Performance Improvement of Turbo Codes Using Soft Input Decryption

A novel method to improve the performance of Turbo Codes using Soft Input Decryption is presented in this paper. A channel coding technique that provides performance near to Shannon´s limit is Turbo code. To achieve optimum decoding, Maximum A-Posteriori Probability (MAP) decoding is used for Turbo Codes. The Soft Input Decryption method is based on the combination of cryptography and channel coding. Cryptographic checksum called hash is used to improve the performance of Turbo coding. Hash value is appended to the transmitted information for data integrity verification. The least reliable soft output values of the channel decoder are modified until the data integrity verification is successful. Results show that a significant improvement in the performance of channel coding can be achieved using soft input decryption.