test report

FCC ID: GQ4-42T

Test Report

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FCCID_1096469

                            University of Michigan Radiation Laboratory
                      FCC Part 15, IC RSS-210/Gen - Test Report No. 417124-497



                                      The University of Michigan
                                        Radiation Laboratory
                                         3228 EECS Building
                                      Ann Arbor, MI 48109-2122
                                         Tel: (734) 764-0500
                                         Fax: (734) 647-2106


                                 Measured Radio Frequency Emissions
                                               From

                                TRW Inc. TPMS Transmitter
                                   FCC ID: GQ4-42T
                                     IC: 1470A-23T

                                      Test Report No. 417124-497
                                            April 13, 2009

                                              Copyright © 2009


                                                For:
                                              TRW Inc.
                                        24175 Research Drive
                                   Farmington Hills, MI 48335-2642
                                      Contact: Muaiad Al-Habib
                                      Muaiad.Al-Habib@trw.com
                                        Phone: 248.699.4801
                                         Fax: 248.478.7241


                                                  Testing supervised by:
Measurements made by: Valdis V. Liepa              Report Approved by:__________________________
                                                                              Valdis V. Liepa
Test report written by:   Joseph D. Brunett                                   Research Scientist

Summary

Tests for compliance with FCC Regulations, CFR 47, Part 15 and with Industry Canada RSS-210/Gen,
were performed on a TRW, FCC ID: GQ4-42T, IC: 1470A-23T. This device under test (DUT) is subject
to the rules and regulations as a Transmitter.
         In testing completed on March 18, 2009, the DUT tested met the allowed specifications for
radiated emissions by 1.9 dB. Conducted emissions are not subject to regulation as the DUT is powered
by a 3 VDC battery.




                                                 Page 1 of 1


                                 University of Michigan Radiation Laboratory
                           FCC Part 15, IC RSS-210/Gen - Test Report No. 417124-497



                                                       Table of Contents

1.   Introduction ...................................................................................................................................... 3
2.   Equipment Used ............................................................................................................................... 3
3.   Device Under Test ........................................................................................................................... 4
     3.1       Description & Block Diagram .............................................................................................. 4
     3.2       Variants & Samples .............................................................................................................. 4
     3.3       Modes of Operation .............................................................................................................. 4
     3.4       Exemptions ........................................................................................................................... 4
     3.5       EMC Relevant Modifications ............................................................................................... 4
4.   Emissions Limits.............................................................................................................................. 5
     4.1       Radiated Emissions Limits.................................................................................................... 5
     4.2       Power Line Conducted Emissions Limits ............................................................................. 5
5.   Measurement Procedures ................................................................................................................. 6
     5.1       Semi-Anechoic Chamber Radiated Emissions...................................................................... 6
     5.2       Outdoor Radiated Emissions ................................................................................................. 6
     5.3       Radiated Field Computations ................................................................................................ 6
     5.4       Indoor Power Line Conducted Emissions ............................................................................. 6
     5.5       Supply Voltage Variation...................................................................................................... 7
6.   Test Results ...................................................................................................................................... 7
     6.1       Radiated Emissions ............................................................................................................... 7
     6.1.1         Correction for Pulse Operation ......................................................................................... 7
     6.1.2         Emission Spectrum ........................................................................................................... 7
     6.1.3         Emission Bandwidth ......................................................................................................... 7
     6.1.4         Supply Voltage and Supply Voltage Variation ................................................................. 7
     6.2       Conducted Emissions ............................................................................................................ 7




                                                                 Page 2 of 2


                            University of Michigan Radiation Laboratory
                      FCC Part 15, IC RSS-210/Gen - Test Report No. 417124-497

1. Introduction

This TRW Transmitter was tested for compliance with FCC Regulations, Part 15, adopted under Docket
87-389, April 18, 1989 as subsequently amended, and with Industry Canada RSS-210/Gen, Issue 7, June
2007. Tests were performed at the University of Michigan Radiation Laboratory Willow Run Test Range
following the procedures described in ANSI C63.4-2003 "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 2057A-1).

