Space Technology

We investigate microdiversity-augmented macrodiversity techniques in wireless communication networks. The setup consists of K widely separated access ports each carrying N antennas. The conventional selection macrodiversity (Scheme I) and two proposed methods (Scheme II and Scheme III) for port selection are investigated and their performance are compared. Scheme II utilizes the advancement in distributed antennas and radio-on-fiber technologies whereas Scheme III utilizes these technologies in a way similar to the soft handover of CDMA systems. After the port selection, the microdiversity uses n strongest signals (n les N) of the selected port for diversity combining if practical constraints preclude the use of all N signals. Analytical performance expressions for the probability of error and outage probability for Scheme I are developed. Simulations are used to investigate Scheme II and Scheme III and it is observed that these latter schemes exhibit performance superiority over the conventional macrodiversity selection method. The power savings obtained using the proposed architecture and new selection schemes could be used either for coverage extension or to increase capacity in wireless networks

This paper describes an action research project based on the process of designing the visualisation of heart and breath rate data for the interactive artwork Cardiomorphologies. The project aimed to realise the affective goals of the artist as closely as possible by studying the audience experience of the visualisations and incorporating the findings into an iterative design process. The qualities of richness and ambiguity were found to contribute to the achievement of the artists' two major aims: 1) to create a sense of ...

Today, many knowledge-based technology applications form a business ecosystem: a set of complex products and services made by multiple firms in which no firm is dominant. For this paper the emerging radio frequency ID (RFID) ecosystem was built based on firms' alliance announcements, and propositions around the behavior of large, multi-line technology firms in this network were analyzed. The RFID network is used to empirically show that absorptive capacity, and exploration vs. exploitation theories may explain some behavior of large firms. Specifically, a propensity to form alliances in general makes it more likely large firms will join the RFID ecosystem, and more exploratory firms join earlier. Greater availability of slack resources also leads to the formation of more alliances in the network. The ecosystem perspective and these results may influence alliance decisions of firms entering into high cost technological innovations.

Nigeria is a nation who abandoned agriculture for oil earnings. This action resulted in food exports and thus food insecurity in the country. Agriculture has been the main source of foreign earnings for the nation before the discovery of oil, and can still be if enough attention is paid to the sector. One of the crops that can eradicate food insecurity in Nigeria and also earn foreign exchange is cassava. Cassava is the most consumed crop in Nigeria, and a crop whose products can be exported for foreign earnings. The Obasanjo government revived agriculture in Nigeria and especially paid attention to cassava cultivation for both national and international consumption; it also initiated and promoted the importance of space technology to economic development. NigeriaSat-1, a Nigeriansatellite has a lot of application areas, one of which is precision agriculture. As part of the effort to increase cassava production in Nigeria, the use of space tools (use of NigeriaSat-1 images and other satellite images) has been considered and adopted. This paper is on predicting cassava yield using NigeriaSat-1 images to create a land use/cover map on an eight hectares cassava farm in Kwali local government of the Federal Capital Territory of Nigeria.

A coding theory approach to error control in redundant residue number systems (RRNSs) is presented. The concepts of Hamming weight, minimum distance, weight distribution, and error detection and correction capabilities in redundant residue number systems are introduced. The necessary and sufficient conditions for the desired error control capability are derived from the minimum distance point of view. Closed-form expressions are

Three-dimensional sound's effectiveness in virtual reality (VR) environments has been widely studied. However, due to the big differences between VR and augmented reality (AR) systems in registration, calibration, perceptual difference of immersiveness, navigation, and localization, it is important to develop new approaches to seamlessly register virtual 3-D sound in AR environments and conduct studies on 3-D sound's effectiveness in AR context. In this paper, we design two experimental AR environments to study the effectiveness of 3-D sound both quantitatively and qualitatively. Two different tracking methods are applied to retrieve the 3-D position of virtual sound sources in each experiment. We examine the impacts of 3-D sound on improving depth perception and shortening task completion time. We also investigate its impacts on immersive and realistic perception, different spatial objects identification, and subjective feeling of "human presence and collaboration". Our studies show that applying 3-D sound is an effective way to complement visual AR environments. It helps depth perception and task performance, and facilitates collaborations between users. Moreover, it enables a more realistic environment and more immersive feeling of being inside the AR environment by both visual and auditory means. In order to make full use of the intensity cues provided by 3-D sound, a process to scale the intensity difference of 3-D sound at different depths is designed to cater small AR environments. The user study results show that the scaled 3-D sound significantly increases the accuracy of depth judgments and shortens the searching task completion time. This method provides a necessary foundation for implementing 3-D sound in small AR environments. Our user study results also show that this process does not degrade the intuitiveness and realism of an augmented audio reality environment

– In this paper, we will provide an overview of the mechanisms used in image protection, especially Chaos-based encryption techniques available today. We will see how previously proposed methods such as Data Encryption Standard (DES), Triple Data ...

This paper describes how to use a positive deviance-inspired process for improving the practice of systems engineering, and how positive deviance fits into an evolutionary improvement strategy. It illustrates the process with examples from both systems engineering and cases studies outside of systems engineering. In particular we cite the experience of the team that authored the DoD systems engineering guide for systems of systems (SoS) [Ref 1]. They developed a representation of how successful SoS engineering practitioners view and do systems engineering that is substantially different from their individual system counterparts. The cases outside of systems engineering relate to an antistarvation program in rural Vietnam and a 150-year old problem of inadequate hand scrubbing and infections in hospitals [Ref 2]. Even with substantial progress in technology, processes, and efficiencies, complex problems from enterprise systems engineering to nutrition to medical needs still stubbornly resist improvement. By using a positive deviance-inspired approach, this can be reversed.

