Starting from obvious similarities in operations in LDPC decoding to common neuron models, we have started making this correspondence more obvious. There are manifold possibilities to bridge the two fields, where some applications like denoising offer very obvious links, others appear much more distant.  

Student: Ahmed Elshahed Advisor: Prof. Dr.-Ing. Werner Henkel Dr. Khodr Saaifan Time frame: Spring 2016         Description: In this thesis, we consider the interference cancellation problem for the broadband digital aeronautical communication system. We investigate the L-band digital aeronautical communication system (L-DACS) in the presence of distance measuring equipment (DME) interference. First,

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Student: Yilun Zhang Advisor: Prof. Dr.-Ing. Werner Henkel Time frame: Spring 2016   Description: With increasing significance of wireless transmission, physical layer security becomes a challenging topic resulting from the Shannon’s limit. This work explores physical layer security from the aspect of information theory and discusses key generation and reconciliation by Slepian-Wolf coding and low-density

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  Student: Monder Hamruni Advisor: Prof. Dr.-Ing. Werner Henkel Oana Graur Time frame: Spring 2017           Description: The properties of the physical layer in wireless networks are exploited to generate one-time pads which are subsequently used for secure communication between legitimate users.  Previous measurements testbeds relied mostly on RSSI information, since

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Student: Usama Nadeem Advisor: Prof. Dr.-Ing. Werner Henkel Dawit Nigatu Time frame: Spring 2016   Description: Bidirectional reading processes have been recently incorporated into the Lempel-Ziv family of lossless compression algorithms namely LZ-77, LZ-78 and LZW 84.  Bidirectional compression results in better compression ratios especially if the uncompressed data contains symmetric properties. In this work

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Student: Etta Shyti Advisor: Prof. Dr.-Ing. Werner Henkel Time frame: Spring 2016       Description: All the work in this bachelors thesis is focused on investigating channel reciprocity in powerlines, i.e. performing measurements, which determine channel properties as seen from both the transmitting and receiving side, followed by a comparison and analysis of results.

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Student: Robin Nyombi Schofield Ssenyonga Advisor: Prof. Dr.-Ing. Werner Henkel Time frame: Spring 2015           Description: Neural network rules and coding theory concepts have been associated in the past. It is known that in relation to neural networks, iterative decoding exhibits some nonlinear dynamics. The purpose of this thesis, therefore, is

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Student: Zinan Liu Advisor: Prof. Dr.-Ing. Werner Henkel Time frame: Spring 2015           Description: This Guided Research focuses on frame synchronization for the DMT-based transmission system, which is used on a proposed acoustic sensor network for sonar applications. The time offset estimate not only needs to be robust and accurate to

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Student:  Nazia Sarwat Islam Advisor: Prof. Dr.-Ing. Werner Henkel Time frame: Fall 2014     Description: Physical-layer security options can provide robust security measures in a wireless scenario and is a topic of current interest. In this work, we consider a wireless, reciprocal channel between two legitimate users and assume a frequent physical-layer key generation

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As an alternative to Diffie Hellman’s key exchange protocol, physical layer key generation is discussed based on measurements of reciprocal channels. Due to statistically independent noise together with vector quantization, the keys might not be the same. Hence, the contribution discussed key reconciliation possibilities, either introducing guard bands or LDPC Slepian‐Wolf coding. We derive a

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Student:  Alexandra Filip Advisor: Prof. Dr.-Ing. Werner Henkel Time frame: Fall 2012         Description: Key reconciliation procedures are needed to correct key differences that can arise as a consequence of independent noise at the two ends of a reciprocal link. We assume a line-of-sight channel and use reconfigurable antenna elements to randomize

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Student:  Alexandra Filip Advisor: Prof. Dr.-Ing. Werner Henkel Time frame: Spring 2012         Description: Physical-layer key generation makes use of the reciprocity of wireless time-division duplex (TDD) channels. Both transmission directions experience the same channel, apart from independent noise and quantization effects. The randomness of a mobile channel ensures a certain regeneration

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Student:  Alexandra Filip Advisor: Prof. Dr.-Ing. Werner Henkel, Dr. Mathias Bode Time frame: Spring 2013         Description: Physical-layer security in wireless communication is a challenging topic needed to allow for secure and reliable information transfer, otherwise subject to eavesdropping. In particular, physical-layer key generation methods use the properties of the channel itself

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Student:  Alexandra Filip Advisor: Prof. Dr.-Ing. Werner Henkel Time frame: Fall 2011         Description: We propose a linear programming approach to optimize the variable node degree distribution for a Low-Density Parity-Check code that will provide UEP inside a modulation symbol. Based on a rate maximization criterion, the optimization of the degree distribution

