The 3G mobile phone is the first to use China's TD-SCDMA (time division-synchronous CDMA) standard. It was developed using local patents, marking another step towards China's goal of commercially using the China-developed data standard.
The developers plan to work with China mobile-phone producers and operators on the commercial release of the TD-SCDMA phone, reported official China news agency, Xinhua. The development project was sponsored by the Chongqing Institute of Posts and Telecommunications.
There is already an experimental network already in operation in Jiangbei District, Chongqing, southwest China, set up by Datang, a local telecommunications corporation. Other backers of China's TD-SCDMA are the local Huawei telecom-equipment firm and German manufacturer Siemens.
3G phones are seen by China's telecoms industry as the future for mobile telecommunications, offering a wider range of services to users.
China's domestically developed TD-SCDMA standard was recently approved by the International Telecommunications Union of the United Nations, and is competing with the European standard WCDMA (wideband code division access) and the American CDMA2000 (code division multiple access) standard.
With more than 221 million mobile users, and growth of 4 million new subscribers a month, China is the world's largest cellular market. The push to domestic standards such as TD-SCDMA aims to cut licensing fees for foreign-developed standards, and hopes eventually make China-developed technology popular internationally.
However, industry watchers have expressed doubts about TD-SCDMA's success, given that it loses connection in moving cars and has uneven cell-to-cell handover. Three of China's four mobile and fixed line operators plan to build WCDMA networks, using TD-SCDMA as a supplementary protocol, with the fourth carrier opting for the CDMA2000 protocol, according to analysts Norson Telecom Consulting.
Talkback
TD-SCDMA address the main problem with CDMA - how to cope with congestion.
CDMA has a time to transmitt function with an expotential O - main component of the "apparently insignificant part of the function". The O is a function of simultaneous users and packets about. GSM solved this by rejecting CDMA. (This is the air interface only!).
By introducing TDMA into CDMA, as GSM, you have the possibility to impose "one thing at a time" when the network is overloaded. The roaming problem is strange that they have not solved - and they may take the GSM sollution.
WCDMA will have this problem.
WLAN has this problem
CDMA2000 has this problem.
CDMA has this problem - all behave very poor once imposed with heavy load - just as the (queue) theory suggested.
DECT/DPRS will provide non-mobile IMT2000 today outside the USA.
It seems like we forget old theory, and ignore old findings - while the Chinese looked at the problem and came up with a diffrent solution - but similar one.