| 摘要 |
PROBLEM TO BE SOLVED: To enable the simple adjustment of the radiation direction of a radio wave by remote operation after the installation of an antenna device in antenna devices for radio communication with RFID tags and the like.SOLUTION: An antenna device 2 comprises two antenna units 10, 20 arranged with a prescribed space apart so that their radiation directions are the same. Output from the respective antenna units 10, 20 are combined by a micro-strip line formed on a circuit board 30. The micro-strip line combines the output from the respective antenna units 10, 20 in phase, but a variable phase shifter is provided at a part of a signal path from the antenna unit 10, and adjusting the amount of phase shift by the variable phase shifter allows the radiation direction of a radio wave of the antenna device 2 to be controlled. The adjustment of the radiation direction can be performed using a mobile terminal by providing a radio communication module in the antenna device 2.SELECTED DRAWING: Figure 2 |
