China's perspectives on 3G mobile communications and beyond: TD-SCDMA technology

China, as the largest developing country in the world, has been emerging as a nation with the fastest penetration rate growth in mobile communications, exceeding the United States to become the largest single mobile cellular market in terms of subscriber population. The recent successful admission to the World Trade Organization (WTO) has given China new momentum for further development of its mobile communications infrastructure and fueled international competition as well in the mobile communication market of the country. Since the opening up of its economy, China has spent billions of dollars to purchase equipment from foreign telecommunication manufacturers, which has created a heavy burden to modernize its legacy industrial sectors. This is the situation China is eager to change. The TD-SCDMA standard was proposed by the CWTS of China to ITU in 1998 as an effort to bring China on a par with other developed countries in mobile communications system development and also to make the country less dependent on foreign vendors. The proposal was approved by ITU as one of the candidate standards for 3G mobile communications in May 2000 and accepted by 3GPP in March 2001. The TD-SCDMA standard makes use of TDD synchronous CDMA technology and offers several operational advantages. For instance, it allows the existing GSM core networks to be upgraded to the TD-SCDMA platform along a relatively easy path. Therefore, it can be very attractive to service providers in regions where worldwide popular GSM system is in operation. The TD-SCDMA standard has received the full blessing of the Chinese government and will surely play a critical role in mobile communications development in China as well as in the world; its impact should never be underestimated. In this survey article the historical background as well as the technical content of the TD-SCDMA standard will be addressed.