Effects of Optical Beams on MIMO Visible Light Communication Channel Characteristics

Under 5G envision, for pushing visible light communication (VLC) channel model evolution to various non-Lambertian beams, this paper introduces the typical commercial non-Lambertian beams, such as Luxeon rebel and side emitter, into the conventional analytical VLC channel model. The numerical results illustrate that the non-Lambertian beams can significantly affect the VLC channel frequency response characteristics. Compared with the traditional Lambertian beam, Side Emitter optical beam could naturally bring up to about 56.8% VLC multi input multi output channel capacity deviation, which objectively opens a new discussion dimension for enhancing VLC transmission performance.

Vehicular Channel Characterization in Urban Environment at 30 GHz considering Overtaking and Traffic Flow

To realize reliable and stable millimeter-wave (mmWave) vehicular wireless communication, the research of vehicular channel characteristics in the dense urban environment is becoming increasingly important. A comprehensive research on the channel characteristics for 30 GHz vehicular communication in the Beijing Central Business District (CBD) scenario is conducted in this paper. The self-developed high-performance ray-tracing (RT) simulator is employed to support intensive simulations. Based on simulation results, the effects of multiantenna and beam switching on the key channel parameters are analyzed, as well as the impact of different traffic flows. The results can provide theoretical and data support for the evaluation of vehicular channel characteristics and will help for the design of the vehicular communication system enabling future intelligent transportation.

Effect of channel slope and roughness on hydraulic jump in open channel flow

An experimental study is conducted on hydraulic jump characteristics for understanding the impact of slope in an open channel flume. Hydraulic jump on different channel characteristics (horizontal smooth & rough and sloping smooth & rough) were analysed. The measured characteristics of hydraulic jump with different channel roughness and different slope were compared. The results showed that the sequent depth ratio (y2/y1 ) increases with the increase in Froude number (Fr1 ) for smooth horizontal bed and horizontal rough bed. It was also observed that with an increase in Fr1 , a decrease in y2/y1 in smooth sloping bed condition and decreases for rough sloping bed. New empirical relationships were also developed with the experimental data and results were found similar with the observed hydraulic characteristics data.

Performance of multi-antenna wireless systems based on time reversal

5G wireless mobile communication system is faced with massive equipment access, information security and effective transmission is worth paying attention to. Wireless physical layer security mainly uses encryption principle to enhance the security of information transmission, while time reversal technology combines its electromagnetic characteristics and physical channel characteristics to improve the security performance of wireless communication system. In this paper, a signal transmission model of wireless multi-antenna communication system based on time reversal cavity is proposed and white Gaussian noise is introduced. The simulation results show that the space-time focusing characteristics of time reversal cavity can make the signal energy more concentrated on the target user, which can not only effectively alleviate the communication quality problems caused by multipath effect, but also ensure the security of information transmission process.

The showrunner’s skills and responsibilities in the creation and production process of fiction series in the contemporary North American television industry

Contemporary fiction TV series production in North America is characterized by the showrunner figure’s importance. This paper aims to study the concept of “showrunner” as executive-creative producer, analyze the competencies and responsibilities carried out by them during the production process of TV shows according to personal and professional factors, and examine their position within the current television market. For this purpose, a literature review on fiction TV series production and television authorship has been conducted. After this, adopting the focus of media production studies, a qualitative methodology based on in-depth personal interviews has been used, which was carried out with a selection of thirty-six significant executive producers and writers of contemporary American TV series. The findings indicate the relevance of this profile from a historical perspective, and particularly in recent years. Although there is a basic scheme of tasks developed by the showrunner in each phase of the production process, we find differences in this actuation due to personal –sex and nationality– and professional –format/gender and channel– characteristics in this industrial context. The showrunner develops an executive-creative dual profile to maintain the project’s coherence according to the established vision. Their influence over the TV series’ creative features contributes to reflection on television authorship and its attribution to this figure.

Using the electromagnetic spectrum

We consider the problem of estimating the power and position of an unknown transmitter using only observations on the received power for several sensors, without any directional information. We describe several existing propagation models, and we compute the Fisher in- formation for the free-space loss model. For more complex model, we present some results using a Markov Chain Monte Carlo method, and we describe the application of a particle filter to estimate posterior distributions for the transmitter and channel characteristics.