  and  quantified.    Studies  have  also shown  that blind people are more efficient than  the  sighted  in echolocating,  with  the  performance  varying  among  the individuals.   This  motivated the  research  in human  echolocation  to move in a new direction  to get a fuller understanding for the high detection  of the blind.  The psychoacoustic  experiments solely cannot determine  how the superior echo detection  of the blind listeners should be attributed to perceptual or physiological causes.  Along with the perceptual results it is vital to know how the sounds are processed in the  auditory system.   Hearing  research  has led to the  development of several auditory  models by combining  the  physiological  and  psychological  results  with  signal  analysis  methods.    These  models try  to describe how the auditory system  processes the signals.  Hence, to analyze how the sounds are processed for the high detection  of the blind, auditory  models available  in the literature were used in this thesis.  The results  suggest  that repetition pitch  is useful at  shorter  distances  and is determined from the peaks in the temporal  profile of the autocorrelation function computed  on the neural activity pattern. Loudness attribute also plays a role in providing information  for the listeners to echolocate at shorter  distances.  At longer distances  timbre  aspects such as sharpness  information  might be used by the listeners  to detect  the objects.  It was also found that the repetition pitch,  loudness and sharpness attributes in turn  depend on the room acoustics  and type of the stimuli  used.  These results  show the fruitfulness  of combining  results  from different  disciplines  through  a mathematical framework  given by signal analysis.

  • 349.
    GILANI, HASSAN
    et al.
    Blekinge Tekniska Högskola, Sektionen för ingenjörsvetenskap.
    BHUIYAN, RAISUL
    Blekinge Tekniska Högskola, Sektionen för ingenjörsvetenskap.
    Development of ADQ214 user interface in labVIEW.2012Självständigt arbete på grundnivå (kandidatexamen)Studentuppsats (Examensarbete)
    Abstract [en]

    This thesis was conducted in collaboration with Signal Processing (SP) Devices Sweden AB. SP Devices provides digital signal processing solutions for the enhancement of analogue to digital conversion (ADC). Their ADCs facilitate the development of products for Communications, Radio base stations, Radar, Signals intelligence and Test & Measurement. The ADQ series digitizers, from SP Devices, are portable high performance digitizers which incorporate one or more analog inputs, an on-board double data rate (DDR2) memory and USB or PXI Express interface. DDR2 refers to the ability of a computer bus to transfer data on both the rising and falling edges of a clock signal. The ADCaptureLab software is a graphical user interface used to control this digitizer. ADCaptureLab, designed in the C/C++ programming language, is an easy-to-use standalone program which allows for configuration and operation of all ADQ series digitizers from SP Devices. The use of the LabView program from National Instruments forms the backbone of this thesis. LabVIEW (short for Laboratory Virtual Instrumentation Engineering Workbench) is a platform and development environment for a visual programming language from National Instruments. The topic of this thesis was to reproduce the ADCaptureLab user interface using LabView instead of C/C++. The graphical user interface (GUI) developed in LabView should be able to communicate with and control the processing of the ADQ214 digitizer (the digitizer model provided to us) in the same way as the ADCaptureLab. This would involve not only the data capturing and visualization but also digitizer configurations, monitoring of the device and ADQ functions and the analyses of acquired signal and FFT. In order to implement the configuration settings we developed functions for trigger settings (conditions at which a trigger will occur), Analogue Front End settings (AC/DC coupling), clock settings (sets the clock source), data type settings (set sample format), gain and offset setting (sets amplitude gain and mean value), pre-trigger settings (size of pre-trigger buffer), trigger hold off settings ( number of samples to wait for acquiring data after trigger), data acquisition length settings (Length of the acquired signal), continuous and single batch data acquisition, FFT transformation, save, load , and “clear plots” control (resets graph indicators). The functioning of our device may be monitored through the “Status window” (displays connection status of the ADQ device), “Devices window” (displays product information about the ADQ device), “Device monitor window” (returns the status of ADQ-API functions used) and the “Device information window” (returns information related to the revision of the ADQ device). Analyzing the acquired data and its corresponding FFT is made simple with the “Signal Properties” window (displays analyzed data), “Mark Harmonics” control (marks harmonics in the FFT) and the “Mark Signal Props” control (marks the fundamental tone and highest distortion in the FFT). Our LabVIEW GUI efficiently incorporates the features described above. In addition to being able to communicate instructions to the ADQ214 device we are able to monitor its condition and analyze any output. This result serves to show that it is possible to develop a program such as ADCaptureLab in LabVIEW.

  • 350.
    Gillani, Syed Fakhar Uz Zaman
    Blekinge Tekniska Högskola, Sektionen för datavetenskap och kommunikation.
    Investigation of End User IPTV Quality for Content Delivered in MPEG-2 Transport Stream2010Självständigt arbete på avancerad nivå (masterexamen)Studentuppsats (Examensarbete)
    Abstract [en]

    IPTV or Internet Protocol Television is a system where digital television is delivered to the end user using the Internet Protocol. It relies on the same technologies that are used for computer networks and adds new possibilities, such as video on demand, on top of the traditionally broadcasted TV. Video content for IPTV is typically compressed using a MPEG-2 or H.264 (MPEG-4 part 10) compression and sent in an MPEG-2 transport stream over IP. Since TV is a "real time service" packets are delivered using a simple unreliable transmission model and packets may arrive out of order or be lost. Lost packets are normally not re-transmitted since they anyhow would arrive too late to be useful and packet loss will thus decrease perceived quality for the end user. The Master thesis is an investigation of the parameters that affect the perceived quality in MPEG-2 Transport Stream (TS). The aim of the thesis is to develop an objective parametric model1 that can estimate the perceived quality at transport layer. The thesis work includes experimentation performed on High Definition (HD) video sequences with various bit rates and packet loss ratios (PLR).

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