Air force 7. Small Business Innovation Research (sbir) Phase I proposal Submission Instructions

High DeltaV also makes it possible to leverage the increased availability and affordability of launches to Low Earth Orbit (LEO). A small satellite with sufficient DeltaV could share a relatively inexpensive ride to LEO and subsequently travel to GEO with enough DeltaV remaining to traverse the belt. The efficiency of electric thrusters comes at the expense of thrust. Conducting a low-thrust transfer from LEO to GEO will take several months. Accordingly, the satellite system must be sufficiently radiation hardened to endure a slow trip through the radiation belts.

PHASE I: Conduct system trades to identify an inspector satellite mission concept to provide better than 0.1m resolution imagery of several GEO satellites. Design the satellite with 6 km/s DeltaV capable of surviving a slow journey from LEO to GEO through the radiation belts. Identify appropriate sensor/telescope options, orbital configuration, and downlinks.

PHASE II: Based on the Phase I effort, provide system validation of the mission concept and satellite design. Complete satellite design through critical design review (CDR) and build a ground demonstration unit of the satellite to validate performance. Conduct a hardware-in-the-loop simulation of the system concept to validate system performance.  Model orbital dynamics, subsystem metric, sensor imaging, data downlink, and image processing for a timeline of tasking to tactical image product.

PHASE III DUAL USE APPLICATIONS: The contractor will pursue commercialization of the various technologies developed in Phase II for transitioning expanded mission capability to a broad range of potential government and civilian users and alternate mission applications.

REFERENCES:

1. James Szabo, Bruce Pote, Surjeet Paintal, Mike Robin, Adam Hillier, Richard D. Branam, and Richard E. Huffmann.  "Performance Evaluation of an Iodine-Vapor Hall Thruster", Journal of Propulsion and Power, Vol. 28, No. 4 (2012), pp. 848-857.

2. T. Haberkorn, P. Martinon, and J. Gergaud.  "Low Thrust Minimum-Fuel Orbital Transfer: A Homotopic Approach", Journal of Guidance, Control, and Dynamics, Vol. 27, No. 6 (2004), pp. 1046-1060.

3. William A. Hargus, and James T. Singleton.  "Application of Technology Readiness Levels to Micro-Propulsion Systems." 52nd AIAA/SAE/ASEE Joint Propulsion Conference (2016), paper AIAA-2016-5113.

KEYWORDS: small satellite, advanced propulsion, high specific impulse, orbital maneuver, space situational awareness.

AF171-075

TITLE: Assured Autonomous Spacecraft GN&C via Hybrid Control

TECHNOLOGY AREA(S): Space Platforms

OBJECTIVE: Develop innovative, novel approaches for hybrid mode-logic/discrete-time control/continuous-time physics spacecraft systems that provide mathematically rigorous guarantees of system behavior and performance.

DESCRIPTION: GN&C systems that involve mode-switching logic or gain-scheduling are both examples of a hybrid system, where the dynamics of a finite-state machine (e.g., the mode-logic or the gain-schedule) interact with the dynamics of a continuous-valued system (e.g., the attitude control system & attitude dynamics). State-of-practice for such systems involves rigorous analysis of both the continuous-valued system and the finite-state machine individually via standard techniques. But analysis of the coupled system comprised of the connected mode-logic and control systems is beyond current analysis approaches - regression testing via Monte-Carlo (MC) analysis is the only option, and does not provide rigorous guarantees. Recently, techniques have been published in the literature that allow rigorous analysis of these coupled system behaviors, and in some cases can design coupled mode-logic/control systems with rigorous guarantees for stability and robustness. This SBIR will apply these techniques to missions of AF interest and demonstrate the utility of the resulting set calculations. Techniques of interest include but are not limited to analysis approaches (e.g., linear-temporal logic specification verification via system approximation, bisimulation, model-checking) as well as synthesis approaches (e.g., guaranteed performance via composition or other proofs).

PHASE I: Perform literature survey of methods. Working with sponsor, identify appropriate application example(s) & metrics that methods will be evaluated against. Perform trade study to down-select to one or two algorithms that will form the basis of a Phase-II effort. Document results in a Final Report, and deliver any simulation software to the sponsor.

