§ 15.709   General technical requirements.

   (a) Radiated power limits. The maximum white space device EIRP per 6
   MHz shall not exceed the limits of paragraphs (a)(2) through (4) of
   this section.

   (1) General requirements. (i) White space devices may be required to
   operate with less power than the maximum permitted to meet the
   co-channel and adjacent channel separation requirements of § 15.712 of
   this part.

   (ii) Mode I personal/portable devices are limited to 40 mW, if the
   white space device that controls it is limited to 40 mW.

   (2) TV bands and 600 MHz service band. (i) Fixed devices: Up to 4 W (36
   dBm) EIRP, and up to 10 W (40 dBm) EIRP in less congested areas in the
   TV bands and 600 MHz service band at locations where they meet the
   co-channel and adjacent channel separation distances of § § 15.712(a)(2)
   and 15.712(i) of this part, respectively. Operation in the 602-620 MHz
   band is limited to a maximum of 4 W (36 dBm) EIRP.

   (ii) Personal/Portable devices: Up to 100 mW (20 dBm) EIRP.

   (3) 608-614 MHz band (channel 37). Up to 40 mW (16 dBm) EIRP.

   (ii) Personal/Portable devices: Up to 100 mW (20 dBm) EIRP.

   (4) 600 MHz duplex gap and guard bands. Up to 40 mW (16 dBm) EIRP.

   (b) Technical limits—(1) Fixed white space devices. (i) Technical
   limits for fixed white space devices are shown in the table in
   paragraph (b)(1)(iii) of this section and subject to the requirements
   of this section.

   (ii) For operation at EIRP levels of 36 dBm (4,000 mW) or less, fixed
   white space devices may operate at EIRP levels between the values shown
   in the table in paragraph (b)(1)(iii) of this section provided that the
   conducted power and the conducted power spectral density (PSD) limits
   are linearly interpolated between the values shown and the adjacent
   channel emission limit of the higher value shown in the table is met.
   Operation at EIRP levels above 36 dBm (4,000 mW) shall follow the
   requirements for 40 dBm (10,000 mW).

   (iii) The conducted power spectral density from a fixed white space
   device shall not be greater than the values shown in the table in this
   paragraph (b)(1)(iii) when measured in any 100 kHz band during any time
   interval of continuous transmission.

   Table 1 to Paragraph (b)(1)(iii)
   EIRP
   (6 MHz) Conducted power limit
   (6 MHz) Conducted
   PSD limit
   (100 kHz)
   (dBm) Conducted
   adjacent channel
   emission limit
   (100 kHz)
   (dBm)
           16 dBm (40 mW)       10 dBm (10 mW)    −7.4 −62.8
           20 dBm (100 mW)      14 dBm (25 mW)    −3.4 −58.8
           24 dBm (250 mW)      18 dBm (63 mW)     0.6 −54.8
           28 dBm (625 mW)      22 dBm (158 mW)    4.6 −50.8
           32 dBm (1,600 mW)    26 dBm (400 mW)    8.6 −46.8
           36 dBm (4,000 mW)    30 dBm (1,000 mW) 12.6 −42.8
           40 dBm (10,000 mW)   30 dBm (1,000 mW) 12.6 −42.8

   (2) Personal/portable white space devices. (i) Technical limits for
   personal/portable white space devices are shown in the table in
   paragraph (b)(2)(ii) of this section and subject to the requirements of
   this section.

   (ii) The radiated power spectral density from a personal/portable white
   space device shall not be greater than the values shown in the table in
   this paragraph (b)(2)(ii) when measured in any 100 kHz band during any
   time interval of continuous transmission.

   Table 2 to Paragraph (b)(2)(ii)
   EIRP
   (6 MHz) Radiated PSD
   limit EIRP
   (100 kHz)
   (dBm) Radiated adjacent
   channel emission
   limit EIRP
   (100 kHz)
   (dBm)
           16 dBm (40 mW)   −1.4 −56.8
           20 dBm (100 mW)   2.6 −52.8

   (3) Sensing-only devices. Sensing-only white space devices are limited
   to 17 dBm (50 mW) EIRP and are subject to the requirements of this
   paragraph and of § 15.717 of this part.

