The O utline of Proposed Amendment to M inisterial O rdinance  
 
１ Item 
Partial  amendment of Regulations for Enforcement of the Radio Law  
 
２ Amendment to ministerial ordinance  
Regulations for Enforcement of the Radio Low  
    Regulations for Radio Equipment  
    Concerning Technical Regulations Conformity Certification of Specified  Radio Equipment  
 
３ Reason s for amendment  
Expanding sensor network increases the usage s of 920MHz  band low power wireless 
system which include the low speed radio communication using f or detection sensors.  
Based on these usages, technical regulations such as the channel use, transmission 
time and antenna gain are required amendment to promote the development of the 
radio systems and services.  
The reason for this amendment is to expand t he new purpose of use of the 920MHz 
band low power wireless system and to meet demands for heavily use of radio 
frequency.  
 
 
４ Outline of the amendment  
 
Technical requirements of radio equipment  (Red underlined character is 
amended)  
○Technical requirements of Passive tag system 【Amended parts】 
 1W RFID system  250mW  RFID system  
Radio type  No regulation  
Power  1W or less  250mW  or less 
The power can exceed 250mW  up to 
500mW when the radio equipment is 
inside one component  which cannot be 
opened easily and EIRP  (Effective 
Isotropically Radiated Power ) is less 
than 27dBm.   [様式Ｂ]   
Antenna gain  6dBi  or less  3dBi or less  
The antenna gain can e xceed 3dBi  up to 
27dBm  EIRP . 
Carrier sense 
level  -74dBm  -74dBm（ -64dBm when power  is less 
than 10mW .） 
In case of the power exceed 250mW, 
make carrier sense level decrease in dB  
which  exceed ed power beyond 250mW.  
 
○Technical requirements of Active tag system 【Amended part】  
 250mW  system  20mW  system  1mW  system  
Frequency  
tolerance  ±20×10-6 or less  
The frequency tolerance can exceed above value within the assigned frequency band 
when using one unit channel.  
Power  250mW  or less  20mW  or less  
The power can exceed 
20mW up to 25 0mW when 
the radio equipment is 
inside one  component  
which cannot be opened 
easily and EIRP  is less 
than 16 dBm.   1mW  or less  
The power can exceed 
1mW up to 25 0mW when 
the radio equipment is 
inside one component  
which cannot be opened 
easily and EIRP  is less 
than 3 dBm.   
Antenna gain  3dBi  or less  
The antenna gain can 
exceed 3dBi up to 27dBm 
EI R P.  3dBi  or less  
The antenna gain can 
exceed 3dBi up to 16dBm 
EI R P.  3dBi  or less  
The antenna gain can 
exceed 3dBi up to 3dBm  
EIRP . 
Transmission 
time  [Carrier sense time : 5ms 
or more ] 
Sending duration : 4s or 
less 
Pause duration : 50ms  or 
more  [Carrier sense time : 5ms 
or more ] 
Sending duration : 4s or 
less 
Pause duration : 50ms or 
more  [Carrier sense : No need ] 
(1) 916-928MHz  
Sending duration : 100ms 
or less , cannot exceed 
3.6s/h.  
Pause duration : 100ms or  
[Carrier sense time : 128μs  
or more]  
Sending duration : 400ms  
or less , cannot exceed 
360s/h.  
Pause duration : 2ms or 
more  
The sending duration can 
be excluded from 360s/h 
limitation for ACK which 
starts within 2ms when  
receiving the request  and 
finishes within 5ms (50ms 
for syste ms using one unit 
channel) when receiving    
the request . [Carrier sense time : 128μs  
or more]  
Sending duration : 400ms  
or less , cannot exceed 
360s/h.  
Pause duration : 2ms or 
more  
*The sending duration can 
be excluded from 360s/h 
limitation  for ACK which 
starts within 2ms when  
receiving the request  and 
finishes within 5ms (50ms 
for systems using one unit 
channel) when receiving 
the request . more  
 
(2) 928.15-929.65MHz  
Sending duration : 50ms or 
less 
Pause duration : 50ms or 
more  
Carrier sense 
level  -80dBm  -80dBm  
In case of the power exceed 
250mW, make c arrier 
sense level decrease in dB 
which exceeded power 
beyond 250mW.  No need  
Identification code 32 bit s or more  which required operations for telecommunication business.  
 
 
５ Proposed dat e of entry into force  
August , 2017