N231-042 TITLE: Pressure-Tolerant Electronically-Steered Antennas (ESAs) for Satellite Communications on Unmanned Undersea Vehicles (UUV)

OUSD (R&E) CRITICAL TECHNOLOGY AREA(S): Cybersecurity; Networked C3

OBJECTIVE: Develop pressure-tolerant electronically-steered antennas (ESAs) to enable high data rate communications on Unmanned Undersea Vehicles (UUVs).

DESCRIPTION: The Navy is looking to pressure-tolerant ESAs for use on UUVs to facilitate the sending and receiving of large data sets in far forward and open-water locations. The commercial market lacks steerable antennas appropriate for UUV integration. Breakthrough advances in silicon technologies in recent years have enabled a significant increase in capability of ESAs, such as but not limited to, phased array antennas, while per-element costs have also been greatly reduced. The Navy looks to leverage these recent advances to develop pressure-tolerant ESAs for UUVs. The closest commercial equivalents would be planar phased arrays used in terrestrial applications. Such arrays are not suitable for UUV applications targeted by the Navy, as they are not able to withstand hydrostatic pressures. Other Navy Satellite Communications (SATCOM) applications use mechanically pointed gimballed dish antennas, but dish antennas must be housed in air-backed radomes to withstand hydrostatic pressure, and they occupy a large volume on the target platform.

Maximizing aperture area, while making a mechanically robust ESA, will be challenging, posing unique mechanical and electrical design constraints. Additionally, the ESA must have as large an antenna aperture area as possible, which drives designs with minimum mechanical structure. The ESA must also provide high radio frequency (RF) performance coupled with electronic steering capabilities to track fast-moving Proliferated Low Earth Orbit (PLEO) satellites as they pass in/out of view. In addition to enabling transfer of large data sets, PLEO Data links will enable use of High Assurance Internet Protocol Encryptor (HAIPE) network devices, enabling encrypted data links.

Current commercial UUV transmit/receive antennas project omni-directional RF energy in all directions, whereas ESAs are generally limited to larger manned platforms such as surface vessels and aircraft. Development of pressure-tolerant ESAs compatible with size, weight, and power (SWaP) constraints of UUVs is challenging. The available SWaP within UUVs varies greatly by class and design, but rough order of magnitude (ROM) allowances are provided in the table below. It is noted that the values in this table are provided for guidance only � they are not to be considered formalized requirements against which the proposals will be adjudicated. Additionally, it is noted that these ESAs are primarily targeted for large and extra-large UUVs, but will also be considered for medium UUVs, if sufficient RF performance can be achieved within the SWaP constraints listed.

Pressure-Tolerant Electronically-Steered Antennas (ESAs)

for Satellite Communications on Unmanned Undersea Vehicles (UUV)

UUV Class	Medium	Large	Extra-Large
ROM Volume	216 in3 (6" cube)	1728 in3 (12" cube)	5832 in3 (18" cube).
ROM weight in air	5 lbs	64 lbs	216 lbs
ROM Operating Power (W)	250 W	350 W	500 W
ROM Standby Power (W)	5 W	10 W	20 W
ROM Seawater Pressure Tolerance (psig)	870	1,000	1,000

 

These SWaP challenges are exacerbated by the requirement to withstand large hydrostatic pressures experienced during UUV missions. Larger surface areas are required to get the desired RF performance, so a prime challenge is optimizing the ESA to fit within the existing UUV platforms. Another challenge is the pointing of the beam: it is desirable to support multiple simultaneous links across the full band, with beam steering accomplished through a fully solid-state design. If this (full solid-state beam pointing) is not achievable, then pointing can be achieved with minimal mechanical steering. The desired RF performance attributes include:

a) Tunable across 5 � 33 GHz frequency range

b) G/T of at least 10 dB/K in Ku and K bands

c) EIRP of at least 36 dBW gain in 10 � 15 GHz freq range and 38 to 43 dBW in Ka Band

d) Ability to receive GPS (L1, L2, L5)

 

In addition to RF performance, proposers should include the pointing method of the resultant beam(s), the control of the beam�s side lobes, and the main lobe width(s), while minimizing size, weight, power, and cooling (SWaP-C) associated with the solution. Proposers should also highlight the novelty of their approach.

The technical merit of the proposed solutions will be evaluated on factors including:

1. G/T and EIRP over the 5 � 33 GHZ frequency range

2. Ability to support multiple simultaneous links across the full band (5-33 GHz) to include multiple Low Earth Orbit (LEO)/Medium Earth Orbit (MEO) constellations

3. Estimated unit cost per ESA

4. Maximum volume and maximum aperture dimension

5. Estimated weight of the system

6. Beam steering methodology: solid state or minimal mechanical steering

7. Maximum power draw by the array when in use and during standby

8. Suitability of array design to operate/survive over the variety of operational depths over which PEO-USC UUVs operate

 

Work produced in Phase II may become classified. Note: The prospective contractor(s) must be U.S. Owned and Operated with no Foreign Influence as defined by DOD 5220.22-M, National Industrial Security Program Operating Manual, unless acceptable mitigating procedures can and have been implemented and approved by the Defense Counterintelligence Security Agency (DCSA), formerly the Defense Security Service (DSS). The selected contractor must be able to acquire and maintain a secret level facility and Personnel Security Clearances, in order to perform on advanced phases of this contract as set forth by DCSA and NAVSEA in order to gain access to classified information pertaining to the national defense of the United States and its allies; this will be an inherent requirement. The selected company will be required to safeguard classified material IAW DoD 5220.22-M during the advance phases of this contract.

