| 摘要 |
<p>Very long distance navigation is performed using radio stations to transmit modulated or unmodulated signals to generate positioning lines of signals. This permits control of moving traffic and acts as an anticollision equipment. Four radio transmitters at various locations emit modulated or unmodulated carriers which are stable. The signal is received on board a vehicle by receivers (9) in which the signals are amplified without distortion. The output of each receiver is applied to a discriminator (7) for phase and frequency comparison with a multiplied (6) value from a frequency generator (5) with a controllable phase. The error signal from the discriminator corrects the phasing of the generator. A phase shifter (8) allows the indications at the origin on the indicators to be made to coincide with those representing the present location.</p> |
