CISPR 12 OTS to ALSE/VTC Correlation for 12 OTS to ALSE/VTC Correlation for the ... Page 2 of 22 Table of Contents 1 ... meets the measurement accuracy of CISPR 16.

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<ul><li><p>CISPR 12 OTS to ALSE/VTC Correlation for the Elite Electronic Engineering Whole Vehicle </p><p>RF Shielded Test Facility </p><p>CLP-CCOTS-002 </p><p> For Elite Electronic Engineering 1516 Centre Circle Downers Grove, Il 60174 Document Number CLP-CCOTS-002 Test Specification CISPR 12 Edition 6.0 January 2009 Amendment 1 </p><p> Written By Tim Royer and Stanley D. Dolecki iNARTE Certified: ALT-0151-E </p><p> Approved By Craig Fanning EMC Lab Manager iNARTE Certified: EMC-000296-NT iNARTE Certified: ALT-0188-E </p><p>Elite Electronic Engineering Inc. 1516 Centre Circle Downers Grove, IL 60515 Tel : (630) 495-9770 Fax: (630) 495-9785 www.elitetest.com </p></li><li><p> CLP-CCOTS-002 </p><p>This document shall not be reproduced, except in full, without the written approval of Elite Electronic Engineering Inc. </p><p> Page 2 of 22 </p><p>Table of Contents </p><p>1. Report Revision History ...........................................................................................................................3 2. Introduction ..............................................................................................................................................3 2.1. Purpose....................................................................................................................................................3 2.2. Requirement:............................................................................................................................................3 2.3. Applicable Documents .............................................................................................................................3 2.4. Equipment Needed: .................................................................................................................................3 2.5. Process Overview: ...................................................................................................................................3 3. ALSE VTC Description.............................................................................................................................3 4. CISPR 12 OTS and ALSE VTC Correlation Procedure...........................................................................3 5. Sample Data ............................................................................................................................................3 6. Measurement Uncertainty:.......................................................................................................................3 7. Historical/ Proficiency Data to Show Repeatability ..................................................................................3 8. Confirmation of Measurements Made on Vehicles in the VTC................................................................3 9. Certification ..............................................................................................................................................3 </p></li><li><p> CLP-CCOTS-002 </p><p>Page 3 of 22 </p><p>1 . RE P O R T RE V I S I O N H I S T O R Y REVISIONS DATE DESCRIPTION </p><p>001 02/02/2010 INITIAL RELEASE </p><p>002 03/19/2010 ADDED HISTORICAL/PROFICIENCY DATA TO SHOW REPEATABILITY IN SECTION 7 AND ADJUSTED THE OTHER SECTION NUMBERING AS NEEDED. </p></li><li><p> CLP-CCOTS-002 </p><p>Page 4 of 22 </p><p>2 . I N T R O D U C T I O N </p><p>2.1. Purpose In November of 2009, a series of measurements were made in order to determine the factor which correlates 3 meter radiated emissions measurements made in Elites Vehicle Test Chamber (VTC) to 3 meter radiated emissions measurements made on a CISPR 12 Open Test Site (OTS). This document provides a description of the process, and the resulting data obtained, to meet