Test Report

FCC ID: GQ4-27T

Test Report

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FCCID_449480

The University of Michigan Radiation Laboratory 3228 EECS Building Ann Arbor, MI 48109-2122 Tel: (734) 764-0500 Measured Radio Frequency Emissions From TRW LF Transmitter (TPM Initiator) Model: 39360-S9V-A0 Report No. 415031-213 May 20, 2004 Copyright © 2004 For: TRW, Inc. 24175 Research Drive Farmington Hills, MI 48335-2642 Contact: Dragan Boroja Tel: 248.442.8610 Fax: 248.478.7241 PO: A435128383 Tests supervised by: Measurements made by: Edward A. Courtney Report approved by: _____________________ Valdis V. Liepa Valdis V. Liepa Research Scientist Summary Tests for compliance with FCC Regulations, Part 15, Subpart C, and for compliance with Industry Canada RSS-210, were performed on TRW, Inc. transmitter, model 39360-S9V-A0. This device is subject to Rules and Regulations as a transmitter. In testing completed 20-May-04, the device tested in the worst case met the allowed specifications for transmitter radiated emissions by 51.9 dB (see p. 7); digital emissions, Class B, were met by at least 20 dB. The conducted emissions tests do not apply, since the device is powered from a 12 VDC system.

1. Introduction TRW model 39360-S9V-A0 was tested for compliance with FCC Regulations, Part 15, adopted under Docket 87-389, April 18, 1989, and with Industry Canada RSS-210, Issue 5, November, 2001. The tests were performed at the University of Michigan Radiation Laboratory Willow Run Test Range following the procedures described in ANSI C63.4-1992 "Methods of Measurement of Radio-Noise Emissions from Low-Voltage Electrical and Electronic Equipment in the Range of 9 kHz to 40 GHz". The Site description and attenuation characteristics of the Open Site facility are on file with FCC Laboratory, Columbia, Maryland (FCC Reg. No: 91050) and with Industry Canada, Ottawa, ON (File Ref. No: IC 2057). 2. Test Procedures and Equipment Used The pertinent test equipment commonly used in our facility for measurements is listed in Table 2.1 below. The middle column identifies the specific equipment used in these tests. Table 2.1 Test Equipment. Test Instrument Eqpt. Used Manufacturer/Model Spectrum Analyzer (0.1-1500 MHz) Hewlett-Packard, 182T/8558B Spectrum Analyzer (9kHz-22GHz) X Hewlett-Packard 8593A SN: 3107A01358 Spectrum Analyzer (9kHz-26GHz) X Hewlett-Packard 8593E, SN: 3412A01131 Spectrum Analyzer (9kHz-26GHz) Hewlett-Packard 8563E, SN: 3310A01174 Spectrum Analyzer (9kHz-40GHz) Hewlett-Packard 8564E, SN: 3745A01031 Power Meter Hewlett-Packard, 432A Power Meter Anritsu, ML4803A/MP Harmonic Mixer (26-40 GHz) Hewlett-Packard 11970A, SN: 3003A08327 Harmonic Mixer (40-60 GHz) Hewlett-Packard 11970U, SN: 2332A00500 Harmonic Mixer (75-110 GHz) Hewlett-Packard 11970W, SN: 2521A00179 Harmonic Mixer (140-220 GHz) Pacific Millimeter Prod., GMA, SN: 26 S-Band Std. Gain Horn S/A, Model SGH-2.6 C-Band Std. Gain Horn University of Michigan, NRL design XN-Band Std. Gain Horn University of Michigan, NRL design X-Band Std. Gain Horn S/A, Model 12-8.2 X-band horn (8.2- 12.4 GHz) Narda 640 X-band horn (8.2- 12.4 GHz) Scientific Atlanta , 12-8.2, SN: 730 K-band horn (18-26.5 GHz) FXR, Inc., K638KF Ka-band horn (26.5-40 GHz) FXR, Inc., U638A U-band horn (40-60 GHz) Custom Microwave, HO19 W-band horn(75-110 GHz) Custom Microwave, HO10 G-band horn (140-220 GHz) Custom Microwave, HO5R Bicone Antenna (30-250 MHz) X University of Michigan, RLBC-1 Bicone Antenna (200-1000 MHz) X University of Michigan, RLBC-2 Dipole Antenna Set (30-1000 MHz) X University of Michigan, RLDP-1,-2,-3 Dipole Antenna Set (30-1000 MHz) EMCO 2131C, SN: 992 Active Rod Antenna (30 Hz-50 MHz) EMCO 3301B, SN: 3223 Active Loop Antenna (30 Hz-50 MHz) X EMCO 6502, SN:2855 Ridge-horn Antenna (300-5000 MHz) X University of Michigan Amplifier (5-1000 MHz) X Avantek, A11-1, A25-1S Amplifier (5-4500 MHz) X Avantek Amplifier (4.5-13 GHz) Avantek, AFT-12665 Amplifier (6-16 GHz) Trek Amplifier (16-26 GHz) Avantek LISN Box University of Michigan Signal Generator Hewlett-Packard 8657B 2

