| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a radio apparatus with self-diagnosis function which is able to perform self-diagnosis according to a loop-back system, while reducing the circuit scale, even if the output frequency of a local generator differs between at transmission and at reception. <P>SOLUTION: In a radio apparatus 10, a loop-back switch 32 of a switch section 14 is disposed between an input terminal 38 of a receiving section 16 and an output terminal 40 of a transmitting section 20, and during self-diagnosis, in a control circuit 22, local signals 52 and 66 each having a local frequency (f<SB>TX</SB>(=f<SB>RX</SB>)) in transmission are generated. A control signal 72 is formed which has a frequency (f<SB>IF</SB>) represented by the local signal 66 for transmission (f<SB>TX</SB>) and the local signal 52 for reception (f<SB>RX</SB>-f<SB>IF</SB>); the generated control signal 72 is supplied to the loop-back switch 32, the loop-back switch 32 is turned on; and a difference, being generated in loop-back, between the transmission frequency and the reception frequency is eliminated. <P>COPYRIGHT: (C)2009,JPO&INPIT |
