Automotive Frequency Modulated Continuous Wave Radar Interference Reduction Using Per-Vehicle Chirp Sequences

Recently, many automobiles adopt radar sensors to support advanced driver assistance system (ADAS) functions. As the number of vehicles with radar systems increases the probability of radar signal interference and the accompanying ghost target problems become serious. In this paper, we propose a novel algorithm where we deploy per-vehicle chirp sequence in a frequency modulated continuous wave (FMCW) radar to mitigate the vehicle-to-vehicle radar interference. We devise a chirp sequence set so that the slope of each vehicle’s chirp sequence does not overlap within the set. By assigning one of the chirp sequences to each vehicle, we mitigate the interference from the radar signals transmitted by the neighboring vehicles. We confirm the performance of the proposed method stochastically by computer simulation. The simulation results show that the detection and false alarm performance is improved significantly by the proposed method.

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Gas Flow Monitoring in High and Low Reynolds Regimes Based on Compensated FMCW-Radar Phase Measurements

Frequenz ◽

10.1515/freq-2016-0216 ◽

2017 ◽

Vol 71 (3-4) ◽

Cited By ~ 3

Author(s):

Birk Hattenhorst ◽

Christoph Baer ◽

Thomas Musch ◽

Timo Jaeschke ◽

Nils Pohl

Keyword(s):

Gas Flow ◽

Continuous Wave ◽

Phase Measurements ◽

Fmcw Radar ◽

Flow Monitoring ◽

Radar Systems ◽

Wave Radar ◽

Measurement Signal ◽

Gaseous Media ◽

Low Jitter

AbstractIn this contribution, a composite measurement concept for the gas flow determination in diverse stream scenarios is presented. The approach utilizes the pressure- and mixing-dependent relative permittivity of gaseous media, which, in case of a vortex or a marker gas, creates a detectable variation in the measuring beam of the radar. Since the measurement effect is very small, phase measurements based on highly precise and low jitter frequency-modulated continuous-wave radar systems in different frequency bands are applied. Moreover, disturbances caused by vibrations of the measurement setup are compensated out of the measurement signal.

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Evaluation of a robust correlation-based true-speed-over-ground measurement system employing a FMCW radar

International Journal of Microwave and Wireless Technologies ◽

10.1017/s1759078719000928 ◽

2019 ◽

Vol 11 (7) ◽

pp. 686-693 ◽

Cited By ~ 1

Author(s):

Torsten Reissland ◽

Bjoern Lenhart ◽

Johann Lichtblau ◽

Michael Sporer ◽

Robert Weigel ◽

...

Keyword(s):

Continuous Wave ◽

Field Measurements ◽

Proof Of Concept ◽

Fmcw Radar ◽

Radar Sensors ◽

Novel Approach ◽

Ground Measurement ◽

Wave Radar ◽

24 Ghz

AbstractThis paper presents a novel approach for the determination of True-Speed-Over-Ground for trains. Speed determination is accomplished by correlating the received signals of two side-looking radar sensors. The theoretically achievable precision is derived. Test measurements are done in two different scenarios to give a proof of concept. Thereafter a series of field measurements is performed to rate the practical suitability of the approach. The results of the measurements are thoroughly evaluated. The test and field measurements are carried out using a 24 GHz frequency modulated continuous wave radar.

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Low-Complexity 2D-MUSIC for Joint Range and Angle Estimation of Frequency Modulated Continuous-Wave Radar

Journal of Electromagnetic Engineering and Science ◽

10.26866/jees.2021.5.r.48 ◽

2021 ◽

Vol 21 (5) ◽

pp. 399-405

Author(s):

Yongchul Jung ◽

Seunghyeok Lee ◽

Seongjoo Lee ◽

Yunho Jung

Keyword(s):

