WO1990006636A1 - Two-way radio with voice storage - Google Patents

Two-way radio with voice storage Download PDF

Info

Publication number
WO1990006636A1
WO1990006636A1 PCT/US1989/005176 US8905176W WO9006636A1 WO 1990006636 A1 WO1990006636 A1 WO 1990006636A1 US 8905176 W US8905176 W US 8905176W WO 9006636 A1 WO9006636 A1 WO 9006636A1
Authority
WO
WIPO (PCT)
Prior art keywords
voice
communication channel
available
transmitter
way radio
Prior art date
Application number
PCT/US1989/005176
Other languages
French (fr)
Inventor
Daniel K. Nichols
Original Assignee
Motorola, Inc.
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Motorola, Inc. filed Critical Motorola, Inc.
Priority to KR1019900701634A priority Critical patent/KR930008783B1/en
Priority to JP2501256A priority patent/JPH0656965B2/en
Publication of WO1990006636A1 publication Critical patent/WO1990006636A1/en

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B1/00—Details of transmission systems, not covered by a single one of groups H04B3/00 - H04B13/00; Details of transmission systems not characterised by the medium used for transmission
    • H04B1/38—Transceivers, i.e. devices in which transmitter and receiver form a structural unit and in which at least one part is used for functions of transmitting and receiving
    • H04B1/40—Circuits
    • H04B1/44—Transmit/receive switching
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B1/00—Details of transmission systems, not covered by a single one of groups H04B3/00 - H04B13/00; Details of transmission systems not characterised by the medium used for transmission
    • H04B1/38—Transceivers, i.e. devices in which transmitter and receiver form a structural unit and in which at least one part is used for functions of transmitting and receiving
    • H04B1/40—Circuits
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04M—TELEPHONIC COMMUNICATION
    • H04M1/00—Substation equipment, e.g. for use by subscribers
    • H04M1/72—Mobile telephones; Cordless telephones, i.e. devices for establishing wireless links to base stations without route selection
    • H04M1/724—User interfaces specially adapted for cordless or mobile telephones
    • H04M1/72403—User interfaces specially adapted for cordless or mobile telephones with means for local support of applications that increase the functionality
    • H04M1/7243—User interfaces specially adapted for cordless or mobile telephones with means for local support of applications that increase the functionality with interactive means for internal management of messages
    • H04M1/72433—User interfaces specially adapted for cordless or mobile telephones with means for local support of applications that increase the functionality with interactive means for internal management of messages for voice messaging, e.g. dictaphones
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W4/00—Services specially adapted for wireless communication networks; Facilities therefor
    • H04W4/06—Selective distribution of broadcast services, e.g. multimedia broadcast multicast service [MBMS]; Services to user groups; One-way selective calling services
    • H04W4/10—Push-to-Talk [PTT] or Push-On-Call services
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W76/00—Connection management
    • H04W76/40—Connection management for selective distribution or broadcast
    • H04W76/45—Connection management for selective distribution or broadcast for Push-to-Talk [PTT] or Push-to-Talk over cellular [PoC] services
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W4/00—Services specially adapted for wireless communication networks; Facilities therefor
    • H04W4/12—Messaging; Mailboxes; Announcements

