Improving ROCs of Constant False Alarm Coded Anti-collision Radar in very noised cases

The use of Constant False Alarm Coded Anticollision Radar (CFACAR) is very interesting in automotive environment. Due to the orthogonality properties of used codes this system is most robust to multi-user interferences. The actual version of the receiver called in this paper Single Correlation Receiver (SCR), is not able to detect the targets in very low input Signal to Noise Ratio (SNR). To resolve this problem, we present a new receiver called Averaging Correlation Receiver (ACR), that computes the average of the M later correlations.Then, we developed the expression of detection and false alarm probabilities for the new receiver in mono and multi-user scenarios. These probabilities are used to plot the new Receiver Operating Characteristics (ROCs). They are drawn for different values of input SNR and length M of ACR. There is a suitable value of M, according to some equation, that can be taken to have a good detection (ROCs more perfect). Also, we found that for a fixed SNR, we must increase sufficiently the length M but it is possible only for low relative velocity of the target. For a velocity of 5Km=h with M = 1055, we can lessen the value of the SNR until we reach SNR = -45 dB

Radar positioning system accuracy test

"The U.S. Bureau of Mines conducted research to develop an accurate, real-time, position monitoring and warning system for the vehicles used in surface mining. This research was conducted in preparation for development of an accurate, real-time position monitoring and warning system, which notifies equipment operators when they deviate from a known safe course and are approaching a fixed hazard. A radar positioning system designed for marine applications was evaluated and a series of tests was run to determine the accuracy of the radar positioning system when used in a land vehicle. The radar position determination was compared to surveyed values. Both static and dynamic (moving vehicle) tests were conducted. The static test results were marginal and the dynamic test results were not accurate enough for the position monitoring and warning system." - NIOSHTIC-2NIOSHTIC no. 10012552199

Performance Analysis of Radar Based on Ds-BPSK Modulation Technique”,

ABSTRACT Radar (Radio Detection and Ranging) systems are widely used now-a-days as automotive radar for Intelligent Transport System (ITS). In this paper we mainly focus on analyzing the performance short distance radar based on spread spectrum technology. Spread spectrum modulation technique is chosen as it has some significant properties like accuracy of ranging, sensitivity, accuracy of power-estimation, interference suppression etc. The system is implemented in Matlab/Simulink

Sensor-based management systems based on RFID technology

Παρατηρήσεις έκδοσης: λείπουν οι σελίδες 78, 102 από το φυσικό τεκμήριο.In this diploma thesis, the RFID technology is analyzed (operating principles, readers' and tags hardware, coding, modulation, anticollision procedures, frequencies, standards, applications). Moreover, a protocol to synchronize readers working in a multi-reader multi-tag environment is proposed. The protocol is applied to the store shelf scanning application and further refined to meet the requirements of this specific application

Application of radar for automotive collision avoidance. Volume 1: Technical report

The purpose of this project was research and development of an automobile collision avoidance radar system. The major finding was that the application of radar to the automobile collision avoidance problem deserves continued research even though the specific approach investigated in this effort did not perform adequately in its angle measurement capability. Additional findings were that: (1) preliminary performance requirements of a candidate radar system are not unreasonable; (2) the number and severity of traffic accidents could be reduced by using a collision avoidance radar system which observes a fairly wide (at least + or - 10 deg) field of view ahead of the vehicle; (3) the health radiation hazards of a probable radar design are not significant even when a large number of radar-equipped vehicles are considered; (4) effects of inclement weather on radar operation can be accommodated in most cases; (5) the phase monopulse radar technique as implemented demonstrated inferior angle measurement performance which warrants the recommendation of investigating alternative radar techniques; and (6) extended target and multipath effects, which presumably distort the amplitude and phase distribution across the antenna aperture, are responsible for the observed inadequate phase monopulse radar performance

Broadband vehicle-to-vehicle communication using an extended autonomous cruise control sensor

For several years road vehicle autonomous cruise control (ACC) systems as well as anti-collision radar have been developed. Several manufacturers currently sell this equipment. The current generation of ACC sensors only track the first preceding vehicle to deduce its speed and position. These data are then used to compute, manage and optimize a safety distance between vehicles, thus providing some assistance to car drivers. However, in real conditions, to elaborate and update a real time driving solution, car drivers use information about speed and position of preceding and following vehicles. This information is essentially perceived using the driver's eyes, binocular stereoscopic vision performed through the windscreens and rear-view mirrors. Furthermore, within a line of vehicles, the frontal road perception of the first vehicle is very particular and highly significant. Currently, all these available data remain strictly on-board the vehicle that has captured the perception information and performed these measurements. To get the maximum effectiveness of all these approaches, we propose that this information be shared in real time with the following vehicles, within the convoy. On the basis of these considerations, this paper technically explores a cost-effective solution to extend the basic ACC sensor function in order to simultaneously provide a vehicle-to-vehicle radio link. This millimetre wave radio link transmits relevant broadband perception data (video, localization...) to following vehicles, along the line of vehicles. The propagation path between the vehicles uses essentially grazing angles of incidence of signals over the road surface including millimetre wave paths beneath the cars

Aeronautical Engineering: A continuing bibliography with indexes, supplement 155, December 1982

