This includes two BCJR
decoders, one for each of the RSCs, a random interleaver ([pi]) and its corresponding deinterleaver ([[pi].sup.-1]).
An iteration of BCJR or MAP decoding algorithm for RSCC requires O(12[OMEGA]([L.sub.1] + [L.sub.2])) floating point operations, where [OMEGA] is the number of states of the convolutional coder.
Therefore, together with BCJR algorithm, the proposed iterative decoder requires at most
One of the most popular MAP decoders used for decoding convolutional code is BCJR decoder.
The [[LAMBDA].sup.e] is again reorganized into fixed length blocks using EREC and applied as a priori information [[GAMMA].sup.a] to the BCJR decoder.
We achieved this by iterative decoding between Chase-like SISO arithmetic decoder and BCJR decoder, with ERECST stage in-between.
3) BCJR algorithm, which is based on the Log Likelihood Ratio, is highly adapted to the BPSK signals.
At the receiver side, before going through the traditional turbo decoding process using the BCJR algorithm, pulse position demodulation comes into play to generate the desired BPSK-like soft decision.
In other words, the iterative turbo decoding, irrespective of the decoding algorithm used (whether BCJR algorithm or Soft Output Viterbi Algorithm (SOVA) or any other algorithm), cannot be operated directly on the received PPM symbols.
As we said before, the decoding algorithm is known as the BCJR algorithm .
La literatura propone en la decodificacion SISO (Soft Input Soft Output) algoritmos tales como Algoritmo de Viterbi salida suave (SOVA) y modificaciones del algoritmo (Maximo A Posteriori) o BCJR, donde se presentan versiones como Log MAP Max [7-11].
[12.] Abrantes, S., Do algoritmo BCJR a descodificacao turbo, Portugal, 2004, en linea: http://paginas.fe.up.pt/%7Esam/textos/De%20BCJR%20a%20turbo.pdf