MCMC Methods for Realistic Indoor Wireless Optical Channels Simulation

Abstract

International audienceThis paper presents two new simulation algorithms of the optical wireless channel based on the Markov Chain Monte Carlo method. They allow to generate correlated three-dimensional light paths, keeping into account the nature of the simulation environment, taking advantage of its complexity such as transmitter and receiver position and orientation, the geometry, and the nature of the surfaces (diffuse, specular, etc.). Like Markov Chain Monte Carlo methods, these new algorithms are adaptive. They automatically do more calculation where light paths transport more power. Hence, they optimize their convergence speed, reducing the required number of paths to achieve a given accuracy threshold for the channel impulse response calculation. This paper shows that, compared to previous classical Monte Carlo solutions, these new algorithms reduce the computation time, up to a factor 225 for a fixed quality according to our experiments

Channel Characterization and Modeling for Optical Wireless Body-Area Networks

“…Lastly, [28] studied the influence of random device orientations on the statistics of the received signal-to-noise (SNR) for a mobile user. A few studies have considered channel characterization for optical WBANs in the IR band such as the work in [29], which was based on MCRT simulations using a dedicated software, called RapSor [30]. On the other hand, channel characterization for extra-WBAN links (i.e., between a CN and an AP located in the room) was considered in [31]- [34], where user mobility was considered based on uniformly distributed random user positions and orientations of the sources/detectors.…”

A Link Reliability Study of Optical Wireless Headset inside Aircraft Cockpit

“…To determine the impulse response for the different considered channels, we adopt a modeling approach based on a stochastic Monte Carlo method, associated with the ray-tracing algorithm. Our research laboratory has developed the RaPSor software (Ray Propagation Simulator), which is an open source and extensible tool, based on the Netbeans platform for modelling IR and visible links [12,13]. It allows determination of the impulse response h(t) for a defined link.…”

“…As for the cockpit and for the same reason, the reflection coefficient of the body is fixed to 0.5. All the surfaces in the scene are considered as perfectly diffuse and are consequently modeled by a Lambertian Bidirectionnal Reflectance Distribution Function (BRDF) [12].…”

Infrared and visible links for medical body sensor networks

“…It allows determining the impulse response h(t) for a defined scenario by using stochastic method of Monte Carlo, associated to ray tracing algorithm [11,14]. For all the simulations, in order to manage tradeoffs between calculation times and accuracy, we consider three reflections per optical beam, which is a classical approach for non-directed Line-Of-Sight (LOS), or diffuse transmissions.…”

“…which is an open and extensible tool, based on the Netbeans platform for the modelling of Infrared and Visible links [11]. We have also designed portable OWC devices to carry out experimental test-beds for low data rates infrared uplinks exploiting indoor diffuse reflections [12].…”