Attachment 
1 
 The Outline of Proposed Amendment to Ministerial Ordinance 
 
1. Item 
Partial amendment of Regulations for Radio Equipment 
 
2. Amendment to ministerial ordinance 
Amendment for Radio Equipment 
 
3. Reasons for amendment 
Regarding the existing satellite communication system using L-band 
based on the satellite constellation by non-geostationary satellites, the 
existing satellite operator is planning to upgrade the satellites in order to 
achieve high speed communication, and is also planning to utilize this 
satellite communication system for distress and safety communications of 
ships and aircrafts. 
Responding these new usage needs for“Non-geostationary satellite 
system using advanced L-band”, Japan will formulate the technical 
requirements for implementing this non-geostationary orbit satellite 
system using Advanced L-band. 
 
4. Outline of the amendment Attachment 
2 
 Table 1 Basic technical requirements of radio equipment 
System Advanced L-band non-geostationary system 
Station Class Mobile earth station 
(except for GMDSS) Aircraft earth station Ship earth station 
(for GMDSS) 
General 
condition Appropriate measures shall be taken to prevent inappropriate use for promoting security, 
and to satisfy the Radio-radiation protection guidelines in order to countermeasure effects 
on the human body, etc. 
Frequency band Service link: 
1,618.25-1,626.5MHz 
In operating, Frequency 
band shall comply with the 
results of international 
coordination by the Radio 
Regulations. Service link: 
1,621.35-1,626.5MHz 
In operating, Frequency band shall comply with the results 
of international coordination by the Radio Regulations. 
 
Transmitter 
Frequency 
tolerance 30×10-6 
Antenna power 
tolerance Upper limit 50%, Lower limit 50% 
Tolerance of 
unwanted 
emission 
intensity To meet Radio 
Regulations Appendix 3 
and Recommendation 
ITU-R M.1343 To meet ETSI EN 301 
473 To meet Radio Regulations 
Appendix 3 and 
Recommendation ITU-R 
M.1343 
Power level 
when no carrier 
is transmitting To meet Recommendation 
ITU-R M.1343 To meet ETSI EN 301 
473E To meet Recommendation 
ITU-R M.1343 
Automatic 
radio emission 
stop function To meet Recommendation ITU-R M.1343 
Receiver 
Limit of 
secondary 
radiated 
emissions Same as Power level when no carrier is transmitting 
Antenna 
Minimum 
elevation 
angle of 
transmitting 
antenna To keep at least 3 degrees 
from the horizontal plane To meet Table 2 To keep at least 3 degrees from 
the horizontal plane 
Polarization Right-handed circular polarization 
 
 
 
 Attachment 
3 
 Table 2 Additional technical requirements for aircraft earth stations 
System Aircraft earth station of Advanced L-band non-geostationary system 
Transmitter 
Power handling 
performance To have 20W CW handling performance. For AES3, to design according to the maximum 
number of transmission carriers. 
Antenna 
voltage 
standing wave 
ratio 1.8 : 1 
Equivalent 
isotropic 
radiation power Upper limit 9dBW, lower limit -4dBW of EIRP of one carrier.  
The average EIRP within the transmission burst time shall not exceed 15dBW minus 
antenna gain. 
Power control For AES2 and AES3, to have the ability to control the radiated power level within a 
back-off range of 8 dB and a step size of 1 dB. 
Transmission 
performance Operable at flight speeds below 800 knots (1480 km / h) 
Receiver 
Receive 
sensitivity The allowable noise level shall be as follows. 
Wideband: -124dBm @ 200kHz (desired signal level: -106dBm @ 35kHz)  
Narrow band: -121dBm @ CW (same channel), -106dBm @ CW (adjacent channel), 
-66dBm @ CW (10ch apart)  
Packet error 
rate 1x10-6 
Interference 
elimination Enable to receive and track the satellite downlink signal even under the interference 
signal of -10dBm, in the band of 470MHz to 18,000MHz except for the band of 0.95 × 
1616MHz to 1.05 × 1626.5MHz. 
Enable to reduce the interference signal to a value obtained by linear interpolation from 
-50 dBm to -72 dBm between 0.95 × 1616 MHz and 0.99938 × 1616 MHz, and to a value 
obtained by linear interpolation from -72 dBm to -10 dBm between 1.00062 × 1626.5 
MHz and 1.05 × 1626.5 MHz. 
Enable to receive and track satellite downlink signals in the 1626.5 MHz to 1660.5 MHz 
band, even under -96 dBm CW interference signals, when there is no other AMS (R) S 
device in the same aircraft. 
Enable to receive and track satellite downlink signals in the 1626.5 MHz to 1660.5 MHz 
band, even under -2 dBm CW interference signals, when there is other AMS (R) S device 
in the same aircraft.  
Reception 
performance Operable at flight speeds below 800 knots (1480 km / h) 
Antenna 
Minimum 
elevation angle 
of transmitting 
antenna Satisfying requirements for antenna polarization, antenna gain, and axial ratio in the 
range of elevation angle of 8° to 90°. 
Antenna gain Minimum gain: -2 Weighted dBic、Maximum gain: 3 Weighted dBic 
Axle ratio 2.5dB or lower 
Carrier 
multipath 
difference The decibel difference between the minimum antenna gain at the minimum elevation 
angle and the maximum antenna gain at the same elevation angle below the horizon shall 
be larger than the minimum carrier multipath difference. 
Minimum carrier multipath difference shall be greater than 3dB. 
Type of aircraft earth station 
AES1: Consists of one Short Burst Data (SBD) transceiver and one Passive Low Gain Antenna (LGA) 
AES2: Consists of one or two L-band transceivers and one passive LGA 
AES3: Consists of two or more SBD and / or L-band transceivers and one Passive LGAAttachment 
4 
 Table 3 Additional technical requirements for Ship earth stations 
System Ship earth station of Advanced L-band non-geostationary system (for GMDSS) 
General Condition 
Other 
requirements Required functions, interfaces, identification of ship earth stations, transmission of 
distress alerts/calls, reception of distress, urgency and safety alerts/calls, audible signal 
and visual indications, test facilities, Enhanced Group Call (EGC) communications 
including Maritime Safety Information (MSI), position updating, power and energy 
supply, and antenna locations shall comply with IMO resolution MSC.434 (98). Safety 
precautions and maintenance shall comply with IMO Resolution A.694 (17).Labeling and 
identification shall comply with IMO Resolution MSC.434 (98) and IMO Resolution 
A.694 (17). 
 
5. Proposed date of entry into force 
July, 2020