Asymptotic anytime reliability of LDPC convolutional codes

Abstract:

The concept of anytime information theory was developed to provide a fundamental framework of reliable causal communication of bit streams through noisy channels. Within this framework anytime reliability, where the error rate of a particular bit improves exponentially with the decoding latency, plays a vital role. It has been shown that classes of linear and nonlinear random tree codes are anytime reliable at the cost of a decoding complexity growing exponential with time. As a more ”practical” solution we investigate LDPC Convolutional Codes (LDPC-CCs), where recently a slidingwindow message-passing decoder was proposed to provide efficient trade-offs between decoding latency and error rate. Moreover the decoding latency can be set and changed on-the-fly as required. We consider non-terminated LDPC-CCs with increasing memory to enable random-like linear tree codes. We propose an ensemble of protograph-based LDPC-CCs that together with an expanding-window message-passing decoder can ensure anytime reliability asymptotically over a binary erasure channel.
On-going work is focused on anytime reliability of finite-length LDPC-CCs.

Presentation Slides

Biography:Lars K. Rasmussen got his Ph.D. degree from Georgia Institute of Technology (Atlanta, Georgia, USA) in 1993. He has since then worked at the Institute for Telecommunications Research at the University of South Australia, the Centre for Wireless Communications at the National University of Singapore, Chalmers University of Technology in Sweden, and is now a full professor with the School of Electrical Engineering, and the ACCESS Linnaeus Center at the KTH Royal Institute of Technology in Sweden. He is an associate editor for IEEE Transactions on Communications, and has been a guest editor for IEEE Journal on Selected Areas in Communications. He is a co-founder of Cohda Wireless Pty Ltd, operating out of Adelaide, Australia; a leading company in the area of physical-layer solutions for vehicular safety and ITS systems.