The use of an ultra-wideband (UWB) radio technique is proposed as a viable solution for the distribution of high-definition audio/video content in fiber-to-the-home (FTTH) networks. The approach suitability is demonstrated by the transmission of standards-based UWB signals at 1.25 Gb/s along different FTTH fiber links with 25 km up to 60 km of standard single-mode fiber length in a laboratory experiment. Experimental results suggest that orthogonal frequency-division-multiplexed UWB signals exhibit better transmission performance in FFTH networks than impulse radio UWB signals.

The paper experimentally investigates the performance of the Ethernet and Fast-Ethernet free space optical (FSO) communications link under the influence of the weak atmospheric turbulence. A dedicated experimental indoor atmospheric chamber is used to generate and control the turbulence conditions that affect the FSO link performance. The chamber is calibrated and the measured data are verified with the theoretical prediction. We also demonstrate methods to control the turbulence levels and determine the equivalence between the indoor and outdoor FSO links. It is also observed that the connectivity of Ethernet and Fast-Ethernet links are highly sensitive to atmospheric conditions.

Science, Technology, Engineering, and Mathematics (STEM) are key disciplines towards tackling the challenges related to the Sustainable Development Goals. However, evidence shows that women are enrolling in these disciplines in a smaller percentage than men, especially in Engineering related fields. As stated by the United Nations Women section, increasing the number of women studying and working in STEM fields is fundamental towards achieving better solutions to the global challenges, since the potential for innovation is larger. In this paper, we present the Girls4STEM project, which started in 2019 at the Escola Tècnica Superior d’Enginyeria de la Universitat de València, Spain. This project works towards breaking the stereotypes linked to STEM fields, addressing both boys and girls aged from 6 to 18, but especially trying to open the range of career options for young girls through interaction with female STEM experts. The goal is to spark girls’ interest in STEM disciplines from childhood, so that they become more self-confident in these areas. To achieve this goal, the project is built over three main actions: the Girls4STEM Family Talks, where students, families, and teachers participate; the Girls4STEM Professional Talks, where the target is a general audience; and the Initial Training Seminars for teachers. Short-term results are here presented, showing that aspects related to self-perception and perception from others (family, teachers) play a significant role. Moreover, these results also indicate that there may not be a general understanding of which disciplines are included in STEM.

In this letter, two methods for characterizing fog attenuation in terms of atmospheric visibility V in free space optics (FSO) communications are analyzed and compared. Both methods measure the fog attenuation based on V using a charge-coupled device (CCD) camera and a laser-diode at 0.55 μm. The methods are evaluated in a laboratory controlled FSO atmospheric chamber operating at individual wavelengths of 0.83, 1.31, and 1.55 μm using a continuous optical spectrum range 0.6-1.6 μm. The CCD technique shows great accuracy for V <; 50 m and the laser technique for the range 100 m, thus allowing enhancement of the characterization of FSO links in thick and dense fog conditions. The experimental results also show a wavelength dependency for V <; 0.5 km where the attenuation decreases from 52 dB/km at visible wavelengths to 46 dB/km at near infrared wavelengths.

In this letter the performance of a free space optical (FSO) communication link in the presence of fog is experimentally investigated in an indoor environment. A dedicated indoor atmospheric chamber, replicating the outdoor environment, is being used to evaluate the FSO link performance under the fog condition. Theoretical analysis supported by the experimental evaluation has been carried out for the intensity modulation/direct detection on-off keying non-return-to-zero (OOK-NRZ), OOK return-to-zero (OOK-RZ) and four pulse position modulation (4-PPM) modulation formats at the Ethernet baseline data-rate. The results shown indicate that the 4-PPM signalling scheme is the most robust to the fog attenuation due to its high peak-to-average power ratio. Moreover, results also show the potential of the indoor atmospheric chamber to replicate outdoor atmospheric effects (such as fog) and be able to quickly characterise and assess the FSO system under a controlled environment.