Definitions

  • This invention relates to two-way radios in general, and in particular to radios having a voice storage means, which can be utilized to store and later transmit a voice message.
  • Known voice storage radios are utilized for voice mailbox purposes. That is, voice messages are either received and stored by the radio for later review, or the message is stored and later transmitted on command or request. These approaches provide for either incoming or outgoing voice mail.
  • radios When radios are operated on shared frequencies, it is important that only a single radio transmit on any give frequency , within a geographical area at a time.
  • a radio is operating in a carrier squelch mode, the user can readily ascertain if the channel is in use by whether the radio is unsquelched, in which case the radio is producing an audio output.
  • coded squelch operation such as subaudible tone or digital code
  • a monitor switch is often provided to permit the radio user to defeat the coded squelch operation to monitor the channel for activity.
  • Some systems provide automatic transmit inhibit, preventing transmission by the radio if a signal is present on the channel.
  • a radio user desires to transmit a message on a busy channel, he must wait until the channel is clear prior to articulating the message. This is often a disruption to the user who wishes to proceed with other activities, but instead must remain ready to actuate the radio and talk when the channel becomes available. It is desirable to provide a means permitting the user to articulate his message inspite of a busy condition on the channel.
  • the two- way radio includes a receiver with means for determining if a communication channel is available.
  • a transmitter is provided for transmitting voice messages on the communication channel.
  • the radio includes voice input means and voice storage means.
  • a control means is responsive to the voice input means and the receiver means to direct voice messages from the voice input means to the transmitter for transmission when the communication is available. When the communication channel is not available, voice messages are directed to the voice storage means for later transmission when the channel is available.
  • control means is further responsive to the receiver means to direct voice messages from the voice storage means to the transmitter for transmission when the communication channel becomes available.
  • the receiver means includes a squelch circuit.
  • the voice input means includes a microphone and an activation switch.
  • the voice storage means includes a digitizer for digitizing voice signals and a memory for storing the digitized voice signals.
  • the voice storage means includes a digital-to-analog converter for converting digitized voice signals to analog signals prior to transmission.
  • FIG. 1 is a block diagram of a two-way radio in accordance with the present invention.
  • FIG. 2 is a flowchart illustrating the operation of the radio of FIG. 1.
  • a two-way radio 10 includes an antenna 12 which is selectively connected to a receiver 14 or to a transmitter 16 by a T/R switch 18 in a conventional manner.
  • Received audio signals from receiver 14 are applied to audio circuits 20 for amplification prior to being applied to a speaker 22.
  • the receiver 14 includes a squelch circuit 15 which provides a squelch output that is applied to an input of a controller 24.
  • An output of controller 24 provides a mute control signal to audio circuits 20.
  • the controller 24, which preferably comprises a microprocessor, is connected to a memory 26 in a conventional manner.
  • the controller also includes output lines for controlling the T/R switch 18, receiver 14 and transmitter 16.
  • a microphone 28, comprising voice input means includes a push-to-talk (PTT) switch, comprising an activation switch, which provides a control signal to an input of controller 24. Audio signals from microphone 28 are supplied to a switch 30, which is controlled by an output line of controller 24. One output of switch 30 is connected to the input of a digitizer 32 which is used to digitize voice signals and supply the digitized signals to controller 24 for storage in memory 26. The digitizer 32 operates under the control of controller 24 which may process the digitized signals prior to storage using known data compression or protection techniques. Another output of switch 30 is connected to an input of a second switch 34 which is also controlled by controller 24. A speech synthesizer 36 is connected to the controller for receiving digitized voice signals from controller 24. The output of speech synthesizer 36 is connected to a second input of switch 34. The output of switch 34 supplies the audio input signal to the transmitter 16.
  • PTT push-to-talk
  • the operation of radio 10 may be best understood by reference to flow chart of FIG. 2.
  • the controller 24 monitors the PTT signal from microphone 28. As illustrated at decision block 50, if the PTT switch is not actuated, the controller continues to monitor the PTT signal. If the PTT switch is actuated, the controller 24 mutes the audio circuits 20 (block 52) and determines if the channel is busy based upon the squelch signal of receiver 14 (block 54). If the channel is not busy the voice message is transmitted (block 56). Controller 24 actuates switches 30 and 34 to route audio signals from microphone 28 to transmitter 16, which is actuated on and T/R switch 18 connects antenna 12 to the transmitter output for radiating the modulated RF signals.
  • the radio begins voice digitization and storage (block 58).
  • Switch 30 is actuated to route audio signals from microphone 28 to digitizer 32.
  • the digitized signals are stored in memory 26.
  • the controller 24 continues to monitor the receiver squelch output during this process (block 60). The storage continues as long as the channel remains busy and the PTT remains actuated (subject to available memory capacity).
  • the stored speech is synthesized and transmitted while continuing to digitized the voice signal (block 62).
  • the controller 24 reads the stored digitized voice from the memory 26 and applies it to speech synthesizer 36.
  • Switch 34 is actuated to supply the synthesized speech to the transmitter 16, which is actuated on and its output is applied via T/R switch 18 to antenna 12.
  • additional voice signals continue to be digitized and stored.
  • digitization and storage ceases (block 66) but the transmission continues until the complete message has been synthesized and transmitted (block 68).
  • digitization ceases when the PTT 29 is released (block 72).
  • the controller 25 monitors the squelch signal until the channel becomes available (block 74).
  • the stored message is then synthesized and transmitted (block 76).
  • the controller 24 uses the receiver squelch signal to determine channel availability, the controller can include a timer 35 for adding a random time delay at blocks 54, 60, and 74 prior to deciding that the channel is not busy. This will delay initiation of transmissions to resolve contention issues on the channel.

