The FPGA Implementation of Viterbi Algorithm in Grand Alliance ATSC Systems
It is well known that data transmission over wireless channel are affected by attenuation, distortion, interference
and noise which affect receiver abilities to receive correct information. Convolutional encoding with Viterbi decoding is a
powerful method for forward error correction. They play important role in Digital communications, especially when channel
is noisy and introduces errors in transmission channel. Today data reconstruction in digital communication system requires
design of highest throughput rate. Convolutional codes are used in many communication system due to excellent error
control performance .Convolutional coding is done by combining fixed number of input bits .The input bits are stored in
fixed length shift registers, they are combined with help of mod-2 adders. Operation is similar to binary convolution, and
hence known as convolutional coding .The parallel process Viterbi Decoder with pipelining uses 3-bit soft decision decoding
for estimation of original data streams. Power consumption is reduced, moreover speed of processing is increased.
Keywords- Convolution encoders, Viterbi Decoders, ATSC system.