Continuous Wave ◽

Low Complexity ◽

Processing Technique ◽

Angle Estimation ◽

Multiple Signal Classification ◽

Fmcw Radar ◽

Radar Systems ◽

Wave Radar ◽

Preprocessing Technique ◽

Joint Range

A pre-processing technique is proposed to reduce the complexity of two-dimensional multiple signal classification (2D-MUSIC) for the joint range and angle estimation of frequency-modulated continuous-wave (FMCW) radar systems. By using the central symmetry of the angle steering vector from a uniform linear array (ULA) antenna and the linearity of the beat signal in the FMCW radar, this preprocessing technique transforms 2D-MUSIC from complex values into real values. To compare the computational complexity of the proposed algorithm with the conventional 2D-MUSIC, we measured the CPU processing time for various numbers of snapshots, and the evaluation results indicated that the 2D-MUSIC with the proposed pre-processing technique is approximately three times faster than the conventional 2D-MUSIC.

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Single-Channel FMCW-Radar-Based Multi-Passenger Occupancy Detection Inside Vehicle

Entropy ◽

10.3390/e23111472 ◽

2021 ◽

Vol 23 (11) ◽

pp. 1472

Author(s):

Heemang Song ◽

Hyun-Chool Shin

Keyword(s):

Continuous Wave ◽

Single Channel ◽

Spectral Power ◽

Likelihood Estimation ◽

Radar Signal ◽

Linear Discriminant ◽

Fmcw Radar ◽

Time Frequency ◽

Occupancy Detection ◽

Wave Radar

In this paper, we provide the results of multi-passenger occupancy detection inside a vehicle obtained using a single-channel frequency-modulated continuous-wave radar. The physiological characteristics of the radar signal are analyzed in a time-frequency spectrum, and features are proposed based on these characteristics for multi-passenger occupancy detection. After clutter removal is applied, the spectral power and Wiener entropy are proposed as features to quantify physiological movements arising from breathing and heartbeat. Using the average means of both the power and Wiener entropy at seats 1 and 2, the feature distributions are expressed, and classification is performed. The multi-passenger occupancy detection performance is evaluated using linear discriminant analysis and maximum likelihood estimation. The results indicate that the proposed power and Wiener entropy are effective features for multi-passenger occupancy detection.

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Applications of radar measurement technology using 24 GHz, 61 GHz, 80 GHz and 122 GHz FMCW radar sensors

tm - Technisches Messen ◽

10.1515/teme-2021-0034 ◽

2021 ◽

Vol 0 (0) ◽

Author(s):

Akanksha Bhutani ◽

Sören Marahrens ◽

Marius Kretschmann ◽

Serdal Ayhan ◽

Steffen Scherr ◽

...

Keyword(s):

Measurement Accuracy ◽

Continuous Wave ◽

Estimation Method ◽

Signal Propagation ◽

Distance Measurement ◽

Radar Signal ◽

Measurement Technology ◽

Fmcw Radar ◽

Radar Sensors ◽

24 Ghz

Abstract This paper presents a review of radar applications in high-accuracy distance measurement of a target. The radars included in this review are frequency modulated continuous wave (FMCW) radar sensors operating in four different millimeter-wave frequency bands, namely 24 GHz, 61 GHz, 80 GHz and 122 GHz. The radar sensors are used to measure the distance of standard and complex targets in a short range of a few meters, thus indicating that the choice of target and the medium used for radar signal propagation also play a key role in determining the distance measurement accuracy of an FMCW radar. The standard target is a trihedral corner reflector in a laboratory-based free space measurement setup and the complex targets include a piston in an oil-filled hydraulic cylinder and a planar positioning stage used in micromachining. In each of these measurement scenarios, a distance measurement accuracy in micrometer range is achieved due to the use of a sophisticated signal processing algorithm that is based on a combined frequency and phase estimation method. The paper is concluded with a technical comparison of the accuracy achieved by the FMCW radars reviewed in this article with other related works.

