Passive IR Sensors Research Articles

Modeling the Performance of Mosaic Uncooled Passive IR Sensors in CMOS–SOI Technology

This paper analyzes the performance of mosaic nonimaging passive infrared (PIR) sensors fabricated by the CMOS–SOI–MEMS technology. The elementary sensor, forming a subpixel, is a thermally isolated nanomachined CMOS transistor, dubbed TMOS, operating at subthreshold. The mosaic uncooled PIR sensors are composed of several TMOS subpixels, which are electrically connected, either in parallel or in series as well as a combination of both options. These mosaic sensors, which are manufactured by nanofabrication methods, exhibit enhanced performance and robust manufacturing on wafer level. The overall figures of merit of these sensors, which are modeled in this paper, indicate why they are most suitable for consumer electronics, including smart homes, wearables, Internet of Things as well as mobile applications.

Animal Classification System Based on Image Processing & Support Vector Machine

This project is mainly focused to develop system for animal researchers & wild life photographers to overcome so many challenges in their day life today. When they engage in such situation, they need to be patiently waiting for long hours, maybe several days in whatever location and under severe weather conditions until capturing what they are interested in. Also there is a big demand for rare wild life photo graphs. The proposed method makes the task automatically use microcontroller controlled camera, image processing and machine learning techniques. First with the aid of microcontroller and four passive IR sensors system will automatically detect the presence of animal and rotate the camera toward that direction. Then the motion detection algorithm will get the animal into middle of the frame and capture by high end auto focus web cam. Then the captured images send to the PC and are compared with photograph database to check whether the animal is exactly the same as the photographer choice. If that captured animal is the exactly one who need to capture then it will automatically capture more. Though there are several technologies available none of these are capable of recognizing what it captures. There is no detection of animal presence in different angles. Most of available equipment uses a set of PIR sensors and whatever it disturbs the IR field will automatically be captured and stored. Night time images are black and white and have less details and clarity due to infrared flash quality. If the infrared flash is designed for best image quality, range will be sacrificed. The photographer might be interested in a specific animal but there is no facility to recognize automatically whether captured animal is the photographer’s choice or not.

Tracking Motion Direction and Distance With Pyroelectric IR Sensors

Passive IR (PIR) sensors are excellent devices for wireless sensor networks (WSN), being low-cost, low-power, and presenting a small form factor. PIR sensors are widely used as a simple, but reliable, presence trigger for alarms, and automatic lighting systems. However, the output of a PIR sensor depends on several aspects beyond simple people presence, as, e.g., distance of the body from the sensor, direction of movement, and presence of multiple people. In this paper, we present a feature extraction and sensor fusion technique that exploits a set of wireless nodes equipped with PIR sensors to track people moving in a hallway. Our approach has reduced computational and memory requirements, thus it is well suited for digital systems with limited resources, such as those available in sensor nodes. Using the proposed techniques, we were able to achieve 100% correct detection of direction of movement and 83.49%-95.35% correct detection of distance intervals.

Correlation spectroscopy with diffractive grating synthetic spectra and orthogonal subspace projection filters

We evaluate the feasibility of implementing correlation spec- troscopy for remote sensing with a passive IR sensor that incorporates a diffractive grating on which a synthetic spectrum is imbedded. The spec- tral diffraction reflectances of diffractive gratings are measured and com- pared to the theoretical design spectra and to the library absorbance spectra. Five gratings are evaluated: sulfur hexafluoride (SF6), ((dimethoxyphosphinothioyl)thio)butanedioic acid, diethyl ester (malathion), diisopropyl-methylphosphonate (DIMP), methylphosphono- fluoridic acid,(1-methylethyl) ester (Sarin or GB), and O-ethyl-S-(2- diisopropylamino)ethyl methylphosphonothioate (VX). While the gratings were designed from liquid phase infrared spectra, the measurements and models provide a satisfactory proof of principle for the exploitation of synthetic spectra in correlation spectroscopy. The predicted noise equivalent concentration pathlength (NECL) for detecting GB and VX in a desert environment is computed for distances up to 5 km. The device was found to have high sensitivity in terms of NECL. The selectivity of the grating is found to be poor, but can be improved dramatically with the use of orthogonal subspace projection (OSP) filters that reduce the false alarm (improve selectivity) from misidentifying a GB as VX (and vice versa) at the ''cost'' of a slight increase of the NECL (reduce sensitivity). © 2003 Society of Photo-Optical Instrumentation Engineers. (DOI: 10.1117/1.1531638) Subject terms: correlation spectroscopy; infrared spectroscopy; orthogonal sub- space projection (OSP); vapor detection; false alarm; diffractive optics; synthetic spectra.

