| 摘要 |
<p>A train detecting method highly resistant to noise for detecting a train according to presence/absence of demodulation because of decrease of the level of the received signal due to axel short circuit so as to make a train detection by using a frequency-modulated train detecting signal, wherein before the frequency-dependent demodulation a gain processing for amplifying the amplitude of the signal, a limiter processing for restricting the amplitude of the output signal of the gain processing to a certain level, and a filter processing for eliminating harmonics produced because of the limiter processing are combinedly performed to arbitrarily set the lower limit of the level of the demodulatable signal by means of the gain, thus arbitrarily setting the threshold of train detection.</p> |
