| 摘要 |
<P>PROBLEM TO BE SOLVED: To detect a fault of a receiver of a radio base station with a simple system. <P>SOLUTION: An SW 201 performs switching either to connect an input terminal of a receiver 133 to an antenna 114 or to terminate it. An LNA (low noise amplifier) 205 amplifies a signal to be input with low distortion. SW 202, 203 switch a first route via the LNA 205 and a second route 204 not via the LNA 205. An AGC-AMP 211 controls a gain so as to fix an output and amplifies a signal with the controlled gain. A base station control unit terminates the input terminal of the receiver using the SW 201 and inputs thermal noise in the LNA 205. Furthermore, the SW 202 and 203 are changed over to judge normality of the receiver when a first gain of the AGC-AMP 211 in connection to the first route, a second gain of the AGC-AMP 211 in connection to the second route, and a difference of the first and the second gains are settled within a prescribed range, respectively. <P>COPYRIGHT: (C)2008,JPO&INPIT |
