Transmission speed predicting apparatus and transmission speed predicting method

Abstract

First data is repeatedly sent out by using various sorts of transfer speeds by a receiver; a preselected number of polarity information about the first data is sequentially compared with each other by a first incoincident number detector to detect a first incoincident number; a most likelihood pathmetric value is detected by Viterbi-decoding each of second data a most likelihood detector; the polarity information of the respective second data is compared with the polarity information of corresponding coded data by a second incoincident number detector to detect a second incoincident number; and the transfer speed of the transmission processing is predicted by a transfer speed predicting circuit based on the first incoincident number, the most likelihood pathmetric value, and the second incoincident number, acquired every transfer period. Even when a relatively large number of errors happen to occur in the decoded data, the transfer speed can be predicted by greatly reducing the errors by using the first incoincident number acquired without being adversely influenced by the occurrence condition of the error.