| 摘要 |
PURPOSE:To check code error simply and economically, by detecting that the polarity of head bit of the 1st signal group having predetermined code constitution and code length is opposite to the polarity of the 2nd signal group in which the polarity of the entire code is the same and the code length is not determined. CONSTITUTION:A code detector 2 detects the change in the polarity of a reception signal RV inputted to a shift register 1 to check whether a given length of signals succeeding to it coincide with the 1st signal group or not. While thie time, a mask circuit 3 inhibits the operation of an error bit count section 5. When this inhibition is released, the section 5 counts the error in the 2nd signal until the code detection section 2 detects the 1st signal of the next frame. A signal corresponding to the bit number in error is outputted to a discrimination output terminal by a control section 6. |