2. Equipment Used

The test equipment commonly used in our facility is listed in Table 2.1. Except where indicated as a pre-
test, monitoring, or support device; all equipment listed below is a part of the University of Michigan
Radiation Laboratory (UMRL) quality system. This quality system has been established to ensure all
equipment has a clearly identifiable classification, calibration expiry date, and that all calibrations are
traceable to national standards.
                                        Table 2.1 Test Equipment.
            Test Instrument             Used                Manufacturer/Model                Q Number
 Spectrum Analyzer (9kHz-26GHz)                 Hewlett-Packard 8593E, SN: 3412A01131          HP8593E1
 Spectrum Analyzer (9kHz-6.5GHz)                Hewlett-Packard 8595E, SN: 3543A01546          JDB8595E
 Power Meter                                    Hewlett-Packard, 432A                          HP432A1
 Harmonic Mixer (26-40 GHz)                     Hewlett-Packard 11970A, SN: 3003A08327        HP11970A1
 Harmonic Mixer (40-60 GHz)                     Hewlett-Packard 11970U, SN: 2332A00500        HP11970U1
 Harmonic Mixer (75-110 GHz)                    Hewlett-Packard 11970W, SN: 2521A00179        HP11970W1
 Harmonic Mixer (140-220 GHz)                   Pacific Millimeter Prod., GMA, SN: 26         PMPGMA1
 S-Band Std. Gain Horn                          S/A, Model SGH-2.6                              SBAND1
 C-Band Std. Gain Horn                          University of Michigan, NRL design              CBAND1
 XN-Band Std. Gain Horn                         University of Michigan, NRL design            XNBAND1
 X-Band Std. Gain Horn                          S/A, Model 12-8.2                              XBAND1
 X-band horn (8.2- 12.4 GHz)                    Narda 640                                      XBAND2
 X-band horn (8.2- 12.4 GHz)                    Scientific Atlanta , 12-8.2, SN: 730           XBAND3
 K-band horn (18-26.5 GHz)                      FXR, Inc., K638KF                              KBAND1
 Ka-band horn (26.5-40 GHz)                     FXR, Inc., U638A                              KABAND1
 U-band horn (40-60 GHz)                        Custom Microwave, HO19                         UBAND1
 W-band horn(75-110 GHz)                        Custom Microwave, HO10                         WBAND1
 G-band horn (140-220 GHz)                      Custom Microwave, HO5R                         GBAND1
 Bicone Antenna (30-250 MHz)                    University of Michigan, RLBC-1                  LBBIC1
 Bicone Antenna (200-1000 MHz)                  University of Michigan, RLBC-2                  HBBIC1
 Dipole Antenna Set (30-1000 MHz)               University of Michigan, RLDP-1,-2,-3            UMDIP1
 Dipole Antenna Set (30-1000 MHz)               EMCO 3121C, SN: 992 (Ref. Antennas)             EMDIP1
 Active Rod Antenna (30 Hz-50 MHz)              EMCO 3301B, SN: 3223                           EMROD1
 Active Loop Antenna (30 Hz-50 MHz)             EMCO 6502, SN:2855                            EMLOOP1
 Ridge-horn Antenna (300-5000 MHz)              University of Michigan                          UMRH1
 Amplifier (5-1000 MHz)                         Avantek, A11-1, A25-1S                         AVAMP1
 Amplifier (5-4500 MHz)                         Avantek                                        AVAMP2
 Amplifier (4.5-13 GHz)                         Avantek, AFT-12665                             AVAMP3
 Amplifier (6-16 GHz)                           Trek                                            TRAMP1
 Amplifier (16-26 GHz)                          Avantek                                        AVAMP4
 LISN Box                                       University of Michigan                         UMLISN1
 Signal Generator                               Hewlett-Packard 8657B                            HPSG1

                                                Page 3 of 3


                             University of Michigan Radiation Laboratory
                       FCC Part 15, IC RSS-210/Gen - Test Report No. 417124-497

3. Device Under Test

3.1 Description & Block Diagram
The DUT is a 315 MHz Tire Pressure Monitoring Sensor (TPMS) designed for automotive/vehicular
applications. It is powered by a 3 VDC lithium battery and is housed in a plastic case approximately 6 x 7
x 2 cm in dimension. The DUT is laser welded and permanently affixed in the wheel of a tire. The DUT
is designed and manufactured by TRW Automotive Electronics, 2240 Cranbrook Drive, Auburn, New
York, 13021.

