Radio jamming in China
Radio jamming in China is a form of censorship in the People's Republic of China that involves deliberate attempts by state or Communist Party organs to interfere with radio broadcasts. In most instances, radio jamming targets foreign broadcasters, including Voice of America (VOA), Radio Free Asia, the BBC World Service, Sound of Hope (SOH) and stations based in Taiwan. Methods. Radio jamming is achieved by transmitting radio signals on the same frequency as the intended target. The government of the People's Republic of China disrupts shortwave radio communications through this method, typically by broadcasting  music, drumming, or other noise. On shortwave, the jamming sound is usually composed of Chinese folk music, specifically a composition known as "The Firedrake", running one hour in duration (sometimes a relay of CNR 1 is used instead). The one hour audio clip is broadcast at high power from the ChinaSat 6B satellite (launched in 2007) on the same frequencies used by target stations. High quality recordings of "The Firedrake" also exist on the internet. On some occasions, China National Radio broadcasts are also used to jam target signals. The French defense electronics company Thales Group was accused of aiding  Chinese censorship efforts by selling shortwave broadcasting equipment to Chinese authorities in 2008. The firm responded saying that the sale of equipment was for civil purposes. Targets. Voice of America and Radio Free Asia. Since broadcasting began in 1996, Chinese authorities have consistently jammed Radio Free Asia broadcasts. In 2002, the Broadcasting Board of Governors reported that "virtually all of VOA's and RFA's shortwave radio transmissions directed to China [...] are jammed," including their Mandarin, Cantonese, Tibetan, and Uyghur language services. Voice of Tibet. In 2008, the Oslo-based Voice of Tibet reported that jamming of its radio communications  intensified during the 2008 Tibetan unrest, as authorities increased the number of disrupted signals it employed to block outside transmissions. Others. Other targets for jamming include the BBC World Service, Radio Taiwan International, and the Falun Gong-affiliated Sound of Hope radio network. Response. In 2011, some international radio broadcasters, including both the BBC and VOA, announced plans to scale down or close their Mandarin shortwave service for China due to spending cuts and frustrations caused by jamming efforts. BBC and VOA instead chose to invest more heavily in internet radio; both received financial support from the U.S. Department of  State to fund and research internet censorship-circumvention software, such as Freegate and Ultrasurf, to enable their Chinese audience to access their programs online. Broadcasters have also sought to educate their audiences on the use of anti-jamming technology.