This Chinese article published in the PRC open journal Modern Defense Technology [ 现代防御技术], evaluates U.S. progress in developing next generation early warning satellites illustrates open source collection, provides an overview of military space high tech field and gives some indication of what PRC defense scholars may be thinking.
Reading through the reference is interesting. The third reference is an evaluation of Russian satellite early warning systems; unfortunately that one isn’t online! Sources include U.S. aerospace company announcements of contracts, articles by other PRC scholars on U.S. military space systems, a student paper from the U.S. Navy Postgraduate School in Monterey, Gunter Kreb’s remarkable Gunther’s Space Page, and a U.S. Air Force soliciation for sensor algorithm development.
Study the footnotes and endnotes of a book or article can be enlightening. I remember twenty-some years ago when I read the PRC book Unrestricted Warfare by two PRC writer-senior colonels (the PLA has some interesting specialties, even (until a few years ago) generals whose military occupational speciality was singing, Chinese Communist Party General Secretary Xi Jinping’s wife Peng Liyuan had the rank equivalent of major general in the PLA Arts Troupe.). The book discussed many kinds of unconventional warfare and stirred up considerable attention and even worry on the part of some people in Washington. I went through the book thoroughly and end up doing a four-part summary translation which I drafted and were sent back from Embassy Beijing where I worked in the Environment, Science and Technology Section.
My most interesting discovery reading the book cover-to-cover was that about 60% of the footnotes were U.S. Department of Defense publications. This seemed to be multiple mirroring — some Chinese people worry about the US, write a book about that and then some people in the USA read the book and worry “what are the Chinese up to!”. Other countries worry about their defense and the USA worrying about its defense can lead to the other side’s concerns being misinterpreted as offensive intent, intent being so hard to figure out that countries often will focus on potential adversary military capabilities rather than intent. Just because you’re not paranoid doesn’t mean that they aren’t out to get you. On the other hand, the worst assumption can become the default and can move from being thought of as a hedge against the worst case to being thought of as the really real.
At the time were were releasing unclassified versions of some of our U.S. Embassy Beijing reporting cables and putting them on the U.S. Embassy Beijng website (still available on the Internet Archive). The summary translation is also available on the Federation of American Scientists website under Chinese Doctrine/Conventional Forces.
Government Accountability Office Report on Next Generation Missile Warning Development
The September 2021 Government Accountability Office report “MISSILE WARNING SATELLITES:
Comprehensive Cost and Schedule Information Would Enhance Congressional Oversight” cautions on the technical, managerial and cost-containment challenges of the next-generation U.S. missile warning system project.
What GAO Found :The U.S. defense and intelligence communities depend on data from overhead
persistent infrared sensors. These sensors provide early warning of ballistic missile launches and contribute to other defense and intelligence missions. The planned Next Generation Overhead Persistent Infrared (Next Gen OPIR) system is intended to replace the Space Based Infrared System, which began in the mid1990s. The Space Force plans to launch the first of five Next Gen OPIR satellites
in 2025. The figure below presents a notional depiction of current and planned
Despite early steps to speed up development, the Next Gen OPIR program faces significant technical and managerial challenges—such as developing a new mission payload and serving as the lead system integrator for the first time in this area—that are likely to delay the initial launch. Significant schedule delays typically result in cost increases. Although officials are aware of schedule risks, they continue to present an on-track timeline and stable cost estimates in reports to congressional committees. More transparency in schedules and costs would contribute to better Department of Defense (DOD) and congressional oversight and decision-making.
The first Next Gen OPIR satellites are intended to provide missile warning capabilities and support other mission partners. DOD has initiated multi-agency efforts to determine how to meet future needs. However, coordination mechanisms are not formalized. Without documenting roles, responsibilities, and
plans, DOD risks ineffective collaboration and unsynchronized delivery of warfighter capabilities.
