AN4148

An overview of ARIB STD-T93 regulation

Doc ID 023517 Rev 1

3/13

1

An overview of ARIB STD-T93 regulation

The ARIB STD-T93 standard provides for telemetry radio equipment designed to

automatically indicate and/or record the results obtained by measuring instruments located

remotely; telecontrol radio equipment for transmission of signals to activate, change or

deactivate the functions of devices located remotely by means of radio waves; data

transmission radio equipment intended for the transmission of information to be processed

primarily by machines, or of previously processed information that uses the frequency of

315 MHz. Expected application is air pressure monitoring equipment for tire and keyless

entry systems for automotive. Audio and sound data is eliminated from this regulation.

The operating frequency band is defined as above 312 MHz to below 315.25 MHz. The

antenna power for frequencies above 312 MHz and below 315.25 MHz must be below 25

µW (- 16 dBm) EIRP (equivalent isotropically radiated power). Also, antenna power (EIRP)

shall be below 205 uW (- 6.9 dBm) when the center of the frequency band added deviation

of frequency to occupied frequency band is between 312 MHz and 315.05 MHz.

There are no specific requirements for the modulation method, modulation rate, frequency

deviation, coding type, and adjacent channel leakage power.

The permissible value for an occupied bandwidth (the bandwidth such that the mean power

radiated below its lower frequency limit and above its upper frequency limit are each equal

to 0.5% of the total mean power radiated by a given emission) shall be 1 MHz.

“Spurious emission” refers to the emission on a frequency or frequencies which are outside

the permitted bandwidth and the level of which may be reduced without affecting the

corresponding transmission of information, including a high harmonic emission, a low

harmonic emission, a parasitic emission and an intermodulation product, but excluding an

out-of-band emission.

“Out-of-band emission” refers to the emission which results from the modulation process on

a frequency or frequencies outside the permitted bandwidth.

“Unwanted emission” refers to the emission consisting of the spurious emission and the out-

of-band emission.

“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. Permissible value of the unwanted emission intensity is shown in

Table 1.

For the receiver part, a conducted spurious component is defined. Permissible value of the

receiver conducting spurious components is defined in

Table 2.