Yaogan

遥感卫星 Yáogǎn Wèixīng
VRSS-1 satellite based on the Jianbing-6 class of Yaogan satellites
Program overview
Country	People's Republic of China
Organization	SAST CAST
Purpose	Reconnaissance
Status	Active
Program history
First flight	26 April 2006
Successes	149
Failures	1
Launch sites	TSLC JSLC XSLC WSLS
Vehicle information
Launch vehicles	Long March 2C Long March 2D Long March 4B Long March 4C Long March 5 Long March 6A Long March 7A

Yaogan (simplified Chinese:遥感卫星;traditional Chinese:遙感衞星;pinyin:Yáogǎn Wèixīng;lit. 'Remote Sensing Satellite') is the designation used by thePeople's Republic of China to refer to itsmilitaryreconnaissance satellites.^[1][2] Yaogan satellites are largely known to primarily support thePeople's Liberation Army'sStrategic Support Force (PLASSF), formerly the Aerospace Reconnaissance Bureau of theSecond Department of the General Staff.^[3][4][5] The Yaogan program is the successor to theFanhui Shi Weixing (FSW) recoverable reconnaissance satellite program but, unlike its predecessor, includes a variety of classes utilizing various means ofremote sensing such as optical reconnaissance,synthetic-aperture radar (SAR), and electronic intelligence (ELINT) for maritime surveillance. Yaogan satellites have been launched from theTaiyuan Satellite Launch Center (TSLC) inShanxi province, theJiuquan Satellite Launch Center (JSLC) inInner Mongolia,Xichang Satellite Launch Center (XSLC) inSichuan province and theWenchang Space Launch Site (WSLS) inHainan province.^[6]

Although individual Yaogan satellites are often referred to by their number (e.g.Yaogan-18), Chinese militaryreconnaissance satellites are typically categorized by their militaryJianbing designation. Jianbing (尖兵) translates to "point soldier", "vanguard", or "pioneer" and entered use in satellite designations with China's first series of reconnaissance satellites,FSW-0, as the Jianbing-1 series. The first Yaogan satellite, Yaogan 1, is one of three Jianbing-5 (JB-5) series satellites following the finalFSW-3 satellites of the Jianbing-4 (JB-4) series. Because Jianbing designations are secret and only Yaogan numbers are officially used, the Jianbing designations for later classes still remains unknown to the public.

Chinesesynthetic-aperture radar (SAR,Chinese:合成孔径雷达;pinyin:héchéng kǒngjìng léidá) sensor development began in the late 1970s under the Electronic Research Institute of theChinese Academy of Sciences (CAS) resulting in the testing of the first airborneX-band mono-polarization SAR collection in 1981. By 1994, CAS had introduced its first operational, real-time airborne SAR system tomonitor flooding and transmit collected data toground stations.^[7] Preliminary research and development of China's first-generation, space-based SAR system began sometime in the 1980s with development beginning in full in 1991.High-resolution, space-based SAR collection has been ambitiously pursued by thePLA for its potential contributions to all-weathertargeting ofnaval forces in theTaiwan Strait.^[7]

Jianbing-5 series satellites (abbreviated "JB-5") are China's first space-based SAR satellites and the first satellites in the Yaogan program. The development and production of the Jianbing-5 series of satellites have been entirely funded by thePeople's Liberation Army (PLA) as the ability to penetrate the seemingly constant cloud cover present in the southern provinces of Tibet, Sichuan, Yunnan, Guangxi, Guandgong, and Hainan challenges traditional optical collection in those regions.^[8] The PLA also believes that in a potential war SAR collectioncapabilities will be vital to information dominance bymapping terrain, identifyingtargets through cloud cover, rain, fog, and dust, and potentiallymonitoring enemysubmarines in shallow waters or targets insubterranean facilities.^[7] In May 1995, the finalized designs were approved and development began in earnest with the approval of the State Science & Technology Committee (SSTC) andCommission for Science, Technology, and Industry for National Defense (COSTIND).^[7] The CAS Institute of Electronics built the SAR instruments onboard Jianbing-5 satellites, thecraft itself designed by theShanghai Academy of Spaceflight Technology (SAST) which also develops theLong March 4Blaunch vehicle. Other developers involved in the project are theChina Academy of Space Technology (CAST or 5th Space Academy) 501st and 504th Institutes, theChina Electronics Technology Group's (CETC) Nanjing Research Institute of Electronic Technology (known also as the 14th Institute), the Southwest Institute of Electronic Equipment (SWIEE or 29th Institute), and theBeijing University of Aeronautics & Astronautics (BUAA).^[7] SAST is also the developer of theFeng Yun series ofweather satellites.^[7]