Modern Defense Technology [ 现代防御技术], 2022, 50(2): 18-25 doi: 10.3969/j.issn.1009-086x.2022.02.003 is a Chinese online defense journal. Article URL: https://www.xdfyjs.cn/article/2022/1009-086X/1009-086X-2022-50-2-18.shtml
From Advice for potential contributors 投稿须知 to Modern Defense Technology:
In order to improve the efficiency of your submission, please read the following requirements carefully.
- Modern Defense Technology only publishes original manuscripts, and rejects multiple submissions and manuscripts involving confidentiality.
- The manuscript must be provided with a certificate of confidentiality review with the official seal of the organization, otherwise it will not be published. The official seal of the confidentiality review certificate should be the official seal of the confidentiality committee or the confidentiality department of the institution or research institute where the first author is located, and the official seal of secondary institutions (faculties, departments) and research laboratories will not be recognized. In case of confidentiality problems, all consequences will be borne by the authors themselves and the editorial office will not be responsible for them.
- This journal mainly publishes domestic and foreign defense technology, including air and space defense system, strategy and tactics, air defense missile weapon system in general (including weapon system in general, missile technology, navigation, guidance and control, command and control and communication, detection and tracking technology, military electronic information system, simulation technology, target characteristics, launch technology, test technology, launch control technology, reliability technology, weapon equipment and combat use, etc.), and scientific and technical papers on precise guidance technology, etc.
- The columns of Modern Defense Technology are as follows: air and space defense systems and weapons; missile technology; navigation, guidance and control; command and control and communication; detection and tracking technology; integrated security technology; test and launch control technology; military electronic information system; simulation technology. The authors are requested to give their suggestions on which section of the article is suitable for publication in the following and write them on the top left corner of the first page of the article.
- The article is required to have clear arguments, reliable data, clear organization, concise text, and initially meet the requirements for publication.
Research paper: A complete discussion of a major or important scientific or engineering research result in the field of defense technology that is innovative and groundbreaking and that contributes to the development of the academic field.
Review: To review and comment on the latest research results in the frontier issues, interdisciplinary and high technology innovation in defense technology research, discuss the remaining problems, and propose ideas for future development.
In the translation I have added some links to article that may help undertand the technologies being discussed.
Jiu-Long Wang, Xiao-Yi Wang, Hai-Fei Hu, Sheng Cai
Changchun Institute of Optics and Precision Mechanics and Physics, Chinese Academy of Sciences, Changchun 130033, Jilin, China
Research Progress of the US “Next Generation Overhead Persistent Infrared” (OPIR) Early Warning Satellite
WANG Jiu-long, WANG Xiao-yi, HU Hai-fei, CAI Sheng
Chinese Academy of Sciences, Changchun Institute of Optics, Fine Mechanics and Physics, Jiling Changchun 130033, China
The U.S. space-based early warning satellite system is an important component of the missile defense system, and the study of its development status and capability is of great significance. In order to support the basic research and engineering development of China’s space-based optical early warning related fields, the development history, system composition and main problems of the U.S. defense support program (DSP) and space-based infrared system (SBIRS) two generations of space-based early warning satellites are analyzed. On the basis of the research progress and achievements of the U.S. “overhead persistent infrared” (OPIR) early warning satellites, a detailed summary of their research progress in the areas of constellation planning, sensor payload development, ground data processing system and data standard specification is presented. The research progress and achievements of OPIR satellites are summarized in detail.