Passive polarimetric IR target classification

Automatic detection and recognition of targets by means of passive IR sensors suffer from limitations due to lack of sufficient contrast between the targets and, their backgrounds and among the facets of a target. A set of novel algorithms is designed and tested that uses the target and background Stokes parameters for detection, segmentation, and classification of targets, In these algorithms, it is assumed that for each pixel in the image data three of the four Stokes parameters are provided. This assumption is justified because we have developed a custom designed Polarimetric IR (PIR) imaging sensor that generates three of the Stokes parameters at each pixel location, in real-time. The empirical performance of the above algorithms, in terms of the probabilities of detection, false alarm rate, segmentation accuracy, and recognition probabilities are computed. The comparison of these results with the results associated with intensity-only imaging sensor (nonpolarimetric IR sensory data) shows that use of polarimetric information can noticeably improve the performance.

Application of a passive polarimetric infrared sensor in improved detection and classification of targets

Automatic detection and recognition of targets by means of passive IR sensors suffer from limitations due to lack of sufficient contrast between the targets and their background, and among the facets of a target. In this paper the results of a suite of polarization-sensitive automatic target detection and recognition algorithms on sets of simulated and real polarimetric IR imagery are presented. A custom designed Polarimetric IR (PIR) imaging sensor is used for collecting real polarimetric target data-three of the four Stokes parameters under a variety of conditions. Then a set of novel algorithms are designed and tested that uses the target and background Stokes parameters for detection, segmentation and classification of targets. The empirical performance results are obtained in terms of the probabilities of detection, false alarm rate, segmentation accuracy, and recognition probabilities as functions of number of pixels on target, aspect and depression angles and under several background conditions (clutter densities) on the polarimetric and non-polarimetrirc data. These results show that a noticeable improvement over the non-polarimetric ATR can be achieved.

A space station-based orbital debris tracking system

Orbital debris with dimensions between 1 and 10 cm is an increasing threat to the Space Station Freedom. A possible solution is to track the debris with a station-based radar and passive IR sensors. Studies at JSC have shown that the approach window of the debris is relatively narrow, ± 10° in elevation and ± (30° to 90°) in azimuth. Preliminary JSC studies suggest that angle and range accuracies of 10 −4 radians and 6 m are required for trajectory determination. Design considerations for minimizing the costs of a microwave array antenna are discussed. A proposed ground-based radar/antenna experiment for tracking small particles with high angular rates is described.

Radiometric analysis of infrared sensor performance

The performance of IR sensors for target detection is analyzed with model SENSAT. The model calculates the radiometric relations for passive IR sensors with up to three homogeneous objects in the instantaneous field of view. For the atmospheric part, the computer code LOwTRAN-6 is used within SENSAT. The sensor model has been improved by introducing a noise model for quantum detectors. It takes into account photon noise, thermal detector/preamplifier noise, and g-r and 1/f noise. In combination with a spectral band optimization with respect to the SNR an efficient tool for the radiometric analysis of IR sensor performance is presented. The comparison of model calculations in the 3-5-micro and 8-14-microm bands with experimental measurements yields excellent agreement.

Passive infrared detector based on PVDF

Passive infrared detectors may be implemented at substantially lower cost with PVDF polymer than with monocrystals. Corresponding concepts have been developed at Siemens Research Laboratories and have resulted in a prototype of a passive IR sensor for detecting people as well as for automatically activating devices at the approach of people. A new sensor concept, in which the sensor is an integral component of the optical system and the electrical circuitry, exploits the negligible cost of procuring and processing large PVDF sheets. This concept allows implementation of an efficient compensation circuit which decisively reduces dead time and sensitivity to light.