Scope and Impact of Regulation
The regulation primarily involves amendments to the Enforcement Regulations of the Radio Act and the Radio Equipment Regulations (MIC Ordinance No. 78). It focuses on the introduction and technical refinement of Wireless Power Transmission (WPT) systems and Specified Low Power Radio Stations. The impact is significant for manufacturers of RFID and WPT equipment, as it defines new technical requirements for interference prevention, human exposure limits (SAR), and frequency allocation in the 900 MHz band.
Permitted Radio Bands and Technical Specifications
The regulation details specific frequency ranges and associated technical parameters for mobile identification and wireless power transmission:
Frequency Ranges: 916.7 MHz to 920.9 MHz and 920.5 MHz to 923.5 MHz.
WPT Designated Center Frequencies: 918 MHz and 919.2 MHz.
Channel Bandwidth: 200 kHz unit channels.
Maximum Simultaneous Channels: Limited to 5 channels.
Antenna Power: Generally limited to 0.25W or less. For certain configurations, equivalent isotropically radiated power (EIRP) must be 0.5W or less.
Carrier Sense Requirements: Systems must implement carrier sense with a sensitivity threshold of -74 dBm (at the feeder input) to prevent interference with other radio stations.
Exemptions and Restrictions
The regulation imposes strict operational environments for Wireless Power Transmission (WPT) devices:
Operational Space: WPT systems must operate within indoor environments or enclosed spaces where it is clear that radio wave strength is sufficiently attenuated by walls or partitions (including windows).
Location Restrictions: Certain WPT stations are restricted to operation in underground areas or on the first floor above ground.
Containment: Radio equipment must generally be housed in a single integrated cabinet that cannot be easily opened.
In-Country Testing and Conformity Assessment
The regulation modifies the "Ordinance concerning Technical Regulations Conformity Certification of Specified Radio Equipment" to include WPT-specific testing procedures. Manufacturers must undergo certification based on the following standards:
Technical Parameter Testing: Verification of frequency accuracy, occupied bandwidth, spurious emission intensity, and antenna power.
Human Exposure (SAR) Requirements: For devices used within 20cm of the human body (excluding the head and hands), Specific Absorption Rate (SAR) testing is mandatory.
SAR Limits: The limit is set at 2W/kg for the body (averaged over 10g of tissue) and 4W/kg for the limbs.
Transmission Time Limits: Equipment must include a device that automatically limits transmission duration and enforces a mandatory pause time (suspension) between transmissions.
Labeling Requirements
Devices falling under this regulation are classified as "Specified Radio Equipment." They must comply with the standard labeling requirements for Technical Regulations Conformity Certification (GITEKI) in Japan. This involves the application of the conformity mark and the associated certification number once the device has passed assessment by a Registered Certification Body (RCB).
Modification of Existing Regulations
This regulation acts as an amending ordinance that modifies several foundational radio regulations in Japan, including:
Regulations for Enforcement of the Radio Act (電波法施行規則, Radio Regulatory Commission Rules No. 14 of 1950).
Radio Equipment Regulations (無線設備規則, Radio Regulatory Commission Rules No. 18 of 1950).
Ordinance concerning Technical Regulations Conformity Certification of Specified Radio Equipment (特定無線設備の技術基準適合証明等に関する規則, MOPT Ordinance No. 37 of 1981).
MIC Notifications: It specifically modifies MIC Notification No. 42 (Use/Frequencies for Low Power Stations) and MIC Notification No. 49 (Containment and Carrier Sense Conditions).
