LPC-based DTMF receiver for secondary signalling
    1.
    发明授权
    LPC-based DTMF receiver for secondary signalling 失效
    基于LPC的DTMF接收机用于二次信令

    公开(公告)号:US4853958A

    公开(公告)日:1989-08-01

    申请号:US201154

    申请日:1988-06-02

    IPC分类号: H04Q1/457

    CPC分类号: H04Q1/4575

    摘要: A dual tone multi-frequency (DTMF) receiver for use in detecting digitally transmitted signals in the telephone industry. The receiver derives linear predictive coefficients for the digital signals in the data frame. This information is used to compute frequency response magnitudes at the DTMF frequencies. A plurality of magnitude comparisons are then performed to verify the presence of true DTMF signals and concurrently the frequency of these signals is obtained.

    摘要翻译: 一种双音多频(DTMF)接收机,用于检测电话行业中的数字传输信号。 接收器为数据帧中的数字信号导出线性预测系数。 该信息用于计算DTMF频率的频率响应幅度。 然后执行多个幅度比较以验证真实DTMF信号的存在,同时获得这些信号的频率。