@inproceedings{LurzMuellerLindneretal., author = {Lurz, Fabian and Mueller, Simon and Lindner, Stefan and Linz, Sarah and Gardill, Markus and Weigel, Robert and K{\"o}lpin, Alexander}, title = {Smart Communication and Relative Localization System for Firefighters and Rescuers}, series = {IEEE International Microwave Symposium, Honolulu, Hawaii, USA}, booktitle = {IEEE International Microwave Symposium, Honolulu, Hawaii, USA}, publisher = {IEEE}, address = {Piscataway, NJ}, isbn = {978-1-5090-6360-4}, doi = {10.1109/MWSYM.2017.8058885}, pages = {1421 -- 1424}, language = {en} } @misc{FuchsGardillLuebkeetal., author = {Fuchs, Jonas and Gardill, Markus and L{\"u}bke, Maximilian and Dubey, Anand and Lurz, Fabian}, title = {A machine learning perspective on automotive radar direction of arrival estimation}, series = {IEEE Access}, volume = {Vol. 10}, journal = {IEEE Access}, issn = {2169-3536}, doi = {10.1109/ACCESS.2022.3141587}, pages = {6775 -- 6797}, language = {en} } @misc{WernerLimanGardill, author = {Werner, Lennart and Liman, Cedric and Gardill, Markus}, title = {High-Fidelity Simulation of a Pico Satellite Link}, series = {IEEE Space Hardware and Radio Conference (SHaRC) 2022, January 16-19, 2022, Las Vegas (USA)}, journal = {IEEE Space Hardware and Radio Conference (SHaRC) 2022, January 16-19, 2022, Las Vegas (USA)}, isbn = {978-1-6654-3475-1}, doi = {10.1109/SHaRC53093.2022.9720016}, pages = {4}, language = {en} } @misc{PetermannClazzerMunarietal., author = {Petermann, Timon and Clazzer, Federico and Munari, Andrea and Gardill, Markus}, title = {Internet of Things via Satellite: A Multiple-Access Performance Study of LoRa and its Enhancements}, series = {11th advanced satellite multimedia systems conference and the 17th signal processing for space communications workshop (ASMS/SPSC), September 6-8, 2022, Graz (Austria)}, journal = {11th advanced satellite multimedia systems conference and the 17th signal processing for space communications workshop (ASMS/SPSC), September 6-8, 2022, Graz (Austria)}, isbn = {978-1-6654-7377-4}, issn = {2326-5949}, doi = {10.1109/ASMS/SPSC55670.2022.9914689}, pages = {1 -- 8}, language = {en} } @misc{GardillPiaseckiJackson, author = {Gardill, Markus and Piasecki, Marie and Jackson, Charlie}, title = {SHaRC 2023}, series = {IEEE Microwave Magazine}, volume = {23}, journal = {IEEE Microwave Magazine}, number = {12}, issn = {1557-9581}, doi = {10.1109/MMM.2022.3203920}, pages = {31 -- 34}, language = {en} } @misc{Gardill, author = {Gardill, Markus}, title = {Radio \& Wireless Week 2023: The Cornerstone of Wireless Connectivity}, series = {IEEE Microwave Magazine}, volume = {23}, journal = {IEEE Microwave Magazine}, number = {12}, issn = {1557-9581}, doi = {10.1109/MMM.2022.3203952}, pages = {24 -- 25}, language = {en} } @misc{GardillMaune, author = {Gardill, Markus and Maune, Holger}, title = {Moving Toward an MTT-S Payload in Space: Progress and Status of the MTT-Sat Challenge}, series = {IEEE Microwave Magazine}, volume = {23}, journal = {IEEE Microwave Magazine}, number = {10}, issn = {1557-9581}, doi = {10.1109/MMM.2022.3188125}, pages = {59 -- 67}, language = {en} } @misc{GarbeDietlGardilletal., author = {Garbe, Daniel and Dietl, Guido and Gardill, Markus and Schilling, Klaus}, title = {Minimising Communication Efforts in Self-Organised Relative Attitude Control for Formation Flight Scenarios Using Direction of Arrival Methods}, series = {IAF Space Communications And Navigation Symposium - Advances In Space-Based Communication Technologies, Paris (France), 2022}, journal = {IAF Space Communications And Navigation Symposium - Advances In Space-Based Communication Technologies, Paris (France), 2022}, pages = {105}, language = {en} } @misc{AdlerHeiseGarbeetal., author = {Adler, Antonius and Heise, F. and Garbe, Daniel and Schilling, Klaus and Gardill, Markus}, title = {Relative Attitude Estimation via