Implementation of TCM encoder and decoder for forward error correction
Kshitij Saratkar, Sachin Meshram, Vandana Bade
This paper presents the technique to design the area efficient trellis code modulation decoder and encoder. The best encoding technique is convolutional encoding as convolutional encoding improves the error performance of communicational channel. But this will increase the bandwidth requirement of system. The trellis code modulation (TCM) can achieve the better error performance without Bandwidth expansion or extra power. This technique is aims to reduce the hardware requirement of the TCM decoder by simply using the Look-Up Tables (LUTs) in the design. In this technique we will directly use the Look-Up tables (LUTs). There are two LUTs use in this technique, and they are hamming distance look-up table (HDLUT), and Output look-up table (OLUT). Instead of designing a circuit to compute the hamming distance in decoding algorithm i.e. viterbi decoding, we pre-calculating the hamming distance and store in the look-up table. Another look-up table use is the output look-up table (OLUT) which gives the output of the viterbi decoder.