# Open Theses

You may also contact one of our doctoral candidates directly, if you are interested in a Bachelor or Master thesis, a student job, an "Ingenieurspraxis" or a "Forschungspraxis". It often happens, that topics are being prepared which are not adverdised yet. It may also be possible to find a topic matching your specific interests.

Please include a **curriculum vitae** together with a **list of attended courses** when applying for a thesis.

If your "Ingenieurspraxis" is selected to be supervised by one of our professors, please hand in the documents to Doris Dorn (Room N2401).

## Bachelor Theses

Implementation of a General Purpose LDPC Encoder | ||

In the beginning of the thesis, the student will perform a literature research on existing general purpose LDPC encoding strategies and find out which variants are used in practical implementations in standards (Wifi, CCSDS, etc.). Next, the student will focus on the implementation of a scheme as described by the authors of [1]. As a programming language, we will target both C and Matlab. [1] T. J. Richardson and R. L. Urbanke, “Efficient encoding of low-density parity-check codes,” IEEE Trans. Inf. Theory, vol. 47, no. 2, pp. 638–656, Feb. 2001. | ||

Supervisor: Fabian Steiner |

Development and Implementation of an Algorithm for a Bandwidth-Optimized Transmission of "Start-Over" media via Satellites. | ||

Supervisor: Fabian Steiner, Firma SES/MX1 |

LDPC Decoder implementation on FPGA | ||

Feasible decoding complexity is a major criteria for any decoding algorithm. LDPC Codes have linear decoding complexity, which makes them interesting for various applications. The aim of this bachelor thesis is to implement one specific LDPC Code on hardware starting from a software implementation. Week 1: get familiar with LDPC Codes Week 2: implement LDPC decoder in software Week 3-8: implement LDPC decoder on FPGA Week 8-9: write your thesis Requirements: some experience with FPGAs |
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Supervisor: Peihong Yuan, Patrick Schulte, Georg Böcherer |

## Master Theses

A Deterministic Approach to the Gaussian Multiple-Input Multiple-Output (MIMO) Broadcast Channel | ||

Multi-user communication systems (such as wireless systems) are different than point to point channels in two key aspects; namely, the broadcast nature of transmissions (e.g., wireless transmissions can be picked up by any receiver in the vicinity of the transmitter) and the superposition (e.g., a wireless receiver picks up a linear combination of transmissions from all transmitters in its vicinity). Recently a deterministic approach to multi-user information theory has proved promising by achieving progress in some of the long-standing open problems by finding approximate solutions. The idea behind a deterministic approach, on a high level, is to focus on the interaction of signals rather than the background noise, through a simpler appropriate model; find exact solutions for the simpler model; and then translate the intuitions and techniques to new techniques and/or approximate solutions on noisy models. The goal of thesis is to undertake a deterministic approach to Gaussian MIMO broadcast channels. Prerequisite: Linear Algebra, Information Theory |
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Supervisor: Shirin Saeedi |

Role of Feedback in Broadcasting | ||

This project intends to investigate the role of feedback in broadcast channels. More information available upon request.
Pre-requisite (at least one of the following): Basic knowledge of Network Coding (see [2]) Basic knowledge of Algorithms Basic knowledge of Information Theory |
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Supervisor: Shirin Saeedi |

Code and Algorithm Design for Physical-layer Security | ||

We are looking for motivated students to work on algorithm and code design for privacy and security applications. For realistic channel models, we want to implement a set of codes and algorithms to analyse their complexity, reliability, privacy, and secrecy performance. Pre-requisites: Information theory, one of the Channel Coding lectures given by LNT |
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Supervisor: Onur Günlü |

Error Correcting Codes for Insertion/Deletion Errors | ||

The discussion of synchronization errors, like insertions and deletions of symbols into codewords goes back to the early 1960's. Still, little is known about these kinds of errors and basic questions, like the capacity of the binary deletion channel remain unsolved. This stems from the fact that errors in the insertion/deletion metric are fundamentally different from the well-researched substitution errors and conventional error correcting codes cannot be applied on these kinds of errors. Current research, and the topic of this Master thesis, is directed towards finding the minimum redundancy of such codes and developing constructions that can correct insertion and deletion errors. Prerequisites:
You should have good knowledge in linear Algebra and interest in channel coding. |
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Supervisor: Andreas Lenz |

Simulation of Improved Staircase Code Decoding | ||

Staircase codes, as introduced in 2011 by Smith et. al. [1], are a hardware friendly code design for error correction in optical communication systems. However, the choices of parameters such as block size and code rate that achieve a desired output bit error rate are limited by the error floor of the decoder. A new and improved decoder has been devised [2], allowing for staircase codes with a scope of new parameters to be considered for optical communication. While estimations show the significant improvements, the high throughput required to simulate the error floor can, in software, only be achieved with an efficient and parallelisable implementation. The main goal of the thesis is the implementation and simulation of the new decoder in C in order to provide further evidence for the estimated performance. |
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Supervisor: Lukas Holzbaur |

