FG Theoretische Grundlagen der Kommunikationstechnik

18 Items

Recent Submissions
Information Bottleneck for a Rayleigh Fading MIMO Channel with an Oblivious Relay

Xu, Hao ; Yang, Tianyu ; Caire, Giuseppe ; Shamai Shitz, Shlomo (2021-04-08)

This paper considers the information bottleneck (IB) problem of a Rayleigh fading multiple-input multiple-out (MIMO) channel with an oblivious relay. The relay is constrained to operating without knowledge of the codebooks, i.e., it performs oblivious processing. Moreover, due to the bottleneck constraint, it is impossible for the relay to inform the destination node of the perfect channel stat...

Sparse recovery based grant-free random access for massive machine-type communication

Fengler, Alexander (2021)

This dissertation treats a recently introduced modern random access protocol known as unsourced random access (U-RA). This protocol belongs to the family of grant-free random access protocols which, in contrast to the established grant-based protocols of current mobile communication standards, do not rely on an initial access phase, in which the active devices identify themselves and await the ...

An Optimality Summary: Secret Key Agreement with Physical Unclonable Functions

Günlü, Onur ; Schaefer, Rafael (2020-12-24)

We address security and privacy problems for digital devices and biometrics from an information-theoretic optimality perspective to conduct authentication, message encryption/decryption, identification or secure and private computations by using a secret key. A physical unclonable function (PUF) provides local security to digital devices and this review gives the most relevant summary for infor...

Cache-Aided General Linear Function Retrieval

Wan, Kai ; Sun, Hua ; Ji, Mingyue ; Tuninetti, Daniela ; Caire, Giuseppe (2020-12-26)

Coded Caching, proposed by Maddah-Ali and Niesen (MAN), has the potential to reduce network traffic by pre-storing content in the users’ local memories when the network is underutilized and transmitting coded multicast messages that simultaneously benefit many users at once during peak-hour times. This paper considers the linear function retrieval version of the original coded caching setting, ...

Skew Convolutional Codes

Sidorenko, Vladimir ; Li, Wenhui ; Günlü, Onur ; Kramer, Gerhard (2020-12-02)

A new class of convolutional codes, called skew convolutional codes, that extends the class of classical fixed convolutional codes, is proposed. Skew convolutional codes can be represented as periodic time-varying convolutional codes but have a description as compact as fixed convolutional codes. Designs of generator and parity check matrices, encoders, and code trellises for skew convolutional...

Coded caching over realistic and scalable wireless networks

Bayat, Mozhgan (2020)

The coded caching scheme proposed by Maddah-Ali and Niesen (MAN) is designed to reduce peak hours traffic by partially prefetching the files in end users' cache memory in low traffic hours and sending the requested files through multicast messages. This scheme was proved to be optimal under the constraint of uncoded prefetching and was originally proposed for a so-called single bottleneck link ...

Stealthy Secret Key Generation

Lin, Pin-Hsun ; Janda, Carsten R. ; Jorswieck, Eduard A. ; Schaefer, Rafael F. (2020-06-18)

In order to make a warden, Willie, unaware of the existence of meaningful communications, there have been different schemes proposed including covert and stealth communications. When legitimate users have no channel advantage over Willie, the legitimate users may need additional secret keys to confuse Willie, if the stealth or covert communication is still possible. However, secret key generati...

Millimeter wave wireless communication: initial acquisition, data communication and relay network investigation

Song, Xiaoshen (2020)

Wireless communication has become an important part of our daily lives. In the past decades, the phenomenal increasing demand for mobile wireless data services has been pushing both industry and academia to move to millimeter wave (mmWave) frequencies (30-300GHz) for the next generation (5G) mobile communication. The main motivation for mmWave communication is the unprecedented massive bandwidt...

Design and Implementation of centralized signal processing low latency massive MIMO SDR systems

Benzin, Andreas Florian (2020)

The following thesis presents a full digital massive MIMO (multiple-input and multiple-output) sub-6GHz cellular base station design and implementation which is capable of performing low latency zero forcing precoding on a single central field programmable gate array (FPGA) unit. The central signal processing single FPGA architecture reduces system size, complexity, power consumption, algorithm...

