FCC Logo - Return to the FCC Home Page
Office of Engineering and Technology


Publication Number: 890810 Rule Parts: 24E Publication Date: 03/26/2007
Keyword: Testing Emission Limitations for Part 24 Broadband section 24.200, bandwidth measurement, Personal Communications Service devices

First Category: Radio Service Rules
Second Category: Part 24 Personal Communications Service

Question:   If the emission bandwidth is 4.1 MHZ wide, 1% of this is 41 kHz; can a 30 kHz Resolution and Video BW to test the band edge be used? 

Answer:   Measurements using narrower resolution bandwidths are acceptable and must sum the power from all contiguous reduced resolution bandwidths within the 1% or 1 MHz resolution specified (see below). An alternative is to add an additional correction factor of 10 Log (RBW1/ RBW2) to the 43 +10 Log (P) limit. RBW1 is the narrower measurement resolution bandwidth and RBW2 is either the 1% emissions bandwidth or 1 MHz.  The out of band emission limits Section 24.238 outside of the operating frequency band available for PCS service section 24.229 for Broadband Personal Communication Services Section 24.200 has a power spectrum density limit of 43 +10 Log (P) below the transmitter power (P).

In the adjacent 1 MHz bands above and below the operating frequency, the power spectrum density limit is based on a resolution bandwidth of 1% of the emission bandwidth. The emission bandwidth is measured between two frequencies points above and below the carrier center frequency of the unit-under-testÂ’s emissions where all emission outside of these points is 26 dB below the total transmit power. An accepted practice for measuring the 26 dB points is to use a resolution bandwidth of 1% of the emission bandwidth.

In all other bands outside of the operating frequency ranges, the power spectrum density limit is based on a frequency resolution of 1 MHz.


Please use the Submit Inquiry link at www.fcc.gov/labhelp to send any comments or suggestions for this site

Skip FCC Footer and Contact InfoFederal Communications Commission
445 12th Street, SW
Washington, DC 20554
More FCC Contact Information...
Phone:  888-CALL-FCC (225-5322)
TTY:  888-TELL-FCC (835-5322)
Fax:  202-418-0232
E-mail:  fccinfo@fcc.gov
- Privacy Policy
- Web Policies & Notices
- Customer Service Standards
- Freedom of Information Act