| 摘要 |
<p>PURPOSE:To specify a block of a fault line and a relay device without replacement of the relay device with respect to the monitor method of a faulty line and the device characteristic in the IF relay digital radio equipment and in a radio relay system employing the IF relay digital radio equipment in which a frequency of an RF (radio frequency) signal is decreased once into a frequency of an IF (intermediate frequency) and then the IF signal is restored into the RF signal for the relay. CONSTITUTION:The IF relay digital radio equipment 3 is provided with a loopback means 15 applying loopback connection of an IF signal of a line to other line and a loopback control means 16 controlling the loopback means 15 by remote control and the radio line monitor method controls the loopback means to form a loopback loop thereby specifying a fault location.</p> |
