Multiple Telemetry Site Signal Source Synchronization

Flight test missions that traverse multiple Test Ranges (e.g. hypersonic vehicles/weapons, cruise missiles, long-range weapon systems etc.) or that require different test support infrastructures (e.g. sea range, targets, threat simulators, etc.) at remote Test Ranges, require telemetry receive stations along the flight paths to receive real-time telemetry and then relay that data via ground networks to the control room monitoring the mission. In past mission pre-flight scenarios, remote telemetry receive site to control room links were checked individually. This was accomplished with a local bore sight signal simulator that transmitted a known test pattern at the center frequency of the actual test article. The telemetry receive site would receive the radio frequency signal, demodulate/decode it, then send the data via Internet protocol (IP) networks to the control room. In the control room the received data was verified to be correct as the bit pattern received could be compared to the bit pattern transmitted. This was accomplished for each local and remote telemetry receive site prior to the mission.During the test, each local and remote telemetry receive site would send data to the control room and a manual switch would be accomplished between each data source based on data quality that was determined manually. Note, this selection was not automated.With the invent of best source selection using data quality metrics transferred over IP networks via data quality encapsulation [1], no longer is election of multiple data sources done manually. Telemetry receivers now assess received data quality and assign a bit error probability to a packet of data prior to sending it to the best source selector in the control room. A best source selector (BSS) inputs these multiple streams, performs time alignment, then using the data quality metric, selects the best data to output on a bit-by-bit basis. This output is the best data using all available data streams from diverse receive sites.Though higher quality, near error-free data is now provided to the control room, the addition of the BSS has revealed a shortfall. The entire data path from remote receive sites to transport through best source selection to control room cannot be tested as a complete system to assess mission readiness. The traditional method of pre-flight checks cannot be used. Why? The best source selector will not be able to correlate the multiple data streams from remote sites as the signal sources will not be correlated. This results in the configuration and operation of the BSS being unknown until the test mission. The proposed work will focus on solving this shortfall resulting in a networked, synchronized telemetry validation system capable of simulating a test vehicle's telemetry signal at multiple ground stations simultaneously. Stated another way, the proposed system must simulate the test article signal as if all telemetry receive stations could "see" the test article and simultaneously receive the telemetry signal. This capability will allow test ranges to perform pre-mission verification of the entire telemetry infrastructure. This would include all participating receive antennas, distribution networks, and best source selector(s) to control room displays to ensure full system connectivity and performance before supporting a live mission.

Objective

The objective of this project is to study, develop, test, and field a system that addresses a critical gap in pre-mission verification and validation of receive systems supporting flight test missions that transition between multiple, geographically diverse Test and Training Ranges. The end goal is to achieve a fully operational system that enables synchronized telemetry test signals across all participating ranges. This will allow for a comprehensive, end-to-end system checkout before a live test, significantly reducing operational and data fidelity risks, enhancing test accuracy, and strengthening mission readiness for advanced DoW test scenarios.

Phase I

Phase I should assess the scientific and technical merit and feasibility of the concept proposed for Inter-Range telemetry receive system synchronization and signal source correlation. Objectives and expectations in Phase I are as follows: Thoroughly describe the shortfall identifying all components and interfaces. Reference all appropriate standards and provide a use case(s) that clearly illustrates the shortfall.Propose an architecture that addresses and solves this shortfall. A solution should provide a solution that incorporates multiple, spatially diverse telemetry signal sources/simulators and synchronizes these sources with precise, common time and frequency reference across all sites.Derive a master-client network architecture with a centralized command and control graphical user interface. This will allow an operator to remotely configure, manage, and monitor all signal sources/simulators from a centralized location.At the core of this solution, develop a protocol that precisely aligns all remote pseudo-random bit sequences (PRBS) generated by each simulator.

Phase II

The Phase II effort will focus on the research, development, and delivery of a prototype system. The principal objectives include:Objective 1: Telemetry Signal Synchronization: Develop a master-client protocol and integrate a timing solution to achieve time-aligned signal generation across multiple remote telemetry signal simulators.Objective 2: Command and Control: Implement a web-based graphical user interface (GUI) for centralized configuration, status monitoring, and control of all remote simulators from a single centralized interface.Objective 3: Multi-Site Telemetry Signal Source Verification and Testing: Demonstrate multi-site correlation through bit error rate (BER) testing integrating best source selection (BSS). This includes simulating real-world impairments such as network latency and jitter. This can be simulated or with actual hardware (see Objective 4).Objective 4: Lab Verification of Hardware: Demonstrate proposed hardware in a lab environment.Objective 5: In the Field Validation of Hardware: Demonstrate the prototype system, consisting of a minimum of three signal sources controlled via a central control hub. The prototype system will be installed and tested at three geographically diverse locations. For example, that can be three sites at one Range, or one site at three Ranges (e.g. Edwards AFB, China Lake Range, Pt. Mugu Sea Range).Success criteria will be based on the system's ability to achieve and maintain PRBS synchronization of the three remote signal simulators, successful execution of remote commands via the GUI, and passing multi-site BER testing at the output of the BSS.

Phase III

The Phase III effort will focus on transitioning the prototype system to a fully operational and commercially available and sustainable product. Technology is expected to enter Phase III at TRL-6 and be matured to TRL-8. Working with the Test Ranges will be key to this maturation as real-world testing will aid in process. Direct interaction with the Telemetry Group of the Range Commanders Council will ensure customer needs are integrated into the hardware as it is matured. A successful SBIR Program would result in the standardization of the end product in the Telemetry Standard IRIG-106 with adoption into the major Test Ranges.DoW Applications: The end goal for this system would be to secure procurement contracts via the SBIR Phase III pathway to deploy the end system as a standardized solution across Air Force, Army, and Navy Test Ranges. Known customer opportunities include the 412th Test Wing (Edwards AFB), 96th Test Wing (Eglin AFB), NAWCAD (Point Mugu and Patuxent River), and White Sands Missile Range as all support flight test programs that require range airspace and assets spanning multiple Ranges.Commercial Applications: Market the end system to commercial aerospace prime contractors (e.g., Boeing, Lockheed Martin) and commercial space launch providers (e.g., SpaceX, Blue Origin, ULA) to improve the efficiency and reliability of their own flight-testing programs.Business Model: The commercialization strategy will blend direct sales to DoD ranges with commercial applications.

Keywords: Signal Synchronization; Integrated Network Systems; Best Source Selection; Test and Training Ranges; Flight Test Missions; Data Quality Metrics; Hypersonic Vehicles; Real-Time Data; System Validation; Telemetry Infrastructure; DoW Test Scenarios

Technology areas: Battlespace, Electronics, Information Systems, Sensors, Weapons

Focus areas: Integrated Network Systems-of-Systems, Integrated Sensing and Cyber, Space Technology

CMMC level: Level 2 (Self)