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  Student:  Nazia Sarwat Islam Advisor: Prof. Dr.-Ing. Werner Henkel Time frame: Spring 2013         Description: LZ77, LZ78, and LZW84 are universal lossless data compression algorithms for reducing redundancy. A modified version of these algorithms that takes into account both forward and reverse readings is presented in this work. It is shown

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Student:  Dawit Andualem Nigatu Advisor: Prof. Dr.-Ing. Werner Henkel Time frame: Fall 2013         Description: In the previous project, we used classical multidimensional scaling (CMD) to scale down  the 64 x 64 ECM mutation matrix and 20 x 20 amino acid chemical distance matrix to 2  dimensions (2-D). From the 2-D representations,

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Student:  Dawit Andualem Nigatu Advisor: Prof. Dr.-Ing. Werner Henkel Time frame: Spring 2013         Description: This research contains two separate parts. In the first part, we have used classical multidimensional scaling (CMD) technique to scale down a 64-dimensional empirical codon mutation (ECM) matrix and a 20-dimensional chemical distance matrix to two dimensions

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Student:  Thejani Himalika Fernando Advisor: Prof. Dr.-Ing. Werner Henkel Time frame: Fall 2012         Description: We designed and constructed a suitable circuit for detecting and measuring the power line impulse noise which appears between live and neutral lines as well as between neutral and earth lines. Our study also involved in measuring

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Student:  Mohammad Ismail Hossain Advisor: Prof. Dr.-Ing. Werner Henkel Time frame: Fall 2011         Description: We address noise which is impulsive, non-Gaussian, and follows a heavy-tailed distribution. In wireless communications, often noise is considered as an additive white Gaussian noise (AWGN). In reality, receivers have omnidirectional capability and it receives many signals

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Student:  Asif Ahmed Advisor: Prof. Dr.-Ing. Werner Henkel Time frame: Spring 2011         Description: The project had to aspects. We carried out first multi-antenna measurements of impulse noise in the 2.4 GHz range caused by car ignition and other sources. Additionally, a new circuit was design for wirelines impulse-noise measurements in common

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Student:  Maja Taseska Advisor: Prof. Dr.-Ing. Werner Henkel Time frame: Spring 2010         Description: The combination of multicarrier modulation (OFDM, DMT) and Multiple- Input Multiple-Output (MIMO) transmission significantly improves the quality and efficiency of modern communication systems. The peak-toaverage ratio problem in multicarrier modulation requires additional transmitter side processing which may get

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Student:  Osama Furqan Khan Advisor: Prof. Dr.-Ing. Werner Henkel Time frame: Spring 2010         Description: In contemporary communication systems, Turbo coding is an important channel coding method which results in extremely low bit-error ratios (BER) at signal-tonoise ratios (SNRs) within 1 dB off the Shannon Limit. The BCJR algorithm is used as

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Student:  Jalal Etesami Advisor: Prof. Dr.-Ing. Werner Henkel Time frame: Spring 2013         Description: Lattice Codes show good performance and can approach the capacity of additive white Gaussian noise channel. In the Lattice Codes a codeword x is generated by a linear transformation of corresponding integer message vector d, i.e., x =GTd, where G

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Student:  Oana Graur Advisor: Prof. Dr.-Ing. Werner Henkel Time frame: Spring 2009         Description: Impulse noise has long been known for causing transmission errors. The current thesis presents a method of mitigating impulse noise using a Normalized LMS canceler which takes as reference input the common mode signal and subtracts the adapted

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Student:  Ina Kodrasi Advisor: Prof. Dr.-Ing. Werner Henkel Time frame: Fall 2008         Description: This report studies the encoding of Reed-Solomon codes with consecutive time and DFT domain redundancy. Many data transmission schemes rely on Reed-Solomon codes for error correction, therefore a thorough comprehension of their properties would be very constructive. An

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Student:  Jalal Etesami Advisor: Prof. Dr.-Ing. Werner Henkel Time frame: Fall 2008         Description: We introduce a new algorithm for constructing LDPC codes based on a Protograph. With Protographs, we have a base graph (mother graph), which is duplicated a number of times followed by a special edge permutation obtaining the largest

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Student:  Guftaar Ahmad Sardar Sidhu Advisor: Prof. Dr.-Ing. Werner Henkel, Khaled Shawky Hassan Time frame: Fall 2008         Description: In this work we look into the problem of inter-user interference in multiuser MIMO systems. We disscuss two different SDMA MIMO schemes. The first scheme, the orthogonal SDMA, completely eliminates the inter-user interferance. It

