A comma-free Reed-Solomon decoder chip for W-CDMA/FDD applications

A (15, 3) CFRS (comma-free Reed-Solomon) code has been devised in the 3GPP W-CDMA/FDD system (3^rd generation partnership project, wideband code division multiple access/frequency division duplexing) in order to facilitate frame synchronization and code-group identification in the cell search procedure. This paper proposes a CFRS decoder chip for fast, multi-speed decoding in this application. With this fast decoder, realization of more sophisticated cell search algorithms that may be needed in some application scenarios will become feasible. Besides, a multi-speed decoding can be implemented within the same architecture. Multi-speed decoding equips a mobile for being able to use different algorithms in different cell search scenarios. The decoder achieves low power dissipation with low clock rate as well as fast decoding for a cordless mobile by using a folding systolic architecture. Finally, the proposed CFRS decoder is realized in a 3.3-V 0.35-μm CMOS technology with 2.2×2.2-mm² core area and 13.3/1.23-mW power dissipation.