Radio Frequency Links - Feasibility Study Based on High-Fidelity Co-Simulation}, series = {IAF Space Communications And Navigation Symposium - Advances In Space-Based Communication Technologies, Paris (France), 2022}, journal = {IAF Space Communications And Navigation Symposium - Advances In Space-Based Communication Technologies, Paris (France), 2022}, pages = {107}, language = {en} } @misc{Gardill, author = {Gardill, Markus}, title = {TC-27 Connected and Autonomous Systems Committee—Connected and Autonomous Systems: Jointly Moving Toward the Future—2022}, series = {IEEE Microwave Magazine}, volume = {23}, journal = {IEEE Microwave Magazine}, number = {11}, issn = {1557-9581}, pages = {130 -- 131}, language = {en} } @misc{GardillPearsonScharnagletal., author = {Gardill, Markus and Pearson, Dominik and Scharnagl, Julian and Schilling, Klaus}, title = {Towards Wireless Ranging and Synchronization using CubeSat Software-Defined Radio Subsystems}, series = {IEEE Space Hardware and Radio Conference, Las Vegas (NV, USA), 2023}, journal = {IEEE Space Hardware and Radio Conference, Las Vegas (NV, USA), 2023}, doi = {10.48550/arXiv.2212.00355}, pages = {4}, language = {en} } @misc{GardillTandon, author = {Gardill, Markus and Tandon, Tushar}, title = {A Radar Kit for Hands-On Distance-Learning}, series = {European Microwave Week 2021, Focussed Session on on Teaching Methods for Microwave Engineering, April 2-7, 2022, London (UK)}, journal = {European Microwave Week 2021, Focussed Session on on Teaching Methods for Microwave Engineering, April 2-7, 2022, London (UK)}, publisher = {IEEE}, address = {Piscataway, NJ}, isbn = {978-2-87487-063-7}, doi = {10.23919/EuMC50147.2022.10050230}, pages = {13 -- 16}, language = {en} } @misc{KahlertFeiTebrueggeetal., author = {Kahlert, Moritz and Fei, Tai and Tebruegge, Claas and Gardill, Markus}, title = {An Improved Stepped-Frequency PMCW Waveform for Automotive Radar Applications}, series = {IEEE 15th German Microwave Conference (GeMiC), 11-13 March 2024, Duisburg, Germany}, journal = {IEEE 15th German Microwave Conference (GeMiC), 11-13 March 2024, Duisburg, Germany}, issn = {2167-8022}, doi = {10.23919/GeMiC59120.2024.10485360}, pages = {4}, abstract = {In phase-modulated continuous wave (PMCW) radar systems, fine range resolution typically requires high instantaneous bandwidths, necessitating fast-sampling analog-to-digital converters (ADCs). However, these ADCs are expensive and power-consuming. Consequently, due to their affordable hardware implementation, today's automotive radar systems still mainly employ analog frequency-modulated continuous wave (FMCW) waveforms. A larger bandwidth without requiring fast-sampling ADCs can also be synthesized by transmitting consecutive pulses in a coherent processing interval (CPI) at incremented carrier frequencies. To enable PMCW with low-data-rate ADCs, this paper proposes an improved stepped-frequency PMCW (SF-PMCW) waveform and evaluates its performance against a stepped-frequency FMCW (SF-FMCW) radar system in a simulated environment. The results indicate that the proposed SF- PMCW waveform can yield superior target detection capabilities with comparable system parameters.}, language = {en} } @misc{KahlertFeiWildenetal., author = {Kahlert, Moritz and Fei, Tai and Wilden, Norwin and Tebruegge, Claas and Gardill, Markus}, title = {MLS-based Transmitter Orthogonality Analysis in MIMO-PMCW Automotive Radar Systems}, series = {IEEE 13rd Sensor Array and Multichannel Signal Processing Workshop (SAM), 08-11 July 2024, Corvallis, OR, USA}, journal = {IEEE 13rd Sensor Array and Multichannel Signal Processing Workshop (SAM), 08-11 July 2024, Corvallis, OR, USA}, doi = {10.1109/SAM60225.2024.10636563}, pages = {5}, abstract = {Precise angular measurements are essential for au-tomated driving functions, and the antenna aperture and the number of antennas in a radar system