In this paper, a 64-state four-bit soft-decision Viterbi decoder with power saving mechanism for high speed wireless local area network applications is presented. Based on path merging and prediction techniques, a survivor memory unit with hierarchical memory design is proposed to reduce memory access operations. It is found that more than 70% memory access can be reduced by taking advantage of locality. Moreover, a low complexity compare-select-add unit is also presented, leading to save 15% area and 14.3% power dissipation as compared to conventional add-compare-select design. A test chip has been designed and implemented in 0.18-μ standard CMOS process. The test results show that 30 ∼ 40% power dissipation can be reduced, and the power efficiency reaches 0.75 mW per Mb/s at 6 Mb/s and 1.26 mW per Mb/s at 54 Mb/s as specified in IEEE 802.11a.
|Number of pages||9|
|Journal||IEEE Transactions on Circuits and Systems I: Regular Papers|
|State||Published - 1 Jun 2005|
- Path merging
- Path prediction
- Survivor memory
- Viterbi decoder