Title:
通信装置、及び、電子料金収受システム
Document Type and Number:
Japanese Patent JP7285801
Kind Code:
B2
Abstract:
To provide a communication device capable of preventing, multi-pass by receiving radio waves from ETC on-board units located in a communication area while blocking radio waves from ETC on-board units located outside the communication area.SOLUTION: A communication device 100 includes a radome 200 and an antenna 310. The radome 200 has a first transmissive layer 210 and a second transmissive layer 220, and a dielectric layer 230. The first transmissive layer 210 is positioned at a surface of the dielectric layer 230 and allows electromagnetic waves whose frequency is a transmission frequency to be transmitted as a first layer transmitted wave but does not transmit electromagnetic waves whose frequency is different from the transmitted frequency. The second transmissive layer 220 is positioned at a rear side of the dielectric layer 230 and transmits the first layer transmitted wave as the second layer transmitted wave when an angle of incidence of the first layer transmitted wave on the first transmissive layer 210 falls within the second layer transmission range but does not transmit through the first transmissive layer when the angle of incidence on the first transmissive layer 210 is out of the transmission range of the second layer.SELECTED DRAWING: Figure 1
Inventors:
Ryosuke Tani
Application Number:
JP2020073464A
Publication Date:
June 02, 2023
Filing Date:
April 16, 2020
Export Citation:
Assignee:
Mitsubishi Electric Corporation
International Classes:
H01Q15/00; G07B15/00; G08G1/09; H01Q1/42; H01Q15/14
Domestic Patent References:
| JP10507617A |
Foreign References:
| US20130222200 | ||||
| US20140118217 | ||||
| WO2019142677A1 |
Attorney, Agent or Firm:
Patent Attorney Corporation Cross Border Patent Office