Radar-Based Structural Health Monitoring | #StructuralHealthMonitoring #mmWaveRadar #MIMORadar #FMCWRadar #DisplacementMeasurement

Robust Displacement Estimation in Fast-Moving Structures Using Doppler-Aware mmWave Radar Processing

Radars offer high resolution but face challenges such as phase wrapping when tracking fast-moving targets. To address this, the authors propose an iterative phase unwrapping technique that leverages Doppler information to recover accurate displacement data. Experimental results demonstrate the effectiveness of the approach in capturing fine-scale movements even under conditions where traditional radar methods fail. The method is particularly useful for non-contact structural health monitoring, offering low complexity and high precision.


Background and Motivation

The increasing demand for robust, precise, and non-invasive monitoring tools in structural health monitoring (SHM) has driven the exploration of advanced radar technologies. Among these, millimeter-wave (mmWave) MIMO FMCW radar systems have gained substantial attention due to their ability to provide high-resolution measurements, wide field of view, and the capability to monitor multiple points simultaneously.

Traditional displacement sensors like LVDTs, LDVs, and vision-based systems are often hindered by environmental sensitivity, installation constraints, or lack of portability. In contrast, ground-based mmWave radar offers a powerful alternative. By transmitting continuous waveforms with frequency modulation, these radars can track micro-movements by analyzing phase changes in the received signal. However, one of the major obstacles in achieving high-fidelity displacement data is the phase wrapping problem, which occurs when displacement between samples exceeds a quarter of the radar wavelength.

Phase Wrapping Challenge

The phase wrapping issue is rooted in the nature of wave-based displacement measurement. Since the radar measures only the phase shift of the reflected wave, it cannot distinguish between phase shifts that differ by multiples of 2π. When a structure moves too fast between radar snapshots—specifically, more than a quarter of the radar’s wavelength—this causes ambiguity in displacement calculation. Without correction, this results in inaccurate or even misleading displacement estimates.

For mmWave radars operating at 60–77 GHz, the wavelength is just a few millimeters. Thus, even small but rapid movements can induce significant phase wrapping, especially in scenarios involving high-frequency vibrations or sudden structural responses (e.g., due to wind or traffic loads).

Proposed Solution: Doppler-Based Iterative Phase Unwrapping

To overcome the phase ambiguity, this research proposes a Doppler-aided phase unwrapping algorithm. The Doppler shift, which provides an estimate of the target's velocity, can be used to predict the expected phase change over time. By integrating Doppler information with the phase data, the algorithm iteratively unwraps the phase trajectory, reconstructing the true displacement profile.

This method is particularly effective because:

  • It does not require additional sensors.

  • It operates in real-time with low computational complexity.

  • It enhances displacement accuracy even in high-speed or high-frequency dynamic environments.

Applications and Future Directions

The proposed method enables precise, contactless monitoring of fast-moving structures, which is critical in various SHM scenarios:

  • Monitoring of bridges under dynamic loading (e.g., from vehicles or earthquakes).

  • Assessment of high-rise buildings during wind-induced oscillations.

  • Detection of early signs of mechanical fatigue or failure in industrial structures.

Future research may focus on:

  • Extending the algorithm for 3D displacement tracking.

  • Integrating radar data with AI/ML models for anomaly detection.

  • Miniaturizing radar units for deployment on drones or autonomous vehicles for remote inspection.

#sciencefather #phenimenalogical #researchawards #StructuralHealthMonitoring #mmWaveRadar  #MIMORadar #FMCWRadar #DisplacementMeasurement

International Phenomenological Research Awards
Contact Us For Enquiry: contact@phenomenologicalresearch.com

#phenomenology #researchawards #internationalawards #academicrecognition #qualitativeresearch #phenomenologicalstudies #scholarlyachievement #researchexcellence #humanscienceresearch #professor #academic #sciencefather #voicetherapy #mentaleffort #patientperception #vocalrehabilitation #speechtherapy #cognitiveload #patientexperience #therapeuticoutcomes #voicehealth #healthcarepsychology

Comments

Post a Comment

Popular posts from this blog

Climate change

Image
  Climate change presents a fundamental threat to human health. It affects the physical environment as well as all aspects of both natural and human systems – including social and economic conditions and the functioning of health systems. It is therefore a threat multiplier, undermining and potentially reversing decades of health progress. As climatic conditions change, more frequent and intensifying weather and climate events are observed, including storms, extreme heat, floods, droughts and wildfires. These weather and climate hazards affect health both directly and indirectly, increasing the risk of deaths, noncommunicable diseases, the emergence and spread of infectious diseases, and health emergencies. Climate change impacts on health Climate change is impacting health in a myriad of ways, including by leading to death and illness from increasingly frequent extreme weather events, such as heatwaves, storms and floods, the disruption of food systems, increases in zoonoses an...
Read more
Image
  What is Ontology ? Ontology is a branch of philosophy that explores the nature of being, existence, and reality. It seeks to answer fundamental questions like: What exists? What are the essential categories of existence? How do these entities relate to each other? In essence, ontology serves as the foundation for understanding the structure of reality, both tangible and abstract. Ontology in Philosophy Philosophical ontology delves into the fundamental components of existence. It classifies entities into categories, such as: Material Objects: Physical entities like rocks, trees, and stars. Abstract Concepts: Ideas, numbers, and relationships. Processes: Actions or events like running or melting. Ontology also intersects with metaphysics, exploring the nature of time, space, causality, and identity. Ontology in Technology In the digital realm, ontology takes a different but equally significant role. It is used in: Artificial Intelligence (AI): Building knowledge graphs and u...
Read more
Image
  Reflexivity is a term often discussed in the context of research, particularly qualitative studies. But what does it truly mean, and why is it so important? Reflexivity is the process of reflecting on and critically examining the role that a researcher’s background, experiences, and perspectives play in shaping the research process and outcomes. It's about acknowledging the subjectivity of knowledge creation and recognizing how our personal biases, assumptions, and values influence the way we interpret data, interact with participants, and present our findings. Why is Reflexivity Important? In any research study, especially those in social sciences or humanities, researchers bring their own worldview, assumptions, and biases to the table. These factors can subtly, or overtly, influence how data is gathered, analyzed, and interpreted. Reflexivity encourages researchers to step back and reflect on these influences, ensuring a more transparent, ethical, and self-aware approach to ...
Read more