1、 CEA Standard Measurement Procedures for Determining Compliance with FCC Rules for “Cable-Ready Consumer Electronics Equipment” CEA-23-B R-2014 September 2014 NOTICE Consumer Electronics Association (CEA) Standards, Bulletins and other technical publications are designed to serve the public interest
2、 through eliminating misunderstandings between manufacturers and purchasers, facilitating interchangeability and improvement of products, and assisting the purchaser in selecting and obtaining with minimum delay the proper product for his particular need. Existence of such Standards, Bulletins and o
3、ther technical publications shall not in any respect preclude any member or nonmember of CEA from manufacturing or selling products not conforming to such Standards, Bulletins or other technical publications, nor shall the existence of such Standards, Bulletins and other technical publications precl
4、ude their voluntary use by those other than CEA members, whether the standard is to be used either domestically or internationally. Standards, Bulletins and other technical publications are adopted by CEA in accordance with the American National Standards Institute (ANSI) patent policy. By such acti
5、on, CEA does not assume any liability to any patent owner, nor does it assume any obligation whatever to parties adopting the Standard, Bulletin or other technical publication. This document does not purport to address all safety problems associated with its use or all applicable regulatory requirem
6、ents. It is the responsibility of the user of this document to establish appropriate safety and health practices and to determine the applicability of regulatory limitations before its use. This document is copyrighted by the Consumer Electronics Association (CEA) and may not be reproduced, in whole
7、 or part, without written permission. Federal copyright law prohibits unauthorized reproduction of this document by any means. Organizations may obtain permission to reproduce a limited number of copies by entering into a license agreement. Requests to reproduce text, data, charts, figures or other
8、material should be made to CEA. (Formulated under the cognizance of the CEA R4 Video Systems Committee.) Published by CONSUMER ELECTRONICS ASSOCIATION 2014 Technology however, CEA-542-B supersedes both ANSI/EIA-542 and EIA IS-132. CEA-544-B, Low Frequency Immunity of Tuners in a Cable System, Novemb
9、er 2004 Society of Cable Television Engineers ANSI/SCTE SCTE 02 1997 (formerly IPS SP 406), “F“ Port (Female Indoor) Physical Dimensions ANSI/SCTE 40 2004, Digital Network Interface Standard 2.3 Reference Acquisition CEA Standards: Global Engineering Documents, World Headquarters, 15 Inverness Way E
10、ast, Englewood, CO USA 80112-5776; Phone 800-854-7179; Fax 303-397-2740; Internet http:/; Email ANSI/SCTE Standards: Society of Cable Telecommunications Engineers Inc. (SCTE), 140 Philips Road, Exton, PA 19341-1318; Phone 800-542-5040; Fax 610-363-5898; Internet http:/www.scte.org; Email infoscte.o
11、rg Federal Communications Commission (FCC) Regulations: U.S. Code of Federal Regulations (C.F.R.), U.S. Government Printing Office, Washington, D.C. 20401; http:/www.access.gpo.gov/nara/cfr/cfr-table-search.html 3 Mechanical and Electrical Interface 3.1 Impedance As required by 47 C.F.R. 76.605(a)(3
12、), signal interconnection of the cable drop to subscriber receiving devices utilizes shielded coaxial cable at a nominal impedance of 75 ohms. 3.2 Connectors The cable to the subscribers device employs a Type F male connector that mates properly to a Type F female connector conforming to ANSI/SCTE 0
13、2 1997.Cable system signals comply with the technical requirements in 47 C.F.R. Part 76. 3.3 Signals Intended for Reception by Cable-Ready 3.3.1 Levels Under normal operating conditions, a cable television system provides the following signal level range at the first subscriber device at each outlet
14、: a) Maximum Individual Visual Carrier Input Level: + 20 dBmV (10.0 mV across a 75 ohm terminating impedance) as defined in ANSI/SCTE 40 2004 Section 6.1.1 b) Minimum Individual NTSC Visual Carrier Input Level: 0 dBmV (1.00 mV across a 75 ohm terminating impedance) as specified in 47 C.F.R. 76.605(a
15、)(3) 3.3.2 Differential Levels To reduce visible co-channel interference on a dual cable system, the terminated level differential between equivalent channels should be within 5 dB. 3.3.3 Frequency Accuracy of Channels on Cable All NTSC channels, measured at the ground block of the dwelling, are req
16、uired to be within 25 kHz of nominal Standard, HRC or IRC frequency assignments in CEA-542-B, formerly EIA IS-1321. When measured after any on-premise signal processing devices furnished and maintained by the cable operator, the frequency is required to be within 250 kHz of nominal. This requirement
17、 in no way overrules any FCC or other federal regulation requiring tighter tolerance or other nominal frequency than 1FCC regulations reference EIA IS-132; however CEA-542-B supersedes EIA IS-132. CEA-23-B 7 listed in CEA-542-B. 3.3.4 Video C/N The video carrier-to-noise ratio, as defined in 47 C.F.