   (i) Radiated PSD limit: −0.4 dBm EIRP.

   (ii) Adjacent channel emission limit: −55.8 dBm EIRP.

   (c) Conducted power limits. (1) The conducted power, PSD and adjacent
   channel limits for fixed white space devices operating at up to 36 dBm
   (4000 milliwatts) EIRP shown in the table in paragraph (b)(1) of this
   section are based on a maximum transmitting antenna gain of 6 dBi. 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) The conducted power, PSD and adjacent channel limits for fixed
   white space devices operating at greater than 36 dBm (4000 milliwatts)
   EIRP shown in the table in paragraph (b)(1) of this section are based
   on a maximum transmitting antenna gain of 10 dBi. If transmitting
   antennas of directional gain greater than 10 dBi are used, the maximum
   conducted output power shall be reduced by the amount in dB that the
   directional gain of the antenna exceeds 10 dBi.

   (3) 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 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.

   (4) White space devices connected to the AC power line are required to
   comply with the conducted limits set forth in § 15.207.

   (d) Emission limits. (1) The adjacent channel emission limits shown in
   the tables in paragraphs (b)(1) and (2) of this section apply in the
   six megahertz channel immediately adjacent to each white space channel
   or group of contiguous white space channels in which the white space
   device is operating.

   (2) At frequencies beyond the six megahertz channel immediately
   adjacent to each white space channel or group of contiguous white space
   channels in which the white space device is operating the white space
   device shall meet the requirements of § 15.209.

   (3) Emission measurements in the adjacent bands 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.

   (e) Transmit power control. White space devices 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 the device's transmit
   power control feature mechanism.

   (f) Security. White space devices shall incorporate adequate security
   measures to prevent the devices from accessing databases not approved
   by the FCC and to ensure that unauthorized parties cannot modify the
   device or configure its control features to operate in a manner
   inconsistent with the rules and protection criteria set forth in this
   subpart.

   (g) Antenna requirements—(1) Fixed white space devices—(i) Above ground
   level. The transmit antenna height shall not exceed 100 meters above
   ground level in less congested areas or 30 meters above ground level in
   other areas, except that the antenna height may not exceed 10 meters
   above ground level in any area for fixed white space devices operating
   in the TV bands at 40 mW EIRP or less or operating across multiple
   contiguous TV channels at 100 mW EIRP or less.

   (ii) Height above average terrain (HAAT). The transmit antenna shall
   not be located where the height above average terrain is more than 250
   meters. The HAAT is to be calculated by the white space database using
   the methodology in § 73.684(d) of this chapter.

   (2) Personal/portable white space devices. Personal/portable devices
   shall have permanently attached transmit and receive antenna(s).

   (3) Sensing-only white space devices operating under the provisions of
   § 15.717 of this subpart. (i) The provisions of § 15.204(c)(4) do not
   apply to an antenna used for transmission and reception/spectrum
   sensing.

   (ii) Compliance testing for white space devices that incorporate a
   separate sensing antenna shall be performed using the lowest gain
   antenna for each type of antenna to be certified.

   (h) Compliance with radio frequency exposure requirements—(1) Fixed
   white space devices. To ensure compliance with the Commission's radio
   frequency exposure requirements in § § 1.1307(b), 2.1091 and 2.1093 of
   this chapter, fixed white space devices 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.

   (2) Personal/portable white space devices. Personal/portable white
   space devices 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
   in § § 1.1307(b), 2.1091, and 2.1093 of this chapter, while devices that
   operate with a source-based time-average output power greater than 20
   mW will be subject to the routine evaluation requirements.

   [ 80 FR 73070 , Nov. 23, 2015, as amended at  84 FR 34797 , July 19, 2019]

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