Forward error correction techniques are used for error correction at the receiving end. Convolutional coding is a FEC technique that is particularly adapted to a channel in which the transmitted signal is mainly damaged by additive white Gaussian noise (AWGN). The Viterbi algorithm is a well-known maximum likelihood algorithm for convolutional code decoding. They have good correction ability and good performance even in very noisy channels. It has been widely implemented in many wireless communication systems to improve the limited capacity of communication channels.
The main objective of this work is to describe the comparative analysis between several FPGA devices for the proposed implementation of Viterbi Decoder design resource optimization. The basis of comparison is the simulation and the synthesized result. In this document, the optimized resource Viterbi Decoder has been designed using Trace architecture again. The proposed Viterbi Decoder with speed ½ and restriction length 3 has been designed using VHDL, simulated with Xilinx ISE Simulator and synthesized with Xilinx Synthesis Tool (XST). The Viterbi decoder is compatible with many common standards such as DVB, 3GPP2, 3GPP, IEEE 802.16 and LTE.
Encoding the information stream prior to transmission involves adding extra redundancy, which is then used at the receiving end to reconstruct the original sequence, effectively reducing the probability of errors induced by a noisy channel. Different code structures have since been developed, which are known as channel coding. The encoder adds redundant bits to the sender's bit stream to create a codeword. The decoder uses the redundant bits to detect and / or correct as many bit errors as the particular error control code allows. Like any error correction code, a convolutional code works by adding structured redundant information to user data and correcting errors using this information. There have been some
Convolutional decoding methods such as sequential decoding and Viterbi, of which the most commonly used technique is the Viterbi Algorithm (VA). The Viterbi decoding was developed by Andrew. J. Viterbi, founder of Qualcomm Corporation in April 1967. Since then, other researchers have expanded Viterbi's work by finding good convolutional codes, exploring the performance limits of the technique, and varying the design parameters of the decoder to optimize the implementation of The technique in hardware and software. The Viterbi algorithm is being used extensively in many mobile and wireless communication systems for optimal decoding of convolutional codes. The Viterbi alignment is a dynamic programming algorithm to find the most likely sequence of hidden states - called the Viterbi path - which results in a sequence of observed events, especially in the context of Markov information sources and Markov models Hidden. Applications using Viterbi decoding include digital modems and digital cell phones, where low latency, cost of components and power consumption are imperative.