This paper presents a new pipelined architecture of Turbo decoder which runs at nearly four times the speed of a recently reported architecture with a reasonable increase in hardware. The proposed architecture is based on block-interleaved pipelining technique which enables the pipelining of the add-compare-select-offset (ACSO) kernels. Moreover next iteration initialization (NII) method has been adapted in the proposed work to initialize sliding window border values. The decoder chip consumes 219.8 mW of power at a maximum operating frequency of 192.3 MHz when implemented using 0.18 μm CMOS technology. Synthesis results indicate that the designed turbo decoder can achieve a decoding throughput of 38.46 Mb/s with an energy efficiency of 1.14 nJ/ bit/ iteration at the maximum operating frequency. The proposed architecture is therefore considered suitable for a real time wireless application such as video-telephony in mobile networks.

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Iterative turbo decoder high speed architecture sliding window block interleaved pipelining pipelined ACSO