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What is convolution code with example?

What is convolution code with example?

Example of Generating a Convolutional Code The code-rate, Rc = k/n = 1/2 . The input string is streamed from right to left into the encoder. From the above example, we can see that any particular binary convolutional encoder is associated with a set of binary inputs, a set of binary outputs and a set of states.

What is the meaning of convolutional code?

In telecommunication, a convolutional code is a type of error-correcting code that generates parity symbols via the sliding application of a boolean polynomial function to a data stream. Time invariant trellis decoding allows convolutional codes to be maximum-likelihood soft-decision decoded with reasonable complexity.

How do turbo codes work?

Turbo codes are a much more developed way of integrating information redundancy. They are based on the transmission of the initial message in three copies. The first copy is the raw, non-encoded information. The second is modified by encoding each bit of information using an algorithm shared by the coder and decoder.

Is convolutional code linear code?

Convolutional codes are linear codes over the field of one-sided infinite sequences. The symbols can be from any field but we will just consider symbols from GF(2).

Are turbo codes convolutional codes?

The turbo code is the name of a class of convolutional codes which developed by parallel concatenating two convolutional code blocks which are identical. This new class of channel error control code is well known for its high performance at low to moderate signal to noise ratio (SNR).

How are RSC codes used in turbo coding?

In Turbo codes, particularly the parallel structure, Recursive systematic convolutional (RSC) codes working in parallel are used to create the “random” versions of the message. The parallel structure uses two or more RSC codes, each with a different interleaver.

How did Andrew Viterbi decode the convolutional code?

In 1967 Andrew Viterbi determined that convolutional codes could be maximum-likelihood decoded with reasonable complexity using time invariant trellis based decoders — the Viterbi algorithm. Other trellis-based decoder algorithms were later developed, including the BCJR decoding algorithm.

When did Claude Berrou invent the convolutional code?

Recursive systematic convolutional codes were invented by Claude Berrou around 1991. These codes proved especially useful for iterative processing including the processing of concatenated codes such as turbo codes.

Why was the introduction of turbo codes so revolutionary?

Turbo codes were so revolutionary at the time of their introduction that many experts in the field of coding did not believe the reported results. When the performance was confirmed a small revolution in the world of coding took place that led to the investigation of many other types of iterative signal processing.

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