LS Cable Ltd, South Korea's largest cable maker, aims to increase sales in China from US$150 million this year to US$1 billion, the China Daily reported.   Lee Kwang-won, President of LS Cable China, said LS Cable's sales in China would reach US$150 million in 2006, after doubling every year for the past two years.   The targets are US$650 million in 2008 and US$1 billion in 2010, wrote the paper.   The biggest South Korean cable maker, with a share of about 40 per cent of its home market, has been looking to extend its leadership in other markets, with China as a base.   The company has recently invested US$10 million into a new air conditioning factory in Qingdao in East China's Shandong Province., the second factory following the one located in Pingdu.