公开(公告)号：US3735048A

公开(公告)日：1973-05-22

申请号：US3735048D

申请日：1971-05-28

Applicant: MOTOROLA INC

Inventor： TOMSA S ,  EASTMOND B

IPC: H04B7/08 ,  H04M11/06

CPC classification number: H04B7/082

Abstract: An information transmission system for transmitting data signals simultaneously with audio signals in an audio channel includes a gate circuit at the transmitting unit for interrupting the transmitted audio at a rate controlled by the data signal, and a detector at the receiving unit for detecting the interruptions in the audio and reconstructing the data signal from the interruptions. The duration of the interruptions is selected to be short enough so as not to be readily detectable audibly. The system is suitable for use in a multiple radio-receiver system wherein signals are transmitted from spaced receivers to a central station with data signals indicating the quality of the signals received at each receiver.

Abstract translation: 一种用于在音频通道中与音频信号同时发送数据信号的信息传输系统包括：发送单元处的门电路，用于以由数据信号控制的速率中断发送的音频;以及接收单元处的检测器， 从中断音频和重构数据信号。 选择中断的持续时间足够短，以免听起来容易察觉。 该系统适用于多个无线电接收机系统，其中信号从间隔的接收机传输到中心站，数据信号指示在每个接收机处接收到的信号的质量。

公开(公告)号：US3851253A

公开(公告)日：1974-11-26

申请号：US36390673

申请日：1973-05-25

Applicant: MOTOROLA INC

Inventor： EASTMOND B

IPC: H03G3/34

CPC classification number: H03G3/344

Abstract: An automatically adjustable squelch circuit which responds to detected noise and modulation signals from a receiver discriminator to actuate a switch and includes control circuitry which responds to receipt of a command signal to initialize sequential development of control signals. A variable attenuator coupled to the discriminator and to the control circuit responds to each of the control signals in sequence to attenuate signals coupled therethrough from the discriminator by a predetermined amount. The attenuated signals are coupled to a detector which develops the detection signal when the signals coupled thereto exceed a predetermined level. The control circuit is operative in response to the detection signal to terminate the sequence and maintain the last developed control signal in the sequence.

Abstract translation: 一种自动调节的静噪电路，其响应来自接收器鉴频器的检测到的噪声和调制信号以致动开关，并且包括控制电路，响应于接收到命令信号以初始化控制信号的顺序显影。 耦合到鉴别器和控制电路的可变衰减器依次响应于每个控制信号，以将从该鉴别器耦合的信号衰减预定量。 衰减的信号耦合到检测器，当检测信号耦合到其上时，其产生检测信号超过预定电平。 控制电路响应于检测信号而工作以终止序列并维持序列中最后显影的控制信号。

公开(公告)号：US3824470A

公开(公告)日：1974-07-16

申请号：US33360173

申请日：1973-02-20

Applicant: MOTOROLA INC

Inventor： EASTMOND B

IPC: H04B7/00 ,  H04B7/08 ,  H04B7/155 ,  H04B7/26 ,  H04B3/06

CPC classification number: H04B7/084

Abstract: A communications system, including portable transmitters and several remote receivers connected to a base station by means of a limited bandwidth transmission link (such as a telephone line), wherein the receivers include an encoder for transmitting the information over the transmission link and removing a small band of the information and inserting a carrier frequency, amplitude and frequency modulated by the coded squelch signals and the information signal strength signals, and the base station includes a decoder.

Abstract translation: 一种通信系统，包括便携式发射机和通过有限带宽传输链路（例如电话线路）连接到基站的几个远程接收机，其中接收机包括用于通过传输链路传输信息的编码器， 并且插入由编码的静噪信号和信息信号强度信号调制的载波频率，频率和频率，并且基站包括解码器。

公开(公告)号：ZA7500093B

公开(公告)日：1976-04-28

申请号：ZA7500093

申请日：1975-01-06

Applicant: MOTOROLA INC

Inventor： EASTMOND B

IPC: H04B1/10 ,  H03G3/34 ,  G08C

CPC classification number: H03G3/342

公开(公告)号：ZA7593B

公开(公告)日：1976-04-28

申请号：ZA7593

申请日：1975-01-06

Applicant: MOTOROLA INC

Inventor： EASTMOND B

IPC: H04B1/10 ,  H03G3/34 ,  G08C