Test Report Revised

FCC ID: GQ4-22T

Test Report

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                                       The University of Michigan
                                         Radiation Laboratory
                                          3228 EECS Building
                                       Ann Arbor, MI 48109-2122
                                          Tel: (734) 764-0500


                                  Measured Radio Frequency Emissions
                                                From

                                       TRW Transmitter
                                      Model: 39350-S3V-A0

                                         Report No. 415031-176
                                           October 22, 2003


                                            Copyright © 2003


                                                 For:
                                              TRW, Inc.
                                         24175 Research Drive
                                    Farmington Hills, MI 48335-2642

                                                 Contact:
                                             David Kapolka
                                       Tel: 248.478.7210 ext 4858
                                            Fax: 248.478.7241


                                               Tests supervised by:
Measurements made by:       Edward M. 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 39350-S3V-A0. This device is
subject to Rules and Regulations as a transmitter.
         In testing completed 28-Jul-03, the device tested in the worst case met the allowed specifications
for transmitter radiated emissions by 51.6 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 39350-S3V-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 is housed in a plastic
case approximately 3 by 2 by 1.5 inches. Coil is internal. For testing, a generic harness was provided by
the manufacturer. The DUT is designed to operating over a range of frequencies between 125 and 160
kHz.
          The DUT was designed by TRW, Inc., 24175 Research Drive, Farmington Hills, MI 48335-2642.
It is identified as:

                           TRW, Inc. Transmitter
                           Model: 39350-S3V-A0
                           FCC ID: GQ4-22T
                           CANADA: 1470A-3T

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 1 kHz. See
Appendix for measurement set-up. For digital emissions bicone and dipole antennas were used. See
Section 6.6 for field extrapolation of 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 51.6 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 662.5 ms. Since the DUT
operates in CW mode for more than 100 ms, no duty factor is applied. See Figure 6.1.

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
The measured spectrum of the signal is shown in Figure 6.3. From the plot we see that the -20 dB
bandwidth is 24 kHz, and the -26 dB bandwidth is 26 kHz.

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
9.0 to 18.0 volts. The emission variation is shown in Figure 6.4.

6.5 Input Voltage and Current
                        V = 13.5 V
                        I = 0.11 A (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    137.0   Loop V/perp -25.9 Pk     9.9 0.0 117.7 -26.7 24.9            51.6   loop perp. (axis in dir. of prop.)
 2    137.0   Loop V/par -30.6 Pk      9.9 0.0 121.0 -34.7 24.9            59.6   loop paral. (loop in dir. of prop.)
 3    137.0   Loop H, CP -28.5 Pk      9.9 0.0 121.0 -32.6 24.9            57.5   loop horiz. (loop in horiz. plane)
 4    274.0   Loop V/perp -66.6 Pk     9.8 0.0 114.1 -63.9 18.8            82.7   loop perp. (axis in dir. of prop.)
 5    274.0   Loop V/par -70.4 Pk      9.8 0.0 111.9 -65.5 18.8            84.3   loop paral. (loop in dir. of prop.)
 6    274.0   Loop H, CP -70.2 Pk      9.8 0.0 111.9 -65.3 18.8            84.1   loop horiz. (loop in horiz. plane)
 7    411.0   Loop V/perp -56.3 Pk     9.8 0.0 111.3 -50.8 15.3            66.1   background
 8    411.0   Loop V/par -61.2 Pk      9.8 0.0 104.4 -48.8 15.3            64.1   noise
 9    411.0   Loop H, CP -60.9 Pk      9.8 0.0 104.4 -48.5 15.3            63.8   noise
10    548.0   Loop V/perp -69.7 Pk     9.8 0.0 59.5 -12.4  32.8            45.2   noise
11    548.0   Loop V/par -72.3 Pk      9.8 0.0 60.5 -16.0  32.8            48.8   noise
12    548.0   Loop H, CP -77.2 Pk      9.8 0.0 60.5 -20.9  32.8            53.7   noise
13    685.0   Loop V/perp -62.7 Pk     9.8 0.0 59.3 - 5.2  30.9            36.1   background
14    685.0   Loop V/par -68.2 Pk      9.8 0.0 60.7 -12.1  30.9            43.0   noise
15    685.0   Loop H, CP -67.2 Pk      9.8 0.0 60.7 -11.1  30.9            42.0   noise
16    822.0   Loop All -67.5 Pk        9.8 0.0 59.0 - 9.7  29.3            39.0   noise
17    959.0   Loop All -66.3 Pk        9.8 0.0 58.7 - 8.2  28.0            36.2   background
18   1096.0   Loop All -74.3 Pk        9.8 0.0 58.4 -15.9  26.8            42.7   noise
19   1233.0   Loop All -65.5 Pk        9.8 0.0 58.0 - 6.7  25.8            32.5   background
20   1370.0   Loop All -73.9 Pk        9.8 0.0 57.7 -14.8  24.9            39.7   noise
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.07/28/2003; U of Mich.

                                                      6


                    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)


                          5.00
                          3.00
                           1.00
Relative Amplitude (dB




                          -1.00
                          -3.00
                          -5.00
                          -7.00
                          -9.00
                         -11.00
                         -13.00
                         -15.00
                                  7.0   8.0   9.0   10.0 11.0 12.0 13.0 14.0 15.0 16.0 17.0 18.0
                                                          Relative Voltage (V)



                             Figure 6.4. Relative emission at 135 kHz vs. supply voltage.




                                                             9



Document Created: 2003-10-24 11:12:49
Document Modified: 2003-10-24 11:12:49

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