Application of Machine Learning in Wireless Communications | ||

See here thesis_TUM_ML.pdf. | ||

Supervisor: Georg Böcherer, Prof. David Gesbert, Paul de Kerret |

Fundamental Outerbounds of Wireless Communications with Imperfect Channel State Information at the Transmitter | ||

See here thesis_TUM_IT.pdf. | ||

Supervisor: Georg Böcherer, Prof. David Gesbert, Paul de Kerret |

Generalized Concatenated Codes with BCH and Polar Codes | ||

Polar Codes [1] are a class of channel codes that are proven to achieve the capacity of binary input discrete memoryless channels, asymptotically in the block length. Nevertheless, the performance for finite block lengths is not competitive with state-of-the-art channel codes like Turbo or LDPC codes. In [2], outer cyclic redundancy check (CRC) codes and list decoding are used to improve the distance properties and the performance of polar codes. The main idea of generalized concatenated codes (GCC) [3] is to concatenate several inner and outer codes to improve the distance properties of the resulting overall code. The goal of the thesis is to implement generalized concatenated coding schemes using Polar codes and other codes like BCH or CRC codes and to analyse and discuss the distance properties and the performance of the schemes.
[2] I. Tal and A. Vardy, "List Decoding of Polar Codes," in IEEE Transactions on Information Theory, vol. 61, no. 5, pp. 2213-2226, May 2015. [3] ZYABLOV, Victor; SHAVGULIDZE, Sergo; BOSSERT, Martin. An introduction to generalized concatenated codes. European Transactions on Telecommunications, 1999, 10. Jg., Nr. 6, S. 609-622. |
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Supervisor: Tobias Prinz, Antonia Wachter-Zeh |

Post-Quantum Cryptography on Automotive Microcontroller | ||

Public-key cryptography (PKC) is the foundation for establishing secure communication chan-
nels between multiple parties. It is a critical piece of technology for highly interconnected
networks and therefore vital for the automotive world. However, due to the fear of the immi-
nent arrival of quantum computers, traditional PKC algorithms such as RSA and ECC, are
beginning to be considered risky for implementations in secured devices. This is especially true
for applications with long life-cycle, if the devices deployed in the field are hard to update. In
fact, if capable quantum computers become available, cryptographic systems based on the inte-
ger factorization problem and the (elliptic curve) discrete logarithm problem could be attacked
in polynomial time due to the work of Shor [8]. As a reaction, the National Security Agency
(NSA) announced the intention to transition towards quantum-resistant, i.e., post-quantum,
cryptography for governmental usage in the foreseeable future. Concurrently, the National
Institute of Standards and Technology (NIST) of the United States has already started mov-
ing forward with efforts towards standardization. Beside PKC, also secret-key cryptography
(SKC) is affected by the advent of quantum computers. Grover’s quantum algorithm [3] does
speed up attacks and doubling the key size can effectively block these attacks. In a real-time
and safety-critical environment like high-speed in-vehicle car networks doubling the key size
leads to an increase of additional delays in processing of data due to elaborated symmetric en-
/decryption and authentication techniques (currently a cipher-based message authentication
code as proposed in [2] is used in Controller Area Network (CAN) in vehicle bus systems).
Scope of the Thesis In this Master’s thesis we want to: 1. Identify, evaluate and implement post-quantum asymmetric PKC systems (as, e.g., [2, 4, 5, 6, 7]) for the automotive context on an Infineon Aurix-2G microcontroller. 2. Improve code-based post-quantum PKC systems w.r.t. a possible reduction of the key size and the speed and complexity of the en- and decryption algorithm (as, e.g., [6, 7, 9]). 3. Investigate mechanisms (in soft- and hardware) to support post-quantum PKC and SKC systems in automotive microcontrollers (e.g., extended key storage, hardware primitives). References [1] D. J. Bernstein, T. Lange, and C. Peters. “Attacking and Defending the McEliece Cryp- tosystem”. Ed. by J. Buchmann and J. Ding. Vol. 5299. Lecture Notes in Computer Science. Cited by 0139. Springer Berlin Heidelberg, 2008, pp. 31–46. [2] M. J. Dworkin. SP 800-38B. Recommendation for Block Cipher Modes of Operation: The CMAC Mode for Authentication. Tech. rep. Gaithersburg, MD, United States: National Institute of Standards & Technology, 2005. [3] L. K. Grover. “A fast quantum mechanical algorithm for database search”. arXiv:quant- ph/9605043 (1996). arXiv: quant-ph/9605043. [4] J. Hoffstein, J. Pipher, and J. H. Silverman. “NTRU: A ring-based public key cryptosys- tem”. en. Algorithmic Number Theory. Ed. by J. P. Buhler. Lecture Notes in Computer Science. DOI: 10.1007/BFb0054868. Springer Berlin Heidelberg, June 1998, pp. 267–288. [5] R. J. McEliece. “A Public-Key Cryptosystem Based On Algebraic Coding Theory”. Deep Space Network Progress Report 44 (Jan. 1978), pp. 114–116. [6] R. Misoczki, J. P. Tillich, N. Sendrier, and P. S. L. M. Barreto. “MDPC-McEliece: New McEliece variants from Moderate Density Parity-Check codes”. 2013 IEEE International Symposium on Information Theory Proceedings (ISIT). July 2013, pp. 2069–2073. doi: 10.1109/ISIT.2013.6620590. [7] N. Sendrier. “QC-MDPC-McEliece: A public-key code-based encryption scheme based on quasi-cyclic moderate density parity check codes”. en. Nov. 2014. [8] P. W. Shor. “Polynomial-Time Algorithms for Prime Factorization and Discrete Loga- rithms on a Quantum Computer”. SIAM J. Comput. 26.5 (1997), pp. 1484–1509. doi: 10.1137/S0097539795293172. [9] R. Zalman and A. Mayer. “A Secure but Still Safe and Low Cost Automotive Communi- cation Technique”. Proceedings of the 51st Annual Design Automation Conference. DAC ’14. New York, NY, USA: ACM, 2014, 43:1–43:5. doi: 10.1145/2593069.2603850. |
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Supervisor: Antonia Wachter-Zeh, Infineon Technologies (Laurent Heidt, Alexander Zeh) |