Keywords: early warning satellite ; space-based infrared system ; overhead continuous infrared ; sensor payload ; ground-based system ; data standard
doi:10.3969/j.issn.1009-086x.2022.02.003 . Chinese library classification number：V474. 2；TJ01 Document Classification code：A Document serial number：1009-086X（2022)-02 -0018-08
Abstract [in English in the original text]
The U.S. space-based early warning satellite system is an important part of the missile defense system, and the research on its development status and capabilities is of great significance. The U.S. space-based early warning satellite system is an important part of the missile defense system, and the research on its development status and capabilities is of great significance. In order to support China’s fundamental research and engineering development on space-based optical early warning, the research progress and achievements of the US “next generation overhead persistent infrared” (OPIR) early warning satellite are reviewed based on the analysis of the development history, system composition and main issues of the two generations of space-based early warning satellites of the US defense support program (DSP) and space-based infrared system (SBIRS). The research status of constellation planning, sensor payloads development, ground data processing system, OPIR data standardization is summarized in detail. It is suggested that the research should focus on building the target infrared image data set, developing wide-field of view (WFOV) data processing algorithms, developing search and tracking It is suggested that the research should focus on building the target infrared image data set, developing wide-field of view (WFOV) data processing algorithms, developing search and tracking integrated large area array payload technology, strengthening satellite near-field The first step is to develop an integrated search and tracking large area array payload technology, strengthening satellite near-field perception and defense.
Keywords: early warning satellite ; space-based infrared system ; overhead persistent infrared ; sensor payloads ; ground system ; data standard
[Chinese text continues]
Research progress on the next generation of U.S. Overhead Continuous Infrared (OPIR) early warning satellite
By WANG Jiulong, WANG Xiaoyi, HU Haifei, CAI Sheng:
Modern Defense Technology[J], 2022, 50(2): 18-25 doi:10.3969/j.issn.1009-086x.2022.02.003
WANG Jiu-long. research progress of the US “Next Generation Overhead Persistent Infrared” (OPIR) Early Warning Satellite. modERN DEFENSE TECHNOLOGY[ J], 2022, 50(2): 18-25 doi:10.3969/j.issn.1009-086x.2022.02.003
Space-based early warning platforms consisting of geostationary, large elliptical high-orbit, and low-orbit satellites as well as composed of space-based early warning platforms represent a new generation of early warning technology which the United States, Russia, and China are competing to develop because of their theoretical ability provide global coverage for target detection. [1-3]. Early warning satellites play an important role in strategic defense systems since they provide important means for surveillance, detection, discovery and tracking of enemy strategic missiles . The development of the U.S. early warning satellite system began in the 1950s to detect Soviet ballistic missile launches. The United States developed and deployed the defense support program (DSP) early warning satellite  – the first generation of U.S. space-based early warning satellites to be deployed in geosynchronous orbit. By 2007, DSP satellites have undergone five development phases, with 23 satellites launched and two still in service in orbit.The main shortcoming of DSP include: ① inability to track mid-flight missiles; ② the dependence of satellite data processing on foreign stations; ③ its low scan rate, low frequency band and high false alarm rate of infrared detectors on board; ④ its slow scan speed results in an inability to effectively warn of missiles in war zones; ⑤ detector sensitivity and resolution are low; ⑥ DSP lacks a staring camera, which could track the ballistic missile target with high accuracy. To overcome DSP inadequacies, the United States in 1992 began the development of the space-based infrared system (Space-Based InfraRed System, SBIRS) . SBIRS system problems include: (1) system resilience and anti-destruction capability is insufficient, it lacks the ability to defend itself against a variety of hard and soft kill means; (2) it cannot adapt to the development of new air and space threat targets and can not meet the needs of future missile defense operations; (3) SBIRS is expensive, time-consuming to build; (4) the technology of “line scan + tracking with phased array antenna that are too small” [Translator’s note: for comparison, see specifications for ground-based phased antenna array for missile tracking.] cannot effectively adapt to the realization of multi-domain multi-target early warning tracking.
To target future space operations in response to emerging and anticipated threats, the U.S. Air Force proposed the “Next-Generation Overhead Persistent Infrared” (NG-OPIR) early warning satellite program, through “using a mature satellite platform + focus on sensor technology” to effectively reduce the operational target value of missile warning satellites and thus obtain a higher probability of survival . Moreover, “relatively simple and inexpensive” early warning satellites can be manufactured in large numbers and rapidly deployed in wartime to complement and sustain space-based missile warning capabilities and enhance the system resilience of missile early warning satellites.
