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公开(公告)号:US5568655A
公开(公告)日:1996-10-22
申请号:US338034
申请日:1994-11-14
申请人: Jouko Heinonen , Henrik Sunell , Matti Koskinen
发明人: Jouko Heinonen , Henrik Sunell , Matti Koskinen
CPC分类号: H04H20/34 , G08B3/1066 , H04H2201/13
摘要: Apparatus for detecting the presence of a paging signal at 57 KHz in a frequency modulated transmission includes a phase locked loop (14) which is sensitive to the presence of a pager signal. The phase locked loop (14) which produces phase adjusting pulses at a repetition rate representative of the presence or absence of a pager signal. The phase adjusting pulses are fed to a detector (22) which produces a bistable signal which is either low, indicating no pager signal, or high, indicating the presence of a pager signal.
摘要翻译: 用于在频率调制传输中用于检测在57KHz的寻呼信号的存在的装置包括对寻呼信号的存在敏感的锁相环(14)。 锁相环(14)以表示寻呼机信号存在或不存在的重复频率产生相位调整脉冲。 相位调整脉冲被馈送到检测器(22),该检测器产生双稳态信号,其为低电平,不指示寻呼机信号,或高电平,指示寻呼机信号的存在。