3. Configurations and Identification of Device Under Test The DUT is a 135 kHz LF transmitter designed for an onboard automobile Tire Pressure Monitoring System (TPMS), and as such, it is powered from an automotive 12 VDC source. It consists of two parts. The modulation and 125 kHz RF circuitry is located in the control module, 7 by 3 by 1.5 inches, and the drivers and coil antenna are housed in a plastic case, approximately 3 by 2 by 1.5 inches. The control module also contains a 315 MHz receiver (FCC ID: GQ4-3QR, IC: 1470A-2R) and automobile body module functions. For testing, a generic harness was provided by the manufacturer. The DUT was designed by TRW, Inc., 24175 Research Drive, Farmington Hills, MI 48335-2642. It is identified as: TRW, Inc. Transmitter Model: 39360-S9V-A0 FCC ID: GQ4-27T CANADA: 1470A-8T 3.1 EMI Relevant Modifications No EMI Relevant Modifications were performed by this test laboratory. 4. Emission Limits 4.1 Radiated Emission Limits The DUT tested falls under the category of an Intentional Radiators and the Digital Devices, subject to Subpart C, Section 15.209; and Subpart B, Section 15.109 (transmitter generated signals excluded); and Subpart A, Section 15.33. The applicable testing frequencies with corresponding emission limits are given in Tables 4.1 and 4.2 below. As a digital device, it is exempt. Table 4.1. Radiated Emission Limits (FCC: 15.205, 15.35; IC: RSS-210 (6.2.2(r), 6.3)). (Transmitter) Fundamental Frequency and Spurious* (MHz) (µV/m) 0.009-0.490 2400/F(kHz), 300m 0.490-1.705 24,000/F(kHz), 30m 0.090-0.110 Restricted 0.49-0.51 Bands * Harmonics must be below the fundamental. For extrapolation to other distances, see Section 6.6. 3

Table 4.2. Radiated Emission Limits (FCC: 15.33, 15.35, 15.109; IC: RSS-210, 6.2.2(r)). (Digital Class B) Freq. (MHz) Elim (3m) µV/m Elim dB(µV/m) 30-88 100 40.0 88-216 150 43.5 216-960 200 46.0 960-2000 500 54.0 Note: Average readings apply above 1000 MHz (1 MHz BW) Quasi-Peak readings apply to 1000 MHz (120 kHz BW) 4.2 Conductive Emission Limits Table 4.3 Conducted Emission Limits (FCC:15.107 (CISPR); IC: RSS-210, 6.6). Frequency Class A (dBµV) Class B (dBµV) MHz Quasi-peak Average Quasi-peak Average .150 - 0.50 79 66 66 - 56* 56 - 46* 0.50 - 5 73 60 56 46 5 - 30 73 60 60 50 Notes: 1. The lower limit shall apply at the transition frequency 2. The limit decreases linearly with the logarithm of the frequency in the range 0.15-0.50 MHz: *Class B Quasi-peak: dBµV = 50.25 - 19.12*log( f ) *Class B Average: dBµV = 40.25 - 19.12*log( f ) 3. 9 kHz RBW 5. Radiated Emission Tests and Results 5.1 Anechoic Chamber Measurements To become familiar with the radiated emission behavior of the DUT, the DUT was first studied and measured in a shielded anechoic chamber. In the chamber there is a set-up similar to that of an outdoor 3-meter site, with a turntable, an antenna mast, and a ground plane. Instrumentation includes spectrum analyzers and other equipment as needed. In this case, the receiving antenna was an active loop, placed on a tripod, approximately 1.5 meters above ground. The DUT was laid on the test table as seen in the Attachment-Test Setup Photos. Using the loop antenna we studied emissions up to 2 MHz. The spectrum analyzer resolution and video bandwidths were usually set to 1 kHz, and sometimes to 300 Hz. Emissions were studied with the plane of the loop perpendicular and parallel to the direction of propagation from the DUT. In the chamber we also recorded the spectrum and modulation characteristics of the carrier. These data are presented in subsequent sections 4

