| 摘要 |
PURPOSE:To correct an error without using an error correction code when an audio signal is transmitted after being made into a digital code by utilizing spectrum information. CONSTITUTION:Size (a), (b), (c), and (d) for temporal transition tn, tn+1, tn+2, and tn+3 of power at each of frequencies f1-fn in continuous sampling are accumulated in first to fourth registers 6a-6d. and the power values Cex, Cin of the third register 6c at time tn+2 are calculated respectively from the power values (a), (b) and (b), (d) of the first and second registers 6a, 6b and the second and fourth registers 6b, 6d at time tn, tn+1 and time tn+1, tn+3, and a level range is estimated at each of frequencies f1-fn from the power value C' of the third register 6c at time tn+2 and the power values Cex, Cin, and the error is corrected by using C' when a received power value is within the range, and the intermediate value Cca of Cex and Cin when it is outside the range. |
