Sec.  90.1215   Power limits.

   The transmitting power of stations operating in the 4940–4990 MHz band must
   not exceed the maximum limits in this section.

   (a) The peak transmit power should not exceed:
   Channel bandwidth
   (MHz) Low power peak transmitter power
   (dBm) High power peak transmitter power
   (dBm)
         1                                   7   20
         5                                  14   27
         10                                 17   30
         15                               18.8 31.8
         20                                 20   33

   High power devices are also limited to a peak power spectral density of 21
   dBm per one MHz. High power devices using channel bandwidths other than
   those listed above are permitted; however, they are limited to a peak power
   spectral density of 21 dBm/MHz. If transmitting antennas of directional gain
   greater than 9 dBi are used, both the peak transmit power and the peak power
   spectral  density should be reduced by the amount in decibels that the
   directional  gain  of  the  antenna exceeds 9 dBi. However, high power
   point-to-point   or  point-to-multipoint  operation  (both  fixed  and
   temporary-fixed rapid deployment) may employ transmitting antennas with
   directional gain up to 26 dBi without any corresponding reduction in the
   transmitter power or spectral density. Corresponding reduction in the peak
   transmit power and peak power spectral density should be the amount in
   decibels that the directional gain of the antenna exceeds 26 dBi.

   (b) Low power devices are also limited to a peak power spectral density of 8
   dBm per one MHz. Low power devices using channel bandwidths other than those
   listed  above are permitted; however, they are limited to a peak power
   spectral density of 8 dBm/MHz. If transmitting antennas of directional gain
   greater than 9 dBi are used, both the peak transmit power and the peak power
   spectral  density should be reduced by the amount in decibels that the
   directional gain of the antenna exceeds 9 dBi.

   (c) The peak transmit power is measured as a conducted emission over any
   interval of continuous transmission calibrated in terms of an RMS-equivalent
   voltage. If the device cannot be connected directly, alternative techniques
   acceptable to the Commission may be used. The measurement results shall be
   properly adjusted for any instrument limitations, such as detector response
   times, limited resolution bandwidth capability when compared to the emission
   bandwidth,  sensitivity, etc., so as to obtain a true peak measurement
   conforming  to  the  definitions in this paragraph for the emission in
   question.

   (d) The peak power spectral density is measured as conducted emission by
   direct connection of a calibrated test instrument to the equipment under
   test. If the device cannot be connected directly, alternative techniques
   acceptable to the Commission may be used. Measurements are made over a
   bandwidth  of  one  MHz or the 26 dB emission bandwidth of the device,
   whichever  is  less.  A resolution bandwidth less than the measurement
   bandwidth can be used, provided that the measured power is integrated to
   show total power over the measurement bandwidth. If the resolution bandwidth
   is approximately equal to the measurement bandwidth, and much less than the
   emission bandwidth of the equipment under test, the measured results shall
   be corrected to account for any difference between the resolution bandwidth
   of the test instrument and its actual noise bandwidth.

   [70 CFR 28467, May 18, 2005]