18、R. Part 76 and measured at the subscriber terminal, is required to be at least 43 dB. 3.4 Amplitude of Other Carriers Delivered to Input of Cable-Ready Receivers 3.4.1 Maximum Individual Carrier Amplitude Under normal operating conditions, the maximum RMS value of any individual signal whose frequen
19、cy is between 5 and 30 MHz does not exceed -7 dBm (+42 dBmV across 75 ohms). The maximum RMS value of any individual signal whose frequency is between 30 and 41 MHz does not exceed -25 dBm (+24 dBmV across 75 ohms). The maximum RMS value of any individual signal whose frequency is between 41 and 48
20、MHz does not exceed -49 dBm (0 dBmV across 75 ohms). The maximum RMS value of any individual signal whose frequency is between 48 and 54 MHz does not exceed -59 dBm (-10 dBmV across 75 ohms). See CEA-544-B. The maximum RMS value of any individual signal whose frequency exceeds 54 MHz (including thos
21、e signals greater than 1,000 MHz) is less than 10.0 mV across a 75 ohm terminating impedance (+20 dBmV). 3.4.2 Maximum Average Power Density Under normal operating conditions, the average level of multiple 6-MHz bandwidth signals whose frequencies exceed 54 MHz is less than +15 dBmV RMS for digital,
22、 and is less than + 15 dBmV peak for analog. 4 Applying to the Cable Ready Television Receiving DeviceCharacteristics Required to Avoid Interference to Others Receiver measurements are required to comply with the specifications of Section 4. 4.1 Cable Input Conducted Emissions See 47 C.F.R. 15.118(c
23、)(5). Spurious signals from 5 MHz up to but not including 54 MHz are limited to -26 dBmV. 4.1.1 Test Procedure The cable input conducted emissions test procedure is significantly different than the procedures for the other four cable ready receiver performance categories. In this test, an absolute m
24、easurement of the emissions emanating from the receiver and appearing at the RF input connector is performed. Emissions emanating from the receiver can be from internal sources, such as the receiver local oscillator, and/or external sources such as direct pick up (DPU) ingress of ambient fields. The
25、 cable input conducted emissions test is performed with the EUT configured in the same manner as described for the DPU performance test, i.e., inside of a shielded enclosure on a rotatable non-metallic table. For the external source test, the EUT is irradiated with a horizontally polarized field at
26、a frequency 2.55 MHz above the desired visual carrier frequency. The ambient field is adjusted for a level of 100 mV/m at the EUT (See Annex A (normative) for details on the calibration of the test enclosure). A total of 12 tests is performed. As is the case with the DPU test procedure, if a coaxial
27、 cable is supplied by the manufacturer, this cable is required to be used for the cable input conducted emissions test; otherwise, it is recommended that a high quality double shielded coaxial cable be used for both the RF input cable and the IF output cable. Placement of the input RF coaxial cable
28、and the AC line cable is important. It is essential that these cables be exposed to the same ambient field as the receiver under test. For this reason no ferrite loading or additional shielding may be used on the RF input cable or AC line cable. However, in order to limit the size of the test volume
29、, it is recommended that these cables exit the receiver chassis and be routed vertically (cross polarized to the impinged ambient field) to the floor of the enclosure. In this manner only a short section of cable is exposed to the horizontally polarized field. Although this procedure does not presen
30、t worst case exposure of the cables, it is a reasonable compromise in limiting the test volume and, therefore, the enclosure size. 4.1.2 Test Conditions CEA-23-B 8 Desired (Test) Channels: Twelve CEA-542-B channels will be tested. Four evenly spaced channels in each of the following bands: a) 54 up
31、to and including 300 MHz, b) 300 up to and including 450 MHz, and c) 450 up to and including 804 MHz. Test Channel Signal Amplitudes (at the EUT RF input port): Desired Visual Carrier: 0 dBmV Desired Aural Carrier: -10 dBmV Modulation: a) Desired Visual Carrier: 10 IRE Flat Field with color burst b)
32、 Desired Aural Carrier: Unmodulated c) Co-Channel Radiated RF Signal: Unmodulated Co-Channel Radiated Field: a) Horizontally Polarized b) Uniform field strength of 100 mV/m Co-Channel Radiated Carrier Frequency: The co-channel radiated carrier frequency is 2.55 MHz above the desired test channel vis
33、ual carrier. As an example, if TV Channel 2 is to be tested, the radiated carrier frequency is 57.8 MHz, 55.25 (visual carrier) plus 2.55 MHz. 4.1.3 Initial Calibration 1) Calibrate the test enclosure in accordance with the procedures contained in Annex A (normative) for each of the twelve test freq
