Theses
Signal Strength-Based Distance Estimation in Multipath Environments Based on Frequency Hopping
Tasks:
- Simulation of received signal strength in multipath propagation environments with different frequencies
- Implementation of a distance estimation algorithm via a communication interface with integrated frequency hopping (e.g., Bluetooth)
- Evaluation and comparison of simulation results with experimentally measured data
Supervisor:
Further Dynamic Wireless Meshed Network Topics
- Radio Based Localisation of Nodes in a Drone Swarm Network
- Decentralised Synchronisation of Nodes in a Drone Swarm Network
- Design of a LoRa Communication System with Adalm Pluto and Julia
Effects of Space Diversity in the 3GPP Satellite Channel Model
Context
- The UWE-5 project shall use nanosatellites to relay traffic between the Würzburg and Cottbus ground stations
- 3GPP (the standards body responsible LTE, 5G, ...) has created a model of a satellite to user equipment (UE, the mobile device) channel - and while with UWE-5 no satellite-to-UE communication will be attempted, it still serves as an indicator for the future
Tasks
- Understand and implement the 3GPP channel model and a diversity scheme (e.g. Alamouti) in a simulation
- Evaluate the connection (e.g. coded BER or mutual information) with and without diversity - does it provide an improvement?
Supervision
Prof. Dr. Guido Dietl and Philip Bergmann
Investigation of a 5G Communications Link with Satellite Backhaul
Context
- UWE-5 shall relay 5G traffic between Würzburg and Cottbus
- The satellites shall also be integrated into the 5G network and be addressable from the user equipment (e.g. phones)
Tasks
- Using an existing 5G framework (srsRAN, OpenAirInterface), implement a virtual 5G deployment
- Identify metrics for determining the quality of service of a 5G-backed connection
- Evaluate the effects of satellite backhauling (noticable bit error rate, chageing round trip time and error propability) on the user experience
Supervision
Prof. Dr. Guido Dietl and Philip Bergmann
Implementation and Evaluation of a 5G to Satellite Network Function
Context
- UWE-5 shall relay 5G traffic between Würzburg and Cottbus
- The different components in an 5G deployment communicate with IP-based protocols
Tasks
- Design and implement a network function that translates 5G traffic into a more efficient representation for transfer via satellite
- The ideal outcome is a simulation with a proof-of-concept of the network function
Supervision
Info 3 (Prof. Dr. Tobias Hoßfeld, Dr. Stefan Geißler, and Simon Raffeck), Info 7 SCRS (Prof. Dr. Guido Dietl and Philip Bergmann) and Info 8 ESSEO (Prof. Dr. Marco Schmidt)
Comparison of LoRa(WAN), NB-IoT and LTE-m for ISL and Space-to-Ground for CubeSats
Context
- Multiple competing Low Power Wide Area Network (LPWAN) standards exist, mainly designed for terrestrial IoT applications
Tasks
- Survey of existing standards and their design criteria (what was optimized for, trade-offs, ...)
- Which ones would be suitable for ISL and Space-Ground communications?
- How much of the standard can be used in a typical university CubeSat mission?
Supervision
Prof. Dr. Guido Dietl and Philip Bergmann
Investigation of Different Modulation Schemes for Communications over a Satellite-to-Ground Link in the Ku-Band
Context
- UWE-5 will carry an Software Defined Radio (SDR) and some COTS transceivers, which will be up-and downconverted to and from K/Ka band
- An SDR allows lots of flexibility, therefore many choices are available
- The COTS transceivers currently planned are the SX1280 (LoRa, FLRC and FSK)
Tasks
- Investigate different modulation schemes possible with the SDR
- Compare the SDR and COTS transceiver schemes in simulation or theoretically (data rate, bit error rate, energy requirements, ...)
Supervision
Prof. Dr. Guido Dietl and Philip Bergmann
Energy-Efficient Programming of Embedded Software Defined Radios
Context
- UWE-5 will carry and Software Defined Radio (SDR) and some COTS transceivers
- An SDR trades flexibility for energy efficiency
- Energy is always at a premium on satellites
Tasks
- Research energy-efficient digital signal processing programming techniques
- Compare different implementations (COTS, SDR with stock/own implementation, FPGA?)