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Student:  Guftaar Ahmad Sardar Sidhu Advisor: Prof. Dr.-Ing. Werner Henkel, Khaled Shawky Hassan Time frame: Spring 2008         Description: In this work, we consider the downlink transmission of a multiuser system. Both the Single Input Single Output (SISO) and Multiple Input Multiple Output (MIMO) antenna systems between the base station (BS) and the

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Student:  David Kronmüller Advisor: Prof. Dr.-Ing. Werner Henkel, Neele von Deetzen Time frame: Spring 2008         Description: The demand for higher communication data rates is immense in the era of high quality multimedia content. The issue at hand is to increase data transfer rates while improving error tolerance lev- els. Turbo codes

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Student:  Behrouz Touri Advisor: Prof. Dr.-Ing. Werner Henkel Time frame: Spring 2008         Description: Binary linear codes are one of the main tools for error-control coding over telecommunication channels and data storage devices. However, despite of having very simple encoder structures, their optimum decoding is usually a hard problem in practice. In

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Student:  Karim Ibrahim Khashaba Advisor: Prof. Dr.-Ing. Werner Henkel Time frame: Spring 2007         Description: This thesis examines the benefits of using adaptive modulation in terms of bit error probability. Specifically, we examine the performance enhancement made possible by using linear prediction along with channel estimation in conjunction with adaptive modulation. We

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Student:  Guftaar Ahmad Sardar Sidhu Advisor: Prof. Dr.-Ing. Werner Henkel, Neele von Deetzen Time frame: Spring 2006         Description: The distance spectrum of an (n,k)-convolutional code is given by a transfer function T(W,D,L). where W,D,L represent the input weight, the output weight, and the length of the sequence, respectively. The task was

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Student:  Behrouz Touri Advisor: Prof. Dr.-Ing. Werner Henkel Time frame: Spring 2007         Description: In this project, our objective was to study the channel response of water filled ducts. Our motivation to do such a project was to see the possibilities of information transmission using water-filled pipes. Since water pipes are frequently

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Student:  Vlad-Andrei Lazar (undergraduate student at IUB) Advisor: Prof. Dr.-Ing. Werner Henkel Time frame: Spring 2005     Description: We calculate the error probabilities in Reed-Solomon coded words taking into account both errors and erasures. This is calculated for Gray coded QAM constellations assuming only one bit to be erroneous. The occurring errors and erasures

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Student:  Neele von Deetzen (diploma student of the University of Bremen and now PhD student at Jacobs University) Advisor: Prof. Dr.-Ing. Werner Henkel, Prof. Dr.-Ing. Karl Dirk Kammeyer Time frame: August 31, 2004, February 28, 2005         Description: In this work, we discussed possible solutions for achieving unequal error protection based on

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Student:  Vimtakhul Azis (master program FH Darmstadt) Advisor: Prof. Dr.-Ing. Werner Henkel Time frame: February – July 2003 Grants: We appreciate funding by Infineon       Description: The major drawback of multi-carrier transmission is the high peak-to-average power ratio of the time-domain signal resulting from the combination of many carriers (central limit theorem). Without countermeasures,

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Editors: Michael Steinmann, Holger Mehrholz Advisor: Prof. Dr.-Ing. Werner Henkel Time frame: 02/24/2003 – 04/24/2003       Description:In the Studienarbeit a safe web environment is to be provided, which exhibits the following outlined characteristics. As contents of the associated Web environment, sites are to be written, which describe the area and activities and additionally

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We investigate nonstationary disturbances in wireline and wireless systems. In wireline, we make us of the common-mode signal to cancel impulse noise from the differential mode or use the common mode to forecast error positions. In wireless, we model impulse noise on antenna arrays caused by ignition, electrical machines, MRI equipment, and alike. Furthermore, we

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    Work in xDSL focuses on problems of multicarrier transmission, like PAR reduction, time-domain equalization, bit-allocation. To name just a few outcomes of this research:    First real capacity optimizing time-domain equalizer    PAR reduction scheme which is widely used (many million installations)    A bit-allocation scheme allowing for arbitrary SNR margins between priority

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  Our MIMO research focuses on the treatment of imperfect channel information and a possible realization of UEP properties just as in the case of multicarrier transmission.  We consider multi-user bit loading, multi-user hierarchical modulation, LDPC coded hierarchical modulation.

  In a joint project with life sciences, we investigate the communications and code properties of the DNA. Our share deals with reasoning of the codon/aminoacid encoding structure, the error-protection, and source coding properties, whereas Prof. Mushelishvili’s group concentrates more on the influences of the three dimensional orientation leading to analog control mechanisms in gene

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