Engineering Commons^™

Cubesat Data Transmission And Storage Throughput Optimization Through The Use Of A Zynq Soc Based Cubesat Science Instrument Interface Electronics Board, Caleb Mosby Munsill

Master's Theses

The CubeSat standard sprang from the desire to create a satellite standard that would open the doors for universities and other lower budget research institutions by making it more feasible to get their work into space. Since then, many other institutions and industries have been adopting variations on the standard for their own use. As more people are seeking out to use the CubeSat standard as their main bus, the standards and practices of the community have grown and expanded and with this growth, new challenges have been created. One such challenge is the bandwidth limitation in the RF-downlink. When …

Ism S-Band Cubesat Radio Designed For The Polysat System Board, Craig Lee Francis

Master's Theses

Cal Poly’s PolySat CubeSat satellites have begun to conduct more complex and scientifically significant experiments. The large data products generated by these missions demonstrate the necessity for higher data rate communication than currently provided by the PolySat UHF radio. This thesis leverages the proliferation of consumer wireless monolithic transceivers to develop a 250kbps to 2000kbps, 2W CubeSat radio operating within the 2.45GHz Industrial, Scientific, and Medical (ISM) radio band.

Estimating a link budget for a realistic CubeSat leads to the conclusion that this system will require a large deployable CubeSat antenna, large earth station satellite dish, and a fine-pointing attitude …

Dual High-Voltage Power Supply For Use On Board A Cubesat, Nicholas Weiser

Master's Theses

Since their conception in 1999, CubeSats have come and gone a long way. The first few that went into space were more of a “proof of concept,” and were more focused on sending simple data and photographs back to Earth. Since then, vast improvements have been made by over 40 universities and private firms, and now CubeSats are beginning to look towards interplanetary travel. These small satellites could provide a cost effective means of exploring the galaxy, using off the shelf components and piggy-backing on other launch vehicles with more expensive payloads. However, CubeSats are traditionally launched into Low Earth …

A Compact, Reconfigurable Uhf Communication System Design For Use With Polysat's Embedded Linux Platform, Austin Williams

Master's Theses

The beginning of this thesis provides an overview of the heritage UHF Communication System design flown on CP2, CP3, CP4, CP5, and CP6, summarizing previous analysis of its performance, and providing the justification for a complete system re-design. High level requirements for the new UHF System are defined, and a trade study is performed on state-of-the-art single chip transceivers, low noise amplifiers, and transmit power amplifiers. These components are then designed into a functional communication system, with key components analyzed for proper impedance matching and performance characterization compared to expected datasheet values. Next, the system as a whole is characterized …

Reliable Software Updates For On-Orbit Cubesat Satellites, Sean Fitzsimmons

Master's Theses

CubeSat satellites have redefined the standard solution for conducting missions in space due to their unique form factor and cost. The harsh environment of space necessitates examining features that improve satellite robustness and ultimately extend lifetime, which is typical and vital for mission success. The CubeSat development team at Cal Poly, PolySat, has recently redefined its standard avionics platform to support more complex mission capabilities with this robustness in mind. A significant addition was the integration of the Linux operating system, which provides the flexibility to develop much more elaborate protection mechanisms within software, such as support for remote on-orbit …

Receive Sensitivity Characterization Of The Polysat Satellite Communication System, Ivan M. Bland

Master's Theses

Following the successful launch of CP3 and CP4, the PolySat team noticed an unreliable uplink to both satellites. A significant problem with the PolySat COMM system is poor receive sensitivity of the communications system. Efforts have been made to improve the uplink margin, but without proper characterization of the receiver sensitivity, the problem cannot be fully addressed. By developing an accurate method of measuring receive sensitivity, a methodical approach can be used to properly diagnose the communication system and link budget. Two revisions of the PolySat COMM system will be measured and compared. An in-depth study of the PolySat COMM …

Development Of An Imager System Optimized For Low-Power, Limited-Bandwidth Space Applications, Kalia R. Glassey

Master's Theses

A relatively new picosatellite standard, CubeSats have traditionally been used for simple educational missions. As CubeSats become more complex and utilize more complex sensors such as imagers, they gain enhanced credibility as satellite platforms.

Imaging systems on CubeSats have the potential to be used for a variety of uses, such as earth and weather monitoring, attitude determination, and remote sensing. However the size and power limitations of CubeSats pose an interesting challenge to the design of a capable, robust imaging system.

This thesis outlines the objectives and requirements of CP-3’s imaging system, and describes the development process and methods. Test …