公开(公告)号：EP0135192A3

公开(公告)日：1987-04-29

申请号：EP84110927

申请日：1984-09-13

申请人： Audicom Corporation

发明人： Howard, Jonathan M.

IPC分类号： H04H01/00 ,  H04L27/10

CPC分类号： H04H20/31

摘要： An audio program is encoded with a subaudible binary code. A first value bit (mark) is a first frequency signal and a second value bit (space) is a second frequency signal. The coded message includes an initialization period constituted by a signal having the mark frequency. In decoding, the mark and space signals are detected through first and second band pass filters specific to the mark and space signal frequencies. The mark and space frequencies are sufficiently different to permit separate filtering. The time duration for each bit of the code is substantial. The decoder through a phase locked loop and integrator reads the bit on the basis of the average value of the bit over the duration of the bit. A synchronization signal provides for synchronous reading of the code. This signal that initiates the decoding operation is generated only in response to the coincident detection of the initialization signal, the notch and a mark response at the phase locked loop.

摘要翻译： 一个音频节目用一个可听的二进制码编码。 第一值位（mark）是第一频率信号，第二值位（空格）是第二频率信号。 编码消息包括由具有标记频率的信号构成的初始化周期。 在解码中，通过专用于标记和空间信号频率的第一和第二带通滤波器来检测标记和空间信号。 标记和空间频率是完全不同的，以允许单独的过滤。 代码的每个位的持续时间是很大的。 通过锁相环和积分器的解码器在位的持续时间内基于位的平均值读取该位。 同步信号提供代码的同步读取。 只有响应于初始化信号的一致检测，陷波和锁相环路上的标记响应才产生启动解码操作的信号。

公开(公告)号：EP0135192A2

公开(公告)日：1985-03-27

申请号：EP84110927.5

申请日：1984-09-13

申请人： Audicom Corporation

发明人： Howard, Jonathan M.

IPC分类号： H04H1/00 ,  H04L27/10

CPC分类号： H04H20/31

摘要： An audio program is encoded with a subaudible binary code. A first value bit (mark) is a first frequency signal and a second value bit (space) is a second frequency signal. The coded message includes an initialization period constituted by a signal having the mark frequency. In decoding, the mark and space signals are detected through first and second band pass filters specific to the mark and space signal frequencies. The mark and space frequencies are sufficiently different to permit separate filtering. The time duration for each bit of the code is substantial. The decoder through a phase locked loop and integrator reads the bit on the basis of the average value of the bit over the duration of the bit. A synchronization signal provides for synchronous reading of the code. This signal that initiates the decoding operation is generated only in response to the coincident detection of the initialization signal, the notch and a mark response at the phase locked loop.

摘要翻译： 一个音频节目用一个可听的二进制码编码。 第一值位（mark）是第一频率信号，第二值位（空格）是第二频率信号。 编码消息包括由具有标记频率的信号构成的初始化周期。 在解码中，通过专用于标记和空间信号频率的第一和第二带通滤波器来检测标记和空间信号。 标记和空间频率是完全不同的，以允许单独的过滤。 代码的每个位的持续时间是很大的。 通过锁相环和积分器的解码器在位的持续时间内基于位的平均值读取该位。 同步信号提供代码的同步读取。 只有响应于初始化信号的一致检测，陷波和锁相环路上的标记响应才产生启动解码操作的信号。