Korean handset manufacturer Samsung launched what it claims to be the first multi-mode mobile phone combing HSDPA with China’s homegrown 3G technology TD-SCDMA.

The SGH-T578H phone is based on the T3G7210 system, which features an implementation of one of the industry’s earliest soft modems and was built in conjunction with NXP Semiconductors and T3G Technologies.

TD-SCDMA network deployments have been completed in ten major cities across China, where there are more than 70 million potential subscribers.

The technology network is planned to be upgraded to support Release 5 (HSDPA) of the TD-SCDMA standard during 2008, ahead of the Beijing Olympics, so operators can deliver rich content at high speeds.

Over the summer, Chinese TD-SCDMA developer, T3G Technology, said that it had completed the world’s first voice automatic handover of multi-mode TD-SCDMA and GSM/GPRS/EDGE in a handset.

The news marked yet another milestone in the maturity of the Chinese homegrown 3G technology, and will likely fuel more speculation on the licensing of 3G spectrum in the country.

The development means that users can experience seamless bi-directional and on the fly automatic handover between TD-SCDMA and GSM networks.

Multi-mode 3G devices will be able to automatically scan for available networks and smoothly switch between TD-SCDMA and GSM/GPRS/EDGE networks.