BIGST-BAA_Topic_3_VLBIG_20240508.docx

UNCLASSIFIED

BIG-ST BAA HM047623BAA0001

Topic 03: VLBI+G

BIG-ST BAA HM047623BAA0001

Topic 03: VLBI+G

BIG-ST BAA (HM0476-23-BAA-0001)

Topic # 003 –VLBI+G Signal Chain Development

For instructions on submission of abstracts and proposals and evaluation of proposals, please review BIG-ST BAA General Solicitation (HM047623BAA0001).

Document Change History Table 1 - Document Change History

Title Very Long Baseline Interferometry with Global Navigational Satellite Systems Capabilities (VLBI+G) Radio Telescope Signal Chain Development Expected Awards Intent of this topic call is to award an Other Transaction (OT) Agreement.

The Government plans to make one OT award for this topic call, but may make more than one or none, based both on the quality of the submissions and the availability of funding.

Budget The estimated range for the base and option period is as follows:

Base (21 months): $1.7M to $2.5M Option Period (06 months): $500K to $1.5M This competition for a prototype OT permits the subsequent award without competition of a follow-on production contract/agreement, contingent upon successful completion of the prototype award in accordance with 10 U.S.C. § 4022. That authority notwithstanding, the decision to award a follow-on contract/agreement is in the sole discretion of the Government.

Topic Technology Readiness Level (TRL) This BAA Topic call is limited to projects that fall within TRL range 3-5 at the start of this effort. Proposed development efforts shall yield a TRL range 5-6 at the end of the base period, and at a minimum meet the definition of TRL 6 at the end of the option period.

Point of Contact (POC) Please send all questions and submissions to the Contracting Officer (CO): Daniela Garavito Email Address: BIGSTBAA@nga.mil ➔ Use the following email subject for all email correspondence: ‘TOPIC 03 – VLBI+G’ Dates Table 2 - Dates

Eligibility Consistent with 10 U.S.C. § 4022, the awardee for this prototype OT must meet at least one of the following requirements:

(A) There is at least one nontraditional defense contractor or nonprofit research institution participating to a significant extent in the prototype project.

(B) All significant participants in the transaction other than the Federal Government are small businesses (including small businesses participating in a program described under section 9 of the Small Business Act (15 U.S.C. § 638)) or nontraditional defense contractors.

(C) At least one third of the total cost of the prototype project is to be paid out of funds provided by sources other than the Federal Government.

For the purposes of this topic call, vendors must self-certify their qualification under 10 U.S.C. § 4022 in the Government-provided cover sheet (see BIG-ST BAA General Solicitation, Appendix 2 Proposal Template) by adding the following statement at the end of the cover sheet and checking the applicable checkbox:

<Insert company name> herby certifies that ☐ The vendor is a nontraditional defense contractor or nonprofit research institution participating to a significant extent in the prototype project.

☐All significant participants in the transaction other than the Federal Government are small businesses (including small businesses participating in a program described under section 9 of the Small Business Act (15 U.S.C. 638)) or nontraditional defense contractors.

☐The vendor will provide at least one third of the total cost of the prototype project to be paid out of funds provided by sources other than the Federal Government.

The Government reserves the right to confirm a vendor’s certification, whether by independent inquiry into the facts or by requesting appropriate documentation from the vendor. Any vendor that fails to self-certify, or otherwise demonstrate compliance with this requirement to the Government’s satisfaction, will be deemed ineligible for award without further Government review of the proposal.

Topic Research Opportunity Description This topic call seeks to develop an enhanced VLBI+G signal chain capability that can work in a network of existing VLBI systems to collect observations useful in supporting production of the Terrestrial Reference Frame (TRF) and Earth Orientation Parameters (EOP).

The VLBI+G signal chain capability shall be installed and tested in a Calian 12-meter radio telescope. If the prototype OT is successful, production version may call for installation on a General Dynamics 14-meter antenna.

Background and Purpose General The Geodesy mission of NGA’s Mapping, Charting and Geodesy (MC&G) domain is to better understand the earth to improve navigation, mapping, charting, tides, and geodetic products as called out in U.S. Code Title 10. To address this mission, NGA created the World Geodetic System (WGS). NGA’s WGS is a system of geodetic systems; at its heart is the TRF.

Geodesy is a science that studies the size, shape, gravitational field, motion, and orientation of the earth in space. Geodesy also analyzes the listed properties change over time relative to the stars and their individual gravitational fields. The earth’s orientation and motion through space is defined relative to the stars that are in the celestial sphere. A location on this celestial sphere is defined in terms of its coordinates in the Celestial Reference Frame (CRF), similar to the earth’s latitude and longitude system used to plot positions within the TRF.

The TRF is generated through accurately determined coordinates of a set of reference stations. It starts at the center of mass of our planet, while the coordinates of the reference stations implicitly define the scale of the TRF and the orientation of its axes. Since the earth is a dynamic planet with constantly moving continental plates, the TRF must be monitored and maintained as our planet changes.