the correlation requirement of CISPR 12 Edition 6.0 January 2009- Amendment 1, Clause 5.2.2 Absorber Lined Shielded Enclosure (ALSE) Requirements; Sub-clause 5.2.2.1 Correlation. </p><p>2.2. Requirement: Per CISPR 12 Edition 6.0, Clause 5.2.2 Absorber Lined Shielded Enclosure (ALSE) requirements; Sub-clause 5.2.2.1 Correlation, an ALSE may be used for vehicle level radiated emissions testing provided that the results obtained can be correlated with the results obtained from measurements made using a OTS. The specification does not define a specific process, metrics, or other parameters. </p><p>2.3. Applicable Documents </p><p>CISPR 12 Edition 6.0 January 2009 Amendment 1 </p><p>Vehicles, boats and combustion engines Radio disturbances characteristics Limits of methods of measurement for the protection of off-board receivers. </p><p>2.4. Equipment Needed: 1 ComPower CG515 Comb Generator 2 Rhode &amp; Schwarz EMI Receiver, Model ESCI (or equivalent) 3 Chase Model CBL6112 Bilog antenna 4 2801 Type coax cable 5 Workstation or laptop with Field measurement and Universal Emissions applications Note: The same equipment and noise generator must be used for the outdoor and indoor measurements. </p><p>2.5. Process Overview: This procedure was used to gather data in order to establish correlation between the OTS and VTC. It is intended for initial characterization of the chamber and establishing new test points in the chamber. </p><p> All radiated measurements, OTS and ALSE, shall be made at a 3m separation distance. A set of outdoor reference measurements are made in the required frequency range using a receive </p><p>antenna, EMI receiver, and a stable noise source (Com Power CG-515 Comb Generator). Outdoor measurements are made over the frequency range of 30 MHz to 1 GHz in 5 MHz intervals. Measurements are made with the receive antenna in both the horizontal and vertical orientations. The </p><p>artifact is oriented in the same polarity as the receive antenna. This OTS data is recorded and saved as the Reference Measurements. </p><p> The VTC is laid out such that vehicles can be placed in one fixed location to utilize fixed receive antenna points for the vehicle test. </p><p> The measurements are repeated inside the chamber at each reference point. The measurements are made using the same equipment and measurement parameters that were used for the OTS measurements. </p><p> The Correlation Factor (CF) is the delta (in dB) between the OTS Reference Data and the measurements made on the artifact in the VTC. The CF is then applied to the measurements made on a vehicle when tested inside the VTC. </p><p> The chamber characterization and CF shall be made once unless the test site, test facility, or equipment are changed or modified. </p></li><li><p> CLP-CCOTS-002 </p><p>Page 5 of 22 </p><p>3 . ALSE VTC DE S C R I P T I O N Elite Electronic Engineering Incorporated's whole vehicle shielded test enclosure measures 105ft. by 33ft. by 20ft. high. The enclosure is designed for vehicle testing and is equipped with an exhaust elimination system to remove vehicle emissions from the area. The enclosure is setup in a semi-anechoic configuration utilizing panels of anechoic material. The location of the anechoic panels is clearly marked on the floor of the chamber to ensure repeatable and consistent test setups. The chamber floor has been marked off for vehicle positioning, antenna locations, and reference points. There are currently two antenna reference points established in the chamber for radiated emissions measurements. See Figure 1. </p><p> Figure 1 CISPR ALSE Test Setup Diagram </p></li><li><p> CLP-CCOTS-002 </p><p>Page 6 of 22 </p><p>4 . C ISPR 12 OTS A N D ALSE VTC C O R R E L A T I O N PR O C E D U R E A Com Power CG515 comb generator was used as the reference standard for all measurements. The reference standard was configured with a 5 MHz output for all measurements. It was setup in the OTS, using the same setup as