Protected Code-based Post-Quantum Security | ||

The foreseeable breakthrough of quantum computers represents a risk for communication which uses public-key cryptography. In order to prepare for such an event, embedded devices must integrate post-quantum cryptography, a set of algorithms based on mathematical problems that remains secure even in the presence of the quantum computers. Code-based is one of the most promising post-quantum cryptography. However, the implementation of code-based cryptography has two main challenges: i) satisfy performance and power constraints; and ii) resist side-channel attacks, which uses leakages derived from the implementation (timing, power or electromagnetic characteristics) to retrieve the secret information. The goal of this thesis is to implement a protected version (resistant to side-channel attack) of the newest version of the Gabidulin-Paramonov-Tretjakov code-based post-quantum cryptosystem. This Master thesis will be supervised by Dr. Johanna Sepúlveda (Chair of Security in Information Technology) and Prof. Dr.-Ing. Antonia Wachter-Zeh (Professorship for Coding for Communications and Data Storage). Some of the following tasks might be covered: - Getting familiar with Code-based Post-quantum security - Getting familiar with Gabidulin codes - Getting familiar with secure implementation - Secure C/VHDL implementations - Performance evaluation - Security evaluation The thesis can be done in German or English language. Requirements: - VHDL/Verilog or C/C++ programming skills - Basic knowledge in security concepts - Basic knowledge in channel coding or information theory Literature: - Daniel J. Bernstein, Johannes Buchmann, and Erik Dahmen, editors. Post-quantum cryptography. Mathematics and Statistics Springer-11649; ZDB-2-SMA. Springer Berlin Heidelberg, 2009. - M. Taha, T. Einsenbarth. Implementation Attacks on Post-Quantum Cryptographic Schemes. IACR, 2015. - P. Loidreau. An evolution of GPT cryptosystem. In Proceedings of ACCT 2016, Fifteenth International Workshop on Algebraic and Combinatorial Coding Theory, Albena, 2016. Contact: Dr. Johanna Sepúlveda (Doutora em Ciencias, Microeletrônica, University of São Paulo). Mail: johanna.sepulveda@tum.de, tel.: +49 89 289 28256, room N1009. Prof. Dr.-Ing. Antonia Wachter-Zeh Mail: antonia.wachter-zeh@tum.de, tel.: +49 89 289 23495, room N4402. |
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Supervisor: Antonia Wachter-Zeh, Johanna Sepúlveda (Chair of Security in Information Technology, TUM) |

Analyzing the Storage of Data in Synthetic DNA | ||

Encoding digital data into synthetic DNA is a novel approach for data storage. Due to its natural robustness and extent in molecular sizes, it can be used for long-term and very high-density archiving of data. Since the DNA molecules can be corrupted by thermal process and the writing/reading process of DNA molecules can be faulty, it is necessary to encode the data using error-correcting codes. In this thesis, we analyze the type of errors that occur during read and write cycles using measurements results from synthesis and sequencing experiments. Further, we aim for finding coding solutions to guarantee reliable storage. | ||

Supervisor: Andreas Lenz |

Designing codes for secret key generation and extracting the secret bits in left over hash lemma | ||

