JPS6481557A - Automobile telephone set - Google Patents

Automobile telephone set

Info

Publication number
JPS6481557A
JPS6481557A JP23754687A JP23754687A JPS6481557A JP S6481557 A JPS6481557 A JP S6481557A JP 23754687 A JP23754687 A JP 23754687A JP 23754687 A JP23754687 A JP 23754687A JP S6481557 A JPS6481557 A JP S6481557A
Authority
JP
Japan
Prior art keywords
signal
ring tone
digital signal
digital
converter
Prior art date
Legal status (The legal status 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 status listed.)
Pending
Application number
JP23754687A
Other languages
Japanese (ja)
Inventor
Tokiyoshi Mitani
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Oki Electric Industry Co Ltd
Original Assignee
Oki Electric Industry Co Ltd
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 Oki Electric Industry Co Ltd filed Critical Oki Electric Industry Co Ltd
Priority to JP23754687A priority Critical patent/JPS6481557A/en
Publication of JPS6481557A publication Critical patent/JPS6481557A/en
Pending legal-status Critical Current

Links

Abstract

PURPOSE:To offer an automobile telephone set preventing production of a ring tone itself by providing a digital signal processing means setting a pseudo signal of an opposite phase cancelling a ring tone based on the characteristic of a transmission signal or a reception signal and a ring tone path. CONSTITUTION:A caller voice entering a microphone 1 is amplified by an amplifier 2, converted into a digital signal by an A/D converter 13a and given to one input terminal of a digital signal processing unit 14. The digital signal processor 14, based on the reception signal, applies the digital processing such as echo canceller to estimate the pseudo signal of an opposite phase corresponding to the ring tone and cancelling it with respect to the inputted voice signal. The voice signal processed by the digital signal processor 14 is given to a D/A converter 15a from one output terminal and supplied to a radio equipment from the transmission output terminal 5 via switches 16, 17.
JP23754687A 1987-09-24 1987-09-24 Automobile telephone set Pending JPS6481557A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP23754687A JPS6481557A (en) 1987-09-24 1987-09-24 Automobile telephone set

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP23754687A JPS6481557A (en) 1987-09-24 1987-09-24 Automobile telephone set

Publications (1)

Publication Number Publication Date
JPS6481557A true JPS6481557A (en) 1989-03-27

Family

ID=17016932

Family Applications (1)

Application Number Title Priority Date Filing Date
JP23754687A Pending JPS6481557A (en) 1987-09-24 1987-09-24 Automobile telephone set

Country Status (1)

Country Link
JP (1) JPS6481557A (en)

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5742250A (en) * 1980-08-28 1982-03-09 Nec Corp Data transfer system between plural processors
JPS6038958A (en) * 1983-08-12 1985-02-28 Nec Corp Loudspeaker telephone set
JPS60200676A (en) * 1984-03-26 1985-10-11 Nippon Telegr & Teleph Corp <Ntt> Telephone set circuit having holding tone sending function

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5742250A (en) * 1980-08-28 1982-03-09 Nec Corp Data transfer system between plural processors
JPS6038958A (en) * 1983-08-12 1985-02-28 Nec Corp Loudspeaker telephone set
JPS60200676A (en) * 1984-03-26 1985-10-11 Nippon Telegr & Teleph Corp <Ntt> Telephone set circuit having holding tone sending function

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