Hardware-efficient turbo coding

By analogy with the cryptographic procedure of stream-ciphering, it is proposed that the weights of the outputs of the encoders used in turbo coding can be controlled, with their resulting combined weights increased. One method of doing this is to combine by means of an XOR gate a binary stream of suitable data with the input to one encoder. The extra effort in decoding is merely to repeat the XOR operation with the same set of data. Some results are given for a simple model system. Evidently this method requires little additional hardware, while potentially simplifying the coding process.