1 Overview of OPIR
1.1 Constellation Composition
The U.S. Air Force launched the Next Generation Overhead sustained InfraRed (OPIR) early warning satellite program in 2018, which is a new generation of high-orbiting early warning satellite system planned by the U.S. after DSP and SBIRS, jointly operated by the U.S. intelligence agencies and the Department of Defense. OPIR consists of space-based sensors and ground-based data processing stations that work in a cooperative network to continuously or nearly continuously collect visible, near-infrared, short-wave infrared, and mid-wave infrared energy from space and process it to produce infrared images that support missile warning , missile defense, technical intelligence, and battlefield space awareness, among other domain missions .
The FY 2019 budget proposal calls for the cancellation of the SBIRS-GEO7 and GEO8 development programs and the dedication of related funds to the construction of the OPIR constellation, which is planned to have five satellites, three in geosynchronous orbit and two in polar orbit, as shown in Table 1.
Table 1 Composition of OPIR constellation
Satellite number Year Orbit
- OPIR-GEO 1 (NGG 1) 2025 Geosynchronous orbit (GEO)
- OPIR-GEO 2 (NGG 2) 202x Geosynchronous orbit (GEO)
- OPIR-GEO 3 (NGG 3) 20xx Geosynchronous Orbit (GEO)
- OPIR-Polar 4 (NGP 4) 2027 High Elliptical Orbit (HEO)
- OPIR-Polar 5 (NGP 5) 20xx High Elliptical Orbit (HEO)
1.2 Research and Development Program
In 2018 the U.S. Air Force selected Lockheed Martin and Northrop Grumman as the prime contractors for the OPIR program . Among them, Lockheed Martin was awarded a sole-source contract of more than $3 billion for the development and production of three GEO satellites, with the first satellite expected to be launched in 2025; Northrop Grumman was awarded a $2.3 billion contract for the development and production of two HEO satellites, with the first satellite expected to be launched in 2027. five satellites will be completed in 2029 to complement the active SBIRS The OPIR early warning system consists of HEO satellites, polar-orbiting satellites, and ground-based systems, as shown in Figure 1.
Fig. 1 Schematic diagram of Flexible OPIR Ground Architecture
[in orange] EGS/FORGE/S2E2 All-weather/continuous/monitoring
[violet upward pointing arrow] Joint Space Combat Center, National Space Defense Center
In the Block-1 phase of OPIR, the U.S. is actively seeking to build a new system based on innovative technologies, aiming to enhance the system’s destructive capability and strive to complete the deployment of operational satellites by 2030. Once OPIR is deployed and operational (as shown in Figure 2), it will directly support anti-missile warfare at the strategic and tactical levels, and will have a significant impact on “missile-centric warfare.
Fig.2 OPIR complete system architecture
2 Payload development
2.1 Overall Progress
OPIR uses a very large surface array multi-band infrared array focal plane detector that can detect and track not only large ballistic missile launches, but also small surface-to-air missiles, boosted glide and aspirated hypersonic weapons, and even air-to-air missile launches. The U.S. Air Force has asked Lockheed Martin and Northrop Grumman to competitively develop a next-generation OPIR satellite sensor payload to mitigate the schedule issues facing the first launch of a GEO satellite in 2025. Payload development for the NGG satellites in Block 0 phase was contracted to 2 companies, Raytheon Intelligence & Space and Northrop Grumman-Ball Aerospace , to design, build, assemble, integrate, and deliver one mission payload each for the first two GEO early warning satellites. As of May 2020, the two candidate payloads have completed preliminary design reviews and met Air Force metrics requirements, with development expected to be completed in 2023. in May 2021, the U.S. Space and Missile Systems Center (SMC) and Raytheon with [Boeing] Millennium Space Systems) contracted for a digital model of the Missile Tracking Hosted Prototype (MTCP) design, enabling the government to automate the integration and linking of multiple contractors’ models in a digital environment so that the digital model can be used to test whether the sensor payload design meets missile warning requirements before building the next generation of OPIR warning satellites .
