§ 15.709   General technical requirements.

   (a) Power limits for TVBDs. (1) For fixed TVBDs, the maximum power delivered
   to the transmitting antenna shall not exceed one watt per 6 megahertz of
   bandwidth  on  which  the  device operates. The power delivered to the
   transmitting antenna is the maximum conducted output power reduced by the
   signal loss experienced in the cable used to connect the transmitter to the
   transmit antenna. If transmitting antennas of directional gain greater than
   6 dBi are used, the maximum conducted output power shall be reduced by the
   amount in dB that the directional gain of the antenna exceeds 6 dBi.

   (2) For personal/portable TVBDs, the maximum EIRP shall not exceed 100
   milliwatts  (20  dBm) per 6 megahertz of bandwidth on which the device
   operates with the following exceptions; Mode II personal/portable TVBDs that
   do not meet the adjacent channel separation requirements in § 15.712(a) and
   Mode I personal/portable TVBDs that operate on available channels (provided
   by  a  Mode  II TVBD) that do not meet the adjacent channel separation
   requirements of § 15.712(a) are limited to a maximum EIRP of 40 milliwatts
   (16 dBm) per 6 megahertz of bandwidth on which the device operates.

   (3) TVBDs shall incorporate transmit power control to limit their operating
   power to the minimum necessary for successful communication. Applicants for
   equipment certification shall include a description of a device's transmit
   power control feature mechanism.

   (4) Maximum conducted output power is the total transmit power over the
   occupied bandwidth delivered to all antennas and antenna elements averaged
   across  all  symbols in the signaling alphabet when the transmitter is
   operating at its maximum power control level. Power must be summed across
   all antennas and antenna elements. The average must not include any time
   intervals  during which the transmitter is off or is transmitting at a
   reduced power level. If multiple modes of operation are possible (e.g.,
   alternative modulation methods), the maximum conducted output power is the
   highest total transmit power occurring in any mode.

   (5) The power spectral density from the TVBD shall not be greater than the
   following values when measured in any 100 kHz band during any time interval
   of continuous transmission.

   (i) Fixed devices: 12.6 dBm conducted power. If transmitting antennas of
   directional gain greater than 6 dBi are used, this conducted power level
   shall  be reduced by the amount in dB that the directional gain of the
   antenna exceeds 6 dBi.

   (ii) Personal/portable device operating adjacent to occupied TV channels:
   −1.4 dBm EIRP.

   (iii) Sensing-only devices: −0.4 dBm EIRP.

   (iv) All other personal/portable devices: 2.6 dBm EIRP.

   (6) TVBDs shall incorporate adequate security measures to prevent the TVBD
   from  accessing  databases  not approved by the FCC and to ensure that
   unauthorized  parties can not modify the TVBD or configure its control
   features to operate inconsistent with the rules and protection criteria set
   forth in this subpart.

   (b)  Antenna  requirements. (1) All transmit and receive antenna(s) of
   personal/portable devices shall be permanently attached.

   (2) The transmit antenna used with fixed devices may not be more than 30
   meters above the ground. In addition, fixed devices may not be located at
   sites  where the antenna height above average terrain is more than 250
   meters. The HAAT is to be calculated by the TV bands database that the
   device  contacts  for  available channels using computational software
   employing the methodology in § 73.684(d) of this chapter.

   (3) For personal/portable TVBDs operating under § 15.717, the provisions of
   § 15.204(c)(4)  do  not  apply  to an antenna used for transmission and
   reception/spectrum sensing.

   (4) For personal/portable TVBDs operating under § 15.717 that incorporate a
   separate sensing antenna, compliance testing shall be performed using the
   lowest gain antenna for each type of antenna to be certified.

   (c) Emission limits for TVBDs. (1) In the television channels immediately
   adjacent to the channel in which the TVBD is operating, emissions from the
   TVBD shall not exceed the following levels.

   (i) Fixed devices: −42.8 dBm conducted power.

   (ii) Personal/portable device operating adjacent to occupied TV channels:
   −56.8 dBm EIRP.

   (iii) Sensing-only devices: −55.8 dBm EIRP.

   (iv) All other personal/portable devices: −52.8 dBm EIRP.

   (2) Emission measurements in the adjacent channels shall be performed using
   a  minimum resolution bandwidth of 100 kHz with an average detector. A
   narrower resolution bandwidth may be employed near the band edge, when
   necessary, provided the measured energy is integrated to show the total
   power over 100 kHz.

   (3) At frequencies beyond the television channels immediately adjacent to
   the channel in which the TVBD is operating, the radiated emissions from
   TVBDs shall meet the requirements of § 15.209.

   (4) Emissions in the band 602-620 MHz must also comply with the following
   field strength limits at a distance of one meter.
   Frequency
   (MHz) Field strength
   dBµV/meter/120 kHz
         602-607       120-5[F(MHz)-602]
         607-608       95
         608-614       30
         614-615       95
         615-620       120-5[620-F(MHz)]

   (5) TVBDs connected to the AC power line are required to comply with the
   conducted limits set forth in § 15.207.

   (d)  Compliance  with radio frequency exposure requirements. To ensure
   compliance with the Commission's radio frequency exposure requirements in
   § § 1.1307(b),  2.1091  and 2.1093 of this chapter, fixed TVBDs shall be
   accompanied by instructions on measures to take to ensure that persons
   maintain  a distance of at least 40 cm from the device, as well as any
   necessary hardware that may be needed to implement that protection. These
   instructions shall be submitted with the application for certification.
   Personal/portable TVBDs that meet the definition of portable devices under
   § 2.1093 of this chapter and that operate with a source-based time-averaged
   output of less than 20 mW will not be subject to routine evaluation for
   compliance with the radio frequency exposure guidelines, while devices that
   operate with a source-based time-average output power greater than 20 mW
   will be subject to the routine evaluation requirements.

   [ 74 FR 7326 , Feb. 17, 2009, as amended at  75 FR 75836 , Dec. 6, 2010;  77 FR 29245 , May 17, 2012]

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