Analog Sliding Window Decoder Core for Mixed Signal Turbo Decoder

The application of turbo codes in modern communication systems makes decoding a time and power consuming task. It is known that analog decoder are superior to digital decoder designs in terms of speed and power consumption. The fact that a modification of a single code parameter like the block length requires a new analog decoder implementation, in combination with a complexity, which grows linearly with the block length, so far prohibits a real world application in e.g. UMTS. This paper introduces a novel mixed signal turbo decoder for different block lengths and arbitrary interleaver structures. For the prominent case of the UMTS turbo code the complexity of the component decoder is reduced by a factor of up to 91 compared to an all analog implementation with a performance loss of only 0.05 dB.

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