determine the angle measuring ability. Recently, phase-modulated continuous wave (PMCW) technology has been integrated into multiple input multiple output (MIMO) systems, enabling a larger antenna aperture by multiplexing multiple transmitter antennas simul-taneously. In this work, we evaluate the performance of a large-scale MIMO-PMCW radar system in simulated scenarios using the peak-sidelobe level (PSL) after range-Doppler processing as a performance metric. The results show that the sequence length and the relative velocity in radar systems strongly influence the detection performance.}, language = {en} } @misc{KahlertFeiTebrueggeetal., author = {Kahlert, Moritz and Fei, Tai and Tebruegge, Claas and Gardill, Markus}, title = {Range Migration Compensation for a PMCW Automotive Radar System}, series = {21st European Radar Conference (EuRAD), 04 November 2024, Paris, France}, journal = {21st European Radar Conference (EuRAD), 04 November 2024, Paris, France}, doi = {10.23919/EuRAD61604.2024.10734955}, pages = {196 -- 199}, abstract = {Fine range and Doppler resolutions are desirable in automotive radar systems to estimate target properties accurately. However, targets detected by radar systems can suffer from range migration, which is caused by the relative movement of targets during the coherent processing interval (CPI). Range migration results in energy dispersion across multiple cells in the range-Doppler domain. This dispersion leads to a reduced signal-to-noise ratio (SNR) and an increased risk of masking weak targets in adjacent cells. To address this issue, we present a range migration compensation method for phase-modulated continuous wave (PMCW) radar systems. The feasibility is investigated in a simulated environment. The results show that the approach focuses target energy into a single range-Doppler cell, resulting in an increased SNR and improved target detection.}, language = {en} } @misc{KahlertFeiTebrueggeetal., author = {Kahlert, Moritz and Fei, Tai and Tebruegge, Claas and Gardill, Markus}, title = {Stepped-frequency PMCW-radar modulation scheme for automotive applications}, series = {IEEE Topical Conference on Wireless Sensors and Sensor Networks (WiSNet), 21-24 January 2024, San Antonio, TX, USA}, journal = {IEEE Topical Conference on Wireless Sensors and Sensor Networks (WiSNet), 21-24 January 2024, San Antonio, TX, USA}, isbn = {979-8-3503-2982-7}, issn = {2473-4624}, doi = {10.1109/WiSNeT59910.2024.10438643}, pages = {4}, abstract = {For digital modulation schemes like phase-modulated continuous wave (PMCW) and orthogonal frequency division multiplexing (OFDM), the baseband bandwidth equals the radio frequency bandwidth. High bandwidth is necessary for achieving fine-range resolution. While high sampling rates require expensive analog-to-digital converters (ADCs) at the receiver, low-cost radar solutions are preferred for automotive radar systems. In prior research, a stepped-frequency OFDM modulation scheme was proposed to achieve fine-range resolution while reducing the sampling rates of the ADCs. Motivated by this, we propose a stepped-frequency PMCW modulation scheme to obtain highly separable range-Doppler measurements at reduced sampling rates. For this purpose, the carrier frequency of successively transmitted sequences is varied, resulting in a range-dependent frequency shift along the slow-time domain. The modulation scheme is presented analytically, and its feasibility is investigated in a simulated environment.