All DoD Information Systems (IS) and Platform Information Technology (PIT) systems will be categorized in accordance with Committee on National Security Systems Instruction (CNSSI) 1253, implemented using a corresponding set of security controls from National Institute of Standards and Technology (NIST) Special Publication (SP) 800-53, and evaluated using assessment procedures from NIST SP 800-53A and DoD-specific (KS) (Information Assurance Technical Authority (IATA) Standards and Tools).

The Contractor shall support the Assessment and Authorization (A&A) of the system. The Contractor shall support the government�s efforts to obtain an Authorization to Operate (ATO) in accordance with DoDI 8500.01 Cybersecurity, DoDI 8510.01 Risk Management Framework (RMF) for DoD Information Technology (IT), NIST SP 800-53, NAVSEA 9400.2-M (October 2016), and business rules set by the NAVSEA Echelon II and the Functional Authorizing Official (FAO). The Contractor shall design the tool to their proposed RMF Security Controls necessary to obtain A&A. The Contractor shall provide technical support and design material for RMF assessment and authorization in accordance with NAVSEA Instruction 9400.2-M by delivering OQE and documentation to support assessment and authorization package development.

Contractor Information Systems Security Requirements. The Contractor shall implement the security requirements set forth in the clause entitled DFARS 252.204-7012, "Safeguarding Covered Defense Information and Cyber Incident Reporting," and National Institute of Standards and Technology (NIST) Special Publication 800-171.

PHASE I: Develop a concept for a directional acoustic transmitter that meets the requirements in the Description. Establish feasibility by developing system diagrams, as well as Computer-Aided Design (CAD) models that show the ESA concept and provide estimated weight and dimensions of the concept. Feasibility will also be established by computer-based simulations that show the antenna�s RF performance and pointing capabilities are suitable for the project needs. The Phase I Option, if exercised, will include the initial design specifications and capabilities description to build a prototype solution in Phase II.

PHASE II: Based on the results of Phase I and the Phase II Statement of Work (SOW), develop and deliver a prototype system for in-situ (on water) testing and measurement/validation of the Phase I performance attributes. Test the prototype system, first in a controlled laboratory environment, then in an on-water environment, to determine its capability to meet all relevant performance metrics outlined in the Phase II SOW. Testing shall characterize the RF and beam pointing performance, coupled with the communication function required for closing links with various commercial SATCOM providers. The ability to meet the hydrostatic pressure tolerance requirements shall be demonstrated by analysis or testing. Demonstrate the prototype system�s performance in both environments (laboratory and in-water) to the Government and present the results in two separate test reports. Use the results to correct any performance deficiencies and refine the prototype into a pre-production design that will meet Navy requirements. Prepare a Phase III SOW to transition the technology to Navy use.

It is probable that the work under this effort will be classified under Phase II (see Description section for details).

PHASE III DUAL USE APPLICATIONS: Support the Navy in transitioning the technology to Navy use and support further refinement and testing of the ESA functionality following successful prototype development and demonstration. If successful, in addition to UUV applications, these ESAs could be applied to other unmanned Navy assets including buoys, subsea nodes, and unmanned surface vehicles (USVs). In addition to such DoD applications, these antennas could be used in commercial oil, gas, and oceanographic sensing applications, where the exchange of large data sets is required.

REFERENCES:

1.       G. He, X. Gao, L. Sun and R. Zhang, "A Review of Multibeam Phased Array Antennas as LEO Satellite Constellation Ground Station," in IEEE Access, vol. 9, pp. 147142-147154, 2021, doi: 10.1109/ACCESS.2021.3124318. https://ieeexplore.ieee.org/document/9594858

2.       J. B. L. Rao, R. Mital, D. P. Patel, M. G. Parent and G. C. Tavik, "Low-cost phased array antenna for satellite communications on mobile earth stations," 2013 IEEE International Symposium on Phased Array Systems and Technology, 2013, pp. 214-219, doi: 10.1109/ARRAY.2013.6731829. https://ieeexplore.ieee.org/document/6731829

3.       K. Vivek Raj, S. Ranjitha, V. Meghana and H. Preethi, "Satellite Tracking Using 7X7Hexagonal Phased Array Antenna," 2019 4th International Conference on Recent Trends on Electronics, Information, Communication & Technology (RTEICT), 2019, pp. 369-374, doi: 10.1109/RTEICT46194.2019.9016813. https://ieeexplore.ieee.org/document/9016813

4.       I. M. Elbelazi and M. C. Wicks, "Receiving Frequency Diverse Array Antenna for Tracking Low Earth Orbit Satellites," 2019 IEEE National Aerospace and Electronics Conference (NAECON), 2019, pp. 698-701, doi: 10.1109/NAECON46414.2019.9057984. https://ieeexplore.ieee.org/document/9057984

 

KEYWORDS: Electronically Steerable Antennas; ESAs; Phased Arrays; Unmanned Undersea Vehicles; UUVs; Data Exfiltration; High Data Rate; Proliferated Low Earth Orbit Satellite Communication; PLEO

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