PHASE II: Develop selected algorithms into suitable software capable of producing results in practical time periods. Develop high-fidelity simulation of application of AF interest with sponsor. Integrate algorithms with simulation to demonstrate utility against metrics. Working with sponsor, examine opportunities for transition of technology to customers of interest.

PHASE III DUAL USE APPLICATIONS: Develop and apply algorithms to specific system of interest to sponsor. Work with sponsor, customer, and associated contractors to integrate algorithms and software into application of interest.

REFERENCES:

1. S. Karaman, R. Sanfelice, and E. Frazzoli, “Optimal control of mixed logical dynamical systems with linear temporal logic specifications,” in Decision and Control, 2008. CDC 2008. 47th IEEE Conference on, Dec 2008, pp. 2117–2122.

2. S. Di Cairano, W. Heemels, M. Lazar, and A. Bemporad, “Stabilizing dynamic controllers for hybrid systems: A hybrid control lyapunov function approach,” Automatic Control, IEEE Transactions on, vol. 59, no. 10, pp. 2629–2643, Oct 2014.

3. Tabuada, Paulo. Verification and control of hybrid systems: a symbolic approach. Springer Science & Business Media, 2009.

4. Duggirala, Parasara Sridhar, Mitra, Sayan, and Viswanathan, Mahesh, "C2E2: A Verification Tool For Stateflow Models," In Proceedings of 21st International Conference Tools and Algorithms for the Construction and Analysis of Systems (TACAS) 2015, London

5. Liu, Jun, et al. "Synthesis of reactive switching protocols from temporal logic specifications." Automatic Control, IEEE Transactions on 58.7 (2013): 1771-1785.

KEYWORDS: hybrid, cyber-physical, verification, validation, control, guidance, attitude, orbital

AF171-076

TITLE: Wideband GPS Digital Payload Architecture

TECHNOLOGY AREA(S): Space Platforms

The technology within this topic is restricted under the International Traffic in Arms Regulation (ITAR), 22 CFR Parts 120-130, which controls the export and import of defense-related material and services, including export of sensitive technical data, or the Export Administration Regulation (EAR), 15 CFR Parts 730-774, which controls dual use items. Offerors must disclose any proposed use of foreign nationals (FNs), their country(ies) of origin, the type of visa or work permit possessed, and the statement of work (SOW) tasks intended for accomplishment by the FN(s) in accordance with section 5.4.c.(8) of the solicitation and within the AF Component-specific instructions. Offerors are advised foreign nationals proposed to perform on this topic may be restricted due to the technical data under US Export Control Laws. Please direct questions to the AF SBIR/STTR Contracting Officer, Ms. Gail Nyikon, [e-mail].

OBJECTIVE: Develop a Global Positioning System (GPS) transmitter architecture capable of generating the L1, L2, and L5 signals and additional arbitrary signals at discretionary frequencies between 1 and 2 GHz.

DESCRIPTION: GPS broadcasts radio frequency ranging signals at three frequencies: L1 (1575.42 MHz), L2 (1227.6 MHz), and L5 (1176.45 MHz). Multiple signals are modulated onto each frequency, and the nominal bandwidth of each frequency channel is 30.69 MHz. Traditional GPS payloads are comprised of separate transmitters for each frequency, with the RF outputs of each transmitter combined in a multiplexer (triplexer in the case of L1, L2, and L5) and broadcast through a single L-Band antenna.

As digital techniques for RF signal generation have evolved, wideband Direct Digital Synthesis (DDS) supporting bandwidths of tens to hundreds of GHz has been developed for high capacity digital communications. Most of these applications, however, are used at much higher carrier frequencies where a multi-GHz bandwidth is a relatively small fraction of the carrier frequency.

For purposes of this topic, consider the GPS Band as the entire range of frequencies that encompasses GPS, from 1161 MHz to 1591 MHz (total bandwidth of 430 MHz). Within the GPS Band are three sub-bands: the L5 sub-band centered at 1176.45 MHz with 30.69 MHz bandwidth, the L2 sub-band centered at 1227.6 MHz with 30.69 MHz bandwidth, and the L1 sub-band centered at 1575.42 MHz with 30.69 MHz bandwidth.

