Turbo code
Turbo codes are a class of recently-developed high-performance error correction codes finding use in deep-space satellite communications and other applications where designers seek to achieve maximal information transfer over a limited-bandwidth communication link in the presence of data-corrupting noise. Of all practical error correction methods known to date, Turbo codes come closest to approaching the Shannon Limit, the theoretical limit of maximum information transfer rate over a noisy channel.
The method was introduced by Berrou, Glaviuex, and Thitimajshima in their 1993 paper: "Near Shannon Limit error-correcting coding and decoding: Turbo-codes" published in the Proceedings of IEEE International Communications Conference. Turbo code refinements and implementation are an area of active research at a number of universities.
Prior to Turbo codes, the best known technique combined a Reed-Solomon error correction block code with a Viterbi algorithm convolutional code.