| 摘要 |
PURPOSE:To make a communication which uses a radio wave in a 50GHz band in a tunnel pit. CONSTITUTION:A communication unit 1 consists of a main body 2 equipped with a conical horn and a Cassegrain antenna 3 and is installed inside and outside the pit by using a fitting member. A two-way type for transmission and reception is used as the communication unit 1. Two communication units 1 and 1 are connected to constitute a repeating device 5. The repeating device 5 is installed at a curved part in the gateway. Communication units 1 are independently installed at the end inside the tunnel pit and the end outside the tunnel pit. A monitor camera V, a machine M for construction, and a telephone set T are connected to the communication unit 1 inside the gateway and a monitor D, a remote controller P, and a telephone set T are connected to the communication unit 1 outside the gateway. The repeating device 5 repeats radio waves in order by the reception of one communication unit 1 and the transmission of the other communication unit 1. Consequently, the radio waves are propagated without irregular reflection on the internal wall. |