5.2 Outdoor Measurements After the chamber measurements, the emissions on our outdoor 3-meter site were measured. For transmitter emissions a loop antenna was used; the resolution bandwidth was usually 9 kHz, but reduced when ambient noise is present. See Appendix for measurement set-up. For digital emissions bicone and dipole antennas were used. See Section 6.6 for field extrapolation of LF transmitter data from 3 m to 300 m. 5.3 Computations and Results To convert the dBm measured on the spectrum analyzer to dB(µV/m), we use expression E3(dBµV/m) = 107 + PR +KA - KG + KE - CF where PR = power recorded on spectrum analyzer, dB, measured at 3 m KA = antenna factor, dB/m KG = pre-amplifier gain, including cable loss, dB KE = pulse operation correction factor, dB (see 6.1) CF = 3/300 m or 3/30 m conversion factor, dB When presenting the data, at each frequency the highest measured emission under all of the possible orientations is given. Computations and results are given in Table 5.1. There we see that as a transmitter, the DUT meets the limit by 51.9 dB. The digital emissions, Class B, were met by 20 dB. 6. Other Measurements and Computations 6.1 Correction For Pulse Operation Under normal operation the transmitter produces a continuous pulse for 660.0 ms. See Figure 6.1. Since the DUT operates in CW mode for more than 100 ms, no duty factor is applied. The duty factor is: KE = 100 ms / 100 ms = 1.0 or 0.0 dB 6.2 Emission Spectrum Using the loop antenna, the emission spectrum was recorded and is shown in Figure 6.2. 6.3 Bandwidth of the Emission Spectrum and Its Level in 110 kHz Restricted Band The measured spectrum of the signal at the lowest operation channel is shown in Figure 6.3. From the plot we see that the -20 dB bandwidth is 24 kHz, and the highest sidelobe in the restricted band is 26.7 dB below the center frequency. 6.4 Effect of Supply Voltage Variation For this test, the relative power radiated was measured at the fundamental as the voltage was varied from 6.0 to 17.0 volts. The emission variation is shown in Figure 6.4. 6.5 Input Voltage and Current V = 14.1 V I = 192 mA (CW emission) 5

6.6 Field Behavior at 135 kHz Because at the specified 300/30 m measurement distance the signal is too small to measure, measurements were made at 3 m. To translate the measurement from 3 m to the 300/30 m distance, we computed the field behavior for a Hertzian (small loop) dipole using equations found in most antenna books, such as, Balanis Antenna Theory Analysis and Design, 1997 John Wiley & Sons, 2nd Edition, pg. 207-208. The applicable results that we need are: Freq (kHz) H-component Extrapolated Position Correction (dB) Notes 135 Vertical – Radial 3m/300m 117.1 dB Axial coupling 135 Vertical –Transverse 3m/300m 121.0 dB Planar coupling 135 Horizontal –Transverse 3m/300m 121.0 dB Planar coupling 270 Vertical – Radial 3m/300m 114.1 dB Axial coupling 270 Vertical –Transverse 3m/300m 111.9 dB Planar coupling 270 Horizontal –Transverse 3m/300m 111.9 dB Planar coupling 405 Vertical – Radial 3m/300m 111.3 dB Axial coupling 405 Vertical –Transverse 3m/300m 104.4 dB Planar coupling 405 Horizontal –Transverse 3m/300m 104.4 dB Planar coupling 540 Vertical – Radial 3m/30m 59.5 dB Axial coupling 540 Vertical –Transverse 3m/30m 60.5 dB Planar coupling 540 Horizontal –Transverse 3m/30m 60.5 dB Planar coupling 675 Vertical – Radial 3m/30m 59.3 dB Axial coupling 675 Vertical –Transverse 3m/30m 60.7 dB Planar coupling 675 Horizontal –Transverse 3m/30m 60.7 dB Planar coupling 810 Vertical – Radial 3m/30m 59.0 dB Axial coupling 810 Vertical –Transverse 3m/30m 60.9 dB Planar coupling 810 Horizontal –Transverse 3m/30m 60.9 dB Planar coupling 945 Vertical – Radial 3m/30m 58.7 dB Axial coupling 945 Vertical –Transverse 3m/30m 61.1 dB Planar coupling 945 Horizontal –Transverse 3m/30m 61.1 dB Planar coupling 1080 Vertical – Radial 3m/30m 58.4 dB Axial coupling 1080 Vertical –Transverse 3m/30m 61.2 dB Planar coupling 1080 Horizontal –Transverse 3m/30m 61.2 dB Planar coupling 1215 Vertical – Radial 3m/30m 58.0 dB Axial coupling 1215 Vertical –Transverse 3m/30m 61.2 dB Planar coupling 1215 Horizontal –Transverse 3m/30m 61.2 dB Planar coupling 1350 Vertical – Radial 3m/30m 57.7 dB Axial coupling 1350 Vertical –Transverse 3m/30m 61.0 dB Planar coupling 1350 Horizontal –Transverse 3m/30m 61.0 dB Planar coupling In the data table, Table 5.1, the measured field is decreased by the dB values given above to represent the field at 300m or 30m, which ever is applicable. The University of Michigan Radiation Laboratory 3228 EECS Building Ann Arbor, MI 48109-2122 Tel: (734) 764-0500 6

