Expeditionary Very Low Frequency (ExVLF) Transmitter System

Area of Interest (AOI): Expeditionary Very Low Frequency (ExVLF) Transmitter SystemPAO Release Number: NAVWAR HQCA-2026-A-071Notice to Industry: This is an AOI issued under Naval Information Warfare Systems Command (NAVWAR) Commercial Solutions Opening (CSO) number N0003925S0001. This AOI solicits white papers/solution briefs (Phase 1 of the CSO) from industry. To the extent that any implementing regulations have not been updated to reflect statutory changes, the terms of the statute shall govern. Responses Due: 13-AUG-2026 at 2:00 PM PDTQuestions Due: 28-JUL-2026 at 2:00 PM PDTThe Government may not address all questions received. Questions and Answers will be posted on the NAVWAR CSO Website: https://www.navwar.navy.mil/Work-With-Us/Open-CSO-Calls/.Contact information for questions and technical/submission issues: ian.m.robinson14.civ@us.navy.milBackground:The Expeditionary Very Low Frequency (ExVLF) communications system is a modular, relocatable communications suite supported by an aerostat-lofted tethered antenna that enables 24/7 VLF radio wave data broadcasts over distance to maritime mobile and shore-based receive nodes.Problem StatementThe US Navy seeks solutions for an Expeditionary Very Low Frequency (ExVLF) transmitter system. The Navy requires a high-reliability solution that supports 24-hour per day, 7-day per week (24/7) data broadcast operations. As a result of this AOI, it is anticipated that initial efforts will focus on a prototype delivery phase, with potential options for follow-on production units to satisfy long-term operational inventory objectives. The system must be designed for deployment in rugged, multi-environment locations and integrate with Government-Furnished Equipment (GFE).Primary Solution Attributes:? High-Power Performance and Tuning: A containerized VLF transmitter system, consisting of a power amplification subsystem and a dynamic and automatic tuning element subsystem, designed to generate and radiate RF power by integrating with and automatically tuning to the specific complex impedance characteristics of a government-furnished Wireless Communications Aerostat (WCA) tethered antenna.? Integrated Transmitter System: The entire transmitter system must be housed within a no greater than 20-foot ISO general-purpose freight container to ensure it is transportable, deployable, and relocatable in diverse environments. The assembly must be hardened for deployment in rugged environments and include all necessary subsystems for operation.? Modulator and Signal Generation: An integrated subsystem to generate the required VLF waveforms. All signal characteristics, including modulation formats, reference frequency accuracy, and timing, must be sufficient to meet the top-level requirements of the ExVLF data broadcast mission.? Control and Monitoring System: A unified control system for local and remote operation of the transmitter. It should provide status monitoring, fault detection, and the ability to interface with the overarching ExVLF network command and control structure.? Mast and Feedline System: A deployable mast and feedline to provide the RF connection from the transmitter to the WCA mooring station.? Ground Plane System: A deployable ground plane system to ensure efficient RF radiation from the antenna system.? Interoperability: The system must be made interoperable with GFE, including a prepared flight pad, the WCA system, communications equipment, site logistics vehicles, and site power.Desired Solution Attributes:? Mobile Power Delivery System (MPDS): The MPDS provides the necessary operational power to the WCA (excluding transmission RF power). The Government seeks a full spectrum of solutions, both with and without an integrated MPDS. Additionally, we welcome proposals for a separately priced MPDS option. The MPDS shall provide power based on the aerostat vendors requirements; it shall function with or without RF power being transmitted; it shall fit within the primary transmitter equipment International Organization for Standardization (ISO) container; and it shall draw its prime power from the primary transmitter power distribution unit (PDU) or an external PDU. ? Next-Generation Transmitter Technology: Implement modern, efficient, and agile transmitter designs that offer greater efficiency, reliability, flexibility, or ease of control than legacy transmitters.? Smarter Station Control and Automation: Artificial Intelligence and machine learning for predictive maintenance, automatic tuning, or dynamic adjustments based on environmental conditions.? Hardening and Resiliency: While the VLF transmitter must be resilient to natural events (e.g., lightning, severe thunderstorms, and earthquakes), new materials, technologies and methodologies could enhance robustness, prevent system damage, and reduce the impact on transmitter operations by enabling it to continue broadcasting throughout an event. Measures must also be taken to guard against manmade events (such as cyberattacks or operator error) through hardening and other protective features. ? Enhanced Maintainability: Modern maintenance tools such as AI/ML based predictive maintenance, Built-In Test (BIT), self-healing software, autonomous component failover, and hot-swap components can dramatically reduce the maintenance burden on system maintainers, minimize site downtime, and optimize utilization of spare parts. Steps should be taken to reduce the maintenance burden on transmitter maintainers.? Technical Data and Supportability: Successful long-term sustainment necessitates availability and access to detailed system technical manuals, drawings and parts lists, training, technical support, and spare parts for the life of the system. Transmitter sustainment and supportability should be considered. Immersive training tools such as augmented reality and digital twins can be used to enhance the training experience operators and maintainers receive, enhancing their ability to sustain the system. Additional Notes:? Cybersecurity: Cybersecurity and Information Assurance best practices must be implemented and strictly adhered to. Measures must also be taken to protect the supply chain from malicious and/or counterfeit software and hardware components to ensure safe, secure, and reliable operation of the system.? Security: Companies must have experience deploying on classified networks and ability to perform work in these environments and cleared personnel who can work up to TS/SCI. It is encouraged that submissions highlight experience with controlled environments, such as deployments in classified data/environments (https://public.cyber.mil/dccs/). Preference will be given to companies whose solutions can be deployed to meet DoD security standards, or have an equivalent Authority to Operate (ATO). ? Demonstration: Companies are expected to describe how their solution will meet Government requirements via a presentation in an unclassified environment as part of Phase 2 of the CSO AOI. o Technical Viability: Explaining exactly how your commercial technology solves the governments specific mission problem.o Rough Order of Magnitude (ROM): Providing a high-level, preliminary cost estimate and commercial pricing model.o Project Schedule: Presenting a notional timeline and key milestones for the prototyping phase.o Data Rights and IP: Asserting your companys positions on intellectual property, data rights, and software licensing.o Live QandA / Demonstration: Evaluators will ask questions to your technical team on potential bottlenecks.? Teaming: The Government may seek to team companies with complementary solutions under the umbrella of this AOI; or in coupling of other AOIs issued within NAVWAR. Selected vendors may be requested to engage in partnerships with other vendors to achieve Government objectives.? Prototype Projects: The Government is interested in mature commercial technologies, as well as prototype efforts. A Prototype Project is defined at 10 USC 4022(e)(5) as a project that addresses: (A) a proof of concept, model, or process, including a business process; (B) reverse engineering to address obsolescence; (C) a pilot or novel application of commercial technologies for defense purposes; (D) agile development activity; (E) the creation, design, development, or demonstration of operational utility; or (F) any combination of subparagraphs (A) through (E).Awarding Instrument:This solicitation will be awarded in accordance with the NAVWAR CSO process detailed within N00039-25-S-0001 (NAVWAR CSO), posted to SAM.gov on 4 JUN 2025. This document can be found at: https://sam.gov/opp/a606b587755240e1a0b4f7d1e8d557bc/viewPlease refer to NAVWAR CSO for additional information regarding the three-phase process:Phase 1: Solution BriefsPhase 2: Pitch SessionPhase 3: ProposalVendors are reminded that in order to utilize an Other Transaction (OT) agreement the requirements of 10 USC 4022(d) must be satisfied: (A) There is at least one nontraditional…