Non-Contact Human Motion Sensing Using Radar Techniques

Human motion analysis has recently gained a lot of interest in the research community due to its widespread applications. A full understanding of normal motion from human limb joint trajectory tracking could be essential to develop and establish a scientific basis for correcting any abnormalities. Technology to analyze human motion has significantly advanced in the last few years. However, there is a need to develop a non-invasive, cost effective gait analysis system that can be functional indoors or outdoors 24/7 without hindering the normal daily activities for the subjects being monitored or invading their privacy. Out of the various methods for human gait analysis, radar technique is a non-invasive method, and can be carried out remotely. For one subject monitoring, single tone radars can be utilized for motion capturing of a single target, while ultra-wideband radars can be used for multi-subject tracking. But there are still some challenges that need to be overcome for utilizing radars for motion analysis, such as sophisticated signal processing requirements, sensitivity to noise, and hardware imperfections. The goal of this research is to overcome these challenges and realize a non-contact gait analysis system capable of extracting different organ trajectories (like the torso, hands and legs) from a complex human motion such as walking. The implemented system can be hugely beneficial for applications such as treating patients with joint problems, athlete performance analysis, motion classification, and so on

FMCW-Radarsignalverarbeitung zur Entfernungsmessung mit hoher Genauigkeit

Entfernungsmessungen mit Genauigkeiten im Mikrometerbereich sind für die Regelung von industriellen Maschinen essentiell. In dieser Arbeit wird untersucht, welche Genauigkeiten mit FMCW‑Radaren, die eine zusätzliche Phasenauswertung einsetzen, erreicht werden können. In industriellen Anwendungen wird gezeigt, dass mit FMCW-Radaren Entfernungsmessungen in Bereichen ermöglicht werden, in denen es bisher nicht möglich war zu messen. Im Labor konnten Genauigkeiten < 1 μm nachgewiesen werden

Voltage controlled oscillator for mm-wave radio systems

Abstract. The advancement in silicon technology has accelerated the development of integrated millimeter-wave transceiver systems operating up to 100 GHz with sophisticated functionality at a reduced consumer cost. Due to the progress in the field of signal processing, frequency modulated continuous wave (FMCW) radar has become common in recent years. A high-performance local oscillator (LO) is required to generate reference signals utilized in these millimeter-wave radar transceivers. To accomplish this, novel design techniques in fundamental voltage controlled oscillators (VCO) are necessary to achieve low phase noise, wide frequency tuning range, and good power efficiency. Although integrated VCOs have been studied for decades, as we move higher in the radio frequency spectrum, there are new trade-offs in the performance parameters that require further characterization. The work described in this thesis aims to design a fully integrated fundamental VCO targeting to 150 GHz, i.e., D-Band. The purpose is to observe and analyze the design limitations at these high frequencies and their corresponding trade-offs during the design procedure. The topology selected for this study is the cross-coupled LC tank VCO. For the study, two design topologies were considered: a conventional cross-coupled LC tank VCO and an inductive divider cross-coupled LC tank VCO. The conventional LC tank VCO yields better performance in terms of phase noise and tuning range. It is observed that the VCO is highly sensitive to parasitic contributions by the transistors, and the layout interconnects, thus limiting the targeted frequency range. The dimensions of the LC tank and the transistors are selected carefully. Moreover, the VCO performance is limited by the low Q factor of the LC tank governed by the varactor that is degrading the phase noise performance and the tuning range, respectively. The output buffer loaded capacitance and the core power consumption of the VCO are optimized. The layout is drawn carefully with strategies to minimize the parasitic effects. Considering all the design challenges, a 126 GHz VCO with a tuning range of 3.9% is designed. It achieves FOMT (Figure-of-merit) of -172 dBc/Hz, and phase noise of -99.14 dBc/Hz at 10 MHz offset, Core power consumption is 8.9 mW from a 1.2 V supply. Just falling short of the targeted frequency, the design is suitable for FMCW radar applications for future technologies. The design was done using Silicon-on-Insulator (SOI) CMOS technology

LASER Tech Briefs, Spring 1994

Topics in this Laser Tech Brief include: Electronic Components and Circuits. Electronic Systems, Physical Sciences, Materials, Mechanics, Fabrication Technology, and books and reports

Absolute distance (thickness) metrology using wavelength scanning interferometry

Wavelength scanning interferometry offers a new dimension in precision metrology by measuring the cavity length (thickness), the cavity length variation over the cavity area (flatness), and the optical homogeneity within a transparent cavity; without any mechanical movement by implementing a tunable laser. This property is useful when the physical movement of an optic is not feasible using traditional phase shifting methods employing piezoelectric transducers and for characterizing solid optical cavities which require movement of one surface relative to the other. The cavity length that can be measured is limited by the wavelength scanning range - a smaller cavity requires a larger tuning range. Tunable lasers are now available with very large tuning ranges in the near infrared, potentially extending the measurement range significantly. The use of Fourier analysis on the intensity (interference) time history as a post processing step enables the measurement of cavity lengths without any 2p phase ambiguity. This study demonstrates absolute length (thickness) measurements of various artifacts such as the thickness of a transparent window, gauge blocks, and the diameter of transparent spherical cavities such as a ball lens on a commercial wavelength scanning Fizeau interferometer. A mathematical model of the measurement process is demonstrated along with a software simulation model to understand the impact of dynamic parameters such as tuning rate on the thickness. Finally, a custom built wavelength scanning interferometer is designed from an existing wideband tunable laser in-house to demonstrate the thickness of sub-mm windows

Millimeterwellen On-Chip Antennensysteme für die Integration in SoC Applikationen

In dieser Arbeit werden Antennensysteme für Radar- und Kommunikationssysteme präsentiert. Zusätzlich wird ein QFN Gehäusekonzept erarbeitet. Bei den Antennensystemen für Kommunikationsanwendungen liegt der Fokus auf der Maximierung der abgestrahlten Leistung, um die Reichweite zu erhöhen. Es wird ein neuartiges Konzept zur Leistungskombination von parallelisierten Verstärkern aufgezeigt, bei dem die Signale der einzelnen Verstärker im Antennenelement kombiniert werden