VLBI uses observations of two or more radio telescopes observing the same very distant quasars (i.e., extremely luminous active galactic nucleus) to determine the orientation of the baseline between the telescopes with respect to the quasars to determine the EOP that define the relationship between the TRF and the CRF. These VLBI observations can also be used in the defining of the TRF’s scale. While Global Navigation Satellite Systems (GNSS) were principally designed to aid navigation and positioning, GNSS satellites can also be used in monitoring the earth’s polar motion, two of the EOP parameters.

Purpose

2.1.1 Mitigate differences between VLBI and GNSS space measurements to improve accuracy and maintenance of TRF and EOP Generation and maintenance of the TRF and EOP requires geodetic observations using different techniques. One technique is VLBI, which determines the earth’s orientation in relation to the CRF and scale of the frame and data from GNSS satellites.

However, when comparing the EOP determined from VLBI and GNSS observations, the results do not agree based on measurement errors in each of the observing approaches. One source of the discrepancies is the GNSS satellite antenna phase center error, which contributes to the difference between the GNSS network frame and the VLBI network frame. In addition to this error, another primary source of error in geodetic VLBI is water vapor delay due to water in the atmosphere.

Studies indicate that reconciling the differences between VLBI and GNSS measurements will improve accuracy while maintaining TRF and EOP accuracy. Sample approaches to address measurement error sources include:

· Modification of the existing VLBI Geodetic Observing System (VGOS) to add the capability to observe GNSS satellites or to build new VLBI telescopes with GNSS capabilities, hereby referred to as VLBI+G. This would allow the VLBI antenna to observe very distant quasars and earth-orbiting GNSS satellites. Since both the ground-based GNSS receiver antenna and the VLBI+G antenna would be observing the same GNSS satellite broadcast message, which is emitted from satellite antenna’s phase center, it is expected that the phase center error at the GNSS satellite antenna is greatly reduced and possibly even removed.

· Enablement of differential measurements between the VLBI antenna and a small local directional GNSS antenna to establish gravitational and thermal models for the VLBI antenna and to establish and monitor intra-site ties. Observation of GNSS satellites with a VLBI antenna is then expected to result in improved GNSS orbits by tracking them directly in the inertial frame defined by the CRF.

Introduction of a VLBI system with the capability to observe frequencies between 18 and 24 GHz would allow the system to directly monitor the atmospheric water vapor content while making observations. This is expected to be useful in reducing the correction error due to water vapor delay within the VLBI observations.

Details of expected improvements in accuracy are listed in section 4, Performance Metrics, of this topic call.

2.1.2 Develop a 1.15 GHz to 24 GHz VLBI frontend, with selectable 512 MHz and 1024 MHz bandwidths, to allow for GNSS transmission collection and water vapor delay corrections in observations

Other issues with the current VLBI is the intrusion of other radio frequency (RF) signals (e.g., 5G cellular networks into X-band), and the correction of water vapor delays in observations using radiometers or atmospheric models. The solution to these issues is the introduction of a VLBI+G frontend with an expanded frequency range that includes 18.7 to 23.8 GHz bands.

This topic call seeks to expand the VGOS frequency range from 2.0 to 14 GHz to a broader range of 1.15 to 24 GHz, with selectable 512 MHz and 1024 MHz bandwidths, that allows for collection of GNSS, quasars, and atmospheric water vapor emissions at the same time.

Project Structure/Scope Vendors shall construct their project into two phases, namely base and one option period.

The proposal shall provide a clear breakdown for each phase, showing how the vendor intend to achieve the objective of this topic, along with a schedule that indicates proposed achievements of program milestones. Vendors shall include in the proposal the assumption of holding a progress review and status meeting with the Government at least monthly.

3.1 Base Period: Design, Develop, and Build (up to 21 months):

· The main objective of Phase 1 is for the awardee to design and build the entire VLBI+G signal chain (front-end to back-end) capability for detecting and recording emissions from GNSS satellites and distant quasars, meeting the performance requirements listed in Section 4 of this Topic Call.

· The awardee shall provide the deliverables listed in Section 5 of this topic call.

· Documentation and system specifications will be refined throughout the program, based on inputs from government personnel and performers, to ensure that the resulting VLBI+G satisfies the needs of NGA and its customers.

3.2 Option Period: Installation, Calibration, and Testing (up to 6 months) In the option period, awardee shall install, calibrate, and test the new VLBI+G signal chain system into a Calian (formerly Intertronic), 12-meter radio telescope, and then calibrate and test the new signal chain.

· A successful development effort will result in a VLBI+G signal chain that can:

· Collect observations of GNSS satellites between 1.2 GHz and 1.62 GHz.

· Perform at the level of a 12-meter VBLI Geodetic Observing System (VGOS) station in the 2 GHz to 14 GHz frequency bands.

· Collect water vapor lines and temperature profile of the water vapor between 18 and 24 GHz.

· After installation of the enhanced VLBI+G signal chain into the radio telescope, the performer shall calibrate the signal chain with in the telescope on site in accordance to calibrations used for VGOS, with additional calibrations to demonstrate the performance of the signal chain within the GNSS frequency and water vapor bands, between 18 GHz and 24 GHz.

