Joint Design Of Turbo Codes And Network Coding

Since Turbo codes are a class of error-correcting codes, which can approach the Shannon bound and have been used widely; network coding can improve the throughput of the wireless network significantly. Therefore, the joint design of turbo codes and network coding not only ensures the reliability of transmission, but also can improve the transmission efficiency of wireless networks. So this paper studies the joint design of turbo codes and network coding in-depth.This paper introduces the relay-related technologies and network coding firstly; then describes some existing schemes of joint channel-network coding; finally design schemes of joint turbo-network coding and decoding which used for two users and multiple users are proposed.In the proposed scheme of joint turbo-network coding and decoding used for two users, two implementation methods are introduced:one is based on punctures, and the other is based on modulations. At the relay node, the former achieves the purpose of regulating transmission efficiency adaptively by removing some bits; the latter regulates the forwarding efficiency by using modulations of different orders. At the destination node, they both use joint decoding. Analyses and simulations show that the tradeoff between forwarding efficiency at the relay and decoding performance at the destination can be achieved.In the proposed scheme of joint turbo-network coding and decoding used for multiple users, the relay only helps the users whose information can be decoded correctly at the relay to forward information during one time slot, with performing joint decoding at the destination. The scheme applies to the cases of any number of users, and has the advantage of easy and flexible to handle. The relay forwarding efficiency increases with increasing forwarding users.