This PDF file contains the front matter associated with SPIE Proceedings Volume 10196, including the Title Page, Copyright information, Table of Contents, Introduction (if any), and Conference Committee listing.

One of the main problems faced by the Space Situational Awareness community is the detection and characterization of faint objects around geosats. Independent of the origin of these objects, whether they are debris or controlled spacecraft, they can potentially harm these assets and contaminate the geobelt environment. The challenge of detecting these companion objects comes from their proximity and brightness ratio relative to geosats. Here we present a novel interferometric fringe nulling technique, aimed at solving these issues. This technique takes advantage of the fact that the presence of companions introduces large phase fluctuations in the fringe phase observed by an interferometer, when the interferometer is observing a target at spatial frequencies where the fringe amplitude is near zero. We describe the ongoing development of this technique at the Navy Precision Optical Interferometer, and the results of simulations of interferometric observations of satellites with companions. We also present the current state of the NPOI and related SSA work being done with this interferometer, as well as undergoing upgrades to the system.

The effects of irradiations on MOSFET and bipolar junction transistors are well known though irradiation mechanisms in two-dimensional graphene and related devices are still being investigated. In this work, we investigate irradiation mechanism based on a semi-empirical model for the graphene back-gate transistor and quantitatively analyze the irradiation influences on electrical properties of the device structure. The irradiation shifts the current which changes the region of device operation, degrades the mobility and increases the channel resistance which can increase the power dissipation. The main mechanism causing the degradation in performance of devices is the oxide trap charges near the SiO₂/graphene interface and graphene layer traps charges.

UV(ultraviolet) image intensifier is a vacuum image device with Cs2Te (Cesium Tellurium) photocathode. It converts the incident ultraviolet(UV) light from the optical lens into electronic signal, then the electronic signal is converted into responding visible image on the phosphor screen. Defects of different sizes can be seen on the screen when it works. A system is build to inspect the distribution of the defects, then the sources and category of the defects of the view field are analyzed, including photocathode, microchannel plate and phosphor screen, some improving technique is brought to decrease the defects.

With the rapid development of space exploration and utilization, orbital debris increases dramatically, leading to great threat to human space activities and spacecraft security. In this paper, a new type of multi-functional space debris satellite system (MSDS) was put forward, which shared main optical system, and possessed functions of multidimensional information detection, polarized remote sensing and high rate transmission. The MSDS system can meet the requirements of detection and identification for the small orbital debris which is 1000km faraway, as well as the requirements of the data transmission by 50 Mbps to 2.5 Gbps@200-1000 km. At the same time, by the method of satellite orbital maneuver and attitude adjusting, the orbital debris information that is real-time, complex and refined, allweather can be acquired and transmitted by the new system. Such new type of multifunctional satellite system can provide important and effective technology for international orbital debris detection.

The space environment is considered hazardous to spacecraft, resulting in materials degradation. Understanding the degradation of space-based instruments is crucial in order to achieve the scientific objectives, which are derived from these instruments. This paper discusses the on-orbit performance degradation of recent spacebased solar instruments. We will focus on the instruments of three space-based missions such as the Project for On-Board Autonomy 2 (PROBA2) spacecraft, the Solar Monitoring Observatory (SOLAR) payload onboard the Columbus science Laboratory of the International Space Station (ISS) and the PICARD spacecraft. Finally, this paper intends to understand the degradation processes of these space-based solar instruments.

Recent advances in big data (BD) have focused research on the volume, velocity, veracity, and variety of data. These developments enable new opportunities in information management, visualization, machine learning, and information fusion that have potential implications for space situational awareness (SSA). In this paper, we explore some of these BD trends as applicable for SSA towards enhancing the space operating picture. The BD developments could increase in measures of performance and measures of effectiveness for future management of the space environment. The global SSA influences include resident space object (RSO) tracking and characterization, cyber protection, remote sensing, and information management. The local satellite awareness can benefit from space weather, health monitoring, and spectrum management for situation space understanding. One area in big data of importance to SSA is value - getting the correct data/information at the right time, which corresponds to SSA visualization for the operator. A SSA big data example is presented supporting disaster relief for space situation awareness, assessment, and understanding.

The U.S. Air Force (USAF) has recognized the needs for owning the program and technical knowledge within the Air Force concerning the systems being acquired to ensure success. This paper extends the previous work done by the authors [1-2] on the “Resilient Program Technical Baseline Framework for Future Space Systems” and "Portfolio Decision Support Tool (PDST)” to the development and implementation of the Program and Technical Baseline (PTB) Tracking Tool (PTBTL) for the DOD acquisition life cycle. The paper describes the “simplified” PTB tracking model with a focus on the preaward phases and discusses how to implement this model in PDST.

