TY - GEN A1 - Erhardt, Stefan A1 - Tost, Frank A1 - Lurz, Fabian A1 - Weigel, Robert A1 - Kölpin, Alexander T1 - Design and Assembly of Miniature Long-Term Trackers for Migrating Bats T2 - 2020 German Microwave Conference : March 9-11, 2020, Cottbus, Germany Y1 - 2020 SN - 978-398203971-8 SP - 144 EP - 147 PB - IEEE CY - Piscataway, NJ ER - TY - GEN A1 - Frank, Martin A1 - Lurz, Fabian A1 - Weigel, Robert A1 - Kölpin, Alexander T1 - Universal low-cost transmitarray antenna design at 61 GHz for beam steering with different feed antennas T2 - WSA 2020 : 24th International ITG Workshop on Smart Antennas : February 18-20, 2020, Hamburg, Germany Y1 - 2020 SN - 978-380075200-3 PB - VDE VERLAG GmbH CY - Berlin ; Offenbach ER - TY - GEN A1 - Dorn, Christian A1 - Erhardt, Stefan A1 - Weigel, Robert A1 - Kölpin, Alexander A1 - Lurz, Fabian T1 - Low-profile and low-cost transmitarray antenna at 122 GHz based on unit-cells with 1-bit phase resolution T2 - IEEE Topical Conference on Wireless Sensors and Sensor Networks,26-29 Jan. 2020, San Antonio, TX, USA Y1 - 2020 SN - 978-172813355-3 U6 - https://doi.org/10.1109/WiSNeT46826.2020.9037602 ER - TY - GEN A1 - Michler, Fabian A1 - Shi, Kilin A1 - Schellenberger, Sven A1 - Scheiner, Benedict A1 - Lurz, Fabian A1 - Weigel, Robert A1 - Kölpin, Alexander T1 - On the impact of system nonlinearities in continuous-wave radar systems for vital parameter sensing T2 - IEEE Topical Conference on Wireless Sensors and Sensor Networks, 26-29 Jan. 2020, San Antonio, TX, USA Y1 - 2020 SN - 978-172813355-3 U6 - https://doi.org/10.1109/WiSNeT46826.2020.9037603 ER - TY - GEN A1 - Heining, Simon A1 - Michler, Fabian A1 - Scheiner, Benedict A1 - Hassan, Emadeldeen A1 - Kölpin, Alexander A1 - Weigel, Robert A1 - Lurz, Fabian T1 - An Ultra Broadband Multi-Tone Six-Port Radar for Distance Measurements in K-Band Waveguides T2 - IEEE Radio and Wireless Symposium 2020,26-29 Jan. 2020, San Antonio, TX, USA Y1 - 2020 SN - 978-1-7281-1120-9 SN - 978-1-7281-1119-3 U6 - https://doi.org/10.1109/RWS45077.2020.9050025 ER - TY - GEN A1 - Erhardt, Stefan A1 - Koller, Josef A1 - Lurz, Fabian A1 - Weigel, Robert A1 - Kölpin, Alexander T1 - An Automatic Detection and Data Downlink System for Miniature Bat Loggers T2 - IEEE Radio and Wireless Symposium, 26-29 Jan. 2020, San Antonio, TX, USA Y1 - 2020 SN - 978-172811120-9 U6 - https://doi.org/10.1109/RWS45077.2020.9050051 SN - 2164-2958 SP - 247 EP - 250 ER - TY - GEN A1 - Werner, Lennart A1 - Liman, Cedric A1 - Gardill, Markus T1 - High-Fidelity Simulation of a Pico Satellite Link T2 - IEEE Space Hardware and Radio Conference (SHaRC) 2022, January 16-19, 2022, Las Vegas (USA) Y1 - 2022 SN - 978-1-6654-3475-1 SN - 978-1-6654-3474-4 U6 - https://doi.org/10.1109/SHaRC53093.2022.9720016 ER - TY - GEN A1 - Petermann, Timon A1 - Clazzer, Federico A1 - Munari, Andrea A1 - Gardill, Markus T1 - Internet of Things via Satellite: A Multiple-Access Performance Study of LoRa and its Enhancements T2 - 11th advanced satellite multimedia systems conference and the 17th signal processing for space communications workshop (ASMS/SPSC), September 6-8, 2022, Graz (Austria) Y1 - 2022 SN - 978-1-6654-7377-4 SN - 978-1-6654-7378-1 U6 - https://doi.org/10.1109/ASMS/SPSC55670.2022.9914689 SN - 2326-5949 SN - 2329-7093 SP - 1 EP - 8 ER - TY - GEN A1 - Gardill, Markus A1 - Tandon, Tushar T1 - A Radar Kit for Hands-On Distance-Learning T2 - European Microwave Week 2021, Focussed Session on on Teaching Methods for Microwave Engineering, April 2-7, 2022, London (UK) Y1 - 2022 SN - 978-2-87487-063-7 U6 - https://doi.org/10.23919/EuMC50147.2022.10050230 SP - 13 EP - 16 PB - IEEE CY - Piscataway, NJ ER - TY - GEN A1 - Kahlert, Moritz A1 - Fei, Tai A1 - Tebruegge, Claas A1 - Gardill, Markus T1 - An Improved Stepped-Frequency PMCW Waveform for Automotive Radar Applications T2 - IEEE 15th German Microwave Conference (GeMiC), 11-13 March 2024, Duisburg, Germany N2 - 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. Y1 - 2024 U6 - https://doi.org/10.23919/GeMiC59120.2024.10485360 SN - 2167-8022 ER - TY - GEN A1 - Kahlert, Moritz A1 - Fei, Tai A1 - Wilden, Norwin A1 - Tebruegge, Claas A1 - Gardill, Markus T1 - MLS-based Transmitter Orthogonality Analysis in MIMO-PMCW Automotive Radar Systems T2 - IEEE 13rd Sensor Array and Multichannel Signal Processing Workshop (SAM), 08-11 July 2024, Corvallis, OR, USA N2 - 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. Y1 - 2024 U6 - https://doi.org/10.1109/SAM60225.2024.10636563 ER - TY - GEN A1 - Kahlert, Moritz A1 - Fei, Tai A1 - Tebruegge, Claas A1 - Gardill, Markus T1 - Range Migration Compensation for a PMCW Automotive Radar System T2 - 21st European Radar Conference (EuRAD), 04 November 2024, Paris, France N2 - 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. Y1 - 2024 U6 - https://doi.org/10.23919/EuRAD61604.2024.10734955 SP - 196 EP - 199 ER - TY - GEN A1 - Kahlert, Moritz A1 - Fei, Tai A1 - Tebruegge, Claas A1 - Gardill, Markus T1 - Stepped-frequency PMCW-radar modulation scheme for automotive applications T2 - IEEE Topical Conference on Wireless Sensors and Sensor Networks (WiSNet), 21-24 January 2024, San Antonio, TX, USA N2 - 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. Y1 - 2024 SN - 979-8-3503-2982-7 U6 - https://doi.org/10.1109/WiSNeT59910.2024.10438643 SN - 2473-4624 ER - TY - GEN A1 - Kahlert, Moritz A1 - Xu, Lifan A1 - Fei, Tai A1 - Gardill, Markus A1 - Sun, Shunqiao T1 - High-resolution DOA estimation using single-snapshot music for automotive radar with Mixed-ADC allocations T2 - IEEE 13rd Sensor Array and Multichannel Signal Processing Workshop (SAM), 08-11July 2024, Corvallis, OR, USA N2 - 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. Y1 - 2024 SN - 979-8-3503-4481-3 U6 - https://doi.org/10.1109/SAM60225.2024.10636418 SN - 2151-870X ER - TY - GEN A1 - Kahlert, Moritz A1 - Fei, Tai A1 - Tebruegge, Claas A1 - Gardill, Markus T1 - Doppler Ambiguity Resolution for a PMCW Automotive Radar System T2 - 20th European Radar Conference (EuRAD), 20-22 September 2023, Berlin (Germany) Y1 - 2023 SN - 978-2-87487-074-3 SN - 979-8-3503-2246-0 U6 - https://doi.org/10.23919/EuRAD58043.2023.10289445 SP - 73 EP - 76 PB - IEEE ER - TY - GEN A1 - Kahlert, Moritz A1 - Fei, Tai A1 - Hirner, Junus A1 - Tebruegge, Claas A1 - Gardill, Markus T1 - Multi-Target Doppler Ambiguity Identification for a PMCW Automotive Radar System T2 - 31st European Signal Processing Conference (EUSIPCO), 04-08 September 2023, Helsinki (Finland) Y1 - 2023 SN - 978-9-4645-9360-0 SN - 979-8-3503-2811-0 U6 - https://doi.org/10.23919/EUSIPCO58844.2023.10290009 SN - 2076-1465 SN - 2219-5491 SP - 795 EP - 799 PB - IEEE ER - TY - GEN A1 - Pearson, Dominik A1 - Scharnagl, Julian A1 - Schilling, Klaus A1 - Gardill, Markus T1 - Inter-Satellite Phase and Frequency Synchronization for Software-Defined CubeSat Radio Subsystems T2 - 2023 IEEE/MTT-S International Microwave Symposium : IMS : 11-16 June 2023, San Diego, California, USA Y1 - 2023 SN - 979-8-3503-4764-7 SN - 979-8-3503-4765-4 U6 - https://doi.org/10.1109/IMS37964.2023.10188146 SN - 2576-7216 SN - 0149-645X SP - 287 EP - 290 PB - IEEE CY - Piscataway, NJ ER - TY - GEN A1 - Schmidt, Marco A1 - Gardill, Markus A1 - Dietl, Guido T1 - Development of a new communication payload for the educational small satellite project UWE T2 - IAC 2023 congress proceedings, 74th International Astronautical Congress (IAC), October 2-6, 2023, Baku, Azerbaijan Y1 - 2023 UR - https://iafastro.directory/iac/paper/id/77343/summary/ ER - TY - GEN A1 - Kahlert, Moritz A1 - Pan, Jinwen A1 - Fei, Tai A1 - Tebruegge, Claas A1 - Gardill, Markus T1 - A Modular Ray Tracing-Based Framework for Automotive Radar Waveform Evaluation T2 - IEEE Topical Conference on Wireless Sensors and Sensor Networks (WiSNeT), 19-22 January 2025, San Juan, PR, USA N2 - Frequency-modulated continuous wave (FMCW) is the dominant waveform scheme in modern automotive radar systems used in advanced driver assistance systems (ADASs). Nevertheless, the digital modulation scheme phase-modulated continuous wave (PMCW) has recently attracted considerable interest due to advantages such as high maximum unambiguous velocities. However, there remains a need for more thorough performance assessments comparing these waveforms in dynamic automotive scenarios. This work presents a flexible framework comprising a ray-tracing simulator and radar models for efficient automotive scenario generation and radar simulation. Using this framework, the performance of FMCW and PMCW radar systems is assessed in a typical automotive scenario. The evaluation demonstrates that the PMCW radar system exhibits superior performance in terms of target detectability in the given scenario. Y1 - 2025 SN - 979-8-3315-0733-6 SN - 979-8-3315-0732-9 SN - 979-8-3315-0734-3 U6 - https://doi.org/10.1109/WiSNeT63956.2025.10905020 SN - 2473-4624 SN - 2330-7900 SP - 24 EP - 27 ER -