Jianbing-5 satellites are built by SAST and launched from theTaiyuan Satellite Launch Center (TSLC) and provide military analystssynthetic-radar imagery purportedly at a spatial resolution as sharp as 5 meters over theL-band (1–2 GHz).^[9] JB-5 satellites have been confirmed to have an electronic motor-poweredsolar panel which can be expanded and contracted by theground control station. Jianbing-5 class satellites have a reported mass of 2,700 kilograms,orbital inclination of approximately 97° inSun-synchronous orbit, and with two operational satellites enjoys a twice daily revisit rate at a 45° viewing angle.^[8][10] Between April 2006 and August 2010, China launched three Jianbing-5 SAR satellites, the last two of which remain in operation from TSLC. Yaogan 1, launched in April 2006, reportedly broke up around 4 February 2010 almost four years after its launch.^[9] Due to the small number of pieces and low orbital speeds, the breakup was likely due to an internal explosion, not a high-speed collision.^[11]

Yaogan 29, launched in November 2015 into a similar orbit, appears to be the modernized successor to the Jianbing-5 series of SAR satellites.^[8]

The Jianbing-7 class of Yaogan satellites, with military designations beginning with "JB-7", are Chinese military radar reconnaissance satellites built by SAST with an orbital period of 97 minutes and a side-lookingradar system designed by the CAS's Institute of Electronics. As of July 2022, China has launched four Jianbing-7 radar satellites with the first launched in April 2009 and the latest in November 2014 with a mass of 1,200 kilograms (2,600 pounds) from TSLC.^[10][12] The third satellite of the Jianbing-7 class, launched in October 2013, had itsorbit lowered from April to July 2020 and consequently underwent an uncontrolleddecay reentering the atmosphere in 2021.^[13]

Although the Jianbing designation is still unknown for latest class of SAR reconnaissance satellites, China has launched three satellites of a modernized successor class to the Jianbing-5 and Jianbing-7 classes ofSARreconnaissance satellites. This class uses the sameorbit as the Jianbing-5 class but likely has a different design according to published illustrations.^[14] The second satellite of this class, Yaogan 33, failed to reachorbit in May 2019. Its likely replacement, Yaogan 33R, was launched a year and a half later but used different launch site (Jiuquan instead of Taiyuan) and into a higherorbit (682 km ×686 km).^[14]

The Jianbing-6 class of Yaogan satellites, with military designations beginning with "JB-6", provides the Chinese militaryoptical imaging capabilities to complement the Jianbing-5 class'sSAR reconnaissance capabilities.^[15] It has been reported that satellites of the Jianbing-6 class have aresolution of 0.8meters.^[9] Jianbing-6 satellites were developed by CAST based on the CAST2000 satellites bus originally developed by the China SpaceSat Company Ltd. Jianbing-6 satellites image the Earth with a spatial resolution of approximately 1.5 meters and transmit them via X-band receiving telemetry, tracking, and command signals over the S-band. As of July 2022, China individually launched six Yaogan satellites of the Jianbing-6 class intolow Earth orbit (LEO) with the first satellite launched in May 2006 and the latest in May 2016.^[10] TheBolivarian Agency for Space Activities signed a US$140 million deal with China Great Wall Industries Co. Ltd. to launch theVenezuelan Remote-Sensing Satellite 1 (VRSS-1) in May 2011 marking China's first export of areconnaissance satellite. VRSS-1 was based on the design of Jianbing-6 satellites and was launched on 29 September 2012 from JSLC.^[10]

