JPS5520423B2 - - Google Patents
Info
- Publication number
- JPS5520423B2 JPS5520423B2 JP12965074A JP12965074A JPS5520423B2 JP S5520423 B2 JPS5520423 B2 JP S5520423B2 JP 12965074 A JP12965074 A JP 12965074A JP 12965074 A JP12965074 A JP 12965074A JP S5520423 B2 JPS5520423 B2 JP S5520423B2
- Authority
- JP
- Japan
- 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.)
- Expired
Links
Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04M—TELEPHONIC COMMUNICATION
- H04M9/00—Arrangements for interconnection not involving centralised switching
- H04M9/08—Two-way loud-speaking telephone systems with means for conditioning the signal, e.g. for suppressing echoes for one or both directions of traffic
- H04M9/085—Two-way loud-speaking telephone systems with means for conditioning the signal, e.g. for suppressing echoes for one or both directions of traffic using digital techniques
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| FR7347136A FR2255762B1 (ja) | 1973-12-21 | 1973-12-21 |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS5094802A JPS5094802A (ja) | 1975-07-28 |
| JPS5520423B2 true JPS5520423B2 (ja) | 1980-06-02 |
Family
ID=9130001
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP12965074A Expired JPS5520423B2 (ja) | 1973-12-21 | 1974-11-12 |
Country Status (6)
| Country | Link |
|---|---|
| US (1) | US3975588A (ja) |
| JP (1) | JPS5520423B2 (ja) |
| DE (1) | DE2455584C3 (ja) |
| FR (1) | FR2255762B1 (ja) |
| GB (1) | GB1439107A (ja) |
| IT (1) | IT1026644B (ja) |
Families Citing this family (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE2659028C3 (de) * | 1976-12-27 | 1979-05-31 | Dasy Inter S.A., Genf (Schweiz) | Schaltungsanordnung zum Verhindern von Rückkopplungen |
| US4491694A (en) * | 1981-10-23 | 1985-01-01 | Michael Harmeyer | Telephone to stereo amplifier interface coupling |
| GB2122851B (en) * | 1982-06-10 | 1986-03-19 | Standard Telephones Cables Ltd | Loudspeaking telephones |
| GB2137458B (en) * | 1983-03-01 | 1986-11-19 | Standard Telephones Cables Ltd | Digital handsfree telephone |
| US4583237A (en) * | 1984-05-07 | 1986-04-15 | At&T Bell Laboratories | Technique for synchronous near-instantaneous coding |
| US4696032A (en) * | 1985-02-26 | 1987-09-22 | Siemens Corporate Research & Support, Inc. | Voice switched gain system |
| US4726062A (en) * | 1985-12-11 | 1988-02-16 | Harris Corporation | Duplex hands-free communications circuit |
| US4741018A (en) * | 1987-04-24 | 1988-04-26 | Motorola, Inc. | Speakerphone using digitally compressed audio to control voice path gain |
| US5228076A (en) * | 1989-06-12 | 1993-07-13 | Emil Hopner | High fidelity speech encoding for telecommunications systems |
| US5010570A (en) * | 1990-02-20 | 1991-04-23 | Motorola, Inc. | Method for active feedback suppression |
Family Cites Families (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3562448A (en) * | 1968-06-21 | 1971-02-09 | Bell Telephone Labor Inc | Common control digital echo suppression |
| US3673355A (en) * | 1970-09-02 | 1972-06-27 | Bell Telephone Labor Inc | Common control digital echo suppression |
| US3735055A (en) * | 1971-11-05 | 1973-05-22 | Bell Telephone Labor Inc | Method for improving the settling time of a transversal filter adaptive echo canceller |
| US3821494A (en) * | 1972-07-14 | 1974-06-28 | Ibm | Digital echo suppressor with direct table look up control by delta coded signals |
| US3832491A (en) * | 1973-02-13 | 1974-08-27 | Communications Satellite Corp | Digital voice switch with an adaptive digitally-controlled threshold |
-
1973
- 1973-12-21 FR FR7347136A patent/FR2255762B1/fr not_active Expired
-
1974
- 1974-11-12 JP JP12965074A patent/JPS5520423B2/ja not_active Expired
- 1974-11-23 DE DE2455584A patent/DE2455584C3/de not_active Expired
- 1974-11-27 GB GB5136174A patent/GB1439107A/en not_active Expired
- 1974-11-29 IT IT29991/74A patent/IT1026644B/it active
- 1974-12-13 US US05/532,548 patent/US3975588A/en not_active Expired - Lifetime
Also Published As
| Publication number | Publication date |
|---|---|
| DE2455584A1 (de) | 1975-07-03 |
| GB1439107A (en) | 1976-06-09 |
| IT1026644B (it) | 1978-10-20 |
| JPS5094802A (ja) | 1975-07-28 |
| FR2255762A1 (ja) | 1975-07-18 |
| DE2455584C3 (de) | 1978-08-10 |
| FR2255762B1 (ja) | 1976-07-23 |
| US3975588A (en) | 1976-08-17 |
| DE2455584B2 (de) | 1977-12-15 |