    Sample               [Make], Model                [S/N],P/N               EMC Consideration
    DUT                  [TRW], 220644112             [8000328A]              FCC/IC test sample
    Open sample          [TRW], 220644112             -                       Photos / voltage variation


3.2 Variants & Samples
There is only a single variant of this device. One fully functional sample was provided for testing along
with one un-sealed version for photographs and voltage variation. Via a manufacturer custom LF
command, the device was placed in CW transmit mode for harmonics and fundamental peak emissions
measurement.

3.3 Modes of Operation
The DUT periodically transmits tire pressure data. The device is also capable of being automatically
actuated (via LF interrogation) either by in-vehicle LF initiators or by trained personnel during servicing.
Per FCC correspondence, service modes fall under FCC part 15.231(a)(5). Figure 6.1 demonstrates
compliance with both 15.231(a)(2) and (5). A detailed list of all operating modes is included in the
Description of Operation exhibit.

3.4 Exemptions

     The DUT is permanently installed in a transportation vehicle. As such, digital emissions are exempt
     from regulation (per FCC 15.103(a) and IC correspondence on ICES-003).

     The DUT employs some modes of operation that alert the vehicle user of sudden changes in tire
     pressure. Such alert modes fall under FCC 15.231(a)(4), and may operate during the pendency of the
     alarm condition.

3.5 EMC Relevant Modifications
No EMI Relevant Modifications were performed by this test laboratory.




                                                 Page 4 of 4


                             University of Michigan Radiation Laboratory
                       FCC Part 15, IC RSS-210/Gen - Test Report No. 417124-497

4. Emissions Limits

4.1 Radiated Emissions Limits
The DUT tested falls under the category of an Intentional Radiator. The applicable testing frequencies and
corresponding emission limits set by both the FCC and IC are given in Tables 4.1 and 4.2 below.
Table 4.1. TX Emission Limits (FCC: 15.231(e), .205(a); IC: RSS-210 2.7 T5).
                                           Fundamental                        Spurious**
                Frequency                 Ave. Elim (3m)                    Ave. Elim (3m)
                  (MHz)                (µV/m)       dB (µV/m)            (µV/m)       dB (µV/m)
               260.0-470.0           1500-5000*                          150-500
                   315.0                2417           67.7               241.7          47.7
                   433.9                4399           72.9               439.9          52.9
                322-335.4
                                              Restricted
                399.9-410                                                   200             46.0
                                               Bands
                 608-614
            960-1240/1427(IC)
                1300-1427
               1435-1626.5
                                              Restricted
            1645.5-1646.5 (IC)                                              500             54.0
                                               Bands
                1660-1710
              1718.9-1722.2
                2200-2300
         * Linear interpolation, formula: E = -2833.2 + 16.67*f (MHz)
        ** Measure up to tenth harmonic; 120 kHz BW up to 1 GHz, 1 MHz BW above 1 GHz
Table 4.2. Spurious Emission Limits (FCC: 15.33, .35, .109/209; IC: RSS-210 2.7, T2)

                      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 RBW), PRF of intentional emissions > 20 Hz for QPK to apply.


4.2 Power Line Conducted Emissions Limits
Table 4.3 Emission Limits (FCC:15.107 (CISPR); IC: RSS-Gen, 7.2.2 T2).
      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

                                                  Page 5 of 5


                             University of Michigan Radiation Laboratory
                       FCC Part 15, IC RSS-210/Gen - Test Report No. 417124-497

5. Measurement Procedures

5.1 Semi-Anechoic Chamber Radiated Emissions
To become familiar with the radiated emission behavior of the DUT, the device is first studied and
measured in our shielded semi-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.
         The DUT is laid on the test table as shown in the included block diagram. A shielded loop
antenna is employed when studying emissions from 9 kHz to 30 MHz. Above 30 MHz and below 250
MHz a biconical antenna is employed. Above 250 MHz a ridge or and standard gain horn antennas are
used. The spectrum analyzer resolution and video bandwidths are set so as to measure the DUT emission
without decreasing the emission bandwidth (EBW) of the device. Emissions are studied for all
orientations (3-axes) of the DUT and all test antenna polarizations. In the chamber spectrum and
modulation characteristics of the carrier are recorded. This data is presented in subsequent sections.