would be used for a vehicle radiated emissions test. The reference standard was placed at the same location and height as used for the vehicle reference point. All measurements were made at a 3 meter separation distance. The receive antenna and artifact heights were both 1.8 meters above the cement driveway. All signals emanating from the reference standard were measured (narrowband signals at a 5 MHz interval) in the frequency range of 30 MHz to 1GHz. Measurements were made using both veridical and horizontal antenna polarization. These measurements were used as the Reference Measurements. The measurements were repeated inside the VTC (ALSE) chamber for both vertical and horizontal antenna polarizations, and at both receive antenna reference points. All measurements were performed using the peak detector function of an EMI receiver with 120 kHz BW that meets the measurement accuracy of CISPR 16. The measured data was used to derive correlation factors for each frequency, antenna polarization and antenna reference point. The factor was derived as noted below: </p><p>Correlation Factor (dB) @ fx = Ref Measurement (dBuV) @ fx Indoor Measured Value (dBuV) @ fx; </p><p>where the Ref Measurement = the measurement made on the OTS. During a CISPR 12 radiated emissions test within the VTC, the emissions radiating from the vehicle are calculated as shown below: FI (dBuV/m) = Meter Reading (dBuV) + Antenna Factor (dB) + Cable Loss (dB) + Correlation Factor (dB) This FI is then compared to the radiated emissions limits specified in CISPR 12 to determine compliance. </p><p>5 . SA M P L E DA T A The correlation factor data presented in this document is the actual reference data and chamber measurements used to derive the correction factors for testing. Comparison of the emissions measured from the artifact on the OTS and in the VTC are shown Figure 2 and Figure 3. The correlation data factors in tabular form are presented on pages 12 through 22. </p></li><li><p> CLP-CCOTS-002 </p><p>Page 7 of 22 </p><p>Outdoor vs. Indoor Measurements: Vertical Posistions 1 &amp; 2 - w/ Ferrite</p><p>20</p><p>30</p><p>40</p><p>50</p><p>60</p><p>70</p><p>80</p><p>30 130 230 330 430 530 630 730 830 930</p><p>Frequency (MHz)</p><p>dBuV</p><p>/m</p><p>Outdoor Measuremets</p><p>Inoor: Position 1</p><p>Indoor: Position 2</p><p> Figure 2 Artifact Emissions OTS and VTC Vertical Polarization </p><p>Outdoor vs. Indoor Measurements: Horizontal - Posisitions 1 &amp; 2 - w/ Ferrite</p><p>20</p><p>30</p><p>40</p><p>50</p><p>60</p><p>70</p><p>80</p><p>30 130 230 330 430 530 630 730 830 930</p><p>Frequency (MHz)</p><p>dBuV</p><p>/m</p><p>Outdoor Measurements</p><p>Indoor:Position 1</p><p>Indoor: Position 2</p><p> Figure 3 Artifact Emissions OTS and VTC Horizontal Polarization </p></li><li><p> CLP-CCOTS-002 </p><p>Page 8 of 22 </p><p>6 . M E A S U R E M E N T UN C E R T A I N T Y : Measurement Uncertainty is used by ISO 17025 Test Laboratories to calculate how accurate their measurements should be and in order to develop a confidence factor. Uncertainty guidelines are specified in CISPR 16-4-2: 2003. Uncertainty budgets take into consideration all of the pieces of the measurement system. The weight or probability distribution is applied to each piece of the measurement system per industry standards. The uncertainty budget then provides a measurement uncertainty with a confidence factor (usually 95%). Uncertainty is not applied to measurements in order to determine pass/fail. The 95% uncertainty budget for CISPR 12 radiated emissions measurements made at 3 meters are shown in Table 1. </p><p> Table 1 Measurement Uncertainty Budget Worksheet for Radiated Emissions at 3 meters </p><p>7 . H I S T O R I C A L / PR O F I C I E N C Y DA T A T O SH O W RE P E A T A B I L I T Y In March 2010, a series of measurements were made on the same artifact that was used for the VTC and OTS correlation measurements in order to show the repeatability of the measurements made