§  22.970   Unacceptable interference to part 90 non-cellular 800 MHz
licensees from cellular radiotelephone or part 90-800 MHz cellular systems.

   (a) Definition. Except as provided in 47 CFR 90.617(k), unacceptable
   interference to non-cellular part 90 licensees in the 800 MHz band from
   cellular radiotelephone or part 90-800 MHz cellular systems will be
   deemed to occur when the below conditions are met:

   (1) A transceiver at a site at which interference is encountered:

   (i) Is in good repair and operating condition, and is receiving:

   (A) A median desired signal of −104 dBm or higher, as measured at the
   R.F. input of the receiver of a mobile unit; or

   (B) A median desired signal of −101 dBm or higher, as measured at the
   R.F. input of the receiver of a portable i.e. hand-held unit; and,
   either

   (ii) Is a voice transceiver:

   (A) With manufacturer published performance specifications for the
   receiver section of the transceiver equal to, or exceeding, the minimum
   standards set out in paragraph (b) of this section, below; and;

   (B) Receiving an undesired signal or signals which cause the measured
   Carrier to Noise plus interference (C/(I+N)) ratio of the receiver
   section of said transceiver to be less than 20 dB, or,

   (iii) Is a non-voice transceiver receiving an undesired signal or
   signals which cause the measured bit error rate (BER) (or some
   comparable specification) of the receiver section of said transceiver
   to be more than the value reasonably designated by the manufacturer.

   (2) Provided, however, that if the receiver section of the mobile or
   portable voice transceiver does not conform to the standards set out in
   paragraph (b) of this section, then that transceiver shall be deemed
   subject to unacceptable interference only at sites where the median
   desired signal satisfies the applicable threshold measured signal power
   in paragraph (a)(1)(i) of this section after an upward adjustment to
   account for the difference in receiver section performance. The upward
   adjustment shall be equal to the increase in the desired signal
   required to restore the receiver section of the subject transceiver to
   the 20 dB C/(I+N) ratio of paragraph (a)(1)(ii)(B) of this section. The
   adjusted threshold levels shall then define the minimum measured signal
   power(s) in lieu of paragraphs (a)(1)(i) of this section at which the
   licensee using such non-compliant transceiver is entitled to
   interference protection.

   (b) Minimum receiver requirements . Voice transceivers capable of
   operating in the 806-824 MHz portion of the 800 MHz band shall have the
   following minimum performance specifications in order for the system in
   which such transceivers are used to claim entitlement to full
   protection against unacceptable interference (See paragraph (a) (2) of
   this section).

   (1) Voice units intended for mobile use: 75 dB intermodulation
   rejection ratio; 75 dB adjacent channel rejection ratio; −116 dBm
   reference sensitivity.

   (2) Voice units intended for portable use: 70 dB intermodulation
   rejection ratio; 70 dB adjacent channel rejection ratio; −116 dBm
   reference sensitivity.

   [ 69 FR 67834 , Nov. 22, 2004, as amended at  70 FR 76707 , Dec. 28, 2005]

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