The Jianbing-9 class of Yaogan satellites, with military designations beginning with "JB-9" provides the Chinese military with optical imaging capabilities, likely as a successor to the Jianbing-6 class, though it orbits at a much higher altitude of 1,200 km, indicating that satellites of this class are lower-resolution mapping and area surveillance satellites.^[10][16][17] The optical payload of Yaogan satellites in the Jianbing-9 class was developed by theChangchun Institute of Optics, Fine Mechanics, and Physics.^[17][18] China has launched five individual Yaogan satellites of the Jianbing-9 class with the first launched in December 2009 and the latest in August 2015 from TSLC.^[10]

The Jianbing-10 class of Yaogan satellites, with military designations beginning with "JB-10" provides the Chinese military with optical imaging capabilities.^[19] Believed to also be based on the CAST2000 satellite bus, like those of the Jianbing-6 class, three Jianbing-10-class satellites built by CAST and carrying an optical imaging system from the Xian Institute of Optics and Precision Mechanics have been individually launched with the first launched in December 2008 and the reported last of the class in September 2014 from TSLC.^[19][20]

The Jianbing-11 class of Yaogan satellites, with military designations beginning with "JB-11" provides the Chinese military with optical imaging capabilities.^[21] As of May 2022, China has launched two individually launched Yaogan satellites of the Jianbing-11 class with the first launched in May 2012 and the latest in November 2015.^[21]

The Jianbing-12 class of Yaogan satellites, with military designations beginning with "JB-12", are military optical reconnaissance satellites.^[22]

In response toTaiwanese President Lee Teng-hui's visit to the United States in 1995, thePRC initiated theThird Taiwan Strait Crisis conducting high-profilemissile tests,amphibious landing drills, and troop staging inFujian Province, across the strait from theisland of Taiwan.^[23] TheUnited States government responded to the PRC's escalation by deploying the largest Americanshow of force since theVietnam War including sending two Americancarrier battle groups which effectively forced thePRC to deescalate.^{[24][25][26][27]} Since then, thePLA has committed to design and field advancedanti-ship missile systems including theDong Feng 21 and has deployed nearly sixtymaritime surveillance satellites usingelectronic intelligence (ELINT) to locate, identify, and track adversarialvessels to supporttargeting.^[28][29]

The Jianbing-8 class of Yaogan satellites, with military designations beginning with "JB-8", consist of one primary satellite and two sub-satellites launched in triplets. These satellites reportedly perform an ocean or naval surveillance mission similar to those of the United States'Naval Ocean Surveillance System (NOSS orPARCAE) despite the Chinese state-media's insistence they were designed to "conduct electromagneticenvironmental monitoring and related technology tests".^[29][30] The triplet groups likely fly in a loose formation to locateradio emitters using the difference intime of arrival ofradio signals at the different satellites. Jianbing-8 satellites are based on the CAST2000 satellites bus and have amass of 200kilograms (440pounds) and anorbital period of 107.10minutes inLEO.^[9][31][32] As of May 2022, there have been nine launches of Jianbing-8 triplets (twenty-seven total satellites) from JSLC with the first triplet launching in March 2010 and the latest in March 2021.

The CX-5 or Chuangxin-5 (simplified Chinese:创新;traditional Chinese:創新;pinyin:Chuàngxīn;lit. 'Innovation') class of satellites, the only known Yaogan satellites to have been launched atXichang SLC, are still largely shrouded in secrecy and their purpose is only speculated to be ELINT by nature of their triplet launches, similar to satellites of the Jianbing-8 class.

• USSR / Russia -Kosmos (satellite)
• United States -NOSS
• France -CERES (satellite)

• Reconnaissance satellites
• Earth observation satellites of China
• Synthetic aperture radar satellites
• Spacecraft launched by Long March rockets
• Satellite series
• Military equipment introduced in the 2000s
• Satellites of China

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