| 摘要 |
PROBLEM TO BE SOLVED: To provide an apparatus for measuring attenuation during a double-talk, capable of accurately evaluating a performance for communication quality during double-talk, in a telephone set in which an apparatus such as an echo canceller is incorporated. SOLUTION: The apparatus for measuring the attenuation during double-talk in the telephone set 50 includes a measurement signal generator 1 for generating measurement signals; a double-talk signal generator 2 for generating double-talk signals (interference signals); an output signal measurement portion 3 for inputting the measurement signals to one of a reception input portion 56 and a transmission input portion 53, time-delaying and inputting the double-talk signals to the other, and inputting coexisting output signals in which the time without double-talks and the time of double-talks coexist and which are outputted in a reception output portion 54 or a transmission output portion 55; a frequency filter 4 for removing a double-talk signal portion from the coexisting output signals and obtaining attenuation measurement signals; and an attenuation calculating portion 5 for measuring the level at without double-talks and the level at double-talk in the attenuation measurement signals and calculating the attenuation during the double-talk. COPYRIGHT: (C)2010,JPO&INPIT |
