Enhancement the Performance of OFDM based on Multiwavelets Using Turbo Codes
Abstract: In wireless
communication systems, the main challenge is to provide a high data rate and
reliable transmission over a frequency selective fading channel. Orthogonal
Frequency Division Multiplexing (OFDM) is a very attractive technique for high
data rate transmission with better bandwidth efficiency. In this paper, the
effectiveness of turbo codes is utilized to develop a new approach for an OFDM
system based on a Discrete Multiwavelet Critical-Sampling Transform
(OFDM-DMWCST). The use of turbo coding in an OFDM-DMWCST system is useful in
providing the desired performance at higher data rates. Two types of turbo
codes were used in this work, i.e., Parallel Concatenated Convolutional Codes
(PCCCs) and Serial Concatenated Convolutional Codes (SCCCs). In both types, the
decoding is performed by the iterative decoding algorithm based on the log-MAP
(Maximum A Posteriori) algorithm. The simulation results showed that, the
turbo-coded OFDM-DMWCST system achieves large coding gain with lower
Bit-Error-Rate (BER), therefore, offering a higher data rate under different
channel conditions. In addition, the PCCCs offer better performance than SCCCs.
Keywords: OFDM, multiwavelet
critical-sampling transform, turbo codes, wireless channels, bit error rate
Author: Sameer A. Dawood, F.
Malek, M. S. Anuar, HA Rahim
Journal Code: jptkomputergg150134