5.2 Outdoor Radiated Emissions
After measurements are performed indoors, emissions on our outdoor 3-meter Open Area Test Site
(OATS) are made. If the DUT connects to auxiliary equipment and is table or floor standing, the
configurations prescribed in ANSI C63.4 are employed. Alternatively, an on-table layout more
representative of actual use may be employed if the resulting emissions appear to be worst-case in such a
configuration. Any intentionally radiating elements are placed on the test table flat, on their side, and on
their end (3-axes) and worst case emissions are recorded. For each configuration the DUT is rotated 360
degrees about its azimuth and the receive antenna is raised and lowered between 1 and 4 meters to
maximize radiated emissions from the device. For devices with intentional emissions below 30 MHz, our
shielded loop antenna at a 1 meter received height is used and low frequency field extrapolation to the
regulatory limit distance is employed as needed. Emissions between 30 MHz and 1 GHz are measured
using tuned dipoles and/or biconical antennas. Care is taken to ensure that the RBW and VBW used meet
the regulatory requirements, and that the EBW of the DUT is not reduced. The Photographs included in
this report show the DUT on the OATS.

5.3 Radiated Field Computations
To convert the dBm values 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   =   duty correction factor, dB
            CF   =   distance conversion (employed only if limits are specified at alternate distance), dB

        When presenting the data at each frequency, the highest measured emission under all of the
possible DUT orientations (3-axes) is given.

5.4 Indoor Power Line Conducted Emissions
When applicable, power line conducted emissions are measured in our semi-anechoic chamber. If the
DUT connects to auxiliary equipment and is table or floor standing, the configurations prescribed in
ANSI C63.4 are employed. Alternatively, an on-table layout more representative of actual use may be
employed if the resulting emissions appear to be worst-case in such a configuration.
       The conducted emissions measured with the spectrum analyzer and recorded (in dBµV) from 0-2
MHz and 2-30 MHz for both the ungrounded (Hi) and grounded (Lo) conductors. The spectrum analyzer
                                                Page 6 of 6


                             University of Michigan Radiation Laboratory
                       FCC Part 15, IC RSS-210/Gen - Test Report No. 417124-497

is set to peak-hold mode in order to record the highest peak throughout the course of functional operation.
Only when the emission exceeds or is near the limit are quasi-peak and average detection used.


5.5 Supply Voltage Variation
Measurements of the variation in the fundamental radiated emission were performed with the supply
voltage varied by no less than 85% and 115% of the nominal rated value. For battery operated equipment,
tests were performed using a new battery, and worst case emissions are re-checked employing a new
battery.

6. Test Results

6.1 Radiated Emissions

6.1.1 Correction for Pulse Operation
When the transmitter is activated (either by pressurization or by a single LF interrogation), it can, in the
worst case, transmit four 8.0 ms FSK words, any two of which may occur within a given 100 ms window.
When pressure activated the DUT will repeat this transmission every 210 seconds. See Figure 6.1.
Computing the duty factor results in:
                               KE = (2 x 8 ms) / 100 ms = 0.16 or -15.9 dB.

6.1.2 Emission Spectrum
The relative DUT emission spectrum is recorded and is shown in Figure 6.2.

6.1.3 Emission Bandwidth
The emission bandwidth of the signal is shown in Figure 6.3. The allowed 99% bandwidth is 0.25% of
315 MHz, or 787.25 kHz. From the plot we see that the EBW is 128.0 kHz, and the center frequency is
315 MHz.

6.1.4 Supply Voltage and Supply Voltage Variation
The DUT has been designed to be powered by a 3 VDC battery. For this test, relative radiated power was
measured at the fundamental as the voltage was varied from 2.0 to 4.0 volts. The emission variation is
shown in Figure 6.4.