Supervision
Prof. Dr. Guido Dietl and Philip Bergmann
On the way to LoRa: Implementation and Evaluation of a Frequency Shift Chirp Modulation (FSCM) scheme
Context
- FSCM is the waveform also used by LoRa: The offset from a base chirp determines the symbol
Tasks
- Implement modulation and demodulation for SDRs with e.g. Julia - an "offline" (i.e. not live) approach is fine and allows gaining a thorough understanding of digital signal processing and practical low-level experience
- In Contrast with LoRa the "higher level" features of the PHY (interleaving, coding) can be left out, but whitening probably needs to be implemented
- Evaluation can e.g. be different methods for synchronization, compatibility of your demodulaor with ISL / Doppler shift, etc.
Supervision
Prof. Dr. Guido Dietl and Philip Bergmann
Further topics
- If you have own ideas, please reach out! We are open to ideas that are modifications of mentioned topics or ideas that are not explicitly listed here.
High Coverage Satellite Networks Based on 5G and Beyond (in cooperation with LS 3)
Tasks:
- Literature research on satellite networks for high coverage with a focus on 5G/6G solutions
- Feasibility study of connecting 5G campus network to UWE satellites or a satellite network in general
- Implementation of communications link between 5G campus network and a UWE satellite
- Comparison to alternative communication systems like, e.g., LoRa
Supervisor:
Prof. Dr. Guido Dietl and Prof. Dr. Tobias Hoßfeld
Energy Efficient Scheduling and Resource Allocation in Integrated Satellite-Terrestrial Networks (ISTN)
Tasks:
- Problem Formulation: scheduling and resource allocation minimising transmit power in the downlink
- Optimisation and Evaluation of Power Savings
- Paper: “LEO-to-User Assignment and Resource Allocation for Uplink Transmit Power Minimization, Hung Nguyen-Kha, Vu Nguyen Ha, Eva Lagunas, Symeon Chatzinotas and Grotz Joel, WSA & SCC 2023”
Supervisor:
Simultaneous Estimation of the Doppler Frequencies of a Satellite Constellation
Tasks:
- Estimation of the Doppler frequency of the satellite-to-ground link of one satellite which is based on OFDM modulation
- Performance comparison to other modulations
- Simultaneous estimation of the Doppler frequencies of the satellite-to-ground links of a constellation
Supervisor:
Further Satellite Network Topics
- Routing in LEO Satellite Networks with a Huge Number of Satellites
- Software Defined Satellite Networks
- Optimisation of Satellite Constellations for 5G and Beyond-5G Communications
- Massive Multiple-Input Multiple-Output Satellite Communications
Implementation of a PPM based Optical Communications System Towards the Realization of a Drone-to-Drone Link
Tasks:
- Implementation of a free-space optical communications link based on Pulse-Position-Modulation (PPM)
- Realisation of an optical Drone-to-Ground communications link
- Realisation of an optical Drone-to-Drone communications link (if time)
- Performance analysis
Supervisor:
Free-Space Optical Communications with Intelligent Reflecting Surfaces (IRS)
Tasks:
- Basic paper: Jamali et al. (2021)
- Applications:
- V2V communications
- drone network
- satellite network
- Simulation or experimental set-up
Supervisor:
Comparison of LDPC and Polar Codes for Fault Tolerant Quantum Communications
Tasks:
- Implementation of quantum Low Density Parity Check (LDPC) and quantum polar codes
- Implementation of different decoding algorithms [see, e.g., Chandra2023]
- Simulation of an erroneous discrete-variable and/or continuous-variable quantum communications link using these codes for error correction
- Performance analysis
Supervisor:
Analysis of the Quantum Error Correction Codes Based on Different Error Models
Tasks:
- Define error models for typical errors of quantum computers
- Investigate Shor code, Steane code and Laflamme code for these error models
- Comparison of these traditional codes with state-of-the-art codes
Supervisor:
Comparison of Classical and Quantum Error Correction Coding for Information Reconciliation of QKD
Tasks:
- Noise and interference model