Landscapes

  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Human Computer Interaction (AREA)
  • Business, Economics & Management (AREA)
  • General Business, Economics & Management (AREA)
  • Multimedia (AREA)
  • Transceivers (AREA)
  • Mobile Radio Communication Systems (AREA)
  • Transmitters (AREA)
  • Noise Elimination (AREA)
  • Input Circuits Of Receivers And Coupling Of Receivers And Audio Equipment (AREA)
  • Circuits Of Receivers In General (AREA)

Abstract

A two-way radio (10) includes a receiver (14) having a squelch circuit (15) for determining if a communication channel is available. A transmitter (16) is provided for transmitting voice messages on the channel. When the communication channel is available, voice signals are directed from a microphone (28) to the transmitter (16) for transmission. When the communication channel is not available, the voice signals are automatically directed to a digitizer (32) where they are digitized. The digitized voice signals are stored in a memory (26) for later transmission when the channel becomes available.

Description

Two-Way Radio With Voice Storage
Background of the Invention
This invention relates to two-way radios in general, and in particular to radios having a voice storage means, which can be utilized to store and later transmit a voice message. Known voice storage radios are utilized for voice mailbox purposes. That is, voice messages are either received and stored by the radio for later review, or the message is stored and later transmitted on command or request. These approaches provide for either incoming or outgoing voice mail.
When radios are operated on shared frequencies, it is important that only a single radio transmit on any give frequency , within a geographical area at a time. Where a radio is operating in a carrier squelch mode, the user can readily ascertain if the channel is in use by whether the radio is unsquelched, in which case the radio is producing an audio output. For coded squelch operation, such as subaudible tone or digital code, a monitor switch is often provided to permit the radio user to defeat the coded squelch operation to monitor the channel for activity. Some systems provide automatic transmit inhibit, preventing transmission by the radio if a signal is present on the channel.
Where a radio user desires to transmit a message on a busy channel, he must wait until the channel is clear prior to articulating the message. This is often a disruption to the user who wishes to proceed with other activities, but instead must remain ready to actuate the radio and talk when the channel becomes available. It is desirable to provide a means permitting the user to articulate his message inspite of a busy condition on the channel.
Summary of the Invention
This radio with voice storage permits the user to articulate a voice message regardless of whether the channel is busy. The two- way radio includes a receiver with means for determining if a communication channel is available. A transmitter is provided for transmitting voice messages on the communication channel. The radio includes voice input means and voice storage means. A control means is responsive to the voice input means and the receiver means to direct voice messages from the voice input means to the transmitter for transmission when the communication is available. When the communication channel is not available, voice messages are directed to the voice storage means for later transmission when the channel is available.
In one aspect of the invention, the control means is further responsive to the receiver means to direct voice messages from the voice storage means to the transmitter for transmission when the communication channel becomes available. In another aspect of the invention, the receiver means includes a squelch circuit. In still another aspect of the invention, the voice input means includes a microphone and an activation switch. In yet another aspect of the invention, the voice storage means includes a digitizer for digitizing voice signals and a memory for storing the digitized voice signals. In another aspect of the invention, the voice storage means includes a digital-to-analog converter for converting digitized voice signals to analog signals prior to transmission.
Brief Description of the Drawings FIG. 1 is a block diagram of a two-way radio in accordance with the present invention.
FIG. 2 is a flowchart illustrating the operation of the radio of FIG. 1.
Description of the Preferred Embodiment
Referring now by characters of reference to the drawings, and first to FIG. 1 , it will be understood that a two-way radio 10 includes an antenna 12 which is selectively connected to a receiver 14 or to a transmitter 16 by a T/R switch 18 in a conventional manner.
