Turbo Code is Formed from the Parallel Concatenation of Two Codes

The first turbo code, based on convolutional encoding, was introduced in 1993 by Berrou etal. Since then, several schemes have been proposed and the term “turbo codes” has been generalized to cover block codes as well as convolutional codes. Simply put, a turbo code is formed from the parallel concatenation of two codes separated by an interleaver. The turbo principle is a general way of processing data in receivers so that no information is wasted. This technique corresponds to an iterative exchange of soft information between different blocks in a communications receiver in order to improve overall system performance. It has opened up a new way of thinking in the construction of communication algorithms. This method was introduced in a system of error control for data transmission, called turbo code. This family of Forward Error Codes (FEC) consists of two key design innovations: concatenated encoding and iterative decoding. The turbo principle has been extended into new receiver topologies such as turbo detection, turbo equalization, turbo-coded modulation, turbo MIMO, etc. In the case of transmission systems with interference, such an iterative receiver, known as turbo equalizer or turbo detector achieves significant gains in BER performance, compared with a non-iterative scheme. However, the design of high throughput, low complexity and low latency architectures for a receiver that contains an iterative process is a great challenge. The Orthogonal Frequency Division