- Literature research on information reconciliation methods
- Simulations of QKD with classical and quantum error correction coding
- Numerical comparison
Supervisor:
Investigation of Entanglement Distillation Protocols in Quantum Networks
Tasks:
- Modelling of different quantum networks and the disentanglement within
- Analysis of entanglement distillation protocols wihtin such networks
- Simulation and investigation of optimal distillation approaches
Supervisor:
Analysis of Quantum Network Routing Schemes
Tasks:
- Investigation of different routing strategies within quantum networks
- Modelling of entanglement distribution within quantum networks
- Construction of a quantum routing alogrithm
- Simulation based evaluation of the routing algorithm
Supervisor:
Routing of Entangled Quantum States in a Quantum Network for Increased Security Against Denial-of-Service Attacks
Tasks:
- Analysis of Denial-of-Service attack models for quantum networks
- Modelling of the influence of repeaters within quantum networks
- Simulation on the security influence of such routing within quantum networks for entanglement based QKD
Supervisor:
Investigation of Possible Attack Methods on Quantum Channels Based on Quantum Effects
Tasks:
- Investigation on Quantum Key Distribution (QKD) security proofs.
- Consideration of these safety proofs taking into account real imperfections within the quantum devices.
Supervisor:
Continuous-Variable Quantum Key Distribution (CV-QKD) Based on Higher Modulation Schemes
Tasks:
- Combine CV-QKD with higher modulation schemes
- Performance analysis (risk and key rate)
- Comparison to state-of-the-art
Supervisor:
Marcel Kokorsch and Prof. Dr. Guido Dietl
Clock Synchronisation for Quantum Sensing Based on Squeezed Coherent States
Tasks:
- Quantum sensing is based on squeezed light which decreases the measurement variance at some time instances.
- For quantum sensing to work, this time instances need to be determined before sampling.
- Development and investigation of a clock synchronisation algorithm for quantum sensing
Supervisor:
Further Quantum Communications Topics
- Synchronisation of a quantum network
- Channel estimation and prediction of a dynamic optical satellite-to-ground link for the correction of polarisation errors
- Comparison of DV and CV systems for the application in satellite networks
Investigation of MOXZ for Joint Communications and Sensing
Tasks:
- Literature recherche on exisiting schemes (MOXZ and alternatives)
- Numerical analysis
Supervisor:
Investigation of Orthogonal Time Frequency Space (OTFS) Modulation for Joint Communications and Sensing
Tasks:
- Implementation of a simulation environment in Julia
- Comparison of OTFS and OFDM for joint communications and sensing with respect to communications (e.g., spectral efficiency) and sensing (e.g., Cramer-Rao bound) performance
- If time: investigation of Orthogonal Time Sequency Multiplexing (OTSM) modulation and comparison to OTFS and OFDM
- more details on: https://ecse.monash.edu/staff/eviterbo/OTFS-VTC18/index.html
Supervisor:
Hybrid Lidar for Sensing and Communications (in cooperation with LS 17)
Tasks:
- Reusing lidar for communications
- classical one- and two-way, e.g., car-to-car
- Quantum Key Distribution (QKD)
- Investigation of different modulation and QKD schemes
- Proof of concept and performance evaluation
Supervisor:
Prof. Dr. Guido Dietl and Prof. Dr. Andreas Nüchter
Radio Based Direction Finding and Tracking for Space Rendezvous (in cooperation with LS 8)
- Investigation of two possible strategies:
- fixed beams and direction finding/tracking via attitude control
- fixed attitude and direction finding/tracking via beamforming (antenna array)
- Simulative performance evaluation
- Proof of concept based on the usage of drones
Supervisor:
Further Radar Signal Processing Topics
- System Design of Joint Radar Sensing and Wireless Communication
- Design and Simulative Investigation of a MIMO-OFDM-Radar
Template
A template and some hints for writing a good thesis are available on the IfI GitLab: https://gitlab2.informatik.uni-wuerzburg.de/scrs/templates/latex_thesis
