| 摘要 |
PURPOSE:To constitute the protection radio system used for countermeasuring of train protection simply and inexpensively. CONSTITUTION:A relay station of a train radio system used for communication between a train and a ground station is provided with a branching filter 35, a frequency mixer 36, a signal output device 37, a modulator 38 and a directional coupler 40. A protection alarm signal is given to the frequency mixer 36 via an LCX 2B, a distributer 39 and the branching filter 35. The modulator 38 outputs a modulation wave modulated y a relay station identification signal outputted from the signal output device 37. The frequency mixer 36 mixes the protection alarm signal and the modulation wave and sends the result to a base station via the directional coupler and an amplifier 34 or the like. |