The paper describes the MATLAB (MathWorks) programs that were developed during the REU workshop¹ to implement The Aerospace Corporation developed Unified Game-based Acquisition Framework and Advanced Game - based Mathematical Framework (UGAF-AGMF) and its associated War-Gaming Engine (WGE) models. Each game can be played from the perspectives of the Department of Defense Acquisition Authority (DAA) or of an individual contractor (KTR). The programs also implement Aerospace’s optimum “Program and Technical Baseline (PTB) and associated acquisition” strategy that combines low Total Ownership Cost (TOC) with innovative designs while still meeting warfighter needs. The paper also describes the Bayesian Acquisition War-Gaming approach using Monte Carlo simulations, a numerical analysis technique to account for uncertainty in decision making, which simulate the PTB development and acquisition processes and will detail the procedure of the implementation and the interactions between the games.

This paper describes static Bayesian game models with “Pure” and “Mixed” games for the development of an optimum Program and Technical Baseline (PTB) solution for affordable acquisition of future space systems. The paper discusses System Engineering (SE) frameworks and analytical and simulation modeling approaches for developing the optimum PTB solutions from both the government and contractor perspectives.

This paper describes cooperative and non-cooperative static Bayesian game models with complete and incomplete information for the development of optimum acquisition strategies associated with the Program and Technical Baseline (PTB) solutions obtained from Part 1 of this paper [1]. The optimum acquisition strategies discussed focus on achieving “Affordability” by incorporating contractors’ bidding strategies into the government acquisition strategies for acquiring future space systems. The paper discusses System Engineering (SE) frameworks, analytical and simulation approaches and modeling for developing the optimum acquisition strategies from both the government and contractor perspectives for Firm Fixed Price (FFP) and Fixed Price Incentive Firm (FPIF) contract types.

For the short-arc angle only orbit initialization problem, the admissible area is often used. However, the accuracy using a single sensor is often limited. For high value space objects, it is desired to achieve more accurate results. Fortunately, multiple sensors, which are dedicated to space situational awareness, are available. The work in this paper uses multiple sensors’ information to cooperatively initialize the orbit based on the fusion of multiple admissible areas. Both the centralized fusion and decentralized fusion are discussed. Simulation results verify the expectation that the orbit initialization accuracy is improved by using information from multiple sensors.

This paper develops and evaluates an orbital emulator (OE) for space situational awareness (SSA). The OE can produce 3D satellite movements using capabilities generated from omni-wheeled robot and robotic arm motion methods. The 3D motion of a satellite is partitioned into the movements in the equatorial plane and the up-down motions in the vertical plane. The 3D actions are emulated by omni-wheeled robot models while the up-down motions are performed by a stepped-motor-controlled-ball along a rod (robotic arm), which is attached to the robot. For multiple satellites, a fast map-merging algorithm is integrated into the robot operating system (ROS) and simultaneous localization and mapping (SLAM) routines to locate the multiple robots in the scene. The OE is used to demonstrate a pursuit-evasion (PE) game theoretic sensor management algorithm, which models conflicts between a space-based-visible (SBV) satellite (as pursuer) and a geosynchronous (GEO) satellite (as evader). The cost function of the PE game is based on the informational entropy of the SBV-tracking-GEO scenario. GEO can maneuver using a continuous and low thruster. The hard-in-loop space emulator visually illustrates the SSA problem solution based PE game.

Typical surveillance systems employ decision- or feature-level fusion approaches to integrate heterogeneous sensor data, which are sub-optimal and incur information loss. In this paper, we investigate data-level heterogeneous sensor fusion. Since the sensors monitor the common targets of interest, whose states can be determined by only a few parameters, it is reasonable to assume that the measurement domain has a low intrinsic dimensionality. For heterogeneous sensor data, we develop a joint-sparse data-level fusion (JSDLF) approach based on the emerging joint sparse signal recovery techniques by discretizing the target state space. This approach is applied to fuse signals from multiple distributed radio frequency (RF) signal sensors and a video camera for joint target detection and state estimation. The JSDLF approach is data-driven and requires minimum prior information, since there is no need to know the time-varying RF signal amplitudes, or the image intensity of the targets. It can handle non-linearity in the sensor data due to state space discretization and the use of frequency/pixel selection matrices. Furthermore, for a multi-target case with J targets, the JSDLF approach only requires discretization in a single-target state space, instead of discretization in a J-target state space, as in the case of the generalized likelihood ratio test (GLRT) or the maximum likelihood estimator (MLE). Numerical examples are provided to demonstrate that the proposed JSDLF approach achieves excellent performance with near real-time accurate target position and velocity estimates.

