Chinese 3g-------TD-SCDMA

China is targeting to have a 3g network up and running before 2008 Olympics and is soon going to award a 3G license to one carrier for deploying its own version of 3g technology ----TD-SCDMA. In order to keep competing technologies---- CDMA-2000 and W-CDMA and their latest versions at bay, it is not going to award any other licenses for a least two years. For course this is one of the many statements China has made to announce it's arrival as a super power but this technology does deserve to see the day of light on the technological merits.

The Time Division Duplexing (TDD) scheme is at the heart of TD-SCDMA standard and ‘ Synchronous” denotes that is can handle both circuit –switched and asynchronous data packet switched services. TD-SCDMA offers a smooth and seamless way of upgrading existing GSM networks for advanced 3G mobile networks and services. When TD-SCDMA base stations are installed in an existing GSM system, the radio network layout can be retained and existing transmission links can be reused. TD-SCDMA provides spectrum efficiency 3 to 5 times greater than GSM. Together with the added ability to handle symmetric and asymmetric services as well as flexible data rates - each carrier can be used with maximum efficiency.
Time Division Multiple Access (TDMA) in combination with Time Division Duplex (TDD) significantly improves network performance by allowing radio resources to process network traffic in both directions, per uplink and downlink. TDMA uses a 5 ms frame for repetitive transmissions. This frame is subdivided into 7 time slots, which can be flexibly assigned to either several users or to a single user who may require multiple time slots. TDD principles permit traffic to be uplinked (from the mobile terminal to the base station) and downlinked (from the base station to the mobile terminal) using the same frame and different time slots. For asymmetric services used with Internet access, where high data volumes are transmitted from the base station to the terminal, more time slots are used for the downlink than the uplink.

I know most of us are transparent to technology behind and it does not matter as long as we are able to call and remain connected but for some of us who have already tried their hand on CDMA-2000 and W-CDMA, it is a fascinating new world .