You are here

Advanced Techniques for Lossless Compression of Target Vehicle Telemetry


OBJECTIVE: Help offset the limited bandwidth for vehicle telemetry against the increasing requests for addition telemetered truth information by using new mathematical techniques developed for video and audio or related applications and applying to telemetry encoding. A generalized methodology which can be adapted to imagery, health and status information, inertial measurement or global positioning system (GPS) position and orientation data is highly desirable but targeted approaches which are optimal for specific heterogeneous data streams but have low computational overhead and rigorous error-rejection are also sought. DESCRIPTION: As target flight tests become increasingly complex to fully exercise BMDS functionality and anchor performance, the amount of information being downlinked from target and interceptor vehicles creates significant logistical challenges simply due to bandwidth needs. Currently while some limited compression is in use, there is no broadly employed standard which can address the reduction of TM bandwidth across a full suite of MDA Target test vehicles. Generally data is PCM encoded and often the data has to be encrypted for security reasons. This solicitation is intended to provide the Missile Defense Agency (MDA) with techniques based on both traditional methods and latest art designed for applications in streaming on-line content and cyber data security. There are several factors which complicate the implementation of data compression in the MDA flight test environment. There are multiple target providers, multiple target vehicles and significant flight to flight variance in terms of available bandwidth and desired data. Possibly the primary challenges is the diversity of potential information and the increasingly demanding rates which must be supported. In addition, due to the costs of doing even a single flight test it is critical that all information be collected with the highest reliability and the lowest potential for loss of information upon correction. In the case of off-nominal flight conditions or anomalous events in flight, it is impossible to know a priori which channels of data will be most critical post-flight. As a result there is a high priority on maintaining the integrity of the data and assuring accurate transmission of all data streams. Typical types of data include: 1) Health and Status information on the motor, electronics, internal systems, payloads, etc. typically collected at 100Hz rates. 2) Imagery, visible, IR which may or may not be calibrated, typically collected at 10-50Hz rates. 3) Thermal sensor data including reference junction temperatures, as many as 100 sensors typically collected at 100Hz. 4) Body kinematic information in various forms at 100Hz rates. 5) Furthermore any or all of the data may be encrypted due to classification or information protection requirements. The data is typically assembled on the ground as post-processed files with IRIG time information and various data channels. Calibration factors are applied on the ground. A successful approach must meet certain criteria. 1) Low Computational Overhead: on-board processing is typically limited. 2) Readily transportable to different processors. The concept must be able to be adaptable to different flight vehicles and flight computers 3) Lossless compression. While the standards of this will vary depending on the data stream in question for some values, including imagery, it may be critical to completely and rigorously reconstruct the precise radiometric scene. This would be on an item by item basis but lossless compression must be available as an option for any stream. 4) Low latency. While some computational delay is expected the telemetry data in the moments in advance of a failure, intercept, anomaly or other instantaneous event are often of the highest interest. As a result, latencies on the order .01 seconds are desired. 5) Overall telemetered data footprint reduction on the order of 5x or greater but smaller compression amounts are to be expected for different data types and techniques which meet all criteria but achieve lower overall compression are still of interest. 6) Robustness under compression. Typically data is compressed before encryption but this can reduce the security level of the telemetered data due to predicable patterns put into the compressed data which can make cryptanalysis easier. Since it may be possible to protect any specific details of implemented algorithms as classified, high consideration will be given for specialized models which can maintain performance and security of national security information. 7) Simplicity is a goal. Since algorithms are generally tailored for specific types of data, a multi-algorithm approach is useful but a successful solution will cover all types of expected data and will contain the simplest implementation as possible. For the tasks in all Phases of development, telemetry streams at the appropriate classification level and reflecting the program needs and requirements will be provided to all awardees as Government Furnished Information (GFI). Performance will be judged based on compression amounts, data loss/degradation and computational efficiency as criteria for progress from Phase I to Phase II or Phase II to follow-on work. PHASE I: Demonstrate the feasibility of the proposed approach on the GFI data sets. Provide statistics on compress ratio, computation time/latency, processor compatibility, and applicability to the different data streams and types. Imagery data in particular can be extremely challenging for downlinking, successful proposals will include some treatment of this type of data. While classified data will not be supplied, Phase 1 work should also address the potential for dealing with encrypted data and a projection of expected performance. PHASE II: In Phase II representative encrypted data will be provided GFI along with a complete data stream for processing and scoring. Once demonstrated for these classes of data the contractor will provide a post-flight a postiori data compression using hardware in the government Tech Team laboratory which will be reduced by the government as would flight TM and compared to the results obtained on mission day. After this a fully or partially encrypted data will be tested in the same facility and used for final evaluation. Additional interchanges with prime target providers will be held. Phase II software interfaces for integration into target provider launch vehicles will be identified and fully documented in the Phase II final report. PHASE III: Phase III will involve the successful integration and implementation of the compression software (or hardware/software solution) in live flight (real time) conditions in a piggy-back mode. Results will be compared to ground test results and to official truth data products. This will require a teaming arrangement and a path for tech transfer into industry directly at the end of Phase III. Either a follow-on test will run on board in real time for a flight test using fully or partially encrypted data or depending on logistics the initial real time test will be conducted for encrypted data streams COMMERCIALIZATION: The contractor will pursue commercialization of the various technologies developed in Phase II for potential commercial uses in such diverse fields as methodology and tool development for DoD. The commercialization for MDA Targets may come from teaming arrangements reached between the algorithm provider and target prime contractors. In addition, it is expected that if successful for encrypted data there will be substantial other applications within the DoD in MDA, Space Surveillance and other organizations.
US Flag An Official Website of the United States Government