To support experimental L-Band signals, the wideband architecture should also support generation of arbitrary direct sequence spread spectrum signals anywhere from 1 to 2 GHz. These arbitrary signals are for test purposes only, and can be assumed to be similar to GPS signals, although lower in power and with varying chipping rates and signal structure.

Develop a payload architecture to produce signals ranging from 1 to 2 GHz that includes the three GPS sub-bands, in accordance with GPS signal in space interface specifications. Special consideration should be given to complying with out of band emission requirements, which apply to emissions outside of each sub-band. The principle technical questions to be addressed are:
1. Does DDS of the entire GPS Band improve the overall efficiency of the GPS payload?
2. Are their suitable high-efficiency amplifiers that will provide low-distortion and high gain over the entire GPS Band? Would an alternative amplifier configuration be more suitable?
3. Can this approach produce high quality signals with low phase noise, acceptable group delay, and low distortion?
4. Can a Wideband GPS Transmitter Architecture support additional signals over the 1-2 GHz range?
The developer is encouraged to create and implement reference models of the new architecture(s) and the traditional architecture (with separate transmitters) to allow for direct comparison. The desired improvement is 50% reduction of total payload power consumption when delivering minimum signal power as specified in GPS signal in space interface specifications.

PHASE I: Develop an architecture and preliminary design for multi-carrier DDS of the GPS signals, to include waveform generation, filtering, amplification, and other associated hardware. No government materials, equipment, data, or facilities are required for this phase.

PHASE II: Produce breadboard or engineering design model demonstration(s) of multi-carrier DDS and test with L1, L2, and L5 GPS receivers. No government materials, equipment, data, or facilities are required for this phase.

PHASE III DUAL USE APPLICATIONS: Develop DDS payload(s) and implementations of reference PNT (position, navigation, and timing) system architectures, suitable for flight experiment assembly, integration, and test. Commercial: Application to GNSS satellites, GNSS augmentations, and pseudolites.

REFERENCES:

1. P. Eloranta, P. Seppinen and A. Parssinen, Direct-digital RF-modulator: a multi-function architecture for a system-independent radio transmitter, in IEEE Communications Magazine, vol. 46, no. 4, pp. 144-151, April 2008.

2. Antoine Diet, Fabien Robert, Genevieve Baudoin, Martine Villegas, Philippe Cathelin, et al., RF Transmitter Architectures for Nomadic Multi-radio: A Review of the Evolution Towards Fully Digital Solutions. Recent Patents on Electrical & Electronic Engineering, 2013, 6 (2), pp.79-94 (16).

3. Ortega-Gonzalez, F.J.; Tena-Ramos, D.; Patino-Gomez, M.; Pardo-Martin, J.M.; Madueno-Pulido, D., High-Power Wideband L-Band Suboptimum Class-E Power Amplifier, Microwave Theory and Techniques, IEEE Transactions on , vol.61, no.10, pp.3712,3720, Oct. 20

4. GPS Interface specifications: IS-GPS-200, ICD-GPS-700, IS-GPS-705, IS-GPS-800.

KEYWORDS: GPS, Direct Digital Synthesis, DDS, wideband transmitter, wideband amplifier

AF171-077

TITLE: Cyber Vulnerabilities & Mitigations in the Radio Frequency Domain

TECHNOLOGY AREA(S): Space Platforms

The technology within this topic is restricted under the International Traffic in Arms Regulation (ITAR), 22 CFR Parts 120-130, which controls the export and import of defense-related material and services, including export of sensitive technical data, or the Export Administration Regulation (EAR), 15 CFR Parts 730-774, which controls dual use items. Offerors must disclose any proposed use of foreign nationals (FNs), their country(ies) of origin, the type of visa or work permit possessed, and the statement of work (SOW) tasks intended for accomplishment by the FN(s) in accordance with section 5.4.c.(8) of the solicitation and within the AF Component-specific instructions. Offerors are advised foreign nationals proposed to perform on this topic may be restricted due to the technical data under US Export Control Laws. Please direct questions to the AF SBIR/STTR Contracting Officer, Ms. Gail Nyikon, [e-mail].

OBJECTIVE: Identify weaknesses and potential vulnerabilities of embedded system radios to cyber threats.

