This paper presents concentrator and lens models for the detector and emitter, respectively, upon which a Monte Carlo ray-tracing algorithm allows the evaluation of impulse response on infrared (IR) wireless indoor channels. We also present computer simulation results that show the effects of concentrator FOV and reception direction on the impulse response, received optical power, and channel rms delay spread, which allow us to propose structures for angle-diversity receivers.
A conventional angle diversity receiver uses multiple receiving elements that are oriented in different directions, where each element employs its own filter and nonimaging concentrator, such as a compound parabolic concentrator (CPC) or hemispheric lens. In this paper, a study of the design of a conventional receiver structure using angle diversity that offers improved performance with respect to the infrared channel characteristics is presented. To this end, a recently proposed model for the effective signal collection area of a conventional angle diversity receiver that more closely approximates real behaviour than the ideal model is used. The inclusion of this model in a Monte Carlo ray-tracing algorithm allows us to investigate the effects of conventional receiver parameters on the main infrared channel parameters, such as path loss and rms delay spread. Furthermore, in order to determine the number of receiver elements, the outage probability and the average error probability are also considered. Based on the results, a conventional angle diversity receiver composed of seven elements is proposed, with one of them oriented towards the ceiling, and six angled at a 56°elevation with a 60°separation in azimuth. For each element, a CPC with a 50°field of view must be used.
This paper presents the design and implementation of a laboratory project for first-year Bachelor of Science undergraduates that is intended to consolidate concepts in the field of Physics. The laboratory experiment implements a plane whose inclination can be manually modified by the user (student or instructor), and contains a processing device based on a PIC 18F8722 microcontroller, which oversees the acquisition and processing of data supplied by different sensors located along the plane. This makes it possible for the kinetic parameters (speed and acceleration) associated with the descent of a ball rolling down the plane to be automatically and accurately measured. Moreover, the system has a radio communication module that allows it to send information to the students' laptops if these are equipped with another radio module. Therefore, the experiment can be performed in the laboratory by students who directly control all the process or by the teacher while the students observe the results on their own laptops. This practical experiment was implemented as part of a senior-year project by Electronics Engineering majors. The designers (students) of this project were able to see how their knowledge of Electronics can help them to implement complex applications that can be very useful to teaching activities.
Microcontrollers, analog-to-digital and digital-to-analog converters, radio beams, communications protocolsI.
This paper presents the design and implementation of a laboratory experiment for first year undergraduates of Bachelor of Science or Engineering degrees. The aim of the experiment is to consolidate concepts related to the subject of Physics. The laboratory experiment involves measuring the period and frequency of oscillation of a simple pendulum by means of an electronic device based on the PIC 18F4550 microcontroller, which handles the data acquisition and processing. The student will discover that for small angles, the period for a simple pendulum does not depend on the mass or on the initial angular displacement, but only on its length and on the value of the gravitational field strength (g), the latter being one of the parameters to be indirectly determined with this experiment.
Educational resources, edcuational experiments and microcontrollersI.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.