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Cloud computing can reduce cost significantly because businesses can share computing resources. In recent years Small and Medium Businesses (SMB) have used Cloud effectively for cost saving and for sharing IT expenses. With the success of SMBs, many perceive that the larger enterprises ought to move into Cloud environment as well. Government agency's stove-piped environments are being considered as...
The impending conclusion of the Space Shuttle Program and the Constellation Program cancellation unveiled in the FY2011 President's budget created a large void for human spaceflight capability and launch activity from the Kennedy Space Center (KSC). This void created an opportunity to re-architect the launch site to be more accommodating to the future NASA heavy lift and commercial space industry...
The recent planetary science decadal survey identified sample return from a comet as a major goal of the study of primitive solar system bodies. The survey identified a comet surface sample return mission as one of the candidates for a New Frontiers class mission. A touch-and-go (TAG) mission architecture where the spacecraft would maneuver close to the small body surface, a sampling device on the...
The antenna pointing accuracy of GEO satellites has quite a few effects on communication quality, while pointing accuracy is mainly affected by satellite orbit and attitude. This paper discusses the effect caused by satellite orbit. First, the allocation strategy of the GEO satellite control box was demonstrated in longitudinal and latitudinal position keeping respectively, and then the effect matrix...
Future large radio astronomy arrays, particularly the Square Kilometre Array (SKA), will be able to generate data at rates far higher than can be analyzed or stored affordably with current practices. This is, by definition, a "big data" problem, and requires an end-to-end solution if future radio arrays are to reach their full scientific potential. Similar data processing, transport, storage,...
NASA has an established process for documenting and disseminating lessons learned from spaceflight missions and related activities. However, independent assessments of the NASA lessons learned process conducted in 2002, 2003, and 2011 have concluded that NASA programs and projects are failing to heed and apply these lessons learned. JPL recently completed implementation of a three-pronged approach...
The theory and the applications of the marginalized particle filter (MPF) have attracted much research attention during the last decade. However, the existing MPF framework does not cover dependent process and measurement noises. This dependency is perhaps more common in practice than is acknowledged in the literature. In this article, we propose a general framework for MPF, covering both cases of...
We consider measurements from possibly zero-mean stochastic processes in a nonlinear filtering framework. This is a challenging problem, since it is only the second order properties of the measurements that bear information about the unknown state vector. The covariance function of the measurements can have both spatial and temporal correlation that depend on the state. Recently, a solution to this...
Much attention has been given to multiple input multiple output radar systems due to their potential for better performance in detection and angular resolution and measurement accuracy. However, MIMO radar's capabilities come with serious costs. These costs come in the overall system implementation and in considerations for real world applications. A hybrid system, where not all radiating elements...
Many parameters can affect the range correlation and range measurement during a spacecraft's normal range operation as well as in a space vehicle range testing environment. These parameters include the unanticipated voltage standing wave ratio (VSWR) reflection, multipath, flutter, space or hardware group delay, and ionospheric propagation delay, which can distort the amplitude and phase of the received...
The Aerospace Corporation (Aerospace) CubeSat program has designed a 10 Watt, inverse Class F Gallium Nitride (GaN) power amplifier currently installed and in use in CubeSat mobile ground stations. At 915 MHz and 2 dB compression, the amplifier has 17.0 dB of gain, 40.4 dBm output power, and 83.4% Power Added Efficiency (PAE). This amplifier was designed in Advanced Design System (ADS) with a vendor...
The Department of Defense (DoD) Space Test Program (STP) was created in 1965 to provide access to space for DoD research and development activities. STP provides spaceflight opportunities for payloads vetted through the DoD Space Experiments Review Board (SERB). Small spacecraft acquisition is one of STP's key areas of excellence; it is a key aspect to the program that enables the program to fly multi-payload...
Current plans call for two separate missions to deploy Medipix2-Technology-based detectors in space for the first time.1 2 NASA is planning to deploy 5 or more Radiation Environment Monitor (REM) units, each of which will contain a Medipix2 TimePix-based detector assembly, on the International Space Station (ISS) during the spring of 2012 as part of a Station Detailed Test Objective (SDTO). These...
We have developed a novel method for joint frequency and 2D angle estimation of incoming signals upon a circular array over a very wide frequency band (2–18 GHz)[1]. This paper presents the algorithm with diagonal load for robust performance with improved accuracy and resolution. A temporal domain ESPRIT frequency estimation algorithm was extended for azimuth and elevation angles estimation. These...
This paper discusses the modern approach of the implementation NASA Technology Transfer System as a Software as a Service (SaaS) for NASA as a way to reduce cost and increase efficiency. To accommodate scalability and flexibility, a private cloud called XML Datastore (XD) is used as the foundation to provide a SaaS framework. This is implemented to support three verticals, which consists of the NASA...
Currently, most microprocessors use multiple cores to increase performance while limiting power usage. Some processors use not just a few cores, but tens of cores or even 100 cores. One such many-core microprocessor is the Maestro processor, which is based on Tilera's TILE64 processor. The Maestro chip is a 49-core, general-purpose, radiation-hardened processor designed for space applications. The...
This paper presents the development of a high efficiency, rad-hard 3.8 kW silicon carbide (SiC) based power processing unit (PPU) power supply for the High Voltage Hall Accelerator (HiVHAC) Hall effect thruster. The power converter utilizes SiC JFET power switches which have on-resistance an order of magnitude smaller than equivalent 600V rad-hard silicon MOSFETs. A prototype PPU power converter was...
In this paper, an evaluation technique based on several image feature attributes along with image classifications is investigated. Furthermore, a semi-supervised technique based on support vector machine (SVM) for image classification and a Locality Sensitive Hashing (LSH) based searching algorithm to search for similarity of satellite imagery is presented. Given a query image, the goal is to retrieve...
Solar conjunctions pose many challenges to the planning and operation of the MESSENGER mission to Mercury. A solar conjunction occurs when the spacecraft and the Sun appear near to each other in the celestial sky relative to Earth-based antennas, within 3° of each other from the point of view of project planning. The conjunction can be a superior solar conjunction, during which the spacecraft is on...
Deep-space missions traditionally use sequential, turnaround ranging to measure the distance to the spacecraft. The spacecraft demodulates the uplinked ranging signal (composed of sequential frequency tones) and retransmits it (“turnaround”) onto the downlink. Since this operation is bent-pipe, noise on the uplink within the ranging channel bandwidth is also retransmitted. When the received uplink...
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