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时间:2011-08-22 17:33来源:蓝天飞行翻译 作者:航空
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In sum, China’s military satellite capabilities today are substantial and growing. China possesses at least 10 imagery reconnaissance satel-lites and possibly six or more electronic-intelligence satellites. Informa-tion in unclassified sources indicates that these numbers are similar to the numbers of comparable satellites the United States possesses. How-ever, the capabilities of China’s satellites undoubtedly fall well short of those of the United States. For example, China’s best optical satellites are estimated to have resolution of about 0.8 m. By comparison, com-mercial satellite imagery with resolution of 0.41 m is now available, and U.S. intelligence satellites are believed to have even better resolu-tion (Matthews, 2008). Nevertheless, the capabilities of China’s satel-lites are probably sufficient for most military purposes. As noted above, 0.8-m resolution is more than sufficient to detect and identify by type ships, aircraft, and ground vehicles. Greater degrees of resolution are primarily of utility for intelligence-collection purposes, such as mea-suring the exact dimensions of a missile. Most militaries are more open and transparent than the Chinese military is (or the Soviet military was), however, and much of this type of information is available from open sources. Thus, the qualitative inferiority of China’s surveillance and reconnaissance satellites may not significantly impact their mili-tary utility, and China may have alternative means to compensate for their shortcomings as strategic intelligence-collection platforms.
China’s capabilities in communications, PNT, and weather sat-ellites are less robust than those in surveillance and reconnaissance. Moreover, China has experienced setbacks and delays in many of its satellite programs, most prominently the total loss of two out of four high-capacity communications satellites launched so far and the partial loss of a third. China’s weather-satellite program appears to be delayed, and several non-military programs have experienced delays as well.6 As argued above, however, probably none of these shortcomings are cru-cial. China probably needs significantly less satellite-communications capacity than the United States does, can use public GPS signals for PNT purposes, and can augment information collected by its own weather satellites with information collected by the satellites of other countries and made publicly available. Moreover, programs are under way to address many of these shortcomings in the next few years.
China’s commercial space prospects appear to be less promising in the near term. The only buyers of China’s communications satel-lites have been Nigeria and Venezuela, countries that may have chosen
6 A solar space telescope was originally scheduled to be launched in 2008, and the third satel-lite in the Huanjing series was to have been launched in 2009, but as of July 2010, neither had been orbited, and several satellites scheduled to be launched in 2010 appeared to be behind schedule as well. See Bodeen, 2007; “China to Launch 10 Satellites in 2008,” 2008.
 
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