| 摘要 |
<p>Distance measuring equipment in which the configuration and control of an RF circuit and signal processing circuit are simplified. Distance measuring equipment (1) comprises an RF circuit (2) including a local oscillator (21), a transmitting antenna (22), a receiving antenna (23), and a mixer (24) and a signal processing circuit (3) including an FFT computation section (31), a database section (32), and a comparison judging section (33). The local oscillator (21) generates a transmitting signal (St) having a frequency varying periodically depending on the phase difference between the transmitting signal (St) and a receiving signal (Sr). The mixer (24) generates an IF signal (Sif) having a frequency with the phase difference between the transmitting signal (St) and the receiving signal (Sr). The FFT computation section (31) of the signal processing circuit (3) performs the fast Fourier transform of the IF signal (Sif) and computes the ratio (V) of a double harmonic component to a fundamental wave component. The comparison judging section (33) reads data (D) having the ratio closest to the ratio (V) from the FFT computing section (31) from a database section (32) and obtains a distance (L) written to the data (D).</p> |
