Release Date
November 29th, 2023
Open Date
January 3rd, 2024
Due Date(s)
February 21st, 2024
Close Date
February 21st, 2024
Topic No.


Alternative Position, Navigation, and Timing


Department of DefenseN/A


Type: SBIRPhase: BOTHYear: 2024


The Department of Defense (DOD) is seeking proposals for the topic of "Alternative Position, Navigation, and Timing" as part of the SBIR 24.1 BAA. The objective of this solicitation is to provide resilient, multi-source, continuous, high-quality navigation and timing information for military, civil, and commercial users. The technology being sought should serve as an alternative or augmentation to GPS in situations where GPS signals are denied or degraded. The scope of this effort includes the provision of Alt-PNT services, hardware, software, and associated enabling technologies and approaches. Proposals may include Alt-PNT technologies and implementations needed within the domains of Alt-PNT Control systems, Space Segments, and User Equipment. The solicitation is closed, and the project duration and funding specifics are not provided in the document. For more information, refer to the solicitation agency website.




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 the Announcement. Offerors are advised foreign nationals proposed to perform on this topic may be restricted due to the technical data under US Export Control Laws.


OBJECTIVE: To provide resilient, multi-source, continuous, high quality, navigation and timing information by providing alternative, GPS-independent, navigation augmentation sources of positioning, navigation, and timing (PNT) data for the warfighter, civil and commercial user. Alt-PNT can augment GPS or serve as a short/medium-term alternative to GPS if access to GPS signals is denied or degraded.


DESCRIPTION: Military/Civil/Commercial users require resilient, integrated, high-precision PNT information in contested environments for vehicle autonomy and other emerging fields. This Alt-PNT effort seeks to leverage both government and commercial investments to develop and demonstrate technology to provide resilient navigation and timing information, either from novel sources or by integrating PNT information from existing sources in novel ways to enhance resilience. The scope of this effort includes provision of Alt-PNT services, hardware, software, and associated enabling technologies and approaches. This solicitation seeks proposals at the level of: Systems-of-Systems, System, Critical Item, and/or Device, which lead to Alt-PNT capability. Proposals may include Alt-PNT technologies and implementations needed within the domains of Alt-PNT Control systems, Space Segments, and User Equipment.


There are many Alt-PNT implementations that can provide PNT information independent of GPS, including (but not limited to): non-GPS space-based RF systems including global navigation satellite systems (GNSS), self-contained inertial navigation systems (INS), celestial navigation, computer vision-based approaches, network-based timing approaches, PNT-over-communications, signals of opportunity, and other land-based RF augmentation systems.


Several recent commercial efforts provide opportunities to increase PNT resilience through Alt-PNT. Those developments include: low cost proliferated LEO (pLEO) communication mega-constellations, low cost reusable launch vehicles, machine learning and artificial intelligence, quantum sensing, low cost high data-rate space laser crosslink networks, chip scale atomic clocks, very high density reconfigurable field programmable gate arrays, Graphical Processing Units, as well as the convergence of satellite communications and 5G/6G cell networks. These developments provide an overarching technological opportunity to enable all new alternative navigation services, completely independent of existing MEO GNSS systems.


Alt-PNT enablers are also of interest, including: low-cost, zero-trust, long-range, space-space networks, GNSS Situational Awareness, Integrity/Authentication Monitors, provision of GNSS Hot-Start data, global timing synchronization, and resilient C2 capability for PNT systems. These enabling capabilities address how Alt-PNT systems can be integrated with future heterogenous, multi-tier, highly integrated space assets to provide the resilient PNT.


PHASE I: As this is a Direct-to-Phase-II (D2P2) topic, no Phase I awards will be made as a result of this topic. To qualify for this D2P2 topic, the Government expects the Offeror to demonstrate feasibility by means of a prior “Phase I-type” effort that does not constitute work undertaken as part of a prior SBIR/STTR funding agreement.


This feasibility demonstration should encompass the evaluation of scientific and technical merit and feasibility of ideas with commercial potential. Additionally, it must validate the product-market between the proposed solution and the USSF customer. The feasibility study should identify the prime potential USSF end users for the Defense-modified commercial offering, describe integration feasibility and costs with current mission-specific products, and explore the potential use by other DoD or Governmental customers. Offeror Documentation should include all relevant information including, but not limited to: technical reports, test data, prototype designs/models, and performance goals/results. Prior work to demonstrate feasibility must meet the minimum technical and scientific merit specified in this description.

