The Ministry of Internal Affairs and Communications of Japan published the Ministerial Ordinance Partially Revising the Regulations for the Enforcement of the Radio Law (2020 MIC Ordinance No. 59) recently.
The authority issued the regulation related to the currently operational WLAN frequency bands. The interior of the car has been added as a location where it can be used as a low power data communication system in the 5150MHz to 5250MHz band.
The main technical requirements for 5.2 GHz band in-vehicle WLAN system are 40mW EIRP for maximum output power. WLAN devices installed in vehicles may use the 5150-5250 MHz frequency range.
The Ministry of Internal Affairs and Communications has also added the system concerning the introduction of 6GHz band of WLAN. A low-power data communication system is defined by a new frequency band (5925MHz6425MHz).A radio channel that can be used only indoors (equivalent to a maximum EIRP of 200mW), as well as equivalent to a maximum EIRP of 25mW).
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