Turbo Codes

Abstract

The 20^th century saw the evolution of wireless communications through electromagnetic waves from the first telegraphic transmission in 1895 by Gugliemo Marconi towards the current so-called ‘third generation’ (3G) [1] and WiFi [2] multimedia communication devices that allow to exchange voice, image and data information at speeds of respectively a couple to over fifty megabits per second (Mb/s). This improvement in communications has been particularly accelerated in the second half of the 20^th century thanks to the independent evolution of two fields of science: information theory and microelectronics. The year 1948 is considered as the major landmark in the development of digital technology due to achievements in both fields that would be eventually successfully combined. Claude Shannon on the information theory side set the very founding stone of this science with the definition of one binary unit of information, or bit, as well as the definition of channel capacity. In the same year, William Shockley and his team at Bell laboratories announced the invention of the transistor, which would be used later as the building element of circuits able to process and store bits¹.

This parallel between Shannon’s definition of a bit and the transistor was based on Berrou’s and Glavieux’s introduction to their IEEE Information Theory invited paper of 1998, on the occasion of the 50^th birthday of the transistor and of information theory. The whole article can be found in http://www.itsoc.org/review/frrev.html.