SAN JOSE, California

Sandbridge Technologies Inc., a designer of cellular baseband chips, has been acquired by China's Wuxi DSP Technologies, according to Will Strauss, president of Forward Concepts, in a newsletter.

''The original Sandbridge office in the U.S. has become the company's R&D center, called Optimum Semiconductor Technologies,'' according to Strauss.

Last year, Strauss said Qualcomm bought 4G modem chip company Sandbridge.

''My guess is that Qualcomm bought patents and the staff went to the Chinese'' company Wuxi DSP,'' he said in an e-mail.

Sandbridge's ''SB3500 chip features the Sandblaster DSP for execution of baseband operations in software, including the physical layer. It has a programmable RF interface, with the capability to capture raw data at 240 M samples/sec. It includes interfaces to LCD, keypad, USIM, SmartCard, Audio codec, IrDA, plus emerging 'critical' features such as add-on memory cards, camera interface, and USB,'' according to Strauss.