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, Glavieux, 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.
Turbo codes make it possible to increase available bandwidth without increasing the power of a transmission, or they can be used to decrease the amount of power used to transmit at a certain data rate. Its main drawback is a relatively high latency, which makes it unsuitable for some applications. For satellite use, this is not of great concern, since the transmission distance itself introduces latency due to the limited speed of light. Turbo codes are used extensively in 3G mobile telephony standards.