Software defined radio (SDR) has become a popular tool for the implementation and testing for communications performance. The advantage of the SDR approach includes: a re-configurable design, adaptive response to changing conditions, efficient development, and highly versatile implementation. In order to understand the benefits of SDR, the space telecommunication radio system (STRS) was proposed by NASA Glenn research center (GRC) along with the standard application program interface (API) structure. Each component of the system uses a well-defined API to communicate with other components. The benefit of standard API is to relax the platform limitation of each component for addition options. For example, the waveform generating process can support a field programmable gate array (FPGA), personal computer (PC), or an embedded system. As long as the API defines the requirements, the generated waveform selection will work with the complete system. In this paper, we demonstrate the design and development of adaptive SDR following the STRS and standard API protocol. We introduce step by step the SDR testbed system including the controlling graphic user interface (GUI), database, GNU radio hardware control, and universal software radio peripheral (USRP) tranceiving front end. In addition, a performance evaluation in shown on the effectiveness of the SDR approach for space telecommunication.

In this paper, a Cognitive Radio Network (CRN) based on artificial intelligence is proposed to distribute the limited radio spectrum resources more efficiently. The CRN framework can analyze the time-sensitive signal data close to the signal source using fog computing with different types of machine learning techniques. Depending on the computational capabilities of the fog nodes, different features and machine learning techniques are chosen to optimize spectrum allocation. Also, the computing nodes send the periodic signal summary which is much smaller than the original signal to the cloud so that the overall system spectrum source allocation strategies are dynamically updated. Applying fog computing, the system is more adaptive to the local environment and robust to spectrum changes. As most of the signal data is processed at the fog level, it further strengthens the system security by reducing the communication burden of the communications network.

The OpenOrbiter I spacecraft is the culmination of significant work on reducing the cost levels of a CubeSat-class spacecraft. By redesigning the spacecraft from the ground up, down to the component level, to use readily available electronic and physical components, the cost of CubeSat construction has been significantly reduced. This paper provides an overview of the OpenOrbiter I mission, to date. It then focuses on the benefits that can be provided by the lower-cost, low-risk spacecraft. The paper discusses the prospective utility of this mission paradigm for the defense, homeland security and intelligence communities.

Three-dimensional printing (also known as additive manufacturing) in space is a practical solution to reducing the mass and volume required for bringing materials into orbit and beyond. Materials can be launched in their raw form and transformed into the requisite parts and structures, as needed. This provides flexibility, allows structures to be designed to only support microgravity and allows sensing systems to be configured (and reconfigured) based on needs identified during the mission. This paper presents work undertaken to identify materials that are well-suited to in-space 3D printing. Materials commonly used for aerospace hardware were examined to assess their suitability.

Efficient power generation is crucial to the design of spacecraft. Mass, volume, and other limitations prevent the use of traditional spacecraft support structures from being suitable for the size of solar array required for some missions. Folding solar panel / panel array systems, however, present a number of design challenges. This paper considers the electrical design of an origami system. Specifically, it considers how to provide low impedance, durable channels for the generated power and the electrical aspects of the deployment system and procedure. The ability to dynamically reconfigure the electrical configuration of the solar cells is also discussed. Finally, a small satellite test mission to demonstrate the technology is proposed, before concluding.

This paper presents a discussion of techniques for low-cost design and construction of a CubeSat mechanical structure that can serve as a basis for academic programs and a starting point for government, military and commercial large-scale sensing networks, where the cost of each node must be minimized to facilitate system affordability and lower the cost and associated risk of losing any node. Spacecraft Design plays a large role in manufacturability. An intentionally simplified mechanical design is presented which reduces machining costs, as compared to more intricate designs that were considered. Several fabrication approaches are evaluated relative to the low-cost goal.

This paper considers the mechanical design of a low-mass, low-cost spacecraft for use in a multi-satellite sensing constellation. For a multi-spacecraft mission, aggregated small mass and cost reductions can have significant impact. One approach to mass reduction is to make cuts into the structure, removing material. Stress analysis is used to determine the level of material reduction possible. Focus areas for this paper include determining areas to make cuts to ensure that a strong shape remains, while considering the comparative cost and skill level of each type of cut. Real-world results for a CubeSat and universally applicable analysis are presented.