Sensor Artificial Intelligence and its Application to Space Systems - A White Paper

Börner, Anko ; Heinz-Wilhelm, Hübers ; Kao, Odej ; Schmidt, Florian ; Becker, Sören ; Denzler, Joachim ; Matolin, Daniel ; Haber, David ; Lucia, Sergio ; Samek, Wojciech ; Triebel, Rudolph ; Eichstädt, Sascha ; Biessmann, Felix ; Kruspe, Anna ; Jung, Peter ; Kok, Manon ; Gallego, Guillermo ; Berger, Ralf (2020-06)

Information and communication technologies have accompanied our everyday life for years. A steadily increasing number of computers, cameras, mobile devices, etc. generate more and more data, but at the same time we realize that the data can only partially be analyzed with classical approaches. The research and development of methods based on artificial intelligence (AI) made enormous progress i...

Secure and Reliable Key Agreement with Physical Unclonable Functions

Günlü, Onur ; Kernetzky, Tasnad ; İşcan, Onurcan ; Sidorenko, Vladimir ; Kramer, Gerhard ; Schaefer, Rafael (2018-05-03)

Different transforms used in binding a secret key to correlated physical-identifier outputs are compared. Decorrelation efficiency is the metric used to determine transforms that give highly-uncorrelated outputs. Scalar quantizers are applied to transform outputs to extract uniformly distributed bit sequences to which secret keys are bound. A set of transforms that perform well in terms of the ...

Efficient Algorithms for Coded Multicasting in Heterogeneous Caching Networks

Vettigli, Giuseppe ; Ji, Mingyue ; Shanmugam, Karthikeyan ; Llorca, Jaime ; Tulino, Antonia M. ; Caire, Giuseppe (2019-03-25)

Coded multicasting has been shown to be a promising approach to significantly improve the performance of content delivery networks with multiple caches downstream of a common multicast link. However, the schemes that have been shown to achieve order-optimal performance require content items to be partitioned into several packets that grows exponentially with the number of caches, leading to cod...

Robust Biometric Authentication from an Information Theoretic Perspective

Grigorescu, Andrea ; Boche, Holger ; Schaefer, Rafael F. (2017-09-09)

Robust biometric authentication is studied from an information theoretic perspective. Compound sources are used to account for uncertainty in the knowledge of the source statistics and are further used to model certain attack classes. It is shown that authentication is robust against source uncertainty and a special class of attacks under the strong secrecy condition. A single-letter characteri...

Artificial Noise-Aided Physical Layer Security in Underlay Cognitive Massive MIMO Systems with Pilot Contamination

Al-Hraishawi, Hayder ; Baduge, Gayan Amarasuriya Aruma ; Schaefer, Rafael F. (2017-07-10)

In this paper, a secure communication model for cognitive multi-user massive multiple-input multiple-output (MIMO) systems with underlay spectrum sharing is investigated. A secondary (cognitive) multi-user massive MIMO system is operated by using underlay spectrum sharing within a primary (licensed) multi-user massive MIMO system. A passive multi-antenna eavesdropper is assumed to be eavesdropp...

Derandomizing Compressed Sensing With Combinatorial Design

Jung, Peter ; Kueng, Richard ; Mixon, Dustin G. (2019-06-06)

Compressed sensing is the art of effectively reconstructing structured n-dimensional vectors from substantially fewer measurements than naively anticipated. A plethora of analytical reconstruction guarantees support this credo. The strongest among them are based on deep results from large-dimensional probability theory and require a considerable amount of randomness in the measurement design. H...

Simultaneous Structures in Convex Signal Recovery—Revisiting the Convex Combination of Norms

Kliesch, Martin ; Szarek, Stanislaw J. ; Jung, Peter (2019-05-28)

In compressed sensing one uses known structures of otherwise unknown signals to recover them from as few linear observations as possible. The structure comes in form of some compressibility including different notions of sparsity and low rankness. In many cases convex relaxations allow to efficiently solve the inverse problems using standard convex solvers at almost-optimal sampling rates. A st...

Efficient data delivery in 5G mobile communication networks

Li, Yilin (2019)

Die ständig zunehmende Verbreitung intelligenter Geräten, die Einführung neuer benutzerorientierter unternehmenskritischer Anwendungen, sowie ein exponentieller Anstieg der Nachfrage und Nutzung mobiler Daten, belasten die bestehenden Mobilfunknetze erheblich. Tatsächlich muss der Mobilfunk der fünften Generation (5G) ein Paradigmenwechsel sein, der sehr hohe Trägerfrequenzen mit großen Bandbre...

Autonomous algorithms for centralized and distributed interference coordination: a virtual layer-based approach

Kasparick, Martin ; Wunder, Gerhard (2014)

Interference mitigation techniques are essential for improving the performance of interference limited wireless networks. In this paper, we introduce novel interference mitigation schemes for wireless cellular networks with space division multiple access (SDMA). The schemes are based on a virtual layer that captures and simplifies the complicated interference situation in the network and that i...