The source model of secret key generation deals with the idea of Alice and Bob generating a key in a distributed manner from correlated observations. This key must be kept secret from an evesdropper. In this internship/thesis the student will start by looking at a simpler model which corresponds to the left over hash lemma. The student will build on some preliminary work done by me to design codes for the extraction of left over hash in a simple setting. After this the student will extend the work to design codes for distributed secret key generation for the source model. | ||

Supervisor: Rana Ali Amjad |

MIMO Multiport Communications | ||

The topic of the thesis is to develop a simulator for MIMO communications including the transmit and receive RF frontends of a single user link. The simulator should be able to support different types of antenna elements and array configurations as well as matching circuits and amplifier models. In addition it should be able to estimate rates of communication over deterministic and stochastic channels. | ||

Supervisor: Andrei Nedelcu |

Rate-Distortion Theory for Sparse Sources | ||

Rate-Distortion Theory for Sparse Sources
This project investigates information theory limits for the lossy compression of sparse sources.
Motivated by the recent mathematical theory Compressed Sensing that deals with the efficient acquisition and reconstruction of sparse signals, we try to determine the fundamental limits of digitally storing data created by such sources.
A sparse source emits a string of symbols of which - loosely speaking - only a few contain information. There are different ways to model these sources. An example is the Gaussian spike source which emits a Gaussian symbol with probability p and a zero with probability 1-p.Possible directions of a project are: - Investigating different source models - (Numerically) determining the rate distortion function of a sparse source - Computing finite length performance bounds for sparse sources Prerequisites: - Information Theory (must) - Pleasure with mathematics (must) - Multiuser information theory (beneficial) |
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Supervisor: Lars Palzer |

## Forschungspraxis or MSCE Internships

Code design for Physical Layer Security | ||

Wiretap channel represents the basic setup for physical layer security. It has been extensively studied in the last four decades and the fundamental limits of communication for this channel are known in a wide variety of scenarios. Nevertheless the only explicit code construction that can achieve wiretap secrecy capacity uses Polar codes. Designing codes for secrecy involve the combined design of codes for reliability and channel resolvability. In 2015 a new coding scheme for channel resolvability was introduced by Amjad and Kramer. The aim of this internship is to combine this channel resolvability code with existing channel codes in order to design wiretap code. | ||

Supervisor: Rana Ali Amjad |

Vector Network Coding Based on Rank-Metric Codes | ||

Supervisor: Antonia Wachter-Zeh |

Characterization of the effect of filtering on Four Wave Mixing | ||

The nonlinearity of the fiber optic channel produces several frequency mixing effects, namely Cross Phase Modulation (XPM) and Four Wave Mixing (FWM). The repeated use of filters along the fiber reduces these effects, and improves channel isolation. In this thesis, we aim to find a way to characterize the FWM interference, and to find out how much of it is removed by the filters. | ||

Supervisor: Francisco Javier Garcia Gomez |

Code Design for Secret Key Generation/ Left over Hash Lemma | ||

The source model of secret key generation deals with the idea of Alice and Bob generating a key in a distributed manner from correlated observations. This key must be kept secret from an evesdropper. In this internship/thesis the student will start by looking at a simpler model which corresponds to the left over hash lemma. The student will build on some preliminary work done by me to design codes for the extraction of left over hash in a simple setting. After this the student will (if time permits) extend the work to design codes for simple cases of distributed secret key generation for the source model. | ||

Supervisor: Rana Ali Amjad |

# Theses in Progress

## Bachelor Theses

Alberto Diago Gallardo : Atmospheric Influence on Free Space Optical Communications | ||

The work is based on Free Space Optical (FSO) communications and will include the following parts: • Case Study: Ground-to-Ground laser Links: o Link budget calculations; (Done) o Tracking Power budget calculations; o Scintillation analysis (optional: atmospheric simulations and fade statistics); (Ongoing) o Atmospheric Attenuation: Link availability calculations. (Ongoing) • Support the design, integration of testing of the “Frame-Steering Concept” as a demonstrator terminal for static links. (Ongoing) • Outdoor link demonstration and measurement campaign. • Analysis and evaluation of the measurement data. | ||

Supervisor: Norbert Hanik, Luis Martin Navajas |

Alyssa Akremi: Reduced complex precoding for CoMP massive MIMO sparse Channels | ||

In this thesis, we investigate the low complex algorithms applicable to Zero-Forcing process of Coordinated Multi Point (CoMP) sparse channel matrices | ||

Supervisor: Amir Ahmadian |

Houssem Amami: Inter-channel interference in optical narrow-band multi-channel systems with distributed filters | ||

The nonlinear nature of the fiber optic channel produces frequency mixing and the appearance of spurious frequencies. Careful design of the fiber can mitigate this effect by removing the spurious components, but there is still residual interference between channels in multi-channel systems. In this thesis, narrow-band channels are considered, and the nature of the residual interference is explored. | ||

