Abstract
Serial Concatenation Convolutional Codes (SCCCs) encoder is built using a serial
concatenation of two Recursive Systematic Convolutional (RSC) encoders, separated by an
interleaver. These two RSC encoders depending on the trellis termination criteria are software
implemented and the performance of each one of them is analyzed under different conditions
and circumstances. The output data from the encoder are multiplied by an amplitude matrix
(AM) at the transmitter side and the Inverse of Amplitude Matrix (IAM) at the receiver side.
The reliability estimation, log-likelihood algebra, and soft channel outputs for Soft Output
Viterbi Algorithm (SOVA) are examined. Then the modified Viterbi metric that incorporates
a-priori information used for SOVA decoding is derived. A low memory implementation of
the SOVA decoder is presented. The iterative SOVA for SCCCs is described with illustrative
examples. The behavior of the SCCCs encoder-decoder scheme is tested under different
circumstances with AM and without AM at the AWGN and Rayleigh fading channels with
unlike frame sizes (FS) and constraint length (K). The results show that the performance of
system with AM outperforms the other conventional system that worked without AM.
concatenation of two Recursive Systematic Convolutional (RSC) encoders, separated by an
interleaver. These two RSC encoders depending on the trellis termination criteria are software
implemented and the performance of each one of them is analyzed under different conditions
and circumstances. The output data from the encoder are multiplied by an amplitude matrix
(AM) at the transmitter side and the Inverse of Amplitude Matrix (IAM) at the receiver side.
The reliability estimation, log-likelihood algebra, and soft channel outputs for Soft Output
Viterbi Algorithm (SOVA) are examined. Then the modified Viterbi metric that incorporates
a-priori information used for SOVA decoding is derived. A low memory implementation of
the SOVA decoder is presented. The iterative SOVA for SCCCs is described with illustrative
examples. The behavior of the SCCCs encoder-decoder scheme is tested under different
circumstances with AM and without AM at the AWGN and Rayleigh fading channels with
unlike frame sizes (FS) and constraint length (K). The results show that the performance of
system with AM outperforms the other conventional system that worked without AM.
Keywords
AM
Concatenation Codes
Frame size
RSC
SCCCs
SOVA