Externally dialed hand-free operator for cellular phones

• US 6,314,179 B1
• Filed: 08/17/1999
• Issued: 11/06/2001
• Est. Priority Date: 08/17/1999
• Status: Expired due to Fees

• Current Assignee: E-Lead Electronic Co., Ltd.
• Original Assignee: E-Lead Electronic Co., Ltd.
• Inventors: Chen, Tonny
• Primary Examiner(s): Chiang, Jack
• Application Number:
  US09/375,497
• Time in Patent Office: 812 Days
• Field of Search: 379/444, 379/446, 379/420, 379/454, 379/455, 379/40, 379/430, 379/388.02, 379/420.01
• US Class Current: 379/388.02
• CPC Class Codes: H04M 1/26 Devices for calling a subscriber H04M1/66 takes precedence
• CPC Class Codes: H04M 1/30 Devices which can set up and transmit only one digit at a time
• CPC Class Codes: H04M 1/6041 Portable telephones adapted for handsfree use
• CPC Class Codes: H04M 1/724 User interfaces specially adapted for cordless or mobile telephones

Abstract

A hand-free operator can be externally dialed via a dialing device. It is more particularly related to an external dialing device, which can be applied to all kinds of cellular phones. Thereby people do not have to keep telephone numbers in memory, they can make direct dials on a hand-free operator by means of telephone numbers stored in advance in a memory unit of a dialing device. It mainly houses a hand-free operator circuit and a dial processing unit in a hand-free operator embodiment that operate in collaboration with a signal cable and a dialing device (DTMF acoustic generator). It enables people to make a dial on cellular phones of all kinds via a hand-free operator without memorizing phone numbers or resorting to phone books, effectively facilitating the use of cellular phones and advancing driving safety.

Claims

1. An externally dialed hand-free system for cellular telephones, comprising:

a cellular telephone adapted to transmit dialing signals for telephone numbers provided as dialing code signals to an input thereof,

a dialing device selectively providing acoustic DTMF tones representing a predetermined telephone number to be dialed; and

,

an hand-free operator circuit coupled to said input of said cellular telephone by a signal cable, said hand-free operator circuit including;

(a) a microphone receiving said acoustic DTMF tones,

(b) an amplifying circuit coupled to said microphone for amplifying electrical signals from said microphone,

(c) a dial processing circuit having an input coupled to an output of said amplifying circuit and an output coupled to said cellular telephone input for converting said received DTMF tones to said dialing code signals, and

(d) a control switch coupled to said dial processing circuit for activating said dial processing circuit to process said DTMF tones subsequently output from said dialing device.

2. The externally dialed hand-free system as recited in claim 1, wherein said hand-free operator circuit is enclosed within a connector plug of the signal cable.

3. The externally dialed hand-free system as recited in claim 1, wherein said hand-free operator circuit is enclosed within a housing disposed between connector plugs disposed at opposing ends of the signal cable.

4. The externally dialed hand-free system as recited in claim 1, wherein said dial processing circuit includes a DTMF decoding unit coupled to said output of said amplifying circuit for decoding said electrical signals representing said DTMF tones.

5. The externally dialed hand-free system as recited in claim 4, wherein said dial processing circuit includes a dial control processing unit coupled to an output of said DTMF decoding unit and said control switch to receive decoded dialing signal from said DTMF decoding unit and activate said cellular telephone into a state for dialing.

6. The externally dialed hand-free system as recited in claim 5, wherein said dial processing circuit further includes a dial decoding circuit having an input coupled to an output of said dial control processing unit and an output coupled to said input of said cellular phone for converting said decoded dialing signals to said dialing code signals.

7. An externally dialed hand-free system for cellular telephones, comprising:

a cellular telephone adapted to transmit dialing signals for telephone numbers provided as dialing code signals to an input thereof;

a dialing device selectively providing acoustic DTMF tones representing a predetermined telephone number to be dialed; and

,

an hand-free operator circuit coupled to said input of said cellular telephone by a signal cable, said hand-free operator circuit including;

(a) a microphone receiving said acoustic DTMF tones,

(b) an amplifying circuit coupled to said microphone for amplifying electrical signals from said microphone,

(c) a DTMF decoding unit coupled to an output of said amplifying circuit for decoding said electrical signals representing said DTMF tones,

(d) a dial control processing unit coupled to an output of said DTMF decoding unit to receive decoded dialing signals from said DTMF decoding unit,

(e) a control switch coupled to said dial control processing unit for initiating said dial control processing unit to process said decoded dialing signals and activate said cellular telephone into a state for dialing, and

(f) a dial decoding circuit having an input coupled to an output of said dial control processing unit and an output coupled to said input of said cellular phone for converting said decoded dialing signals to said dialing code signals.