| 摘要 |
PROBLEM TO BE SOLVED: To provide a receiver which can simplify an arrangement of an analog circuit, realize downsizing of the receiver and low power consumption, and optionally change a receiving communication system. SOLUTION: A receiver is provided with a low noise amplifier 2 which amplifies signals of a plurality of communication systems received by an antenna 1, local oscillation sources 3a-3c which output local oscillation waves, a mixer 4 which generates a mixing wave of the signals of the communication systems and the local oscillation waves to be outputted as an IF signal, a low-pass filter 5 which removes unnecessary waves, a variable gain amplifier 6 which amplifies the IF signal to a predetermined level, an AD converter 7 which converts a signal into a digital signal, band-pass filters 8a-8c which filter signals of a predetermined communication system, band-pass filters 9a-9c which filter a desired signal within the communication system, and a decoding and controlling circuit 10 which decodes the desired signal, where a frequency of the local oscillation waves is set so that the mixing wave may be arranged adjacent on a frequency axis. COPYRIGHT: (C)2005,JPO&NCIPI
|
