The Experts below are selected from a list of 20640 Experts worldwide ranked by ideXlab platform
Juha Kostamovaara - One of the best experts on this subject based on the ideXlab platform.
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a wide dynamic range cmos laser radar receiver with a time domain walk error compensation scheme
IEEE Transactions on Circuits and Systems I-regular Papers, 2017Co-Authors: Sami Kurtti, Jan Nissinen, Juha KostamovaaraAbstract:This integrated receiver channel designed for a Pulsed time-of-flight (TOF) laser rangefinder consists of a fully differential transimpedance amplifier channel and a timing discriminator. The amplitude-dependent timing walk error is compensated by measuring the width and rise time of the Received Pulse echo and using this information for calibration. The measured bandwidth, transimpedance and minimum detectable signal (SNR ~10) of the receiver channel are 230 MHz, $100~\text {k}\Omega $ and ${\sim } 1~\mu \text {A}$ respectively. The single-shot precision of the receiver is ~3 cm at an SNR of 13 and the measurement accuracy is ±4 mm with compensation within a dynamic range of ~1:100 000. The receiver circuit was realized in a $0.35~\mu \text {m}$ CMOS process and has a power consumption of 150 mW. The functionality of the receiver channel was verified over a temperature range of -20 °C to +50 °C.
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An Integrated Laser Radar Receiver Channel Utilizing a Time-Domain Walk Error Compensation Scheme
IEEE Transactions on Instrumentation and Measurement, 2011Co-Authors: Sami Kurtti, Juha KostamovaaraAbstract:An integrated receiver channel for a Pulsed time-of-flight (TOF) laser rangefinder has been designed and fabricated in a 0.35-μm SiGe BiCMOS process. The receiver channel generates a timing mark for the TDC by means of a leading-edge timing discriminator that detects the crossover of the Received Pulse with respect to a set reference level. The walk error generated by the amplitude variation is compensated in the time domain on the basis of the measured dependence of the walk on the length of the Received Pulse. The measurement accuracy is ±15 ps with compensation within a dynamic range of 1:100000, and the single-shot precision and power consumption are 120 ps for a minimum detectable signal of ~1 μA and 115 mW, respectively.
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effect of photonic shot noise on optimum leading edge detection level of laser Pulses
Proceedings of SPIE the International Society for Optical Engineering, 2008Co-Authors: Lauri Hallman, Juha KostamovaaraAbstract:In time-of-flight laser distance measurement a nanosecond-class laser Pulse is reflected off a target, and the distance to the target is calculated from the flight time of the Pulse. The distance measurement precision is directly proportional to the jitter of the Pulse (i.e. the uncertainty of the arrival time of the Pulse due to noise). In this work, the effect of signal quantum shot noise on the jitter of detected laser Pulses was researched. It was discovered that signal quantum shot noise drives the optimal detection level of the Pulse lower because shot noise increases along with Received Pulse power. The effect is more significant with an AP-diode receiver than with a PIN diode receiver due to the avalanche multiplication of shot noise in an AP-diode. This jitter phenomenon was modeled in Matlab, and the result was verified by measurements.
Sami Kurtti - One of the best experts on this subject based on the ideXlab platform.
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a wide dynamic range cmos laser radar receiver with a time domain walk error compensation scheme
IEEE Transactions on Circuits and Systems I-regular Papers, 2017Co-Authors: Sami Kurtti, Jan Nissinen, Juha KostamovaaraAbstract:This integrated receiver channel designed for a Pulsed time-of-flight (TOF) laser rangefinder consists of a fully differential transimpedance amplifier channel and a timing discriminator. The amplitude-dependent timing walk error is compensated by measuring the width and rise time of the Received Pulse echo and using this information for calibration. The measured bandwidth, transimpedance and minimum detectable signal (SNR ~10) of the receiver channel are 230 MHz, $100~\text {k}\Omega $ and ${\sim } 1~\mu \text {A}$ respectively. The single-shot precision of the receiver is ~3 cm at an SNR of 13 and the measurement accuracy is ±4 mm with compensation within a dynamic range of ~1:100 000. The receiver circuit was realized in a $0.35~\mu \text {m}$ CMOS process and has a power consumption of 150 mW. The functionality of the receiver channel was verified over a temperature range of -20 °C to +50 °C.
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An Integrated Laser Radar Receiver Channel Utilizing a Time-Domain Walk Error Compensation Scheme
IEEE Transactions on Instrumentation and Measurement, 2011Co-Authors: Sami Kurtti, Juha KostamovaaraAbstract:An integrated receiver channel for a Pulsed time-of-flight (TOF) laser rangefinder has been designed and fabricated in a 0.35-μm SiGe BiCMOS process. The receiver channel generates a timing mark for the TDC by means of a leading-edge timing discriminator that detects the crossover of the Received Pulse with respect to a set reference level. The walk error generated by the amplitude variation is compensated in the time domain on the basis of the measured dependence of the walk on the length of the Received Pulse. The measurement accuracy is ±15 ps with compensation within a dynamic range of 1:100000, and the single-shot precision and power consumption are 120 ps for a minimum detectable signal of ~1 μA and 115 mW, respectively.
