| 摘要 |
<p>PURPOSE: To attain communication with high quality by selecting a 2nd transmission signal subject to spread processing through the use of a 1st transmission signal or a PN code resulting from modulation-processing data to be sent to a ground side and sending the selected signal to the ground so as to combine the spread spectrum(SS) communication excellent in noise resistance and the FSK communication. CONSTITUTION: An on-train transmitter-receiver (b) is provide with a 1st transmission signal generating means 15 applying modulation processing to data to sent to the ground by the FSK or the like to generate a 1st transmission signal, a 2nd transmission signal generating means 11 applying spread processing to the data to be sent to the ground by using a prescribed PN code to generate a 2nd transmission signal, and a transmission means 14 selecting the 1st transmission signal or the 2nd transmission signal and sending the selected signal to the ground. Since two kinds of the transmission equipments adopting the SS communication and the FSK communication are provided to the on-train transmitter-receiver (b) and the signal is sent to the ground, the communication with excellent quality is attained even at a location where transmission environment is insufficient through the use of a same frequency channel.</p> |