Work submitted with the feasibility demonstration must have been substantially performed by the Offeror and/or the Principal Investigator.


PHASE II: The emphasis will shift from study/analysis and technology development/selection towards end-to-end capability demonstration. Alt-PNT Phase-II proposals addressing System-of-System, System, and integration of Critical Items will be accepted, with priority placed on proposals that provide the most technically achievable, integrated MGNSS + Alt-PNT, end-to-end, user solutions.


Successful Phase-II proposals and awards will provide an end-to-end capability demonstration in a relevant laboratory operational environment, including initial field testing to prove that the proposed Alt-PNT capability is prepared to move in to limited production and limited operational field testing. The successful Phase-II Alt-PNT capability shall achieve TRL-5 (Threshold) or TRL-6 (Objective), as documented in a final report with laboratory and field demonstration.


PHASE III DUAL USE APPLICATIONS: "Finally, during Fiscal Year 2026 (Threshold) or earlier (Objective), a Phase-III down-select will occur to the most viable Alt-PNT candidates.  Technology development should be complete, teaming arraignments should be complete, production details should be complete. All outstanding cyber, integration, and operational details will have been resolved.  During Phase-III limited low rate production of sufficient sub-systems will be conducted to enable limited operational demonstration in the actual operational environments. All aspects of Alt-PNT control, space segment, user equipment, integration and operation needed for successful demonstration will be conducted. The successful Phase-III Alt-PNT capability shall achieve TRL-6 (Threshold) or TRL-7 (Objective) as documented in a final report with limited production and operational demonstration.

The Alt-PNT capability sought to be developed under this program will directly benefit the warfighter, civil user, and potentially create a new class of pay-for-use commercial PNT user."



"PNT Advisory Board (PNTAB)
 Protect, Toughen, Augment (PTA)
DoD Technology Readiness Level Definitions:
 Stanford GPS Laboratory. 
 Reid, T. G. R.,Neish, A. M. Walter, T., and Enge, P. K. “Broadband LEO Constellations for Navigation,” J Inst Navig, 65: 205–220.
 F. Menzione and M. Paonni, ""LEO-PNT Mega-Constellations: a New Design Driver for the Next Generation MEO GNSS Space Service Volume and Spaceborne Receivers,"" 2023 IEEE/ION Position, Location and Navigation Symposium (PLANS), Monterey, CA, USA, 2023, pp. 1196-1207, doi: 10.1109/PLANS53410.2023.10140052.
 F. Rothmaier, Y. -H. Chen, S. Lo and T. Walter, ""A Framework for GNSS Spoofing Detection Through Combinations of Metrics,"" IEEE Transactions on Aerospace and Electronic Systems, vol. 57, no. 6, pp. 3633-3647, Dec. 2021, doi: 10.1109/TAES.2021.3082673.
 Neish A, Walter T, EngeP. “Quantum‐resistant authentication algorithms for satellite‐based augmentation systems,” NAVIGATION. 2019;
 Babcock-Chi, Jade, Trapani, Lucca, Akos, Dennis, ""Timekeeping with a Chip Scale Atomic Clock in GPS Denied Environments,"" Proceedings of the 2023 International Technical Meeting of The Institute of Navigation, Long Beach, California, January 2023, pp. 34-52.


KEYWORDS: Alt-PNT; hybrid user equipment; blended PNT solutions; PNT situational awareness; commercial PNT services; prototypes; hosted payloads; hosting payloads; resilient PNT; GPS resilience; "PNT as a service"; commercial PNT; alternate timing distribution; Open Systems Architecture; GPS; GNSS; Anti-Jam; Anti-Spoof; Complementary PNT; Alternate PNT; inertial; celestial; magnetic; gravimeteric; terrain mapping; Signals of Opportunity; LEO; MEO; GEO; signal processing; antennas;  signals; compact atomic clocks; Situational Awareness; M-Code; atomic clocks; machine vision; constellation; cislunar; agile; NAVWAR; absolute nav; relative nav; scalable; multi-tier MGNSS;  secure processing; assured PNT; quantum sensing; MGNSS User Equipment; Software Defined MGNSS; certifiable software define radios; comm-PNT convergence; zero trust; post-quantum; authentication; cryptography; key management; ML; AI;