US : Cellular3G Inc., the wireless chip-set company with a R&D site in the UK, stepped up its UMTS offering with a full rate HSDPA solution, a natural migration from its, already commercial UMTS Rel.4 UE baseband processor implementation, TopHat(TM).

"We invite cellular telephone manufacturers and chip makers to join our satisfied clientele. Come meet and discuss licensing or your custom built requirements", said Menachem Kenan, CEO of Cellular3G.

Alex Lax, CTO adds "The design meets the requirements of the 3GPP FDD standard Releases 3 and 4, and work is well advanced on meeting the further requirements of Releases 5 and 6 with a working FPGA. Release 5 will be available in mid-2005. At 384Kbits/sec, TopHat(TM) would consume no more than 75mwatts when implemented using a 0.13 micron process and requires no more than 22mm2. "

Cellular3G is looking for semiconductor companies and cellular telephone terminal manufacturers wishing either to license the design, or to order custom made UMTS UE baseband chips compliant with Releases 99, 4, 5 and 6. The company is also looking for protocol stack and application platforms partners to collaborate on its HSDPA solution.

TopHat(TM) achieves the maximum data rate specified in the 3GPP standard (2Mbps each way) with very low power consumption by using configurable processor engines, thereby reducing the clock rate required for all the required computations and minimising the area of silicon which is in use at any one time. The clock speed has been limited to 30.72MHz (8 times the chip rate) and the transfers of data around the system and data paths have been minimised.

Cutting down the amount of data transfers was achieved by developing special processors designed to operate with data resident in a small area of the chip. On the Receive side Cellular3G developed a 'Pico Processor' dedicated to the analysing and processing of the RF channel characteristics for the RAKE receiver. The Pico Processor, while being controlled by TopHat(TM)'s ARM core, continues to process data using its own software.

The chip does not require a DSP. It utilises an ARM9 for configuration and control, but the ARM core is only involved in a small proportion of the data processing and, generally, none of the transmitted data would be passed through the core.

TopHat(TM)'s architecture is designed for an easy integration with an embedded DSP. This DSP can take over most of the GSM/GPRS functions and when the chip is in UMTS mode, the DSP can concentrate exclusively on 3G applications processing.