PCM Signal processing apparatus

摘要

A PCM signal processing apparatus adapted to receive successive transmission blocks, each of which comprise time-interleaved PCM data, error correction and error detection words. The apparatus has detecting means responsive to the error detection words for detecting errors in a received transmission block and error identifying means for identifying errors in each of the time-interleaved words included in the received transmission block which has been detected. A de-interleaver is provided for time-deinterleaving each received transmission block to recover a de-interleaved block comprising de-interleaved PCM and error-correction words, with errors in the de-interleaved words being respectively identified. A syndrome generating device is coupled to the de-interleaver for generating error syndromes using the de-interleaved PCM and error-correction words in the de-interleaved block. An error correcting device responsive to the error syndromes corrects erroneous PCM words in the de-interleaved block as a function of the remaining error free PCM and the error-correction words in the de-interleaved block. An error compensating device is responsive to the identification of errors by the error identifying device and compensates the erroneous PCM words in the de-interleaved block with a substitute PCM word when error correction by said error correcting device is impossible. An inhibit device inhibits the error correcting device when all of the error detection words in the de-interleaved block are identified as erroneous and it discontinues inhibiting when the relationship between the identification by the error identifying device and the error syndrome indicates that no error exists.