Jaafar M H Elmirghani - One of the best experts on this subject based on the ideXlab platform.
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optimization of a triangular pfdr antenna in a fully diffuse ow system influenced by background noise and multipath propagation
IEEE Transactions on Communications, 2003Co-Authors: A G Alghamdi, Jaafar M H ElmirghaniAbstract:Optical wireless (OW) systems are generally impaired by multipath propagation and directional interference in the form of background noise. We present original results for a fully diffuse OW system that employs a novel triangular pyramidal fly-eye diversity receiver (PFDR). The Received Pulse shapes are evaluated at various locations on the communication floor and the background noise collected on the three faces of the pyramid is determined. It is demonstrated that, through optimization of the PFDR field-of-view, the directional background interference can be reduced and that the Received Pulse shape can be improved. The computed error probability shows a marked improvement when our optimized PFDR antenna is used instead of the conventional photodetector used in traditional diffuse optical wireless systems.
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slot synchronization in optical fiber ppm systems with gaussian type Received Pulse shapes
Microwave and Optical Technology Letters, 1993Co-Authors: R A Cryan, Jaafar M H Elmirghani, F M ClaytonAbstract:The problem of determining the precise slot boundaries is an essential one in optical-fiber Pulse position modulation (PPM) systems due to the temporal nature of the format. Here we present an original spectral characterization of the PPM process and establish the requirements to realize a discrete spectral slot rate component. In particular we show that this component is independent of the modulation index and data probability distribution. The dependence of the component on Pulse shapes is investigated and examined for the important class of dispersed Gaussian-type Pulse shapes normally associated with optical-fiber transmission. Original practical results, measured on a 128-slot PPM system, are presented and shown to be in agreement with the theoretical predictions to within 1 dB. © 1993 John Wiley & Sons, Inc.
Ghavami M - One of the best experts on this subject based on the ideXlab platform.
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Signature Inspired Home Environments Monitoring System using IRUWB Technology
'MDPI AG', 2019Co-Authors: Dudley S, Rana S., Dey M, Ghavami MAbstract:Home monitoring and remote care systems aim to ultimately provide independent living care scenarios through non-intrusive, privacy-protecting means. Their main aim is to provide care through appreciating normal habits, remotely recognizing changes and acting upon those changes either through informing the person themselves, care providers, family members, medical practitioners or emergency services depending on need. Care giving can be required at any age, encompassing young to the globally growing aging population. A non-wearable and unobtrusive architecture have been developed and tested here to provide a fruitful health and wellbeing-monitoring framework without interfering in a user’s regular daily habits and maintaining privacy. This work focuses on tracking locations in an unobtrusive way, recognizing daily activities, 1which are part of maintaining a healthy/regular lifestyle. This study shows an intelligent and locally based edge care system (ECS) solution to identify the location of an occupant’s movement from daily activities using imPulse radio-ultra wide band (IR-UWB) radar. A new method is proposed calculating the azimuth angle of a movement from the Received Pulse and employing radar principles to determine the range of that movement. Moreover, short-term fourier transform (STFT) has been performed to determine the frequency distribution of the occupant’s action. Therefore, STFT, azimuth angle, and range calculation together provide the information to understand how occupants engage with their environment. An experiment has been carried out for an occupant at different times of a day during daily household activities and recorded with time and room position. Subsequently, these time-frequency outcomes, along with the range and azimuth information have been employed to train a support vector machine (SVM) learning algorithm for recognizing indoor locations when the person is moving around the house where little or no movement indicates the occurrence of abnormalities. The implemented framework is connected with a cloud server architecture, which enables to act against any abnormality remotely. The proposed methodology shows very promising results through statistical validation and achieved over 90% testing accuracy in a real-time scenario
Jan Nissinen - One of the best experts on this subject based on the ideXlab platform.
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a wide dynamic range cmos laser radar receiver with a time domain walk error compensation scheme
IEEE Transactions on Circuits and Systems I-regular Papers, 2017Co-Authors: Sami Kurtti, Jan Nissinen, Juha KostamovaaraAbstract:This integrated receiver channel designed for a Pulsed time-of-flight (TOF) laser rangefinder consists of a fully differential transimpedance amplifier channel and a timing discriminator. The amplitude-dependent timing walk error is compensated by measuring the width and rise time of the Received Pulse echo and using this information for calibration. The measured bandwidth, transimpedance and minimum detectable signal (SNR ~10) of the receiver channel are 230 MHz, $100~\text {k}\Omega $ and ${\sim } 1~\mu \text {A}$ respectively. The single-shot precision of the receiver is ~3 cm at an SNR of 13 and the measurement accuracy is ±4 mm with compensation within a dynamic range of ~1:100 000. The receiver circuit was realized in a $0.35~\mu \text {m}$ CMOS process and has a power consumption of 150 mW. The functionality of the receiver channel was verified over a temperature range of -20 °C to +50 °C.
