Sec.  15.245   Operation within the bands 902–928 MHz, 2435–2465 MHz, 5785–5815
MHz, 10500–10550 MHz, and 24075–24175 MHz.

   (a) Operation under the provisions of this section is limited to intentional
   radiators used as field disturbance sensors, excluding perimeter protection
   systems.

   (b) The field strength of emissions from intentional radiators operated
   within these frequency bands shall comply with the following:
   Fundamental frequency (MHz) Field strength of fundamental (millivolts/meter)
   Field strength of harmonics (millivolts/meter)
   902–928 500 1.6
   2435–2465 500 1.6
   5785–5815 500 1.6
   10500–10550 2500 25.0
   24075–24175 2500 25.0

   (1) Regardless of the limits shown in the above table, harmonic emissions in
   the restricted bands below 17.7 GHz, as specified in  Sec. 15.205, shall not
   exceed the field strength limits shown in  Sec. 15.209. Harmonic emissions in the
   restricted bands at and above 17.7 GHz shall not exceed the following field
   strength limits:

   (i)  For  the  second and third harmonics of field disturbance sensors
   operating  in the 24075–24175 MHz band and for other field disturbance
   sensors designed for use only within a building or to open building doors,
   25.0 mV/m.

   (ii) For all other field disturbance sensors, 7.5 mV/m.

   (iii) Field disturbance sensors designed to be used in motor vehicles or
   aircraft must include features to prevent continuous operation unless their
   emissions in the restricted bands, other than the second and third harmonics
   from devices operating in the 24075–24175 MHz band, fully comply with the
   limits given in  Sec. 15.209. Continuous operation of field disturbance sensors
   designed to be used in farm equipment, vehicles such as fork lifts that are
   intended primarily for use indoors or for very specialized operations, or
   railroad locomotives, railroad cars and other equipment which travels on
   fixed tracks is permitted. A field disturbance sensor will be considered not
   to be operating in a continuous mode if its operation is limited to specific
   activities of limited duration (e.g., putting a vehicle into reverse gear,
   activating a turn signal, etc.).

   (2) Field strength limits are specified at a distance of 3 meters.

   (3) Emissions radiated outside of the specified frequency bands, except for
   harmonics, shall be attenuated by at least 50 dB below the level of the
   fundamental or to the general radiated emission limits in  Sec. 15.209, whichever
   is the lesser attenuation.

   (4) The emission limits shown above are based on measurement instrumentation
   employing an average detector. The provisions in  Sec. 15.35 for limiting peak
   emissions apply.

   [ 54 FR 17714 , Apr. 25, 1989, as amended at  55 FR 46792 , Nov. 7, 1990;  61 FR 42558 , Aug. 16, 1996;  68 FR 68547 , Dec. 9, 2003]