Table 5.1 Highest Emissions Measured Transmitter Radiated Emissions TRW LF Initiator; FCC/IC Freq. Ant. Ant. Pr, 3m Det. Ka Kg Conv. E* Elim Pass # kHz Used Orien. dBm Used dB/m dB 3/300 mdBµV/m dBµV/m dB Comments 1 137.3 Loop V/perp -26.2 Pk 9.9 0.0 117.7 -27.0 24.9 loop perp. (axis in dir. of prop.) 51.9 2 137.3 Loop V/par -30.8 Pk 9.9 0.0 121.0 -34.9 24.9 59.8 loop paral. (loop in dir. of prop.) 3 137.3 Loop H, CP -28.0 Pk 9.9 0.0 121.0 -32.1 24.9 57.0 loop horiz. (loop in horiz. plane) 4 274.5 Loop V/perp -66.3 Pk 9.8 0.0 114.1 -63.6 18.8 82.4 loop perp. (axis in dir. of prop.) 5 274.5 Loop V/par -69.9 Pk 9.8 0.0 111.9 -65.0 18.8 83.8 loop paral. (loop in dir. of prop.) 6 274.5 Loop H, CP -68.4 Pk 9.8 0.0 111.9 -63.5 18.8 82.3 loop horiz. (loop in horiz. plane) 7 411.8 Loop V/perp -73.8 Pk 9.8 0.0 111.3 -68.3 15.3 83.6 8 411.8 Loop V/par -75.9 Pk 9.8 0.0 104.4 -63.5 15.3 78.8 9 411.8 Loop H, CP -75.1 Pk 9.8 0.0 104.4 -62.7 15.3 78.0 10 549.0 Loop V/perp -77.4 Pk 9.8 0.0 59.5 -20.1 32.8 52.9 background 11 549.0 Loop V/par -76.3 Pk 9.8 0.0 60.5 -20.0 32.8 52.8 background 12 549.0 Loop H, CP -84.1 Pk 9.8 0.0 60.5 -27.8 32.8 60.6 noise 13 686.3 Loop V/perp -76.2 Pk 9.8 0.0 59.3 -18.7 30.9 49.6 background 14 686.3 Loop V/par -77.5 Pk 9.8 0.0 60.7 -21.4 30.9 52.3 background 15 686.3 Loop H, CP -81.4 Pk 9.8 0.0 60.7 -25.3 30.9 56.2 noise 16 823.5 Loop All -85.6 Pk 9.8 0.0 59.0 -27.8 29.3 57.1 noise 17 960.8 Loop All -74.5 Pk 9.8 0.0 58.7 -16.4 28.0 44.4 background 18 1098.0 Loop All -83.4 Pk 9.8 0.0 58.4 -25.0 26.8 51.8 background 19 1235.3 Loop All -89.4 Pk 9.8 0.0 58.0 -30.6 25.8 56.4 noise 20 1372.5 Loop All -86.5 Pk 9.8 0.0 57.7 -27.4 24.9 52.3 background 21 22 * Averaging applies up to 490 kHz, 0.0 dB in this case 23 Limit at 300m for f<0.490MHz; 30m for f>0.490MHz 24 Measurements made at 3 m, see Sec. 6.6 for extrapolation information 25 Usually, 9 kHz RBW is used, sometimes lower to reduce ambient and instrume 26 Digital Radiated Emissions, Class B Freq. Ant. Ant. Pr Det. Ka Kg E3 E3lim Pass # MHz Used Pol. dBm Used dB/m dB dBµV/m dBµV/m dB Comments 1 2 Digital emission were > 20 dB below the Class B limit 3 4 5 6 7 8 9 10 11 Meas.05/20/2004; U of Mich. 7

Figure 6.1. Transmission modulation characteristics. Figure 6.2. Emission spectrum of the DUT. The amplitudes are only indicative (not calibrated). 8

Figure 6.3.Measured bandwidth of the DUT at 125 kHz. (pulsed) -16.00 -17.00 Relative Amplitude (dB) -18.00 -19.00 -20.00 -21.00 -22.00 -23.00 -24.00 4.0 6.0 8.0 10.0 12.0 14.0 16.0 18.0 Relative Voltage (V) Figure 6.4. Relative emission at 135 kHz vs. supply voltage. 9

Appendix: DUT on OATS Appendix: Close-up of the DUT on OATS 10


Document Created: 2004-06-30 09:21:41
Document Modified: 2004-06-30 09:21:41
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