Supervisor: Francisco Javier Garcia Gomez |

Kai Tan Kian: Performance Analysis of HARQ transmission schemes | ||

The student is supposed to implement different HARQ strategies and compare them using. | ||

Supervisor: Patrick Schulte |

Sirine Ammar: Community Detection in Dramatic Plays | ||

We are given the scene configuration of a dramatic play in the form of a matrix that links characters to scenes. A matrix entry is 1 if the corresponding character is present in the corresponding scene and 0 otherwise. Based on this matrix and on the generalized formulation of information-theoretic co-clustering by Clemens Blöchl, we want to cluster characters into meaningful groups and compare the results with those obtained from text analysis. | ||

Supervisor: Bernhard Geiger, Rana Ali Amjad |

Rouven Fischer: Investigation into control concepts of modern industrial automation | ||

Supervisor: Norbert Hanik |

Mohamed Nabil Babai: How many clusters? | ||

In this thesis, we investigate heuristics for determining the number of clusters in cluster analysis. We place focus on popular clustering techniques such as k-means and spectral clustering, but we will also summarize heuristics for hierarchical methods. After doing a literature survey, small Matlab experiments will illustrate the results. | ||

Supervisor: Bernhard Geiger, Rana Ali Amjad |

Fares Charfi: Transform Selection for Secret-key Storage with Physical Identifiers | ||

Binding secret keys to physical identifiers (e.g., physical unclonable functions) is a secure and cheap alternative to storing a key in a non-volatile memory to provide security to Internet of Things (IoT) applications. Key-binding schemes require an information reconciliation step due to the noisy nature of physical outputs. The student will start with a literature review about the computational and hardware complexity of standard transforms. Later, the results of the first part will be used to improve the transform-coding algorithm that binds secret keys to physical identifiers, proposed by Günlü et al., so that one can use simpler low-complexity channel codes for error correction. Student will also implement the complete key-binding algorithm by using the improved transform-coding steps. |
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Supervisor: Onur Günlü, Karl-Tasnad Kernetzky |

Mohamed Ibn Haj Hmida: Transform Optimization for Secret-key Generation from Correlated Physical Outputs | ||

The main aim of the thesis is to find useful methods available in the literature to solve an optimization problem that gives the optimal transform for our security and privacy algorithm. In the first part of the thesis, the student should get familiar with the basics of physical unclonable functions (PUFs) and the transform-coding algorithm proposed by us. With this background, the optimization problem to be solved for our specific security application will be accurately defined by the student with some guidance. The student will later study different methods in the literature used for solving a certain class of optimization problems and if possible decide which methods are the best for us. The student will also attempt to (partially) solve the problem. Final part of the thesis will include MATLAB simulations with different transform and mapping options for comparison. |
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Supervisor: Onur Günlü, Bernhard Geiger |

Khalil Messaoudi: State Evolution Analysis of Quantized Compressive Sensing | ||

The subject of this Bachelor’s thesis is the asymptotic performance analysis of scalar quantized compressive sensing (CS) under approximate message passing reconstruction. | ||

Supervisor: Lars Palzer |

Timothée Felicio: Implementation of Lower Bounds for the Error Probability of Gaussian Channels for Finite Blocklengths | ||

In 1959, Shannon derived a sphere-packing bound that offers a lower bound on the decoding error probability for a Gaussian channel. This bound does not take any modulation constraints into account. In 1967, Shannon, Gallager, and Berlekamp derived a sphere-packing-bound that also considers modulation constraints. Nevertheless, the 1967 bound is not very close for short and moderate blocklengths. In [1], an improvement of the sphere-packing bounds is provided that is applicable to short lengths and considers modulation constraints. The goal of the thesis is to analyze and implement this bound. [1] A. Valembois and M. P. C. Fossorier, "Sphere-packing bounds revisited for moderate block lengths," in IEEE Transactions on Information Theory, vol. 50, no. 12, pp. 2998-3014, Dec. 2004. |
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Supervisor: Tobias Prinz |

Safwen Dridi: HDL Implementation of a Convolutional Interleaver | ||

The student's task is to do research about interleaver theory, explore some implementations in MATLAB and finally implement a convolutional interleaver in VHDL or verilog. | ||

Supervisor: Karl-Tasnad Kernetzky |

## Master Theses

Mustafa Cemil Coskun: Successive Cancellation Decoding of Product Codes | ||

Product codes were introduced by Peter Elias in 1954. He showed that the bit error probability can be made arbitrarily small by constructing a multidimensional product code with a positive code rate although it was far below the capacity limit. After almost half a decade, Erdal Arıkan has come with a channel code, which is provably capacity-achieving under successive cancellation decoding as block length tends to infinity. The construction of both codes shows many similarities, which can be exploited. The thesis will investigate these similarities between two classes of codes and, in particular, it will borrow some tools from polar code setting and apply to product codes, e.g. successive cancellation decoder. After finding some theoretical results, the work will be concluded by implementing a simulator for product codes to show whether the findings are accurate or not. |
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Supervisor: Dr. Gianluigi Liva (DLR) |