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Concept and realization of a low-cost multi-target simulator for CW and FMCW radar system calibration and testing

International Journal of Microwave and Wireless Technologies ◽

10.1017/s1759078718000028 ◽

2018 ◽

Vol 10 (2) ◽

pp. 207-215 ◽

Cited By ~ 2

Author(s):

Werner Scheiblhofer ◽

Reinhard Feger ◽

Andreas Haderer ◽

Andreas Stelzer

Keyword(s):

Continuous Wave ◽

Doppler Radar ◽

Dynamic Range ◽

Low Cost ◽

Intermediate Frequency ◽

Radar System ◽

Fmcw Radar ◽

Radar Systems ◽

Single Target ◽

Wave Radar

AbstractWe present the realization of an frequency-modulated continuous-wave radar target simulator, based on a modulated-reflector radar system. The simulator, designed for the 24 GHz frequency band, uses low-cost modulated-reflector nodes and is capable to simultaneously generate multiple targets in a real-time environment. The realization is based on a modular approach and thus provides a high scalability of the whole system. It is demonstrated that the concept is able to simulate multiple artificial targets, located at user-selectable ranges and even velocities, utilized within a completely static setup. The characterization of the developed hardware shows that the proposed concept allows to dynamically and precisely adjust the radar cross-section of each single target within a dynamic range of 50 dB. Additionally, the provided range-proportional target frequency bandwidth makes the system perfectly suitable for fast and reliable intermediate frequency-chain calibration of multi-channel radar systems. Within this paper we demonstrate the application of the concept for a linear sweeped frequency-modulated continuous-wave radar. The presented approach is applicable to any microwave-based measurement system using frequency differences between transmit- and receive signals for range- and velocity evaluation, such as (non-)linear sweeped as well as pure Doppler radar systems.

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Computer Tool for Simulating Frequency Modulated -Continuous Wave Radar Systems in Urban Traffic Scenes

12th European Conference on Antennas and Propagation (EuCAP 2018) ◽

10.1049/cp.2018.0544 ◽

2018 ◽

Author(s):

A. Somolinos ◽

J.-L. García ◽

L. Lozano ◽

I. González ◽

F. Cátedra

Keyword(s):

Continuous Wave ◽

Urban Traffic ◽

Computer Tool ◽

Radar Systems ◽

Wave Radar

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FPGA Implementation of an Efficient FFT Processor for FMCW Radar Signal Processing

Sensors ◽

10.3390/s21196443 ◽

2021 ◽

Vol 21 (19) ◽

pp. 6443

Author(s):

Jinmoo Heo ◽

Yongchul Jung ◽

Seongjoo Lee ◽

Yunho Jung

Keyword(s):

Signal Processing ◽

Detection Rate ◽

Continuous Wave ◽

Vital Signs ◽

Radar Signal ◽

Radar Signal Processing ◽

Fmcw Radar ◽

Design And Implementation ◽

Fft Processor ◽

Point Operator

This paper presents the design and implementation results of an efficient fast Fourier transform (FFT) processor for frequency-modulated continuous wave (FMCW) radar signal processing. The proposed FFT processor is designed with a memory-based FFT architecture and supports variable lengths from 64 to 4096. Moreover, it is designed with a floating-point operator to prevent the performance degradation of fixed-point operators. FMCW radar signal processing requires windowing operations to increase the target detection rate by reducing clutter side lobes, magnitude calculation operations based on the FFT results to detect the target, and accumulation operations to improve the detection performance of the target. In addition, in some applications such as the measurement of vital signs, the phase of the FFT result has to be calculated. In general, only the FFT is implemented in the hardware, and the other FMCW radar signal processing is performed in the software. The proposed FFT processor implements not only the FFT, but also windowing, accumulation, and magnitude/phase calculations in the hardware. Therefore, compared with a processor implementing only the FFT, the proposed FFT processor uses 1.69 times the hardware resources but achieves an execution time 7.32 times shorter.

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