| 摘要 |
<p>PROBLEM TO BE SOLVED: To disperse the energy of noise and enable the improvement of the sensitivity of reception by providing a digital filter processing part which removes undesired signals and a frequency analysis processing part which analyzes frequencies. SOLUTION: The oscillation output signals of an oscillator 5 are inputted to a PLL(phase lock loop) synthesizer 4 and step recovery diode 9 to become the signals of transmitted waves via the synthesizer 4, and which are transmitted from an antenna 1 via a switch part 3. Reflected radio waves are received by the antenna 1 and inputted to an amplifier 6 via a transmitting/receiving device 2. Then the signals are inputted to a double balance mixer 7. The output signals of the diode 9 are inputted to this mixer 7 to be mixed with the signals of the received waves, the signals of a Doppler frequency are outputted, and inputted to an A/D converter 8 to be converted to digital signals. The converted signals, from which undesired signal components are removed at a digital filter processing part 11, are inputted to a frequency analysis processing part to be converted to the signals of relative speed from the signals of a Doppler frequency.</p> |