2.2 The WFOV project
To secure the OPIR early warning satellite constellation, the Space and Missile Systems Center initiated the development of the WFOV (wide-field of view)  satellite. WFOV is only a test satellite, not part of the missile early warning satellite constellation, and its main mission is to evaluate the technical status of the OPIR wide-field 6° gaze sensor for Air Force Space Command to reduce the next generation missile warning satellite development risk. The sensor payload, developed by L3 Harris (L3 Harris technologies) under a separate contract and mounted on a satellite bus provided by Millennium Space Systems, has a WFOV system that weighs approximately 1,000 kg, about one-quarter the size of the SBIRS satellite, and was originally planned for launch into geosynchronous orbit in 2021 via the U.S. Air Force USSF-12 mission, but according to latest information, the Atlas-5 launch vehicle for the USSF-12 mission will be launched in the 1st quarter of 2022.
2.3 SBIR Project
In 2016, the U.S. Department of Defense released the WFOV mission data processing algorithm development project  on the SBIR website to develop and test a WFOV mission data processing algorithm for “next-generation overhead sustained infrared” to process large-format 4 k × 4 k data from GEO orbit at frame rates below 10 Hz in real time. The project is being implemented in three phases: Phase 1 completes the prototype algorithm design with algorithm tiling and windowing, noise suppression, jitter suppression, spurious suppression, thresholding and buffering; Phase 2 tests the algorithm based on real-time WFOV data from the payload and changes and adjustments to the algorithm based on the results; and Phase 3 completes the algorithm certification in 2021 and converts it to the WFOV mission control system. In the meantime, the first commercial payload for over-the-top sustained IR [15-16] was launched into geosynchronous orbit as early as 2011 with a demonstration to validate the ability to build and integrate large field-of-view sensors based on commercial payloads and to understand the WFOV staring payload IR principle and quantify the WFOV performance level.
3 Ground-based Data Processing System
The SBIRS team and Raytheon have proposed different solutions for the construction of the OPIR ground data processing system.
3.1 SBIRS Team Solution
In order to adapt to the challenges of rapidly changing battlefield spatial situational awareness, in 2016, the SBIRS team proposed a modular, hierarchical, and adaptive OPIR ground application development framework based on open system architecture (OSA)  to support multi-mission, multi-sensor battlefield situational awareness missions.SBIRS team believes that the expanding mission domain of OPIR, the growing demand for OPIR data, and the dynamic nature of the battlefield spatial situational awareness mission are driving significant changes in the ground processing system, and Figure 3 illustrates the missile warning and evolving mission domain supported by OPIR.
Fig. 3 OPIR mission area [captions left to right: Guided Missile Early Warning, Real Time Data Exchange, Battlespace Situation, New Types of Tasks
Under the traditional framework, specific interfaces need to be designed between different components, which are developed, tested and then integrated into the larger system; whereas the OSA framework uses an open, standard unified programming interface, which does not require the development of component-specific interfaces and has portability and tailorability features that can facilitate rapid deployment of new operations. The OSA-based framework not only enhances missile defense and early warning, but also enables rapid response to changes in operational requirements and allows efficient deployment of operational systems for data processing.
3.2 Raytheon Solution
On January 28, 2020, Raytheon was awarded a 5-year, $197 million contract by the U.S. Air Force to design the OPIR ground data processing system, a program known as Future Operationally Resilient Ground Evolution (FORGE) . FORGE is essentially an open architecture that is scalable, extensible, and flexible, allowing for the development of specific applications based on a platform whose primary mission is to issue missile warnings to the Pentagon and national command agencies but it also supports civilian application development, as shown in Figure 4.