NASA OSTEM Internship (Summer 2021) Abstract

Category: Space Technology Mission Directorate (STMD), Software Engineering Division

Development of MIPI Camera Interface Prototype Adapter Board
Haruka Kido1, Alessandro Geist2, Cody Brewer3
1University of North Dakota, Department of Electrical Engineering, 243 Centennial Drive, Grand Forks, ND 58202
2,3Data Processing Branch, NASA GSFC, Code 587, 8800 Greenbelt Road, Greenbelt, MD 20771

This project is the development of the prototype FPGA (Field Programmable Gate Array)-Compatible MIPI CSI-2 (Camera Serial Interface) D-PHY adapter board. The FPGA used on the SpaceCube processor card does not have I/O that natively supports the D-PHY standard, and thus requires additional external components to adapt the interface to the FPGAs I/O. The goal of this project is to develop a prototype board with this external circuitry. The project tasks include 1) preliminary research and analysis of the adapter circuit requirements involving waveform comparisons, 2) signal processing chain tests for voltage measurements, 3) calculations from I/O channel system simulations in TI-TINA, 4) components’ values and circuit configuration verifications, 5) protoboard schematic entry, 6) both PCB footprint builds and PCB layout in Altium Designer, and lastly, 7) PCB manufacturing. The project requires the applications of fundamental electrical engineering laws such as Ohm’s Law and Kirchhoff’s Voltage Law for calculations of components’ values and signal analysis concepts to build the architecture of the prototype PCB during the iterative development process. The completed PCB shows the 3 receiver networks with confirmed values from the circuit simulations and waveform analyses, the 2 connectors with I/O pin reconfigurations, and both the differential trace pairs and single traces between the components and connectors. The trace routes are subjected to Altium’s rules, which enable efficient use of routing parameters for signal integrity. This adapter board is useful in data conversion and transmission from the MIPI camera module to the FPGA, a D-PHY circuit arrangement used in NASA’s SpaceCube Mini’s VADIR (Versatile Analog/Digital Interface) between the MIPI Camera module and the Backplane Connector. Once the adapter board PCB is fabricated and assembled, it can be used to demonstrate the validity of the circuit design prior to it being incorporated into the VADIR flight board design.

Over the next decades, NASA's planned solar system exploration missions are targeting planets, moons and small bodies, where spacecraft would be expected to encounter diverse extreme environmental (EE) conditions throughout their mission phases. These EE conditions are often coupled. For instance, near the surface of Venus and in the deep atmospheres of giant planets, probes would experience high temperatures and pressures. In the Jovian system low temperatures are coupled with high radiation. Other environments include thermal cycling, and corrosion. Mission operations could also introduce extreme conditions, due to atmospheric entry heat flux and deceleration. Some of these EE conditions are not unique to space missions; they can be encountered by terrestrial assets from the fields of defense, oil and gas, aerospace, and automotive industries. In this paper we outline the findings of NASA's Extreme Environments Study Team, including discussions on state of the art and emerging capabilities related to environmental protection, tolerance and operations in EEs. We will also highlight cross cutting EE mitigation technologies, for example, between high g-load tolerant impactors for Europa and instrumented projectiles on Earth; high temperature electronics sensors on Jupiter deep probes and sensors inside jet engines; and pressure vessel technologies for Venus probes and sea bottom monitors. We will argue that synergistic development programs between these fields could be highly beneficial and cost effective for the various agencies and industries. Some of these environments, however, are specific to space and thus the related technology developments should be spearheaded by NASA with collaboration from industry and academia.

On the extreme Southern Edge of Orange County California, amongst the rolling grass covered hills and wooded canyons of Rancho Mission Viejo, lies a little known complex of plain nondescript buildings and large steel framed structures – known for decades as the Capistrano Test Site


In early 2010, an historical evaluation of the test site found that 11 buildings and structures associated with development of the Lunar Module Descent Engines qualify as important resources under the California Environmental Quality Act.  These features were used in the testing and development of the Lunar-Module Descent Engines from 1964 to the end of the Apollo Program in 1972

Agriculture is one of the sectors mostly affected by climate change. Nigerian farmers have been losing their harvests to the impacts of climate change leading to lower crop production and poorer livelihoods. Climate Smart Agriculture (CSA) is an adaptation strategy that helps rural farmers to be resilient to and cope with the effects of climate change. It can be improved through the use of space technology by empowering key actors, providing them with reliable weather fore- casts at the right time.
This paper presents an assessment of already adopted space applications in Nigerian agricultural sector; the distribution of mobile phones to rural farmers by government for easy access to CSA information from extension workers. It is also a policy research on other unpractised space applications, especially the conversion of geo-data to relevant information on climate and hazards that can help local farmers, nourishing them with timely agricultural advice which enables them to have higher crop yields and a more efficient use of seeds, water and fertilizers. The farmers will also receive early warnings for drought, flooding and/or diseases on their mobile phones, thus maximizing its use. The results of this paper will be useful for crop production agencies and NGOs in Nigeria and Sub-Saharan Africa.