· Performer On-site Testing shall include:

· A demonstration that the performance metrics within Section 4 below are met or exceeded.

· Validation of the new enhanced VBLI+G signal chain system with another GPS capable VLBI system, such as the one at MIT Haystack Observatory, to demonstrate the GNSS interferometric observing capability of GNSS satellites.

· Demonstrate against a VGOS system that is unable to observe the water vapor bands, the ability of the new VLBI+G enhancement to correct for observed water vapor in the atmosphere.

· Results of performer on-site performance testing shall be provided to the Government prior to NGA’s evaluation of VLBI+G signal chain.

· The awardee shall hold a training session for up to ten individuals selected by the Government. At the training session, the awardee shall provide each attendee a copy of the final operating instructions, in both digital and paper form. The awardee shall confer with the Government prior to the training session to establish the file format and delivery medium for the digital version.

At the conclusion of the Option Period, the awardee shall provide NGA with a firm fixed-price quotation and notional schedule for a follow-on production OT to deliver up to five additional enhanced VLBI+G Signal Chains systems.

3.3 Outside the Scope of this Topic

This Topic Call specifically addresses NGA Research and Development funding solutions that propose the design, development, build, installation, calibration, and testing of VLBI having extended frequency support (for observance of GNSS satellite broadcast signals and atmospheric water vapor emissions between 18 GHz and 24 GHz bands). Submissions outside this scope are not responsive to the Topic Call, and are ineligible for award.

Performance Metrics The overarching goal of this topic call is to design, build, calibrate, and test an enhanced VLBI+G signal chain in a Calian 12 -meter radio telescope dish and mount provided by the government, in a site within the contiguous US, in accordance with following performance requirements.

Performers shall meet the following metrics:

Table 3 - Enhanced VLBI+G Signal Chain Performance Requirements

QRFH Bandwidth

20:1

Ratio

Less than 10 dB

Low Noise Amplifier (LNA) Bandwidth

20:1 dB

Bands 2.0 GHz - 16.0 GHz Bands 16.0 GHz - 24+ GHz

Less than 250 Less than 250 Less than 500

Jy* mJy mJy

MHz-wide

MHz-wide

MHz-wide

* 1 Jansky = 1 x 10-26 W/m2/Hz

Deliverable Items All Reports and briefings shall be provided to NGA’s Program Manager (PM) and Agreement Officer (AO) in the form of emails, briefings, and/or reports that clearly detail progress made and any challenges, issues, and findings. Also, the performer shall provide in all documentation and test results any written comments and recommendations. The performer and NGA shall send documents via the U.S. Army Aviation and Missile Research Development and Engineering Center’s Safe Access File Exchange (AMERDEC SAFE) or similar unclassified system capable of encrypted emails. All documents shall be delivered in a format customarily used for the information presented. The awardee may confer with the Government POC regarding preferred file format as needed.

Monthly technical reports shall be delivered 24 hours prior to a monthly teleconference to NGA PM, AOR, and AO, to allow review of the report before the teleconference. The teleconference will be held at a mutually agreed-upon time.

The VBLI+G signal chain system—together with the software required for system operations—shall be delivered and installed at an NGA-determined site within the continental United States. The site selection process will be completed prior to the base period Mid-Point Review.

Table 4 – Base Period Deliverables Base Period

Table 5 – Option Period Deliverables

Option Period

Intellectual Property Considerations NGA will negotiate IP and ownership as part of the OT.

Government Furnished Information/Data/Property

Security Considerations Work under this effort will be up to the UNCLASSIFIED level.

8.1 Unclassified Work Performance Security Requirements

Uncleared awardee personnel are authorized to work on this agreement at the Unclassified level without the requirement of a security clearance.

8.2 Uncleared Personnel Security Requirements

Foreign nationals are not permitted to perform unclassified work under the terms of this agreement without prior written approval from the Agreements Officer (AO) or Agreements Officer's Representative (AOR). Should NGA identify the use of unauthorized personnel, the AO may direct the awardee, at its own expense, to remove and replace any unauthorized awardees, sub awardees, or other personnel performing on the agreement. Such action may be taken at the NGA's discretion without prejudice to its rights under any other agreement provision, e.g. termination for default.

8.3 Information Security Requirements

NGA shall have the sole authority to determine whether, and to what extent, protected information shall be provided to the awardee under the terms of the agreement. The awardee shall not access, download, print, or further disseminate any unclassified information outside the execution of the defined agreement requirements without the guidance and written permission from the AOR.

Awardee personnel shall not release any unclassified information, regardless of medium (e.g., film, tape, document), pertaining to any part of this agreement or any program related to this agreement, unless the AOR has given prior written approval or in performance of a project that has been scoped and negotiated by NGA.

NGA will assess and authorize awardees to process unclassified information on government-owned information systems, conduct oversight of such information system processing, and provide information system security guidelines and other information system security control policies, standards, and procedures.

Performance

10.1 . Place of Performance:

Installation and testing will occur at an NGA determined site within the contiguous U.S.;

NGA will provide location prior to the base period mid-point review.

10.2. Period of Performance (PoP):

Base Period: Twenty-one Months Option Period: Six Months