Baseband Processing for 3G Base Stations: DSPs vs. FPGAs:
eetimes.com
The high processing requirements of 3G systems result partly from the 2-Mbit/second data rates, as per the UMTS W-CDMA standard. More important, however, is the CDMA coding technique, which requires high-speed, chip-rate processing to perform the pseudorandom-number generation, channel spreading, mux/demux, rake receiver and symbol-combining functions.
Speaking at last week's Communications Design Conference here, Asif Batada, manager of wireless marketing strategy at Altera, put the processing requirements in perspective.
"To date, phones based on GSM or IS-136 [the North American TDMA standard] have required 100 and 200 Mips of processing power [respectively]," Batada said. "As we move to 3G and also start to incorporate advanced features such as multiuser detection, that jumps to 5,000 Mips — a 50x jump. There's no way a general-purpose DSP can handle that sort of chip-rate processing for multiple channels." |
