HR001119S0035-18.pdf

Small Business Innovation Research (SBIR) and Small Business Technology Transfer

(STTR)

Opportunity Announcement

HR001119S0035-18

Distributed mm-Wave Full Duplex Two-Way Time Transfer

Which program will fund this topic?

SBIR

What type of proposals will be accepted?

Direct to Phase II (DP2) Only

Technology Area(s): Sensors, Electronics, and Electronic Warfare

I. INTRODUCTION

The Defense Advanced Research Projects Agency (DARPA) Small Business Programs Office (SBPO) is issuing an SBIR/STTR Opportunity (SBO) inviting submissions of innovative research concepts in the technical domain(s) of Sensors, Electronics, and Electronic Warfare. In particular, DARPA is interested in understanding the feasibility of Distributed mm-Wave Full Duplex Two-Way Time Transfer as it relates to communications between fast moving platforms with a large amount of Doppler shift.

This SBO is issued under the Broad Agency Announcement (BAA) for SBIR/STTR, HR001119S0035. All proposals in response to the technical area(s) described herein will be submitted in accordance with the instructions provided under HR001119S0035, found here:

https://www.fbo.gov/spg/ODA/DARPA/CMO/HR001119S0035/listing.html

a. Eligibility The eligibility requirements for the SBIR/STTR programs are unique and do not correspond to those of other small business programs. Please refer to Section 3.1, Eligible Applicants, of HR001119S0035 for full eligibility requirements.

b. Anticipated Structure/Award Information Please refer to Section 1, Funding Opportunity Description provided in HR001119S0035 for detailed information regarding SBIR/STTR phase structure and flexibility.

Proposers should provide adequate documentation to substantiate that the scientific and technical merit and feasibility described in the Phase I section of the topic have been met and describe the potential commercial applications. The Direct to Phase II (DP2) authority allows the Department of Defense (DoD) to make an award to a small business concern under Phase II of the SBIR program without regard to whether the small business concern was provided an award under Phase I of an SBIR program. This SBO is accepting DP2 proposal submissions ONLY.

For this SBO, DARPA will accept DP2 proposals only, for cost of up to $2,250,000. This includes an 18-month base period not to exceed a cost of $1,500,000 and a 12-month https://www.fbo.gov/spg/ODA/DARPA/CMO/HR001119S0035/listing.html option period not to exceed a cost of $500,000. A separately priced option of up to $250,000 must also be proposed for contractors who would like to be considered for participation in the DARPA Embedded Entrepreneur Initiative. Refer to Section 2.5, DARPA Embedded Entrepreneur Initiative, of HR001119S0035 for detailed information on EEI.

Proposers should refer to Section 4, Application and Submission Information, of HR001119S0035 for detailed proposal preparation instructions. Proposals that do not comply with the requirements detailed in HR001119S0035 and the research objectives of this SBO are considered non-conforming and, therefore, are not evaluated nor considered for award.

DP2 Feasibility Documentation shall not exceed 40 pages. DP2 Technical Proposal shall not exceed 40 pages. Phase II commercialization strategy shall not exceed 5 pages. It should be the last section of the technical volume and will not count against the 40-page limit. Please refer to Appendix B of HR001119S0035 for detailed instructions on DP2 Proposal Preparation.

c. Evaluation of Proposals Section 5, Evaluation of Proposals, in HR001119S0035 provides detailed information on proposal evaluation and the selection process for this SBO.

d. Due Date/Time Full proposal packages (Proposal Cover Sheet, Technical Volume, Price/Cost Volume inclusive of supporting documentation, and Company Commercialization Report) must be submitted via the DoD SBIR/STTR Proposal Submission website per the instructions outlined in HR001119S0035 no later than October 10, 2019 at 2:00 PM E.T.

II. TOPIC OVERVIEW

a. Objective

Establish full duplex frequency-phase alignment at mm-wave by demonstrating the feasibility of two-way time transfer (TWTT) with a low-latency analog radio frequency (RF) front end to achieve coherence up to Ka Band, even with high Doppler shifts. This would enable two-way timing synchronization among distributed mobile users for many edge applications in the anti-access area-denial (A2AD) environment in the absence of external third-party reference synchronizing signals.

b. Description Current approaches to distributing time and frequency across a communications link rely on microwave transmission or free space optical transmission of clock information between clocks with high accuracy. Both RF and optical approaches are negatively affected by time of flight variations and Doppler shifts associated with rapidly varying link distances. Optical methods may ultimately provide higher resolution but are easily blocked by the relative instability of the medium.

