§ 25.281   Transmitter identification requirements for video uplink
transmissions.

   (a) Earth-to-space transmissions carrying video information with analog
   modulation must be identified through use of an Automatic Transmitter
   Identification System (ATIS) with an analog identifier or a direct
   sequence spread spectrum signal.

   (1) Use of an analog identifier must be in accordance with the
   following requirements:

   (i) The ATIS signal must be a separate subcarrier that is automatically
   activated whenever any radio frequency signal is transmitted.

   (ii) The ATIS message must continuously repeat.

   (iii) The ATIS subcarrier signal must be generated at a frequency of
   7.1 MHz ±25 kHz and modulate the uplink radio frequency carrier at a
   level no less than −26 dB (referenced to the unmodulated carrier).

   (iv) ATIS subcarrier deviation must not exceed 25 kHz.

   (v) The ATIS message protocol must be International Morse Code keyed by
   a 1200 Hz ±800 Hz tone representing a mark and a message rate of 15 to
   25 words per minute. The tone must frequency-modulate the subcarrier
   signal with the ATIS message.

   (vi) The ATIS message must include the FCC-assigned call sign of the
   transmitting earth station, a telephone number providing immediate
   access to personnel capable of resolving interference or coordination
   problems, and a unique serial number of ten or more digits programmed
   into the ATIS message in a permanent manner so that it cannot be
   readily changed by the operator on duty. Additional information may be
   included in the ATIS data stream provided the total ATIS message length
   does not exceed 30 seconds.

   (2) Use of a direct sequence spread spectrum ATIS signal must be in
   accordance with the requirements in paragraphs (b)(1) and (2) of this
   section.

   (b) As of September 3, 2017, transmissions of fixed-frequency,
   digitally modulated video signals with a symbol rate of 128,000/s or
   more from a temporary-fixed earth station must be identified through
   use of an ATIS in accordance with the requirements that follow.

   (1) The ATIS message must be modulated onto a direct sequence spread
   spectrum signal in accordance with the DVB-CID standard, ETSI TS 103
   129 V1.1.2 (2014-03) (incorporated by reference, see § 25.108).

   (2) The ATIS message must continuously repeat.

   Note 1 to paragraph (b): Paragraph (b) is waived for earth stations
   using modulators manufactured before August 1, 2017, that cannot be
   made compliant with the DVB-CID standard by a software upgrade.

   (c) ATIS equipment must be integrated into the uplink transmitter chain
   with a method that cannot easily be defeated.

   [ 79 FR 8325 , Feb. 12, 2014;  81 FR 33601 , May 31, 2016, as amended at  82 FR 40494 , Aug. 25, 2017]

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