Optimized LDPC codes for partial response channels

We construct codes that can closely approach (and possibly ultimately achieve) the i.i.d. capacity of an intersymbol interference (ISI) channel with inputs confined to binary values. We use the low-density-parity-check (LDPC) degree sequences optimization method proposed by Richardson, Shokrollahi and Urbanke (see IEEE Trans. Inform. Theory, vol.47, p.619-37, February 2001) and appropriately modify it for ISI channels.