DESCRIPTION: The United States Department of Defense (DoD) continually designs, acquires, and deploys best in class, highly complex and capable embedded systems. Due to their often high cost, low-density, long development time lines, and the mission criticality of the services they may provide, DoD embedded systems have a high value to defense of DoD systems. As we have embraced enhanced embedded system computing capabilities, in most aspects we have become increasingly vulnerable to multiple types of cyber threats.

While vast resources have been invested with the goal of preventing or identifying intrusions and anomalous behavior within our networked enterprise architectures, comparatively little has been done to enhance the mission assurance properties of United States’ real-time, embedded computing systems, if they were to operate in increasingly cyber-contested environments. These systems are subject to customized attack types which target the custom hardware, software and firmware that is frequently found in these systems. State of the art approaches to cybersecurity typically focus only on securing components and end-nodes on the network rather than mission assurance and architectural resilience. When coupled with fundamentally flawed protection schemes common in cyber systems today, this approach creates an ecosystem ripe for potential exploitation. Mission assurance requires levels of prioritization where capabilities become the focus rather than the enabling systems. Furthermore, under stress or duress a resilient architecture will maintain some set of functionality, albeit restricted, to stay in mission and meet some level of mission requirements.

For many real-time, embedded systems used by the DoD, the primary method of communicating information is the radio frequency link and, as such, constitutes a lucrative and exposed cyber and electronic attack surface across the system’s operational life. Major subsystems of the platform, including radios and computers, may exhibit architectural, specification, and implementation vulnerabilities to a variety of RF-enabled cyber methods.
The focus of this topic is to develop a library of weaknesses and potential vulnerabilities that might be exploited by adversaries against a variety of radios within the context of real-time, embedded systems.

PHASE I: Perform research and development for the examination of RF-enabled cyber susceptibilities of real-time, embedded system radios, using a Government-furnished commercially-available off-the-shelf (COTS) radio as a case study.

Identify a library of weaknesses and potential vulnerabilities.
Formulate novel approaches for mitigation, and document in a final report.

PHASE II: On the basis of the Phase I research, conduct in-depth RF-enabled cyber vulnerability assessments on two Government-furnished real-time, embedded system radios.

Validate selected and prioritized weaknesses on the provided hardware.
As a capstone effort, implement innovative techniques for mitigation.

PHASE III DUAL USE APPLICATIONS: Use the library developed in Phases I and II to conduct a cyber vulnerability evaluation against an assigned embedded system.

Provide tool set engineering support to a cyber assessment against an assigned embedded system.
Investigate the usefulness of the developed tool for the assessment of existing or in-development commercial systems.

REFERENCES:

1. MacDonald, Douglas G. et al. “CYBER/PHYSICAL SECURITY VULNERABILITY ASSESSMENT INTEGRATION.” United States: INMM, Deerfield, IL, United States (US)., 2011. Print.

2. The Science of Mission Assurance. Jabbour, Kamal and Muccio, Sarah. 5, 2011, Journal of Strategic Security, Vol. 4, pp. 61-74.

KEYWORDS: cyber vulnerability assessment, RF-enabled cyber, embedded system cyber security, real-time system cyber security, cyber resiliency

AF171-078

TITLE: SWIR-LWIR detectors employing Unipolar Barrier Architectures

TECHNOLOGY AREA(S): Battlespace, Electronics, Sensors

OBJECTIVE: Experimentally quantify the fundamental performance limits of unipolar barrier architecture infrared detectors through design & fabrication of such devices, and address the question of whether bandgap engineered devices can actually outperform traditional photodetector designs.

DESCRIPTION: There are numerous scenarios where it is necessary to detect optical signals in either the Mid-Wave Infrared (MWIR: 3 – 6 microns) or Long-Wave IR (LWIR: 7 – 12 microns) spectral bands. Currently, mercury cadmium telluride (MCT) is the DoD workhorse that covers these spectral bands due to its high performance, which results from Fresnel-limited internal quantum efficiency and near diffusion-limited dark currents. The option for a heterojunction architecture in MCT results in dark currents that are even lower. The quantum efficiency may be taken to be roughly 65% without an anti-reflection coating, while the dark current is conventionally measured by “Rule 07”, as described in the references. These two metrics will effectively be used as the “signal” and “noise” baselines, against which design solutions will be evaluated.