Keykavoos Afghahi: Methods for Adaptive Channel Allocation in a Multi-cell System | ||

Supervisor: Markus Staudacher, Neda Petreska (Frauenhofer ESK) |

Daniel Sander: Development of a measurement device for characterization of the signal quality in optical satellite-to-ground communications | ||

The Institute of Communications and Navigation develops new systems and algorithms for optical communications with satellites and aircraft. The atmosphere significantly degrades signal quality, which can be seen in phase and intensity distortions as well as signal blockage by clouds. The institute operates an optical ground station to characterize these distortions and conducts measurement campaigns with satellites and aircraft. The new measurement device shall be designed to be directly attached aside the main receiver reflector of a ground station. The measurement device shall be independent from the receiver reflector e.g. the optical telescope but shall use the same tracking mount. The prime application will be the characterization of channel impairments at existing ground station sites worldwide, either of optical or RF type. This drives the requirement that the measurement device must be weatherproof taking into account typical climate conditions at ground station sites and it shall be of a small form factor (2” system). To ensure simple and continuous operations it must be able to be operated autonomously. In this work, this measurement device for signal quality shall be designed, assembled and tested. The design shall consider boundary conditions given by possible installations on an optical or RF receive antenna system as well as availability of possible signals sources in space. This includes analysis of characteristics of different antenna types (optical/RF), recommendations given by standardization activities regarding the space-to-ground link and expected dynamics and signal levels from potential test sources. | ||

Supervisor: Norbert Hanik, Dirk Giggenbach / Florian Moll / Hennes Henniger |

Kairen Liu: Information Theoretic Analysis of Neural Networks | ||

Various types of neural networks have gained a lot of attention in recent years and have found numerous practical applications with impressive results. Albeit their success, their behaviour is not very well understood mathematically. The aim of this thesis is to approach the topic from an information theoretic perspective and see if one can use insight from information and coding theory to analyze/design neural networks for specific applications. | ||

Supervisor: Rana Ali Amjad, Bernhard Geiger |

Zafzouf Ghassen: Investigation into signal wave-forms for 5G & information theoretic analysis of MIMO OFDM systems | ||

5G communication systems aim to put a large range of devices onto a network, ranging from high bandwidth systems which can transfer video and large files to small devices which only sporadically send data. Similarly the devices may be battery powered or not. The problem that can exist is that many modern communication systems are based on OFDM modulation which when used by multiple users simultaneously can have problems with synchronization, bit resolution, and the need to achieve good channel estimation. Our goal will be to characterize the fundamental information theoretic limits of such communication systems,as well as to design practical communication schemes that can approach these limits. This project will look into MIMO OFDM systems with a view to improve them towards being suitable for 5G communication systems. | ||

Supervisor: Markus Staudacher |

Qionghui Cao: Partial Parallel LDPC Decoder implementation on FPGA | ||

Supervisor: Peihong Yuan |

Jianwei Zhang: Probabilistic Signal Shaping for Short-Reach Optical Fiber Systems | ||

Optical fiber systems form the backbone of the internet. Despite their large usable bandwidth, they are going to running out of capacity due to an increasing demand for services such as high-definition video streaming. In order to obtain the largest possible transmission rates for a fixed link, a shaped input should replace the common uniform input. In particular, non-iid inputs lead to less fiber nonlinearities, which improves the system performance. This Master thesis investigates such temporally correlated fiber inputs. | ||

Supervisor: Tobias Fehenberger |

Longxi Xu: FPGA implementation of Polar Encoder and Simplified Successive Cancellation Decoder | ||

Supervisor: Peihong Yuan |

Niklas Jünger: Error Correction for Data Storage in DNA | ||

Supervisor: Andreas Lenz |

David Ginthör: Development of a packet level encoding scheme and network protocol for a Hybrid-FSO/RF-Link | ||

The Institute of Communication and Navigation of DLR developed a high rate Free Space Optical (FSO) downlink from an airborne to a ground station. However, it suffers from limited availability, as weather and atmospheric conditions significantly influence the signal link. Furthermore, the optical link is unidirectional and thus does not allow any flow-control. For operational purposes, the system also includes a bidirectional RF link. The objective of the Master’s Thesis is to develop a hybrid system that utilizes both transmission technologies – FSO and RF – to exploit the advantages of each. We will study how to increase performance of the unidirectional optical link by utilizing the bidirectional RF link to establish flow-control. Additionally, a switching algorithm shall be developed, which ensures uninterrupted data transmission in cases where only individual links are usable in order to maximize link availability and thus throughput of the system. This involves designing a protocol, which allows transmission over both links depending on the state of the channel. Information of the optical channel is acquired by analyzing statistics of the connection derived from the received data at the optical terminal. The software development includes analyzing and finding suitable transport protocols and focuses on efficient low-level programming in order to achieve high data rates of up to 10Gbit/s. Further, we will investigate a data-encoding scheme on the application layer to find possible solutions to increase reliability of packet integrity and hence robustness to packet losses over the optical link. The main challenge will be handling high data rates without the possibility to employ any sort of acknowledgment due to the lack of an uplink in the FSO. | ||

