§ 22.917   Emission limitations for cellular equipment.

   The rules in this section govern the spectral characteristics of
   emissions in the Cellular Radiotelephone Service.

   (a) Out of band emissions. The power of any emission outside of the
   authorized operating frequency ranges must be attenuated below the
   transmitting power (P) by a factor of at least 43 + 10 log(P) dB.

   (b) Measurement procedure. Compliance with these rules is based on the
   use of measurement instrumentation employing a reference bandwidth as
   follows:

   (1) In the spectrum below 1 GHz, instrumentation should employ a
   reference bandwidth of 100 kHz or greater. In the 1 MHz bands
   immediately outside and adjacent to the frequency block, a resolution
   bandwidth of at least one percent of the emission bandwidth of the
   fundamental emission of the transmitter may be employed. A narrower
   resolution bandwidth is permitted in all cases to improve measurement
   accuracy, provided that the measured power is integrated over the full
   required reference bandwidth (i.e., 100 kHz or 1 percent of emission
   bandwidth, as specified). The emission bandwidth is defined as the
   width of the signal between two points, one below the carrier center
   frequency and one above the carrier center frequency, outside of which
   all emissions are attenuated at least 26 dB below the transmitter
   power.

   (2) In the spectrum above 1 GHz, instrumentation should employ a
   reference bandwidth of 1 MHz.

   (c) Alternative out of band emission limit. Licensees in this service
   may establish an alternative out of band emission limit to be used at
   specified band edge(s) in specified geographical areas, in lieu of that
   set forth in this section, pursuant to a private contractual
   arrangement of all affected licensees and applicants. In this event,
   each party to such contract shall maintain a copy of the contract in
   their station files and disclose it to prospective assignees or
   transferees and, upon request, to the FCC.

   (d) Interference caused by out of band emissions. If any emission from
   a transmitter operating in this service results in interference to
   users of another radio service, the FCC may require a greater
   attenuation of that emission than specified in this section.

   [ 67 FR 77191 , Dec. 17, 2002, as amended at  82 FR 17583 , Apr. 12, 2017]

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