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    Frequency modulation broadcast transmitter synchronization method
    1.
    发明授权
    Frequency modulation broadcast transmitter synchronization method 失效
    频率调制广播发射机同步方法

    公开(公告)号：US5216717A

    公开(公告)日：1993-06-01

    申请号：US661999

    申请日：1991-03-01

    申请人： Patrice Bourcet ,  Alain Komly ,  Michel Seguin

    发明人： Patrice Bourcet ,  Alain Komly ,  Michel Seguin

    IPC分类号： H04H20/67

    CPC分类号： H04H20/67

    摘要： A synchronized broadcast network comprises a main transmitter transmitting an audio source signal to a plurality of receiver/transmitter units remote from each other and from the main transmitter, the receiver/transmitter units broadcasting the audio signal using frequency modulation. In the main transmitter the audio source signal is digitized by sampling it at a predetermined sampling frequency. A digitized signal representing the sampled audio signal is transmitted to the receiver/transmitter units. In each receiver/transmitter unit a reference signal representing the sampling frequency is derived from the received digitized signal and the received digitized signal is passed through a succession of digital processing stages including a stage in which a carrier derived from the reference signal is digitally modulated and a stage in which the result of the digital modulation is digital-to-analog converted. In one of the digital processing stages the received digitized signal is delayed for a predetermined time in order to synchronize the phase of the receiver/transmitter units. All the digital processing stages are synchronized to the reference signal to obtain identical digital modulation of the same carrier for all the receiver/transmitter units. The result of the digital-to-analog conversion stage is transposed to a final frequency derived from the reference signal for broadcasting the analog audio signal using frequency modulation with the same modulation, phase and carrier at all receiver/transmitter units.

    摘要翻译： 同步广播网络包括：主发射机，将音频源信号发送到彼此远离的多个接收机/发射机单元，并且从主发射机发射，所述接收机/发射机单元使用频率调制来广播音频信号。 在主发射机中，音频源信号通过以预定的采样频率进行采样来数字化。 表示采样的音频信号的数字化信号被发送到接收机/发射机单元。 在每个接收机/发射机单元中，从所接收的数字化信号中导出表示采样频率的参考信号，并且所接收的数字化信号通过一系列数字处理级，包括从参考信号导出的载波被数字调制的级， 其中数字调制的结果被数字到模拟转换的阶段。 在数字处理级之一中，接收的数字化信号被延迟预定时间，以便使接收机/发射机单元的相位同步。 所有数字处理级与参考信号同步，以获得所有接收机/发射机单元相同载波的相同数字调制。 数字 - 模拟转换级的结果被转置到从参考信号导出的最终频率，用于在所有接收机/发射机单元处使用具有相同调制，相位和载波的频率调制广播模拟音频信号。