| 摘要 |
PURPOSE:To improve the detection capability by generating a signal interruption detection signal when either of an output of a means discriminating the presence of a base band signal and an output of a means of AND processing of its inputs is consecutively missing for a prescribed time or over. CONSTITUTION:Suppose that all of binary digital signals S11 - S22 or a clock signal CLK is missing or all of the signals S11,S21 of S12,S22 is missing, then base band signal outputs IS,QS of D/A converters 12I,12Q are both missing or either of them is missing. Thus, a discrimination output of comparators 21I,21Q of a signal interrupt detection circuit 20 goes to an L level. Then an L level signal, i.e., an alarm signal is generated after laps of a prescribed time from the generation of input interruption from either or both of one-shot multivibrators 22I,22Q is generated and the alarm signal is outputted via an AND circuit 23. Thus, input interruption of the binary digital signals S11 - S22 is detected without missing of detection. |