This bibliography lists 272 reports, articles and other documents introduced into the NASA scientific and technical information system in November 1982

Évaluation de la performance des capteurs véhiculaires pour la détection des usagers vulnérables

RÉSUMÉ : L’automatisation graduelle des véhicules repose sur les systèmes d’aide à la conduite. Ces systèmes se basent sur les données de différents capteurs embarqués permettant de percevoir l’environnement et prendre une décision en cas de danger. Dans ce cadre s’articule ce présent projet qui vise à évaluer des capteurs de détection des usagers de la route (véhicule, piéton et cycliste) et d’obstacles. Bien que de nombreuses études d’évaluation des systèmes de détection ont été réalisées dans la littérature, ce sujet reste un défi. Ces études se concentrent sur l’évaluation d’un système composé de différents capteurs fusionnés. Cependant, ce travail évalue la performance des capteurs de manière indépendante. Cette étude vise à déterminer l’efficacité de ces dispositifs destinés à aider les conducteurs à éviter les collisions avec les usagers vulnérables et autres obstacles. Ce présent rapport présente le choix et l’intégration des capteurs véhiculaires, la réalisation de l’expérimentation et la collecte de données dans la ville de Montréal. Les capteurs de détection en question sont un lidar à état stable (solide state) et des caméras de bord (dashcams) qui permettent de détecter les usagers de la route à proximité du véhicule. ’identification des interactions se repose sur des scénarios statiques et dynamiques. Les scénarios statiques étudiés visent à examiner l’efficacité de lidar à la détection d’un piéton et d’un cône de signalisation. Par la suite, une analyse exploratrice a été réalisée pour chaque scénario. Les prédictions ont été extraites en identifiant les données atypiques (les mesures aberrantes) dans l’ensemble de données. La matrice de confusion a été générée en comparant les annotations manuelles et les prédictions. Le rappel du lidar avec l’approche de classification établie est 85,5 %. Nous analysons par la suite la performance sur la mesure de la distance pour le piéton et le cône en test statique. Nous avons calculé l’erreur moyenne absolue et le taux des mesures de la distance dans l’intervalle de tolérance 0,3 quand le piéton, ou le cône existent réellement dans le champ de vision du lidar avec des prédictions qui indiquent l’existence de ces détections. D’une façon générale, nous constatons que l’erreur ne dépasse pas 2,6 m pour tous les segments sauf le segment 12 qui a une erreur de 7,12 m. Mais, le taux des mesures de la distance dans l’intervalle de tolérance ne dépasse pas 52 %. Pour l’étude dynamique, deux expériences ont été réalisées au centre de l’île de Montréal en hiver. La première expérience a duré plus que 2 heures à la fin de la semaine. La deuxième expérience a duré plus que 3 heures au milieu de la semaine. Des interactions avec les types d’usagers (voiture, piéton, cycliste) ont été analysées à partir des données collectées depuis le lidar. Pour les scénarios étudiés, les détections coïncident entre les segments voisins. Finalement, les caméras de bord sont incapables de détecter les usagers vulnérables avec une vitesse inférieure à 50 km/h. Nous constatons que les caméras Garmin 66 w et Thinkware Q800 ne sont pas destiné pour la détection des usagers vulnérables au milieu urbain.----------ABSTRACT : Advanced driver assistance systems are based on various sensors, which record data and detect vulnerable road users. In that context, this project aims to evaluate obstacle and road user detection sensors through the study of interactions between road users. Numerous studies evaluating obstacle detection systems have been carried out in the literature. These studies focus on the evaluation of the fusion of different sensors. However, this work evaluates the performance of sensors independently. This report presents the steps of the choice and the integration of vehicle sensors, the implementation of the experiment, and the data collection by circulating in dangerous zones in the city of Montreal. The detection sensors in question are a solid-state lidar and dashcams which detect road users near the vehicle. The identification of interactions is based on static and dynamic scenarios. The static scenarios studied aim to examine the effectiveness of lidar in detecting a pedestrian and a traffic cone. After extracting the observations corresponding to the areas of interest, an exploratory analysis was carried out for each scenario. Objects of interest were extracted by identifying outliers. Confusion matrix was generated by comparing the actual and estimated detections. In static scenarios, the lidar recall with the studied approach is 85.5%. Then, we analyze the performance on the measurement of the distance for the pedestrian and the cone in static test. The mean absolute error and the rate of the measurements of the distance on the tolerance range of 0,3 m were calculated when the pedestrian and the traffic cone exist in the field of view of the lidar and the predictions detect their presence. In general, the error does not exceed 2,6 m for all segments except segment 12 which has an error of 7,12 m. However, the rate of the measurements on the tolerance range do not exceed 52%. For the dynamic study, two experiments were carried out in the center of the island of Montreal in winter. The first experience lasted more than two hours at the end of the week. The second experiment lasted more than three hours in the middle of the week. Interactions with the types of users (car, pedestrian, cyclist) were analyzed from the observations of lidar. We notice a strong consistency in the distance to the object of interest between the neighboring segments. Finally, dashcams are not able to detect vulnerable users with speed below 50 km/h. Dashcams Garmin 66 W and Thinkware Q800 are not intended for the detection of vulnerable users in urban areas