Project and Report (M.S.)--Virginia Polytechnic Institute and State University. M.S. 1992. / Vita. Abstract. Includes bibliographical references (leaves 109-111). Also available via the Internet.

<p>This report presents the design of a ground station for performing satellite communications using amateur radio satellites. The resulting design integrates commercially available hardware and software to provide effective communications using all current amateur satellite analog and digital operating modes. The station is capable of growth to support message forwarding, gateway, and satellite monitoring and control functions. The acquisition plan spreads the station's acquisition over several years to keep costs within an individual's budget, and maintains flexibility to adapt to changes in satellites and communications modes available over the station's life. The station's major design drivers are sufficient link budget for reliable communications, the station's life cycle cost, ensuring radio frequency energy fields are at safe levels, placement of antennas and supports to comply with local architectural restrictions, and selection of a 435 MHz transceiver for the station.</p> <p>This project illustrates the ability of individuals or small groups to economically acquire effective satellite communications capability by integrating largely off-the-shelf hardware and software. In conjunction with small, relatively low-cost satellites, this ability places space communications and related research within reach of groups otherwise excluded from participating in satellite programs.</p> / Master of Science

Thesis (M.S.)--Boston University / PLEASE NOTE: Boston University Libraries did not receive an Authorization To Manage form for this thesis or dissertation. It is therefore not openly accessible, though it may be available by request. If you are the author or principal advisor of this work and would like to request open access for it, please contact us at open-help@bu.edu. Thank you. / 2031-01-01

International Telemetering Conference Proceedings / October 21, 2002 / Town & Country Hotel and Conference Center, San Diego, California / A telemetry system has been developed at the University of Arizona to serve as a baseline for future CubeSat designs. Two satellites are scheduled for launch in November of 2002. One features a beacon that operates autonomously of all but the power system and can independently deploy the antennas. The other will test the performance of new semiconductor devices in low earth orbit. Sensors will monitor voltages, currents (from which attitude and tumble rate can be derived), received signal strength and a distribution of temperatures. The CubeSat’s architecture, operating system, sensors, telemetry format and link budget are discussed.

Thesis (Ph. D.)--University of Hawaii at Manoa, 1981. / Bibliography: leaves [159]-162. / Microfiche. / ix, 162 leaves, bound 28 cm

The Automatic Packet Reporting System (APRS) is an amateur radio packet network that has evolved over the last several decades in tandem with, and then arguably beyond, the lifetime of other VHF/UHF amateur packet networks, to the point where it is one of very few packet networks left on the amateur VHF/UHF bands. This is proving to be problematic due to the loss of institutional knowledge as older amateur radio operators who designed and built APRS and other AX.25-based packet networks abandon the hobby or pass away. The purpose of this document is to collect and curate a sufficient body of knowledge to ensure the continued usefulness of the APRS network, and re-examining the engineering decisions made during the network’s evolution to look for possible improvements and identify deficiencies in documentation of the existing network.

Amateur Packet Radio Networking presently uses the NET/ROM protocol to establish the network. NET/ROM is considered to be insufficient to support the expected growth of the network. This research work proposes to use the TCP/IP protocol suite instead to build the network. A comparison between features of both protocols supports this proposal. A new and simple hardware platform is introduced. This will provide adequate support for initial experiments. Design considerations for both hardware architecture and software architecture are discussed in detail. Implementation of the IP protocol used for routing is discussed. / Graduation date: 1992

This thesis presents the design, simulation and analysis of a new network based on the Automatic Packet Reporting System (APRS) concept to enhance communications of CubeSat. Created in the 1980s, APRS is arguably one of the world’s largest Radio Frequency (RF) networks maintained by a community of licensed amateur radio volunteers for a variety of terrestrial purposes. Using these established nodes we can create a virtualized ground station network for satellite downlinks. Based on literature reviews of CubeSat communications systems and their orbital elements, as well as direct surveys of the amateur radio community, comprehensive far-field antenna models were created in 4nec2 for both the ground and space sections of the CubeSat downlink. The ground station antenna models include: a directional AMSAT/OSCAR Yagi-Uda, an omnidirectional J-pole, ground plane, and a whip antenna. The CubeSat antenna models used include dipoles, monopoles, and turnstiles. These models were evaluated and then imported into the Analytical Graphics Inc (AGI) Systems Tool Kit (STK) to form a discrete event simulation based on nonhomogeneous WGS84 location data extracted from real world APRS Internet Gateway (I-Gate) packets. All objects within the simulation use realistic antenna models, node locations, propagation models and satellite orbital mechanics. This simulation can act as a suite of generally applicable example satellites models (ExampleSat) for analytical comparisons that include link budgets, access times, differing data rates, antenna designs, orbital altitudes and ground station locations. Furthermore, it represents a North American continental scale RF satellite communications downlink network model. Using the virtual ground station network alters the net probability distribution of the received signal from the spacecraft. Specifically, the thesis compares non-stationary time series analysis methods upon the net received signal. The virtualized ground station network enables the aggregated received signal to appear stationary. This in turn may allow for alternative signals analysis techniques to improve a CubeSat’s downlink performance. The simulation allows us to generate representative received signals from ExampleSat to the ground station nodes for exploratory analysis, utilizing less arbitrary assumptions. This simulation and the set of models enable a more rapid start to trade-off studies for link budget design. This set of ExampleSat downlink models can be used by new designers of small-satellite communications systems. / February 2017

My thesis's topic is radio and its influence on society in the First Czechoslovak Republic. The topic of this thesis is approached form a perspective of history of technology. This historical discipline is most widely used within the Western Europe, especially in the Netherlands. The history of technology pays attention to the technology not from excessively technological view, but rather from sociological and cultural view. One of main interests of this historical discipline, lies in the scientists, whose work led to the discovery and technological progress. In my thesis, I will first of all pay attention to the radio as a technological phenomenon. I am going to try to present a new interpretation of the radio. Main interest of this thesis, is going to be technological development of radio from its conception to the spread of this technology, political discussions within the parliament and cultural reflections of this new technology. Key words: radio, history of technology, Czechoslovakia, technology, amateur radio operator, HAM Radio

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