ERROR CORRECTION CODE AND APPARATUS FOR THE CORRECTION OF ERENTIALLY ENCODED QUADRATURE PHASE SHIFT KEYED DATA (DQPSK)

摘要

AN ERROR CORRECTION CODE AND APPARATUS FOR THE CORRECTION OF DIFFERENTIALLY ENCODED QUADRATURE PHASE SHIFT KEYED DATA (DQPSK) This specification describes a convolutional code and apparatus for the correction of errors in differentially encoded quadrature phase shift keyed data (DQPSK). In each sequence of forty bits 24 are information bits and the remainder are parity bits. Two parity bits are generated for each three information bit set in the sequence in accordance with the following equations: where i?, i? and i? are the three information bits in the set associated with the parity bits P? and p? while the other information bits are from the seven sets of the sequence preceding the set associated with the parity bits.