公开(公告)号：US3686576A

公开(公告)日：1972-08-22

申请号：US3686576D

申请日：1970-12-18

Applicant: IBM

Inventor： ABRAMSON PAUL ,  GOERTZEL GERALD

IPC: H04Q1/457

CPC classification number: H04Q1/457

Abstract: A parallel tone detection method, system and apparatus includes using several generators for providing square waves at the fundamental frequency of several parallel tones to be detected. An unknown input signal is clipped and then AND gates are used to test for the simultaneous presence of the A.C. polarities of both the unknown input signal and each respective square wave. A lowpass filter is connected to each of the outputs of the AND gates associated with each tone. The outputs of the filters for each tone are connected into a corresponding analogue OR gate, which is one of a series of analogue OR gates. Then it is determined whether the outputs of any of the analogue OR gates exceeds a standard value. If it does then a circuit determines which analogue OR gate produces the largest output to identify the tone received.

Abstract translation: 并行音检测方法，系统和装置包括使用几个发生器来提供要检测的几个并行音调的基频的方波。 未知输入信号被削波，然后与门用于测试未知输入信号和每个相应方波的同时存在A.C.极性。 低通滤波器连接到与每个音调相关联的与门的每个输出。 每个音调的滤波器的输出连接到相应的模拟或门，它是一系列模拟或门之一。 然后确定任何模拟或门的输出是否超过标准值。 如果这样做，则电路确定哪个模拟或门产生最大输出以识别所接收的音。