ARIB STD-T91
-22-
Annex 3 Design Guidelines for UWB Radio Equipment
1 Design Guideline for the Protection of Broadcast Receiver
1.1 Lowered Permissible Levels of Unwanted Emission Intensity for the Protection of Broadcast
Receivers
Permissible values for unwanted emission intensity provided in ARIB STD-T91 are set lower
than those for unwanted emission intensity for other popular radio equipment such as a land
mobile station for mobile wireless communications (mobile phone), low power data
communications radio equipment (wireless LAN) and radio frequency identification (RFID).
Therefore, UWB (ultra-wideband) radio systems may not immediately cause interference with
other radio equipment such as broadcast receivers. However, if the radio equipment of the radio
station of UWB radio systems (hereinafter referred to as “UWB radio equipment”) is used in a
very close neighborhood of a broadcast receiver, and the level of broadcast emission is near the
receiver sensitivity limit , it is necessary to further lower the unwanted emission intensity of
the specified frequency below those specified in ARIB STD-T91 so as not to cause interference
with broadcast receivers. For this reason, the UWB radio equipment should be designed with
due consideration of permissible values for unwanted emission intensity that protects
broadcast receivers as shown in Table A3-1.In case permissible values for unwanted emission
intensity of the frequency band are not shown in Table A3-1, then ARIB STD-T91 shall apply.
Table A3-1 Permissible values for unwanted emission intensity for protecting broadcast receiver
Permissible values unwanted
emission intensity
Frequency band
Interfered system
Average power at any 1 MHz
bandwidth (e.i.r.p.)
From 170 MHz to 222 MHz
Terrestrial broadcasting
(VHF 4-12 ch)
-114.7 dBm or less
From 470 MHz to 770 MHz
Terrestrial broadcasting
(UHF 13-62 ch)
-106.1 dBm or less
From 2630 MHz to 2655 MHz Mobile broadcasting
-111.7 dBm or less
Note: e.i.r.p.: Effective Isotropic Radiated Power