| 7680655 |
Method and apparatus for measuring the quality of speech transmissions that use speech compression |
Michael R. Kosek, Alan H. Matten, Harvey Siy, Peng Zhang |
2010-03-16 |
| 5953330 |
Communication switch |
Thomas L. Hiller, Ronald A. Spanke, John J. Stanaway, Jr., Alex Lawrence Wierzbicki, Meyer J. Zola |
1999-09-14 |
| 5619564 |
Tone detector with improved performance in the presence of speech |
Ali N. Jablway |
1997-04-08 |
| 5331632 |
Expandable time slot interchanger |
Calvin Aaron |
1994-07-19 |
| 5251208 |
Digital signal processor synchronous network |
Philip Chao, Alan H. Matten, Charles E. Stroud |
1993-10-05 |
| 4761751 |
Method and apparatus for generating digital signals representing periodic samples of a sine wave |
— |
1988-08-02 |
| 4644568 |
Timing signal distribution arrangement |
Mike Arthur Derrenberger |
1987-02-17 |
| 4460806 |
Dual tone multifrequency and dial pulse receiver |
Gordon Lin |
1984-07-17 |
| 4403320 |
Line status detection in a digital concentrator system |
— |
1983-09-06 |
| 4398284 |
Concentrator in a subscriber loop digital carrier system |
— |
1983-08-09 |
| 4394756 |
Generation of busy signals in a digital concentrator |
— |
1983-07-19 |
| 4380810 |
Loopback test |
— |
1983-04-19 |
| 4357701 |
Digital concentrator terminal synchronization |
— |
1982-11-02 |
