| 摘要 |
PURPOSE:To maintain a circuit even if an obstacle is interposed between antennas, in case of a communication between buildings, etc., by providing a sub- antenna and a passive reflector in each front of opposed main antennas, and providing a level difference between the radio wave concerned and a radio wave of a direct propagation path. CONSTITUTION:A direct route 19 and a detour route 21 for propagating a radio wave are formed by main antennas 11, 12, sub-antennas 13, 14, and passive reflectors 15, 16 in buildings A, B. In this case, a constitution of each sub-antenna and each passive reflector and each propagation route length are selected so that a radio wave of the detour route becomes weaker enough then that of the direct route. Also, for instance, when a gondola 23 cuts off the direct route 19, the radio wave propagation is executed by only the detour route 21. In this case, a receiving electric field drops comparing with the case of the direct route, but when a transmitting power and a receiving gain are made to have allowance, the circuit can be maintained by only the detour route. |