Supervisor: Norbert Hanik, Dr. Julio Ramirez, DLR |

Michael Reinsch: Latency-Measurement and -Validation of Safety-Critical Functions on Vehicles and Test Benches | ||

In dieser Masterarbeit werden Latenzzeitmessungen sicherheitsrelevanter Funktionen der Längsdynamik „Abstandsregeltempomat“ und „Notbremsassistent“, sowie der aktiven Sicherheit „Auffahrwarnung“, von Kraftfahrzeugen durchgeführt. Zu Beginn werden die für die Funktionen relevanten Anforderungen und Wirkketten analysiert. Eine Wirkkette ist aus Steuergeräten, Sensoren, Aktoren und Datenbussen zusammengesetzt. Das Architekturmodell wird um Latenzzeitanforderungen ergänzt, sodass ein Sollmodell der Funktionen hinsichtlich Latenzen entsteht. Anschließend wird ein Konzept eines Messaufbaus erstellt, in dem die in der Architektur relevanten Meßpunkte definiert werden. Die benötigte und zur Verfügung stehende Messtechnik wird analysiert. Daraufhin werden Messungen am Hardware-in-the-Loop-Prüfstand sowie am Realfahrzeug durchgeführt. Die Meßergebnisse werden mit dem Sollmodell evaluiert. | ||

Supervisor: Norbert Hanik, Sebastian Vöst, M.Sc., BMW Group |

Maximilian Schädler: Frequency- and Time-Domain Enhanced Gaussian Noise Models for Fiber-Optic Communication Systems | ||

Modern optical communication sytems suffer from nonlinear fiber effects that are the main limiting factor to increased spectral efficiencies. The split-step Fourier method, which is used to simulate the propagation of an optical signal through fiber, is computationally highly complex, which makes a detailed analysis of the impact of various system parameters on the fiber nonlinearities practically impossible. In this Master Thesis project, enhanced Gaussian noise models in the frequency and time domain are used to evaluate to optical communication systems. The aim is to find approximate solutions that describe the impact of the fiber nonlinearities on the signal. | ||

Supervisor: Tobias Fehenberger |

## Ingenieurspraxis

Mahmoud Marcam Helmy: Erstellung einer App für Smartphones der BITS mobile ERP Linie auf Basis von IOS Plattformen | ||

Supervisor: Gerhard Kramer, BITS better it solutions GmbH, Wallenmahd 47, A-6850 Dornbirn |

Lukas Püttner: Evaluierung verschiedener Tools zur Extraktion und Auswertung von Metadaten aus IP-Verkehrsdaten | ||

Supervisor: Norbert Hanik, ESG Elektroniksystem- und Logistik GmbH, 82256 Fürstenfeldbruck |

Francesco Montanari: Dynamic Dead Pixel Correction | ||

Supervisor: Norbert Hanik, Fa. ARRI, Arnold & Richter Cine Technik GmbH & Co KG, München, Fr. E. Kögel |

Barbara Lenz: Durchführung/Auswertung von RCS-Messungen | ||

Supervisor: Gerhard Kramer, MBDA Deutschland GmbH, Schrobenhausen |

Abidi Helmi : Programmierung einer C-basierten Ansteuerung für ein 1HE-Rack kompatibles TFT Display samt Touchpad | ||

Supervisor: Gerhard Kramer, Attocube Systems AG, 80539 München |

David Jobst: Porting Interactive Flash Programs to HTLM5 | ||

The old LNTwww contains several Adobe Flash based programs to illustrate complicated topics in communications engineering. As Flash is not supported on many platforms, e.g. iOS, and will likely not be supported in the future at all, we need to migrate those animations to a modern format - otherwise the lntwww will not be usable by many students in future. An HTML5 canvas seems to be the best solution, as it is supported by may browsers including those on mobile phones. The student's task is to set up a framework for porting the programs and port at least one such application. | ||

Supervisor: Karl-Tasnad Kernetzky |

## Forschungspraxis (12 ECTS)

Afghahi Keikavoos: Development of adaptive radio systems for industrial applications | ||

