The phase of the crosspolarized signal generated by millimeter wave propagation through rain

Proposed schemes for cancelling rain-induced crosstalk in dual-polarized communications systems depend upon the phase relationships between the wanted and unwanted signals. This report investigates the phase relationship of the rain-generated crosspolarized signal relative to the copolarized signal. Theoretical results obtained from a commonly accepted propagation model are presented. Experimental data from the Communications Technology Satellite beacon and from the Comstar beacon are presented and the correlation between theory and data is discussed. An inexpensive semi-adaptive cancellation system is proposed and its performance expectations are presented. The implications of phase variations on a cancellation system are also discussed

ACTS and OLYMPUS propagation experiments

The OLYMPUS and ACTS satellites both provide opportunities for 10 to 30 GHz propagation measurements. The spacecraft are sufficiently alike that OLYMPUS can be used to test some prototype ACTS equipment and experiments. Data are particularly needed on short term signal behavior and in support of uplink power control and adaptive forward error correction (FEC) techniques. The Virginia Tech Satellite Communications Group has proposed a set of OLYMPUS experiments including attenuation and fade rate measurements, data communications, uplink power control, rain scatter interference, and small-scale site diversity operation. A digital signal processing receiver for the OLYMPUS and ACTS beacon signals is being developed

Book review: reconstructing democracy: how citizens are building from the ground up by Charles Taylor, Patricia Nanz and Madeleine Beaubien Taylor

In Reconstructing Democracy: How Citizens are Building from the Ground Up, Charles Taylor, Patricia Nanz and Madeleine Beaubien Taylor respond to the lack of public faith in the institutions of representative democracy by calling for a ‘bottom-up’ reconstruction of democracy at the local level, drawing on examples of local participatory democracy in action. While the book explores some inspiring initiatives that can have real and lasting benefits for communities and the capacity to solve local problems, Luke Bostian is unconvinced that such programmes alone can address the wider structural forces that jeopardise efforts to reconstruct democracy

Video for All: An Argument Towards Standardization Of Video Production Practices and Research

Instructional videos, a subset of video pedagogy, are becoming valuable pedagogical tools for instructors within both higher education and professional writing environments. By researching contemporary academic literature and creating video artifacts that put theory into practice, this capstone project answers three important questions: 1) How could video pedagogy shift student attitudes or engagement with course content in digital learning environments? 2) What benefits and limitations of standardizing and researching video pedagogy are valuable for educators interested in creating video to understand, including educators with limited or no video production experience? 3) In what ways could certain production techniques in video pedagogy applicable to classroom settings transfer to certain professional writing contexts such as non-profit awareness campaigns or digital marketing contexts

Project Emerald: Designing a Language to be Fun

I designed the language described here to be, first and foremost, fun. I wanted it to be a programmer\u27s go-to language, the language that you pick up for personal projects or utilities. I felt the way to make this happen was to make it fun to write in. In order to accomplish this, the language derives from several existing languages, taking what I believed were the best parts of each of them. Combining principles from multiple languages sounds like a good idea, I quickly ran into problems that would make developing a compiler extremely difficult, if not impossible. Because of this, I had to make choices between certain features. Therefore, this language is not exactly how I originally envisioned it; it represents, rather, my compromise between functionality and the compiler

Project Emerald: Designing a Language to be Fun

For a computer language to be fun, it needs to be flexible, powerful, and easy to use. Emerald is a compromise between all of these features

Effect of Paragraph Indention and Spacing on Reading Speed and Comprehension

Traditionally, newspapers and magazines have indicated paragraphing by indenting

Training Extension Staff With Pre-Developed Resources

What good does a teaching and research program do in training people in information and communication? Let\u27s start with what you have to work with

Exploring Electrochemical Reactivity in Ionically-Gated Field Effect Transistors

Electric double layer gated field effect transistors (EDL FETs) are devices commonly used to investigate the fundamental properties of new materials, such as two-dimensional (2D) layered materials. Despite this usefulness and further potential for integration into devices and circuits, EDL FETs have the possibility of undergoing electrochemical reactions during device operation. Most often, this electrochemistry goes unmonitored. Part of the challenge of detecting electrochemical reactivity within EDL FETs resides in a knowledge gap between the device and analytical electrochemistry communities; that is, what type of reference electrode should be used, how should one be used, and what does it mean to monitor one? This work addresses this issue by introducing a silver metal quasi-reference electrode in a graphene EDL FET with a solid polymer electrolyte- polyethylene oxide lithium perchlorate (PEO:LiClO4)- serving as the ion-conducting dielectric. The hypothesis was that Li+ ion intercalation in graphene would drive irreversible changes to device transfer characteristics and be detectable by reference electrode monitoring. The reference electrode was used in two experiments in which the gate window of an EDL FET device was either increased with each measurement (starting from -2.5 V ≤ VSG ≤ 2.5 V and expanding to -2.5 V ≤ VSG ≤ 10 V) or fixed (-2.5 V ≤ VSG ≤ 7 V). Changes to the transfer characteristics of the devices after each experiment- an increase in average drain current, Dirac points shifted negative vs. VSG in both forward and reverse transfer sweeps, an increased ON/OFF ratio, and higher-sloped side-gate current shifted negative vs. VSG- were noted as possible evidence of electrochemical reactivity within the graphene channels. However, thanks to the Ag/Ag+ reference electrode, the data from these experiments provide evidence that intercalation of Li+ in graphene was highly unlikely. Possible alternative explanations will be discussed, including reduction of water, PMMA, and graphene oxide defects