JPS6420761A - Telephone terminal - Google Patents
Telephone terminalInfo
- Publication number
- JPS6420761A JPS6420761A JP17767987A JP17767987A JPS6420761A JP S6420761 A JPS6420761 A JP S6420761A JP 17767987 A JP17767987 A JP 17767987A JP 17767987 A JP17767987 A JP 17767987A JP S6420761 A JPS6420761 A JP S6420761A
- Authority
- JP
- Japan
- Prior art keywords
- noise
- value
- level
- gain
- transmission system
- 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.)
- Granted
Links
Abstract
PURPOSE:To attain natural speech quality under low noise and to attain excellent noise suppression effects under high noise by controlling the noise suppression effects of a transmission system in response to the output from a detection microphone. CONSTITUTION:A variable attenuator 12 bringing a gain of the transmission system to a constant value at all times when the input sound pressure level of a transmitter 1 is higher than a prescribed threshold value and to a lower value than a fixed value when the input level is equal to or less than the threshold value, a microphone 3 detecting surrounding noise, and a control means for receiving a signal in response to the level of the noise from the output of the microphone to control the variable attenuator, are provided. When the surrounding noise level is high, the variable part of the gain of the transmission system is brought to a lower value than the fixed constant value and when the surrounding noise is low, the variable part of the gain is brought to a value close to the fixed constant value by controlling the variable attenuator 12. Thus, natural speech characteristics are realized.
Priority Applications (6)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP62177679A JPH06101760B2 (en) | 1987-07-15 | 1987-07-15 | Telephone terminal |
CA000571870A CA1291837C (en) | 1987-07-15 | 1988-07-13 | Electronic telephone terminal having noise suppression function |
US07/219,607 US4908855A (en) | 1987-07-15 | 1988-07-15 | Electronic telephone terminal having noise suppression function |
EP88111401A EP0299507B1 (en) | 1987-07-15 | 1988-07-15 | Electronic telephone terminal having noise suppression function |
AU19078/88A AU601861B2 (en) | 1987-07-15 | 1988-07-15 | Electronic telephone terminal having noise suppression function |
DE3887786T DE3887786T2 (en) | 1987-07-15 | 1988-07-15 | Electronic telecommunication device with noise reduction function. |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP62177679A JPH06101760B2 (en) | 1987-07-15 | 1987-07-15 | Telephone terminal |
Publications (2)
Publication Number | Publication Date |
---|---|
JPS6420761A true JPS6420761A (en) | 1989-01-24 |
JPH06101760B2 JPH06101760B2 (en) | 1994-12-12 |
Family
ID=16035210
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP62177679A Expired - Lifetime JPH06101760B2 (en) | 1987-07-15 | 1987-07-15 | Telephone terminal |
Country Status (1)
Country | Link |
---|---|
JP (1) | JPH06101760B2 (en) |
Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS4831361A (en) * | 1971-08-28 | 1973-04-24 | ||
JPS528126A (en) * | 1975-07-04 | 1977-01-21 | Japan Exlan Co Ltd | Process for manufacturing flame- retarded acrylic fibers with improved fiber properties |
JPS57115765U (en) * | 1981-12-01 | 1982-07-17 |
-
1987
- 1987-07-15 JP JP62177679A patent/JPH06101760B2/en not_active Expired - Lifetime
Patent Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS4831361A (en) * | 1971-08-28 | 1973-04-24 | ||
JPS528126A (en) * | 1975-07-04 | 1977-01-21 | Japan Exlan Co Ltd | Process for manufacturing flame- retarded acrylic fibers with improved fiber properties |
JPS57115765U (en) * | 1981-12-01 | 1982-07-17 |
Also Published As
Publication number | Publication date |
---|---|
JPH06101760B2 (en) | 1994-12-12 |
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