in the VTC. The artifact and test equipment was setup and torn down between each run to show setup and test repeatability. The artifacts emissions were measured in the VTC and the correlation factors added to the measured values. The corrected emissions were then plotted along with the November 2009 measurements from the artifact on the OTS. The +/-5.2 dB uncertainty budget limits were also applied to the plots for reference. The uncertainty budget is based upon a 95% confidence factor. Therefore, at least 95% of the measurements made in the VTC shall be within +/- 5.2 dB of the OTS measurements. The data is shown on Figures 4 and 5. As can be seen from the data, at least 95% of the measured values (with correlation factor applied) were within the +/-5.2 dB uncertainty budget. </p><p>Quality Assurance Form QAF-27-01Elite Electronic Engineering, Inc.</p><p> Measurement Uncertainty Budget Worksheet</p><p>17025 Ref: QAP-27Revision 1.1</p><p>Description: Radiated Emissions in a 3 meter anechoic chamber</p><p>Chase Bilog AntennaR&amp;S EMC Receiver (Models ESIB and ESCI)</p><p>Probability Distribution Uncertainty (dB)Contributions Description 30 - 1000MHzReceiver Reading 1.73 2.00Attenuation: antenna-receiver Normal 2.00 0.50Antenna Factor Normal 2.00 2.00Cable Factor Normal 2.00 0.50Receiver Corrections - sine wave voltage Normal 2.00 1.00Receiver Corrections - pulse amplitude response Rectangular 1.73 0.87Receiver Corrections - pulse repetitiion rate response Rectangular 1.73 0.87Receiver Corrections - noise floor proximity Normal 1.40 0.50Mismatch: antenna-receiver U-shaped 1.41 1.00Antenna Corrections - AF frequency interpolation Rectangular 1.73 1.00Antenna Corrections - AF height deviations Rectangular 1.73 1.00Antenna Corrections - directivity difference Rectangular 1.73 1.00Antenna Corrections - phase center location 1.00 0.75Antenna Corrections - cross polorization 1.00 0.75Antenna Corrections - balance Rectangular 1.73 1.00Site Corrections - site imperfections Triangular 2.45 1.63Site Corrections - separation distance Rectangular 1.73 0.17Site Corrections - table height Normal 2.00 0.05Combined Uncertainty (+/-) 2.60Expanded Uncertainty (+/-) 5.20</p><p>k-value</p></li><li><p> CLP-CCOTS-002 </p><p>Page 9 of 22 </p><p>CISPR12 Indoor Repeatability: Actual Measurements vs Reference Curve - Vertical Antenna</p><p>20</p><p>25</p><p>30</p><p>35</p><p>40</p><p>45</p><p>50</p><p>55</p><p>60</p><p>65</p><p>70</p><p>30 130 230 330 430 530 630 730 830 930</p><p>Frequency (MHz)</p><p>Fiel</p><p>d M</p><p>easu</p><p>rem</p><p>ent (</p><p>dBuV</p><p>/m)</p><p>Reference Curve</p><p>+5.2dB Upper Tolerance</p><p>-5.2dB Lower Tolerance</p><p>Vertical, Run1</p><p>Vertical, Run 2</p><p>Vertical, Run 3</p><p> Vertical:</p><p>Run 1:&gt;5.2dB 2 delta's 97.4 % of measured emissions within +/- 5.2 dB of the reference.</p></li><li><p> CLP-CCOTS-002 </p><p>Page 10 of 22 </p><p>CISPR12 Indoor Repeatability: Actual Measurements vs Reference Curve - Horizontal Antenna</p><p>20</p><p>25</p><p>30</p><p>35</p><p>40</p><p>45</p><p>50</p><p>55</p><p>60</p><p>65</p><p>70</p><p>75</p><p>30 130 230 330 430 530 630 730 830 930</p><p>Frequency (MHz)</p><p>Fiel</p><p>d M</p><p>easu</p><p>rem</p><p>ent (</p><p>dBuV</p><p>/m)</p><p>Reference Curve</p><p>+5.2dB Upper Tolerance</p><p>-5.2dB Lower Tolerance</p><p>Horizontal Run 1</p><p>Horizontal, Run 2</p><p> Horizontal, Run 3</p><p> Horizontal:</p><p>Run 1:&gt;5.2dB 2 delta's 96.9 % of measured emissions within +/- 5.2 dB of the reference.</p></li><li><p> CLP-CCOTS-002 </p><p>Page 11 of 22 </p><p>It should be noted that during the March 2010 historical/proficiency artifact testing to show repeatability, the chamber absorber panels were not completely setup and torn down between sweeps. This was done for two reasons: </p><p>1) Absorber panel movement was not seen as an issue since the panels are labeled and placed in the sa...</p></li></ul>

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