Search results for "Signal"
showing 10 items of 6924 documents
Pattern image enhancement by extended depth of field
2014
International audience
Acoustic Topological Circuitry in Square and Rectangular Phononic Crystals
2021
International audience; We systematically engineer a series of square and rectangular phononic crystals to create experimental realizations of complex topological phononic circuits. The exotic topological transport observed is wholly reliant upon the underlying structure which must belong to either a square or rectangular lattice system and not to any hexagonal-based structure. The phononic system chosen consists of a periodic array of square steel bars which partitions acoustic waves in water over a broadband range of frequencies (∼0.5MHz). An ultrasonic transducer launches an acoustic pulse which propagates along a domain wall, before encountering a nodal point, from which the acoustic si…
Target 5G visible light positioning signal subcarrier extraction method using particle swarm optimization algorithm
2021
International audience; With the explosive growth of demand for Internet of Things (IoT) applications and the increasing dependence of users on wireless connections, indoor location based service(LBS) under 5G-Public-Private Partnership (5G-PPP) using cases have received more attention and get rapid development. Thanks to the safty, security and customization of 5G network pointed by 5G forum white paper, indoor positioning systems using unified 5G New Radio (NR) signals have become the focus of the next generation of visible light positioning (VLP) systems. In 5G New Radio(NR) frame, totally 192 subcarriers are used to carry positioning reference signal(PRS). In order to improve the positi…
On improving the accuracy of Visible Light Positioning system based PAPR reduction schemes
2020
International audience; DC-biased optical Orthogonal Frequency Division Multiplexing (DCO-OFDM)-based visible light positioning (VLP) technology along with the Received Signal Strength(RSS) positioning algorithm is widely used to achieve centimeter level positioning accuracy for incoming 5G era, especially indoor environment. However, the DCO-OFDM has the peak-to-average power ratio (PAPR) issue which imposes the nonlinear distortion and it will directly affect the positioning accuracy in the VLP system. The PAPR reduction scheme is urgently needed. Therefore , in this paper, the impact of PAPR reduction scheme on positioning accuracy is investigated. The positioning accuracy with and witho…
METHOD AND DEVICE FOR DETERMINING THE POSITION AND ORIENTATION OF A SPECULAR SURFACE FORMING A DIOPTER
2018
Visual and acoustic techniques for motorcycle collision warning system with EEG validation
2018
In many countries, motorcyclist fatality rate is much higher than that of other vehicle drivers. Among many other factors, motorcycle rear-end collisions are also contributing to these biker fatalities. Collision detection systems can be used to minimize these fatalities. However, most of the existing collision detection systems do not identify the type of potential hazard faced by motorcyclists. Every collision warning system used a distinctive collision detection technique, which limits its performance and makes it imperative to study its effectiveness. Unfortunately, no such work has been reported in that particular domain for motorcyclists. Therefore, it is important to study the physio…
Equivalence of Open-Loop and Closed-Loop Operation of SAW Resonators and Delay Lines
2019
International audience; Surface acoustic wave (SAW) sensors in the form of two-port resonators or delay lines are widely used in various fields of application. The readout of such sensors is achieved by electronic systems operating either in an open-loop or in a closed-loop configuration. The mode of operation of the sensor system is usually chosen based on requirements like, e.g., bandwidth, dynamic range, linearity, costs, and immunity against environmental influences. Because the limit of detection (LOD) at the output of a sensor system is often one of the most important figures of merit, both readout structures, i.e., open-loop and closed-loop systems, are analyzed in terms of the minim…
Electrophysiological Effects of Direct Electrical Stimulations During Awake Brain Surgery: Methodological Considerations
2015
International audience; IRECT electrical stimulation (DES) has long been used to perform real-time functional mapping of the brain. More recently, this technique was introduced in the neurosurgery of slow-growing and infiltrative brain tumors to guide the resection with great success. By generating transient perturbations, this method allows the real-time identification of both cortical areas and subcortical networks that are essential for the function. Thus, as much as possible, non-functional tissue can be removed while minimizing the sequelae. However, the understanding of the electrophysiological effects of DES and, in particular its remote propagation, remains an open and key question.…