公开(公告)号：US4485483A

公开(公告)日：1984-11-27

申请号：US476738

申请日：1983-03-18

申请人： Emil L. Torick ,  Thomas B. Keller

发明人： Emil L. Torick ,  Thomas B. Keller

IPC分类号： H03G7/00 ,  H04B1/64 ,  H04H20060101 ,  H04H1/00 ,  H04H20/48 ,  H04H20/88 ,  H04H5/00

CPC分类号： H04H20/48 ,  H03G7/00 ,  H04B1/64

摘要： An FM stereophonic radio broadcasting system in which stereophonically related audio frequency source signals L and R are matrixed to obtain stereophonic sum and difference signals M and S, respectively. At the transmitter, the difference signal, is compressed, and the conventional difference signal and the compressed difference signal modulate respective quadrature-related sub-carriers of the same frequency to develop two double-sideband, suppressed-carrier signals, the frequency of the sub-carriers being sufficiently high as to assure a frequency gap between the lower sidebands of the modulated sub-carrier signals and the sum signal M. The M signal, the aforementioned suppressed-carrier signals, and a pilot signal having a frequency which lies within the frequency gap, are combined and frequency-modulated onto a high frequency carrier for the purpose of transmitting the same to one or more remote receivers. The receiver includes an expander for complementarily expanding the received compressed difference signal, and the expanded noise-reduced difference signal is combined with the received sum signal to reproduce the audio frequency source signals L and R. The system increases the broadcast coverage area over that of current biphonic service yet is compatible with existing monophonic and biphonic receivers.

摘要翻译： 立体声相关的音频源信号L和R被矩阵化的FM立体声无线电广播系统分别获得立体声和差分信号M和S。 在发射机处，差分信号被压缩，并且传统的差分信号和压缩的差分信号调制相同频率的各个正交相关子载波以产生两个双边带，抑制载波信号，子频率 载波足够高以确保调制的子载波信号的下边带与和信号M之间的频率间隙.M信号，前述的抑制载波信号和具有位于该信号中的频率的导频信号 频率间隙被组合和频率调制到高频载波上，以将其发送到一个或多个远程接收机。 接收机包括用于互补地扩展接收的压缩差分信号的扩展器，并且扩展的降噪差信号与接收到的和信号相组合，以再现音频源信号L和R.系统增加广播覆盖区域超过 目前的双声道服务与现有的单声道和双声道接收机兼容。