Wireless real-time communication plays an increasingly pivotal role in industrial automation. Next generation high performance wireless technologies have to meet highest demands regarding latency, efficiency and reliability. Further, they have to be smart and adapt to an ever changing radio environment. In this internship you will participate in the research and development of adaptive wireless communication systems for application in the novel field of Industry 4.0. Using a Software Defined Radio (SDR) system you will develop a spectrum sensing procedure, which enables higher efficiency and reliability of wireless communication technologies for industrial applications. This internship will consist of the following tasks: · Getting familiar with the SDR development using USRP (Universal Software Radio Peripheral) and GNU Radio · Development of a spectrum sensing algorithm using the USRP hardware platform · Software development for interferer detection and smart adaptive channel allocation · Creation of a wireless network prototype, which dynamically adapts to a changing radio environment in an industrial scenario | ||

Supervisor: Ginni Khanna, Neda Petreska |

Muhammad Firas Hammosh: Is Online PCA Information-Preserving? | ||

In this research internship, and overview over existing online (i.e., iterative, recursive, etc.) algorithms for Prinicipal Components Analysis (PCA) should be given. We try to find our which (if any) of these algorithms is invertible in the sense that one can reconstruct the original data from only looking at the rotated data. For those algorithms for which this is not possible, the (relative) information loss should be computed. This work thus builds the bridge between PCA given knowledge of the covariance matrix (given-statistics) and PCA given only the sample covariance matrix (given-data). While no information is lost in the former, the information loss in the latter was shown to be substantial. We believe that the information loss of online PCA lies somewhere in between. |
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Supervisor: Bernhard Geiger |

Thomas Wiegart: Evaluation of Non-Binary LDPC codes for Coded Modulation | ||

In this Forschungspraxis, the student reviews the principles of non-binary LDPC codes and will apply it to a coded modulation scenario. In particular, the internship will deal with the efficient implementation of a non-binary LDPC decoder and the evaluation of different codes presented in literature for higher-order modulation. As the Forschungspraxis progresses, it should also focus on the combination with probabilistic amplitude shaping. | ||

Supervisor: Fabian Steiner |

Maximilian Schädler: Monte Carlo Integration for Optical Communication Systems | ||

Modern optical communication sytems suffer from nonlinear fiber effects that are the main limiting factor to increased spectral efficiencies. The split-step Fourier method, which is used to simulate the propagation of an optical signal through fiber, is computationally highly complex, which makes a detailed analysis of the impact of various system parameters on the fiber nonlinearities practically impossible. In this project, Monte Carlo methods are studied in general and applied to optical communication systems. The aim is to find approximate solutions for non-closed-form expressions that describe the impact of the fiber nonlinearities on the signal. | ||

Supervisor: Tobias Fehenberger |

Emna Ben Yacoub: M-Type Approximation of Hidden Markov Models | ||

In this research project, we replace transition and observation probability matrices of hidden Markov models (HMMs) by matrices where each entry is an integer multiple of integer M (i.e., is "M-type"). The problem is an immediate extension of approximating finite-length probability vectors by M-type vectors. The Viterbi algorithm can be used to infer the state sequence from the observation sequence, given that the algorithm has knowledge of the transition and observation matrices. If, instead of the true matrices, the algorithm has knowledge only of their M-type approximations, this will lead to an increase in error probability. We try to find a connection between a probabilistic divergence measure between the true and the M-type model (e.g., Kullback-Leibler divergence rate, matrix norms, etc.) and this increase in error probability. |
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Supervisor: Bernhard Geiger, Rana Ali Amjad |

Venkatesh Satagopan: Error-Correction for Partially Stuck Memory Cells | ||

Supervisor: Antonia Wachter-Zeh |

Anubhab Banerjee: Analysis of Some Code-Based Cryptosystems | ||

Supervisor: Antonia Wachter-Zeh |

Sayantini Majumdar: Sequence Reconstruction for Insertion and Deletion Errors | ||

Supervisor: Andreas Lenz |

Tobias Popetz: Analysis of mobile device communication sequences observed in public networks for reproduction in a simulated network | ||

The communication of a mobile device in a public network is affected by various impairments on the radio channels (e.g. attenuation, multipath reception, Doppler shift). This elicits a specific communication behavior which is recorded in a device log. In this Forschungspraxis the device log is analyzed to identify relevant information for subsequent reproduction of the observed communication behavior under laboratory conditions using simulators for network components and radio channel impairments. | ||

Supervisor: Tobias Prinz, Fa. Rohde & Schwarz GmbH & Co. KG, 81671 München |

## Forschungspraxis (6 ECTS)

Joachim Neu: Evaluation of Spatially Coupled LDPC Codes | ||

The student will review the basics of LDPC convolutional codes and implement a window decoder. Using regular LDPC code ensembles, the student will investigate their performance on the biAWGN channel. If time permits, the work will also consider coded modulation setups involving higher order modulations with probabilistic shaping. | ||

Supervisor: Fabian Steiner |