Fig. 4 FORGE open task data processing system [100% open, government-owned, four automatic security sweep layers, 100% standard applications program interface (API), 55 enterprise design patterns, 44 free open source (FOSS) packages, FORGE/MDPAF task data processing systems.]
FORGE is divided into 3 parts: command and control, mission data processing, and relay ground station. The prototype system includes unclassified data processing platform, classified data processing platform, and scalability test platform. The U.S. Space and Missile Systems Center (SMC) said it will use an “agile approach” to develop the FORGE ground system, tracking progress in an iterative, step-by-step manner that allows for adjustments and treatment of mission issues that arise during development, reducing the risk of project failure and ensuring that FORGE becomes the best solution for future and next-generation SMC is using two open framework architectures to improve DoD’s OPIR data processing: the system architecture and the mission framework. (ii) integrate new capabilities quickly and inexpensively; and (iii) support the changing needs of the warfighter and ensure continuity of operations. Figure 5 shows the FORGE prototype system architecture.
Fig. 5 FORGE prototype system architecture
4 Data standard specification
To develop a standard specification for early warning satellite data, the U.S. Strategic Command, the Joint Force Space Component Commander, and the National Geospatial-Intelligence Agency jointly established the Overhead Sustained Infrared Specialty Group to develop an open OPIR data standard  to support missile warning, missile defense, operational environment awareness, technical intelligence, and civil/environmental missions. OPIR data processing levels are divided into five levels, with level 0 representing raw sensor data and level 5 representing technical intelligence products. Of these, level 3 data (Figure 6) indicates that raw OPIR data is partially processed but is not a final intelligence product or a re-useable product. The Level 3 data typical return value (rep return) contains conceptual data model, logical data model, and associated data dictionary definitions. The logical data model has a number of entities that describe the OPIR platform and sensor attributes, including field of view, axis of view, and data collected and processed from the sensor. The data dictionary describes the attributes and units of values contained in each entity.
Fig. 6 OPIR conceptual data model
Figure 6 depicts the conceptual model of OPIR Level 3 data, and Figure 7 depicts the logical model of OPIR Level 3 data, including entities, attributes, and relationships, for a complete description of the standard specification of typical return values, which is being extended to support Level 1 and Level 4 data, called the federated OPIR data model.
Fig.7 OPIR logical data model
5 Summary and Recommendations
The U.S. Next Generation Overhead Continuous Infrared (NGOIR) early warning satellite enhances high-orbit infrared detection capabilities, extending missile warning to a full range of “from start to finish” detection, tracking, and assessment of threat such as missiles, and hypersonic weapons. This enables rapid response to new threats emerging around the world. The mission is to detect, track, and assess threats from life to death, including missiles and hypersonic weapons. Orbit from the initial geostationary orbit to the combination of large elliptical orbit to the direction of high and low orbit network cooperation; detection method also from a single “line array scan” to “scanning + staring” and the future “multi-faceted phased array staring” direction; development method also from the initial high cost, long development cycle of a single large satellite way to low-cost, modular development of small satellite way development.
For the future development and planning of China’s missile early warning satellite, first of all, we must build a flexible and decentralized space architecture, using a combination of high and low orbit deployment, in geostationary and high earth orbit deployment of large satellites, in low earth orbit make full use of commercial satellite development results, build a large-scale, low-cost small satellite constellation; secondly, focus on the development of search and tracking integrated large surface array payload technology. We need to research wide field of view mission data high-performance processing algorithms, build high-quality, scalable target infrared image data sets, improve the timeliness of satellite onboard data processing under hostile conditions, to achieve discovery and tracking, and to deal with new threats. Finally, in order to enhance the wartime survivability of high-orbit early warning satellites, we should actively develop satellite near-field sensing and maneuver evasion and other defense technologies. In short, the construction of early warning systems should focus on specific needs, and strive to build a space-based early warning system that takes into account strategic and tactical requirements, with tactical applications as the main focus.
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