34、uencies. Record the output level of the co-channel interference generator necessary to produce a 100 mV/m ambient field at the EUT for each test channel. 2) Configure the test equipment and EUT as shown in Figure 1. For the first test channel, adjust the desired channel signal generator for a visual
35、 carrier level of 0 dBmV and an aural carrier level of -10 dBmV at the input to the EUT (measured after the customer supplied coax) using a calibrated level signal meter. Set the video modulation to 10 IRE flat field. Tune the EUT to the desired test channel. Record the input signal level and genera
36、tor/attenuator settings required to produce the proper signal levels at the RF input to the EUT. Correct the measurement result for tap loss and amplifier gain. See Figure 1. CEA-23-B 9 Spectrum AnalyzerDesired TV Channel Signal GeneratorCo-Channel Interference CW Signal Generator(Plus Power Amp)Enc
37、losureEUTCenterTransmit AntennaEUT1.0 MRotatable TableRF Input PreamplifierDirectional CouplerOutInTapFigure 1 DPU Conducted Emissions Equipment Configuration 4.1.4 Measurement Procedure Emissions from Internal Sources 1) Verify that the test system is configured and adjusted as described in Section
38、 4.1.3 1) and that the co-channel interference generator is deactivated. 2) Scan the spectrum between 54 MHz and 804 MHz for emissions (excluding the desired test channel). NOTEIt is recommended that the frequency scan be performed in segments in order to achieve the required resolution on the spect
39、rum analyzer display. The spectrum analyzer scan width and resolution bandwidth should be adjusted so that the system noise floor is at least 10 dB below the performance limits specified in 47 C.F.R. 15.118(c)(5). A pre-amplifier with low noise figure is essential for this test. 3) Record the amplit
40、ude and frequency of each emission in units of decibels above one millivolt (dBmV) (75 ohm measurement system impedance). NOTEIn order to improve the accuracy of the measurement, it is recommended that a calibrated signal source be used, in conjunction with the spectrum analyzer, as a signal substit
41、ute. In this manner reliance is placed on the accuracy of the calibrated signal source and not on the spectrum analyzer for this absolute measurement. The calibrated signal source should have an accuracy of 1 dB. Emissions from External Sources 4) Activate the co-channel interference generator. Set
42、the generator frequency to a value 2.55 MHz above the desired channel visual carrier frequency. Adjust the output level of the generator to the setting required to produce a 100 mV/m ambient field as determined in section 4.1.3 1). 5) Center the spectrum analyzer display at the frequency 2.55 MHZ ab
43、ove the desired channel visual carrier frequency. Adjust the scan width and resolution bandwidth of the analyzer so that CEA-23-B 10 the noise floor as displayed on the analyzer is at least 10 dB below the performance limits specified in 47 C.F.R. 15.118(c)(5). 6) Rotate the EUT to achieve the maxim
44、um emission level as displayed on the spectrum analyzer. Record the level of the emission in units of decibels above one millivolt (dBmV) (75 ohm measurement system impedance). If no emissions are observed, record the displayed noise floor level . NOTEIn order to improve the accuracy of the measurem
45、ent, it is recommended that a calibrated signal source be used, in conjunction with the spectrum analyzer, as a signal substitute. In this manner reliance is placed on the accuracy of the calibrated signal source and not on the spectrum analyzer for this absolute measurement. The calibrated signal s
46、ource should have an accuracy of 1 dB. The output of the signal generator should be inserted into the “IN” port of the directional coupler in Figure 1. 7) Compliance with the cable input conducted emissions section of 47 C.F.R. 15.118(c)(5) requires that the emissions measured and recorded in steps
47、(3) and (6) of this section be less than or equal to the limits in Table 1: Frequency Band (MHz) Limits (dBmVAll values are negative) 54 up to and including 300 - 26 300 up to and including 450 - 20 450 up to and including 804 - 15 Table 1 Cable Input Conducted Emission Limits Further, the average o
48、f the emissions magnitudes from 450 to 804 MHz, is no greater than -20 dBmV. See Annex B (normative) for a step by step procedure for calculating the average emission value. 8) Repeat steps in Sections 4.1.3 2) through Section 4.1.4 7) for each of the remaining test channels. 4.2 Re-radiation of Cab
49、le Signals The FCC rule for re-radiation of cable signals appears at 47 C.F.R. 15.118(d), and a test procedure may be found at 47 C.F.R. 76.609(h). 4.3 A/B Switch IsolationBetween Input Ports The A/B switch isolation requirements are found in 47 C.F.R, 15.115(c)(1)(i). A recommended test procedure is FCC MP-9, “FCC Procedure for Measuring Cable Television Switch Isolation“; however, the FCC MP-9 test procedure should be followed over the frequency range identified in Table 2. Table 2 RF Switch Isolation Limits 4.4
