Margin Propagation and Forward Decoding in Analog Vlsi

We propose margin propagation as an alternative to probability propagation in forward decoding. In contrast to sumproduct probability propagation, margin propagation only incurs addition and subtraction in the computation and thus leads to reduced complexity of implementation. Simulations indicate that margin based forward decoding is more robust to input noise and parameter mismatch than sumproduct probability decoding, and offers superior decoding performance. We also present an analog VLSI implementation of the margin propagation network independent of MOS device models, and provide experimental results from a prototype fabricated in a process.