Description: This script simulates the classical turbo encoding-decoding system.
It simulates parallel concatenated convolutional codes.
Two component rate 1/2 RSC (Recursive Systematic Convolutional) component encoders are assumed.
First encoder is terminated with tails bits. (Info + tail) bits are scrambled and passed to
the second encoder, while second encoder is left open without tail bits of itself.
Random information bits are modulated into +1/-1, and transmitted through a AWGN channel.
Interleavers are randomly generated for each frame.
Log-MAP algorithm without quantization or approximation is used.
By making use of ln(e^x+e^y) = max(x,y) + ln(1+e^(-abs(x-y))),
the Log-MAP can be simplified with a look-up table for the correction function.
If use approximation ln(e^x+e^y) = max(x,y), it becomes MAX-Log-MAP.
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File list (Check if you may need any files):
turbo_sys_demo.m
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