Current RF time duplexing approaches to lock frequency and phase of mobile nodes together are limited to low operating frequencies below L-band and are not suitable to link high velocity nodes. These implementations also require expensive Oven-controlled Crystal Oscillators (OXCOs), and energy hungry digital signal processors, which are not scalable for operations in small platforms at millimeter-wave frequencies.

DARPA is seeking innovative techniques that would provide an RF approach to two-way frequency and phase synchronization of ultra wideband millimeter-wave signals between two fast-moving mobile units operating in a non-dispersive channel. The approach should focus on synchronizing wideband millimeter signals operating at 30 GHz with a 10 GHz instantaneous bandwidth. In order to be embedded in a compact mobile platform with constrained energy supply, application-specific integrated circuits (ASICs) based on energy efficient analog approaches with minimal digital processing elements and low cost oscillators instead of OCXOs are desirable and expected.

Compared with current mobile L-band operation, proposed approaches should produce 10X higher frequency carriers to operate at Ka band with 1,000X faster refresh rate, and 10X better timing accuracy with < 20 ps error over >30 seconds under a multi-path environment. This will require a 25X lower latency (<10 µs) to operate at delta velocities between two nodes up to Mach 2. Proposed implementations should only rely on low cost reference oscillators and be capable of implementation in a low size, weight, and power (SWAP) CMOS chip without ultrafast, power hungry ADCs.

The emerging ultra wideband communication application needs timing synchronization among mobile users over an ultra-wide operating bandwidth to mm-wave regime. The key concepts developed in this topic will support the new applications which rely on accurate TWTT to establish broadband communications. The fast, low latency synchronization will enable processing of complex signaling for agile cognitive communication, as well as edge sensing in future DARPA programs. In addition, robust TWTT will enable other DoD relevant applications such as precise position for navigation, and coherent multi-static radar.

c. Phase I This SBO is accepting Direct to Phase II proposals ONLY. In order for proposed efforts to be considered for Direct to Phase II, the feasibility documentation must demonstrate an initial concept design backed by a system simulation of the most critical blocks for a Full Duplex Phase Alignment system, supported by critical equation derivations and with a lab demonstration. Intermodulation distortion, thermal noise levels and other key impairment should be measured to demonstrate their impact on achieving phase alignment.

The demonstrated methods should prove the capability to scale beyond a pair of nodes on trimming and calibration for the required phase accuracies and the impact of multipath RF channel phase dispersion.

Demonstrated Metrics:

Operating Frequency: L band (1.6 GHz) operation with at least 200 Hz time transfer refresh rate

TWTT Timing Accuracy: < 1E-7 Hz (100 ns) Latency: 250 µs latency

d. Phase II The Phase II effort consists of a Phase II Base of 18 months and a Phase II Option of 12 months.

Phase II Base (18 months) The performer shall develop a demonstrator that performs advanced TWTT technology in a mm-wave RF frontend. The successful demonstration of the performance metrics of the base effort will enable the follow-up optional task to implement TWTT in an analog low power ASIC that should demonstrate at least 100-1000x reduction in SWAP.

Key Metrics:

• Operating Frequency: Ka band (30 GHz) operation with >200 kHz refresh rate

• Timing Accuracy: < 20 ps timing error over >30 seconds coherent time under multi-path environment

• Delta Velocity: Mach 2 with < 10 µs latency

Schedule and Milestones Month 2: Initial report on initial circuits, algorithms, and approaches to build a prototype TWTT system including projecting performance targets to achieve program metrics.

Month 6: Report on the fabrication, construction, of a prototype TWTT hardware system.

Month 12: Interim report describing programming and initial performance of prototype TWTT system.

Month 17: Demonstration of prototype TWTT in RF front end—all in analog domain to achieve distributed coherence at Ku- Ka Band with high Doppler shifts in CMOS implementation.