Received audio signals from receiver 14 are applied to audio circuits 20 for amplification prior to being applied to a speaker 22. The receiver 14 includes a squelch circuit 15 which provides a squelch output that is applied to an input of a controller 24. An output of controller 24 provides a mute control signal to audio circuits 20. The controller 24, which preferably comprises a microprocessor, is connected to a memory 26 in a conventional manner. The controller also includes output lines for controlling the T/R switch 18, receiver 14 and transmitter 16.
A microphone 28, comprising voice input means, includes a push-to-talk (PTT) switch, comprising an activation switch, which provides a control signal to an input of controller 24. Audio signals from microphone 28 are supplied to a switch 30, which is controlled by an output line of controller 24. One output of switch 30 is connected to the input of a digitizer 32 which is used to digitize voice signals and supply the digitized signals to controller 24 for storage in memory 26. The digitizer 32 operates under the control of controller 24 which may process the digitized signals prior to storage using known data compression or protection techniques. Another output of switch 30 is connected to an input of a second switch 34 which is also controlled by controller 24. A speech synthesizer 36 is connected to the controller for receiving digitized voice signals from controller 24. The output of speech synthesizer 36 is connected to a second input of switch 34. The output of switch 34 supplies the audio input signal to the transmitter 16.
The operation of radio 10 may be best understood by reference to flow chart of FIG. 2. The controller 24 monitors the PTT signal from microphone 28. As illustrated at decision block 50, if the PTT switch is not actuated, the controller continues to monitor the PTT signal. If the PTT switch is actuated, the controller 24 mutes the audio circuits 20 (block 52) and determines if the channel is busy based upon the squelch signal of receiver 14 (block 54). If the channel is not busy the voice message is transmitted (block 56). Controller 24 actuates switches 30 and 34 to route audio signals from microphone 28 to transmitter 16, which is actuated on and T/R switch 18 connects antenna 12 to the transmitter output for radiating the modulated RF signals. When the PTT switch is released, transmission ceases and the receiver can be unmuted if their is a signal present on the channel. In the event that the channel is busy when the PTT is actuated, the radio begins voice digitization and storage (block 58). Switch 30 is actuated to route audio signals from microphone 28 to digitizer 32. The digitized signals are stored in memory 26. The controller 24 continues to monitor the receiver squelch output during this process (block 60). The storage continues as long as the channel remains busy and the PTT remains actuated (subject to available memory capacity).
If the channel becomes available during the digitization process, the stored speech is synthesized and transmitted while continuing to digitized the voice signal (block 62). The controller 24 reads the stored digitized voice from the memory 26 and applies it to speech synthesizer 36. Switch 34 is actuated to supply the synthesized speech to the transmitter 16, which is actuated on and its output is applied via T/R switch 18 to antenna 12. As long as the PTT 29 remains actuated (block 64), additional voice signals continue to be digitized and stored. When the PTT is released, digitization and storage ceases (block 66) but the transmission continues until the complete message has been synthesized and transmitted (block 68). Where the complete message has been digitized prior to the channel becoming available, as indicated by the PTT not being actuated at block 70, digitization ceases when the PTT 29 is released (block 72). The controller 25 monitors the squelch signal until the channel becomes available (block 74). The stored message is then synthesized and transmitted (block 76).
By digitizing and storing voice messages, channel interference is avoided and the user of the radio 10 is able to enter a voice message without delay and without any user intervention other than the normal actuation of a PTT switch or its equivalent. While the controller 24 uses the receiver squelch signal to determine channel availability, the controller can include a timer 35 for adding a random time delay at blocks 54, 60, and 74 prior to deciding that the channel is not busy. This will delay initiation of transmissions to resolve contention issues on the channel. claim as my invention:

