47 CFR 90.361 - Interference from part 15 and Amateur operations.
Operations authorized under parts 15 and 97 of this chapter may not cause harmful interference to LMS systems in the 902-928 MHz band. These operations will not be considered to be causing harmful interference to a multilateration LMS system operating in one of the three EA sub-bands (see § 90.357(a)) if they are non-video links operating in accordance with the provisions of parts 15 or 97 of this chapter and at least one of the following conditions are met:
(a) It is a field disturbance sensor operating under § 15.245 of this chapter and it is not operating in the 904-909.750 or 919.750-928.000 MHz sub-bands; or
(b) It does not employ an outdoor antenna; or
(c) If it does employ an outdoor antenna, then if:
(1) The directional gain of the antenna does not exceed 6 dBi, or if the directional gain of the antenna exceeds 6 dBi, it reduces its transmitter output power below 1 watt by the proportional amount that the directional gain of the antenna exceeds 6 dBi; and
(i) The antenna is 5 meters or less in height above ground; or
(ii) The antenna is more than 5 meters in height above ground but less than or equal to 15 meters in height above ground and either:
(A) Adjusts its transmitter output power below 1 watt by 20 log (h/5) dB, where h is the height above ground of the antenna in meters; or
(B) Is providing the final link for communications of entities eligible under subpart B or C of this part, or is providing the final link for communications of health care providers that serve rural areas, elementary schools, secondary schools or libraries.