Detector designs utilizing barriers have been experimentally shown to result in lower dark current than their non-barrier counterparts. Other performance advantages that apply equally well to bulk MCT detectors are of less interest. Thus, high levels of detector performance should be achieved solely by architecture design and should not be restricted to a particular material system, carrier type, barrier number, etc. This SBIR also emphasizes detectors that are optimized for only one spectral band, either MWIR or LWIR, at 80 Kelvin operating temperature; since both these wavelength regions have application for military space-based sensing. Designs employing multiple unipolar barriers, called complementary barrier devices, or multi-height barriers, called compound barrier devices, or any combination thereof, are all relevant to this SBIR. For example, strained-layer superlattice architectures that achieve lower than bulk levels of dark current might be particularly attractive.

PHASE I: The optimum unipolar barrier detector architecture for detecting in the MWIR or LWIR spectrum shall be designed. The detectors will be grown, processed, and, characterized. This shall include at a minimum absorption spectrum, dark current, optical responsivity, and quantum efficiency measurements. The detector will be mounted to a 68 pin leadless chip carrier and provided to AFRL/RVSW for independent characterization of the device. In addition, samples for carrier lifetime measurements should be provided to AFRL/RVSW for independent characterization.

PHASE II: During this phase, the barrier architecture detector will be grown such that it can be processed into a 1024x1024, 18µm pitch detector arrays that will be hybridized to government furnished Read Out Integrated Circuits (ROIC). The functionality of the Focal Plane Array (FPA) shall be demonstrated and thoroughly characterized at light levels reflective of strategic applications. Three (3) working FPA deliverables shall be provided to AFRL for independent radiometric characterization.

PHASE III DUAL USE APPLICATIONS: Commercialization prospects include civil (remote sensing, night vision, intrusion detection) and military (advanced space-based imaging for improved ISR and battlefield awareness) capabilities.

REFERENCES:

1. W.E. Tennant, D. Lee, M. Zandian, E. Piquette, and M. Carmody, “Rule ’07,’ Journal of Electronic Materials 37 (9), 1406 (2008).

2. S. Maimon and G. W. Wicks, Appl. Phys. Lett 89 (15), 151109 (2006).

3. W.E. Tennant, “Rule 07 Revisited: Still a Good Heuristic Predictor of p /n HgCdTe Photodiode Performance?” Journal of Electronic Materials Volume 39, Issue 7, pp 1030-1035, (2010).

4. V.M. Cowan, C.P. Morath, J.E. Hubbs, S. Myers, E. Plis, S Krishna, “Radiation tolerance characterization of dual band InAs/GaSb type-II strain-layer superlattice pBp detectors using 63 MeV protons”, Appl. Phys. Lett 101 251108 (2012).

5. C.P. Morath, V.M. Cowan, L.A. Treider, G.D. Jenkins, J.E. Hubbs, “Proton irradiation effects on the performance of III-V based, unipolar barrier infrared detectors” IEEE Trans. Nuclear Science Volume 62 Issue 2 (2016).

KEYWORDS: Strained-layer superlattice, mercury cadmium telluride, MCT, barrier architecture, sensors, focal plane array, nBn, pBiBn, pBp, space technologies

AF171-079

TITLE: Automatic Exploitation of Energetic Charged Particle Sensor Data

TECHNOLOGY AREA(S): Space Platforms

OBJECTIVE: Automate correlation of incidents of off-nominal spacecraft performance with energetic charged particle drivers to improve space environment anomaly attribution.

DESCRIPTION: New Air Force policy requires Energetic Charged Particle (ECP) sensors on all future spacecraft to enable differentiation between anomalies induced by hostile activity, the natural environment, or other non-hostile causes. It is presently possible to understand the generic space environment hazard to a spacecraft [1], but spacecraft susceptibilities are unique to each design and even to individual spacecraft due to minor variations, workmanship, and on-orbit wear and tear. As local ECP sensors proliferate, the ability to accurately specify the local space particle environment will improve, allowing a more detailed characterization of individual spacecraft susceptibilities to the natural environment. Identifying susceptibilities is presently labor-intensive, requiring a deep understanding of the limitations of the space particle sensors as well as the likely manifestations of anomalies due to environmental drivers. The application of modern data science techniques to the correlation of space environment data from on-board sources with instances of off-nominal behavior will be key to maximizing the utility of ECP sensors in an affordable manner.