Claims

Claims
1. A two-way radio comprising: a receiver including means for determining if a communication channel is available, a transmitter for transmitting voice messages on the communication channel, voice input means, voice storage means, and control means responsive to the voice input means and said receiver, the control means directing voice messages from the voice input means to the transmitter for transmission when the communication channel is available and to the voice storage means for storage when the communication channel is not available.
2. A two-way radio as defined in claim 1 , in which: the control means is further responsive to said receiver means to automatically direct voice messages from the voice storage means to the transmitter for transmission when said communication channel becomes available.
3. A two-way radio as defined in claim 2, in which: said receiver means includes a squelch circuit.
4. A two-way radio as defined in claim 1 , in which : the voice input means includes a microphone and an activation switch.
5. A two-way radio as defined in claim 1 , in which: the voice storage means includes a digitizer for digitizing voice signals, and a memory for storing digitized voice signals.
6. A two-way radio as defined in claim 5, in which: the voice storage means further includes a digital-to- analog converter for converting stored digitized voice signals to analog signals prior to transmission.
7. A two-way radio comprising: a receiver including a squelch circuit for determining if a communication channel is available, a transmitter for transmitting voice messages on the communication channel, voice input means including a microphone and an activation switch, voice storage means including a digitizer and a memory, and control means responsive to the activation switch and to said squelch circuit , the control means automatically directing voice signals from the microphone to the transmitter for transmission when the communication channel is available and to the voice storage means for storage in the memory when the communication channel is not available.
8. A method of transmitting a voice message via a radio transmitter comprising the steps of: determining whether a communication channel is available, when the communication channel is available, transmitting the voice message without storing the message, and when the communication channel is not available, storing the voice message until the communication channel becomes available, and then transmitting the stored voice message.
1 1
9. A method of transmitting a voice message as defined in claim 8 in which the step of storing the voice message includes the steps of: first digitizing the voice message, and then storing the digitized voice message in a memory.
10. A method of transmitting a voice message as defined in claim 9, in which the step of determining whether the communication channel is available includes detecting the presence or absence of a signal on the channel by using a squelch circuit.
PCT/US1989/005176 1988-12-02 1989-11-20 Two-way radio with voice storage WO1990006636A1 (en)

Priority Applications (2)

Application Number Priority Date Filing Date Title
KR1019900701634A KR930008783B1 (en) 1988-12-02 1989-11-20 Two-way radio with voice storage
JP2501256A JPH0656965B2 (en) 1988-12-02 1989-11-20 Voice storage type two-way wireless device

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US27900188A 1988-12-02 1988-12-02
US279,001 1988-12-02

Publications (1)

Publication Number Publication Date
WO1990006636A1 true WO1990006636A1 (en) 1990-06-14

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PCT/US1989/005176 WO1990006636A1 (en) 1988-12-02 1989-11-20 Two-way radio with voice storage

Country Status (6)

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EP (1) EP0446297A4 (en)
JP (1) JPH0656965B2 (en)
KR (1) KR930008783B1 (en)
AU (1) AU626616B2 (en)
CA (1) CA1309142C (en)
WO (1) WO1990006636A1 (en)

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2771566A1 (en) * 1997-11-26 1999-05-28 Bihan Alain Le Proximity portable message receiver/transmitter
EP1209852A1 (en) * 2000-11-27 2002-05-29 Siemens Aktiengesellschaft Method and device for data transmission
EP1323289A1 (en) * 1998-03-13 2003-07-02 Terence E. Sumner Accepting and conveying a voice mail message
EP1505844A1 (en) * 2003-08-06 2005-02-09 Lucent Technologies Inc. Buffering initial talk burst
WO2005057967A1 (en) * 2003-12-08 2005-06-23 Kyocera Wireless Corp. Optimized push-to-talk call setup
US7245940B2 (en) 2004-10-19 2007-07-17 Kyocera Wireless Corp. Push to talk voice buffering systems and methods in wireless communication calls
US11364004B2 (en) 2018-02-08 2022-06-21 Covidien Lp System and method for pose estimation of an imaging device and for determining the location of a medical device with respect to a target