          Batteries:    before testing          Voc =   3.3 V
                        after testing           Voc =   3.1 V
          Ave. current from batteries           I =     10.5 mA (cw)


6.2 Conducted Emissions
These tests do not apply, since the DUT is powered from a 3 VDC battery.


                                         The University of Michigan
                                           Radiation Laboratory
                                            3228 EECS Building
                                         Ann Arbor, MI 48109-2122
                                            Tel: (734) 764-0500
                                            Fax: (734) 647-2106



                                                Page 7 of 7


                              University of Michigan Radiation Laboratory
                        FCC Part 15, IC RSS-210/Gen - Test Report No. 417124-497



                                 Table 5.1 Highest Emissions Measured

                             Radiated Emission - RF                                   TRW HKMC TPMS; FCC/IC
       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    315.0   Dip     H     -22.3    Pk    18.6   21.6      65.8       67.7    1.9    flat
  2    315.0   Dip     V     -27.4    Pk    18.6   21.6      60.7       67.7    7.0    side
  3    630.0   Dip     H     -61.5    Pk    24.4   18.5      35.5       47.7   12.2    flat
  4    630.0   Dip     V     -60.9    Pk    24.4   18.5      36.1       47.7   11.6    end
  5    945.0   Dip     H     -63.1    Pk    28.8   16.5      40.3       47.7    7.3    flat
  6    945.0   Dip     V     -64.2    Pk    28.8   16.5      39.2       47.7    8.4    end
  7   1260.0   Horn    H     -33.5    Pk    20.6   28.1      50.1       54.0    3.9    flat
  8   1575.0   Horn    H     -52.9    Pk    21.5   28.1      31.6       54.0   22.4    flat
  9   1890.0   Horn    H     -46.5    Pk    22.2   28.1      38.7       54.0   15.3    side
10    2205.0   Horn    H     -53.7    Pk    23.0   26.5      33.9       54.0   20.0    side
11    2520.0   Horn    H     -65.6    Pk    23.9   26.0      23.4       54.0   30.6    flat
12    2835.0   Horn    H     -69.9    Pk    24.8   24.7      21.3       54.0   32.7    side
13    3150.0   Horn    H     -69.9    Pk    25.8   23.6      23.4       54.0   30.5    side
14
15
16
17
18                                          * Includes 15.9 dB duty factor
19
20
21
22
23
24
25
26
27
                                          Digital Radiated Emissions*
      Freq.    Ant. Ant.      Pr     Det.    Ka     Kg      E3      E3lim Pass                 Comments
#     kHz      Used Pol.     dBm     Used dB/m dB dBµV/m dBµV/m dB
1
2
3
4                          Digital emissions more than 20 dB below FCC/IC Class B Limit.
5
6
7
8
9 * For devices used in transportation vehicles, digital emissions are exempt from FCC regulations per FCC 15
                                                                                      Meas. 03/18/2009; U of Mich.


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                         University of Michigan Radiation Laboratory
                   FCC Part 15, IC RSS-210/Gen - Test Report No. 417124-497




Figure 6.1(a). Transmission modulation characteristics. (top) complete transmission, (center) expanded
                          transmission, (bottom) four words in transmission.



                                             Page 9 of 9


           University of Michigan Radiation Laboratory
     FCC Part 15, IC RSS-210/Gen - Test Report No. 417124-497




Figure 6.1(a). Transmission modulation characteristics. FSK word length.




      Figure 6.2. Emission spectrum of the DUT (pulsed emission).
            Amplitudes are only indicative (not calibrated).




                             Page 10 of 10


          University of Michigan Radiation Laboratory
    FCC Part 15, IC RSS-210/Gen - Test Report No. 417124-497




    Figure 6.3. Measured emission bandwidth of the DUT (pulsed).




Figure 6.4. Relative emission at fundamental vs. supply voltage (pulsed).




                             Page 11 of 11


                            University of Michigan Radiation Laboratory
                      FCC Part 15, IC RSS-210/Gen - Test Report No. 417124-497




Photograph 6.5. DUT on OATS (one of three axes tested)




Photograph 6.6. Close-up of DUT on OATS (one of three axes tested)




                                             Page 12 of 12



Document Created: 2009-04-13 10:00:14
Document Modified: 2009-04-13 10:00:14

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