ARIB STD-T71
ARIB STD-T71 defines the technical requirements for wireless LAN devices operating in the 5 GHz band in Japan. The standard covers → Spurious Emission limits, → Dynamic Frequency Selection (DFS), and power restrictions. It serves as the regulatory basis for certifying 5 GHz Wi-Fi equipment under the Japanese Radio Law.
Scope and Application
The standard applies to two categories of WLAN equipment:
5 GHz Radio Access Systems (e.g. enterprise-grade outdoor access points)
Low-Power Data Communication Systems (e.g. consumer Wi-Fi routers, laptops)
It supports IEEE 802.11a/n/ac (Wi-Fi 5 and early Wi-Fi 6). Devices using Wi-Fi 6E (6 GHz) are not covered under this standard.
Frequency Bands and DFS Requirements
The following bands are defined under ARIB STD-T71 with associated use conditions and restrictions:
| Band | Details |
|---|---|
| 4.9 GHz Band |
Range: 4,900 - 4,990 MHz Applications: Public Safety, Emergency Services Restrictions: Special authorization required |
| 5.2 GHz Band |
Range: 5,150 - 5,250 MHz Applications: Indoor WLAN (802.11a/n/ac/ax) Restrictions: Indoor use only |
| 5.3 GHz Band |
Range: 5,250 - 5,350 MHz Applications: Indoor WLAN with DFS Restrictions: Indoor use only + DFS required |
| 5.6 GHz Band |
Range: 5,470 - 5,725 MHz Applications: Indoor/Outdoor WLAN Restrictions: DFS required |
| Frequency Band | Range (MHz) | Applications | Restrictions |
|---|---|---|---|
| 4.9 GHz Band | 4,900 - 4,990 | Public Safety, Emergency Services | Special authorization required |
| 5.2 GHz Band | 5,150 - 5,250 | Indoor WLAN (802.11a/n/ac/ax) | Indoor use only |
| 5.3 GHz Band | 5,250 - 5,350 | Indoor WLAN with DFS | Indoor use only + DFS required |
| 5.6 GHz Band | 5,470 - 5,725 | Indoor/Outdoor WLAN | DFS required |
DFS is mandatory for devices operating in the 5.3 and 5.6 GHz bands. Key parameters include:
Channel Availability Check: 60 s before transmission
In-Service Monitoring: Continuous radar detection
Channel Move Time: Max. 10 s
Non-Occupancy Period: 30 min after radar detection
Power Limits
5.6 GHz: Maximum EIRP 1 W (30 dBm) – DFS compliance required
Certification and Labeling
Devices must undergo RCB certification and comply with MIC technical regulations. Certified products must display:
The Giteki mark with certification number
The following indoor-use label (if using 5.2/5.3 GHz):
「電波法により5.2/5.3 GHz帯は屋内使用に限ります」
("5.2/5.3 GHz band is restricted to indoor use due to the Radio Law.")
For support with testing and approval, see our → MIC Certification Services.
Note
A comprehensive overview of device categories, certification process, and Giteki marking can be found in the guide → MIC Requirements – Overview.
Further Reading & Official Resources
Official ARIB Standard
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ARIB STD-T71 – 5 GHz-band WLAN equipment for radio access and low-power data communication systems.
This is a curated selection of key sources. For full and up-to-date regulatory documentation, please refer to the official portals of the relevant authorities. All references were verified as of July 2025.