发明名称 |
Electronic telephone terminal having noise suppression function. |
摘要 |
An electronic telephone terminal having a transmitter (1) and a receiver (2), both having an approximately linear acoustic-to-electric transduction characteristics, and having a surrounding noise suppression function, and including a variable attenuator (12) for controlling a gain of a transmission system; a noise detection device (3) for detecting surrounding noise; and a control device (63) for controlling the variable attenuator (12) in such a manner that when a sound pressure level input to the transmitter (1) exceeds a predetermined threshold value, the gain is fixedly set to a constant value, and when the input sound pressure level is equal to or below the predetermined threshold level, the gain is controlled in response to a change in the surrounding noise level detected by the noise detection device (3). |
申请公布号 |
EP0299507(B1) |
申请公布日期 |
1994.02.16 |
申请号 |
EP19880111401 |
申请日期 |
1988.07.15 |
申请人 |
FUJITSU LIMITED |
发明人 |
OHGA, JURO;FUJII, KENSAKU;MASUDA, HIROYUKI;SATO, YUKA |
分类号 |
H04M1/19;H04M1/60;H04M9/08 |
主分类号 |
H04M1/19 |
代理机构 |
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代理人 |
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主权项 |
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地址 |
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