AN4174

An overview of the ARIB STD-T67 standard

Doc ID 023728 Rev 1

5/21

Unwanted emission refers to the emissions made up of the spurious emission and the out-

of-band emission.

The permissible value of the unwanted emission intensity refers to the permissible value

defined according to the mean power of unwanted emissions of each modulated frequency

supplied to the feeder. The permissible value of the unwanted emission intensity is 2.5 µW (-

26 dBm) or less, as measured in the average power.

For the receiver, the following parameters are defined.

The reference sensitivity (the necessary receiver input voltage in which the output bit error

rate of the device is 1 x 10-2 when the desired wave modulated is applied) is 2 µV (-101

dBm on 50 ohm) or less for receivers with channel intervals of 12.5 kHz and 25 kHz, and 2.8

µV (-98 dBm on 50

Ω) or less for receivers with channel interval of 50 kHz.

The spurious response at effective selectivity (the ratio of the jamming wave input voltage to

the encoding reference sensitivity as the output bit error rate of the device becomes 1 x 10-

2 when an un-modulated jamming wave is applied in a state in which a desired wave input

voltage 3 dB higher than the encoding reference sensitivity is applied) is 40 dB or more.

The adjacent channel selectivity at effective selectivity (the ratio of the jamming wave input

voltage to the encoding reference sensitivity as the output bit error rate of the device

pseudo noise with a code length of 32767 bits and is 12.5 kHz or 25 kHz in distance from

the desired wave is applied to a device with channel interval of 12.5 kHz or 25 kHz,

respectively, in a state in which the desired wave input voltage 3 dB higher than the

encoding reference sensitivity is applied) is 30 dB or more.

stringent requirement, a TCXO is necessary to meet the frequency tolerance requirement.

The limit of the secondary radiated emission from the receiving equipment is, in terms of the

power of a dummy antenna circuit that has the same electrical constant as the receiving

antenna, 4 nW (-54 dBm) or lower.

Table 1.

Communication method, operating frequencies and antenna power

Communication method

Operating frequency band

[MHz]

Antenna

power [W]

Transmission time restriction

One-way communication,

simplex operation or

broadcast communication

426.0250 - 426.1375

(12.5 kHz interval)

0.001 or less

TCT: 40 sec, TQT: 2 sec

(Telemetry, data transmission)

TCT: 5 sec, TQT: 2 sec

(Telecontrol, data transmission)

426.0375 - 426.1125

(25 kHz interval)

TCT: 40 sec, TQT: 2 sec

(Telemetry, data transmission)

TCT: 5 sec, TQT: 2 sec

(Telecontrol, data transmission)

One-way communication,

simplex operation or

broadcast communication

429.1750 - 429.2375

(12.5 kHz interval)

0.01 or less

TCT: 40 sec, TQT: 2 sec

429.2500 - 429.7375

(12.5 kHz interval)

Continuous transmission

(intermittent communication possible)