Month 18: Final Phase II Report summarizing results of the demonstration including final architecture, comparison with alternative state-of-the-art methodology; quantification of results when compared with the metrics of carrier quantity, delta velocity and SWAP; quantification of robustness to errors, noise, dropouts, distortions; and any other relevant points of technical discovery.

Month 18: Complete high level design and simulation of ASIC chip with performance projections prepared for ASIC fabrication of Phase II option.

Phase 2 Option (12 months) The performer shall optimize design, fabricate and test TWTT low power ASIC.

Key Metrics:

• Operating Frequency: Ka band (30 GHz) operation with >200 kHz refresh rate

• Timing Accuracy: < 20 ps timing error over >30 seconds coherent time under multi-path environment

• Delta Velocity: Mach 2 with < 10 µs latency

• SWAP Reduction: 100-1000X Lower SWAP vs proposer’s Phase II base implementation

Schedule and Milestones:

Implement chip-scale TWTT devices

Month 19: Preliminary design review on high level chip design with simulation.

Month 21: Critical design review of the full design, simulation, layout and performance verification of the TWTT CMOS ASIC.

Month 23: Tape out to IC foundry.

Month 27: Devices available.

Month 30: TWTT ASIC demonstration, delivery, test evaluation, documentation and report.

e. Dual Use Applications (Phase III) The optional efforts should transition the real-time two way time transfer technology developed in Phase II for commercial or DoD applications. For example, the technology transition would support commercial wireless applications such as providing time transfer among basestations and handsets or for the millimeter-wave backhaul data links in the LTE, 5G and 6G communication systems. The developed technologies would enable time transfer for new DoD cognitive radios and communications among smart sensors.

f. References

1. T. Celano, R. Beckman, J. Warriner, S. Francis, A. Gifford, and D. Howe, 2003, “Dynamic Two-Way Time Transfer to Moving Platforms,” in Proceedings of the 2003 IEEE International Frequency Control Symposium & PDA Exhibition Jointly with the 17th European Frequency and Time Forum (EFTF), 5-8 May 2003, Tampa, Florida, USA (IEEE), pp. 266-272.

2. Bergeron H, Sinclair LC, Swann WC, et al. Femtosecond time synchronization of optical clocks off of a flying quadcopter. Nat Commun. 2019;10(1):1819.

3. R. A. Nelson, 2002, Handbook on Relativistic Time Transfer.

4. Yi-Jiun Huang, Miho Fujieda, Hiroshi Takiguchi, Wen-Hung Tseng and Hen-Wai

Tsao, “Stability improvement of an operational two-way satellite time and frequency transfer system,” Metrologia, Volume 53, Number 2, 31 March 2016

g. Keywords Two way time transfer (TWTT), Doppler, timing, synchronization, GPS, oscillator, clock, wideband, millimeter signals, radio frequency (RF), low latency, complex signal processing, communications, edge sensing.

III. SUBMISSION OF QUESTIONS

DARPA intends to use electronic mail for all correspondence regarding this announcement.

Questions related to the technical aspect of the research objectives and awards specifically related to this SBO should be emailed to HR001119S0035@darpa.mil. Please include BAA number HR001119S0035-18 in the subject line. All questions must be in English and must include the name, email address, and the telephone number of a point of contact.

DARPA will attempt to answer questions in a timely manner; however, questions submitted within seven (7) days of the proposal due date listed herein may not be answered. DARPA will post a consolidated Frequently Asked Questions (FAQ) document. To access the posting go to: http://www.darpa.mil/work-with-us/opportunities. Under the HR001119S0035-18 summary will be a link to the FAQ. The list will be updated on an ongoing basis until one week prior to the proposal due date.

In addition to the FAQ specific to this SBO, proposers should also review the SBIR/STTR General FAQ list at: http://www.darpa.mil/work-with-us/opportunities. Under the HR001119S0035 summary will be a link to the general FAQ.

Technical support for the DoD SBIR/STTR Proposal Submission website is available Monday through Friday, 9:00 a.m. – 6:00 p.m. ET. Requests for technical support must be emailed to sbirhelp@bytecubed.com with a copy to sbir@darpa.mil.