14 research outputs found
Challenges in Partially-Automated Roadway Feature Mapping Using Mobile Laser Scanning and Vehicle Trajectory Data
Connected vehicle and driver's assistance applications are greatly
facilitated by Enhanced Digital Maps (EDMs) that represent roadway features
(e.g., lane edges or centerlines, stop bars). Due to the large number of
signalized intersections and miles of roadway, manual development of EDMs on a
global basis is not feasible. Mobile Terrestrial Laser Scanning (MTLS) is the
preferred data acquisition method to provide data for automated EDM
development. Such systems provide an MTLS trajectory and a point cloud for the
roadway environment. The challenge is to automatically convert these data into
an EDM. This article presents a new processing and feature extraction method,
experimental demonstration providing SAE-J2735 map messages for eleven example
intersections, and a discussion of the results that points out remaining
challenges and suggests directions for future research.Comment: 6 pages, 5 figure
Analysis and performance evaluation of the next generation wireless networks
International audienceExponential growth in demand for high bandwidth applications such as multimedia in cellular networks has triggered the need for development of new technologies capable of providing the required high bandwidth, reliable links in wireless environments. However, the available spectrum is a limited natural resource and the current technologies have been shown to have low spectrumefficiency. To improve the spectrum efficiency, heterogeneous networks are considered as a viable solution. They are composed of a mix of macro, pico, femto and relay base-stations that improve the spectrum efficiency and throughput performance of the system. The aim of this chapter is to provide an overview of these emerging technologies. This chapter describes the main characteristics and performance requirements that the next generation networks must fulfill. Particularly, the focus is on Long Term Evolution (LTE)/LTE-Advanced technologies where some possible improvements and challenges are explained. Subsequently, the analytical methods and simulations techniques to evaluate the performance of the next generation heterogeneous networks are discussed. Finally, the simulation results for some example scenarios are provided and discussed
Wireless Cognitive Networks Technologies and Protocols
International audienceSoftware Defined Radio and Cognitive Radio applied to Wireless Sensor Networks and Body Area Networks represent an intriguing and really recent paradigm, which represents an objective of study of several researchers. In order to make this technology effective, it is necessary to consider an analytical model of communication capacity, energy consumption and congestion, to effectively exploit the Software Defined Radio and Cognitive Radio in this type of systems. This chapter discusses on the analytical modeling to make this kind of technologies effective for wireless networks, by focusing on Cognitive Wireless Sensor Networks and Cognitive Wireless Body Area Networks. Moreover, we consider some routing approaches proposed for Cognitive Wireless Sensor Networks and Cognitive Wireless Body Area Networks, and evaluated by means of simulation. Finally, we address additional issues that this type of networks presents by comparing them with “traditional” routing protocols
Competition: Channel Exploration/Exploitation Based on a Thompson Sampling Approach in a Radio Cognitive Environment
International audienceMachine learning approaches have been extensively applied in interference mitigation and cognitive radio devices. In this work, we model the spectrum selection process as a multi-arm bandit problem and apply Thompson sampling, a fast and efficient algorithm, to find the best channel in the shortest time interval. The learning algorithm will work on top of a network layer to efficiently route the event information to the sink
Modelling and analysis of energy efficient wireless body area networks
This work is motivated by the challenges and shortcomings of the design and evaluation of wireless body area networks. Wireless body area network (WBAN) is an interesting application of sensor networks which can revolutionize our interaction with the outside world. Appealing applications of WBAN has attracted both academic and industrial attention. However there are some challenges that need to be addressed before such applications can come true.DOCTOR OF PHILOSOPHY (EEE
Frequency domain approach for skin artifact removal in UWB microwave breast cancer detection
75 p.Early time detection of the breast cancer will lead to a more efficient treatment and comfort of the patient. Currently the gold standard method in screening breast cancer is x-ray mammography which employs a low dose of ionizing radiation to create a high resolution image of the compressed breast. Although this method has been shown to be able to save lives, it still has shortcomings, the most important among which is the use of ionizing radiation that prevents this method to be used as a regular screening method. Hence, other modalities for the possible use in breast cancer detection has been investigated. Among them, UWB microwave pulse has been shown to be promising in detecting breast tumor while it has no known health risk for the patient. But a major problem in applying this method for breast tumor detection is the strong backscatter produced by the skin surface which can mask the weak tumor signature reflected from inside the breast medium. Several methods are proposed to solve this problem but none can effectively remove this artifact in general plus the deterioration they introduce to the tumor response. In this study a new method exploiting frequency domain information to overcome this problem is proposed. In this method the frequency response is analyzed and skin related information is removed and the time domain skin-removed signal is obtained from frequency response. Applying this method to simulated models of the breast shows that it can effectively remove the skin backscatter without introducing deterioration to the tumor response. Also the effectiveness of this method in removing the skin reflection is compared with the current methods. Results show that this algorithm can be considered as a promising method for skin artifact removal. However, more studies are needed to test the capability of this method in more realistic cases.MASTER OF ENGINEERING (EEE
Ultra-wideband real-time dynamic channel characterization and system-level modeling for radio links in body area networks
Reliable on-body wireless network design needs to incorporate the natural body movements. However, existing models are static or pseudo-dynamic models. In this work, the lack of a comprehensive channel model for a moving body is addressed. A dynamic radio channel around the human body is statistically analyzed and modeled. Important parameters of the channel are estimated from measured data and compared with the model prediction. Simulations show that the model can predict the parameters of a system working in a dynamic body area network with 92% accuracy