Wireless LAN Outdoor Use

This is a restriction according to the rules stipulated by the law (Radio Law).

Radio laws prohibit outdoor use of the 5.2 GHz and 5.3 GHz bands when using the 5 GHz band.

There are several types of bands in the 5GHz band, and there seems to be a band for outdoor, but the definition of indoor seems to be as follows:

"Indoor" refers to the interior space of a building surrounded by walls on all sides, and inside a station platform, a car, a train, and other vehicles are treated as outdoor

Note:
Use in the 5GHz band|Aterm User's Manual
Wireless LAN 5.2 GHz band (W52) to revise the Radio Law Enforcement Rules for outdoor use

It was fun, so I tried to google it.Apparently, it is regulated by law.
he and
http://kaden-r-han.blog.jp/archives/5GHz.html

There are many legal interpretation problems, but wouldn't it be acceptable if your wifi repeater is installed outdoors in the 5Ghz band?Also, the 5Ghz band is vulnerable to shielding in the 2.4Ghz band. I think it might not be suitable for your use.In any case, I think it would be better to consult a lawyer or other specialist for a strict interpretation of the law.There are a lot of engineers here, but I don't think there are many people who specialize in legal matters...