§  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
   § 15.205, shall not exceed the field strength limits shown in § 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 § 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 § 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 § 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]