}, language = {en} } @misc{FeiMukhopadhyayDaCostaetal., author = {Fei, Tai and Mukhopadhyay, Subhas and Da Costa, Jo{\~a}o Paulo Javidi and Gardill, Markus and Liu, Shengheng and Roychaudhuri, Chirasree and Lan, Lan and Demitri, Nevine}, title = {Guest editorial special issue on smartness and robustness of spatial environment perception in automated systems}, series = {IEEE Sensors Journal}, volume = {24}, journal = {IEEE Sensors Journal}, number = {14}, issn = {1558-1748}, doi = {10.1109/JSEN.2024.3409137}, pages = {21800 -- 21800}, abstract = {As the curtains close on this special issue dedicated to advanced sensor research, we reflect on the critical role sensor technology plays in the future of automation. Throughout this issue, we have explored significant advancements and ongoing challenges in developing intelligent, resilient automated systems. A key theme is the vital need for smarter, more robust sensing systems. Modern sensors, now more adaptable, adjust their operations based on external changes, crucial for maximizing automation in varied real-world situations. Efforts to enhance sensor robustness have produced improvements in performance in extreme conditions, cybersecurity, cost-effective solutions, and flexible system requirements while preserving performance. The addition of self-monitoring and calibration features allows for continuous refinement of sensor accuracy and rapid problem detection, boosting system reliability. The capacity for seamlessly integrating alternative technologies when specific sensors fail further strengthens system resilience. This issue includes 33 manuscripts selected from 65 submissions, exploring these diverse aspects.}, language = {en} } @misc{KahlertXuFeietal., author = {Kahlert, Moritz and Xu, Lifan and Fei, Tai and Gardill, Markus and Sun, Shunqiao}, title = {High-resolution DOA estimation using single-snapshot music for automotive radar with Mixed-ADC allocations}, series = {IEEE 13rd Sensor Array and Multichannel Signal Processing Workshop (SAM), 08-11July 2024, Corvallis, OR, USA}, journal = {IEEE 13rd Sensor Array and Multichannel Signal Processing Workshop (SAM), 08-11July 2024, Corvallis, OR, USA}, isbn = {979-8-3503-4481-3}, issn = {2151-870X}, doi = {10.1109/SAM60225.2024.10636418}, pages = {5}, abstract = {Fine direction of arrival (DOA) estimations are required for accurate target detections in automotive radar systems. To address this issue, most spectral estimation methods assume many snapshots of measurements. However, due to the dynamic nature of automotive scenarios, methods using multiple snapshots are impractical for DOA estimation in automotive radars. Furthermore, to relax the hardware requirements on modern automotive radar systems, mixed-analog-to-digital converter (ADC) allocations, i.e., the coexistence of 1-bit and high-resolution ADCs, have gained more attention recently. In this work, we introduce a high-resolution DOA estimation approach based on single-snapshot multiple signal classification (MUSIC) estimation and evaluate the performance with various ADC allocations. The results show that mixed-ADC allocations can perform comparably to high-resolution ADC allocations.}, language = {en} } @misc{KahlertFeiTebrueggeetal., author = {Kahlert, Moritz and Fei, Tai and Tebruegge, Claas and Gardill, Markus}, title = {Doppler Ambiguity Resolution for a PMCW Automotive Radar System}, series = {20th European Radar Conference (EuRAD), 20-22 September 2023, Berlin (Germany)}, journal = {20th European Radar Conference (EuRAD), 20-22 September 2023, Berlin (Germany)}, publisher = {IEEE}, isbn = {978-2-87487-074-3}, doi = {10.23919/EuRAD58043.2023.10289445}, pages = {73 -- 76}, language = {en} } @misc{KahlertFeiHirneretal., author = {Kahlert, Moritz and Fei, Tai and Hirner, Junus and Tebruegge, Claas and Gardill, Markus}, title = {Multi-Target Doppler Ambiguity Identification for a PMCW Automotive Radar System}, series = {31st European Signal Processing Conference (EUSIPCO), 04-08 September 2023, Helsinki (Finland)}, journal = {31st European Signal Processing Conference (EUSIPCO), 04-08 September 2023, Helsinki (Finland)}, publisher = {IEEE}, isbn = {978-9-4645-9360-0}, issn = {2076-1465}, doi = {10.23919/EUSIPCO58844.2023.10290009}, pages = {795 -- 799}, language = {en} }