Performance enhancement of tone detection and FSK detection using hybrid
echo cancellation
    1.
    发明授权
    Performance enhancement of tone detection and FSK detection using hybrid echo cancellation 失效
    使用混合回波消除的音调检测和FSK检测的性能增强

    公开(公告)号:US5943407A

    公开(公告)日:1999-08-24

    申请号:US991482

    申请日:1997-12-16

    CPC分类号: H04M1/573

    摘要: Type 2 caller ID/call waiting (CIDCW) customer premises equipment (CPE) is provided which has a greatly improved method of detecting tones indicating the availability of call information regarding an incoming call while the customer premises equipment is in an off-hook condition. A hybrid echo canceler (HEC) algorithm is added to the customer premises equipment (CPE) to suppress the signal from the microphone of the customer premises equipment from being included in the signal analyzed for the presence of tones. Thus, the microphone of the customer premises equipment need not be muted upon detection of the alerting CAS tone sequence in a Caller ID service. The HEC algorithm runs substantially continuously in a preferred embodiment, and may be combined with a conventionally operating HEC which cancels reflections due to the hybrid or telephone line interface.

    摘要翻译: 提供了类型2呼叫者ID /呼叫等待(CIDCW)客户驻地设备(CPE),其具有大大改进的方法,用于在客户驻地设备处于摘机状态时检测指示有关来电的呼叫信息的可用性的音调。 将混合回波消除器(HEC)算法添加到客户驻地设备(CPE)中以抑制来自客户驻地设备的麦克风的信号被包括在分析为存在音调的信号中。 因此,在呼叫者ID服务中检测到警报CAS音调序列时,客户端设备的麦克风不需要被静音。 HEC算法在优选实施例中基本连续地运行,并且可以与常规操作的HEC组合,其消除由于混合或电话线路接口引起的反射。