| 摘要 |
<P>PROBLEM TO BE SOLVED: To solve the following problem: there is the risk of detecting a reception data error by demodulated output data when noise is inputted in a receiver by an FSK system. <P>SOLUTION: In a signal extraction means 6, the output of a frequency discrimination means 3 is sampled by a predetermined sampling pulse and the minimum value V1 and the maximum value V2 are extracted from values sampled in a predetermined section 2T. Then, an input signal stabilization detection means 7 calculates a minimum signal change amount between the previous time and this time ¾this time V1-previous time V1 (=V1')¾ and a maximum signal change amount between the previous time and this time ¾this time V2-previous time V2 (=V2')¾, determines that it is a stable signal when either one is equal to or smaller than a predetermined value Va, determines that it is an instable signal and data-outputs a fixed value such as "0000" when both exceed the predetermined value Va. <P>COPYRIGHT: (C)2011,JPO&INPIT |
