| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide an oscillation detector applied to a radio repeater capable of automatically detecting whether or not the radio repeater is oscillated. SOLUTION: In the case of performing communication by TDMA(time division multiplex communication system), the level of DC components included in the output signals of this radio repeater is judged in a judgement circuit 16 and supplied to a monitoring circuit 17. Also, the level of AC components included in the output signals is judged in the judgement circuit 15 and supplied to the monitoring circuit 17. In the TDMA, a frame to which plural channels are allocated is turned to a communication unit. In the meantime, the input levels of the respective channels are normally different. Thus, normally, the AC components are included in the output signals. On the other hand, when the radio repeater is oscillated, since the level of the output signals is fixed at all times, the AC components are not included. In the monitoring circuit 17, when a DC level reaches a stipulated level equivalent to an upper limit and an AC level is less than a reference level, it is judged that the radio repeater is oscillated.</p> |