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US4495647A (en) * 1982-12-06 1985-01-22 Motorola, Inc. Digital voice storage mobile
US4742514A (en) * 1986-03-25 1988-05-03 Motorola, Inc. Method and apparatus for controlling a TDM communication device

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JPS592997B2 (en) * 1980-05-22 1984-01-21 富士通株式会社 static memory
JPS61133093A (en) * 1984-12-03 1986-06-20 Oki Electric Ind Co Ltd Semiconductor memory device
JPH07118192B2 (en) * 1985-07-23 1995-12-18 日本電気株式会社 Semiconductor memory device
US4821310A (en) * 1987-12-22 1989-04-11 Motorola, Inc. Transmission trunked radio system with voice buffering and off-line dialing

Patent Citations (2)

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Publication number Priority date Publication date Assignee Title
US4495647A (en) * 1982-12-06 1985-01-22 Motorola, Inc. Digital voice storage mobile
US4742514A (en) * 1986-03-25 1988-05-03 Motorola, Inc. Method and apparatus for controlling a TDM communication device

Cited By (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2771566A1 (en) * 1997-11-26 1999-05-28 Bihan Alain Le Proximity portable message receiver/transmitter
EP1323289A4 (en) * 1998-03-13 2006-05-31 Terence E Sumner Accepting and conveying a voice mail message
EP1323289A1 (en) * 1998-03-13 2003-07-02 Terence E. Sumner Accepting and conveying a voice mail message
EP1209852A1 (en) * 2000-11-27 2002-05-29 Siemens Aktiengesellschaft Method and device for data transmission
EP1505844A1 (en) * 2003-08-06 2005-02-09 Lucent Technologies Inc. Buffering initial talk burst
JP2005057785A (en) * 2003-08-06 2005-03-03 Lucent Technol Inc Buffering initial talk burst
US7266382B2 (en) 2003-08-06 2007-09-04 Lucent Technologies Inc. Method and apparatus for decreasing perceived push-to-talk call set-up time using a buffer for initial speech burst
JP4718140B2 (en) * 2003-08-06 2011-07-06 アルカテル−ルーセント ユーエスエー インコーポレーテッド Buffering of initial speech burst (initialtalkburst)
KR101083913B1 (en) 2003-08-06 2011-11-15 알카텔-루센트 유에스에이 인코포레이티드 Buffering initial talk burst
WO2005057967A1 (en) * 2003-12-08 2005-06-23 Kyocera Wireless Corp. Optimized push-to-talk call setup
US7260414B2 (en) 2003-12-08 2007-08-21 Kyocera Wireless Corp. Optimized push-to-talk call setup
US7245940B2 (en) 2004-10-19 2007-07-17 Kyocera Wireless Corp. Push to talk voice buffering systems and methods in wireless communication calls
US11364004B2 (en) 2018-02-08 2022-06-21 Covidien Lp System and method for pose estimation of an imaging device and for determining the location of a medical device with respect to a target
US11896414B2 (en) 2018-02-08 2024-02-13 Covidien Lp System and method for pose estimation of an imaging device and for determining the location of a medical device with respect to a target

Also Published As

Publication number Publication date
KR900702671A (en) 1990-12-08
AU626616B2 (en) 1992-08-06
EP0446297A1 (en) 1991-09-18
JPH04502691A (en) 1992-05-14
AU4667689A (en) 1990-06-26
EP0446297A4 (en) 1992-08-05
JPH0656965B2 (en) 1994-07-27
KR930008783B1 (en) 1993-09-15
CA1309142C (en) 1992-10-20

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