Back to Back Channel Bank The connection of voice frequency and signaling leads between channel banks to allow dropping (i. E. Removing) and inserting (i. E. Adding) of channels.

• 背对背信息处理单元两个信息处理单元之间的话音频率和信令引导连接,允许对信道进行卸除(即删除)和插入(即添加)操作。