In [1] [2], product accumulate (PA) codes were proposed and shown to be a class of simple and provably good codes for rate . This work investigates the generalized product accumulate (GPA) codes which have rates over the entire range and which are also “good” both in the maximum likelihood (ML) sense and under the iterative approach. Analysis concentrates on the weight distribution over the cod...

Seizures are thought to originate from a failure of inhibition to quell hyperactive neural circuits, but the nature of this failure remains unknown. Here we combine high-speed two-photon imaging with electrophysiological recordings to directly evaluate the interaction between populations of interneurons and principal cells during the onset of seizure-like activity in mouse hippocampal slices. B...

Product accumulate codes are a special case of differentially coded low density parity check (LDPC) codes. This work analyzes the noncoherent performance of PA codes and general differentially-coded LDPC codes on flat Rayleigh fading channels using extrinsic information transfer charts, and proposes a convergence-constraint method to design good LDPC ensembles matched to differential coding.

Method Rate d SNRgap(DE) SNRgap(approx.)