| 摘要 |
PURPOSE:To simplify the means which detects failures of a voice adding circuit as a whole in the circuit which adds for every (n) time slots within the frames which are constituted with (m) time slots. CONSTITUTION:In a voice adding circuit, which adds for every (n) time slots within the frames which are constituted with (m) time slots, a check time is provided in a specific time slots within a frame and a pattern inserter 110 which inputs a pattern 101 that is set in advance during the check time and a pattern detecting circuit 150, which compares the voice-added result and the beforehand expected pattern in the check time and detects failures of the voice adding circuit as a whole including an adding circuit peripheral, are provided. |
