Test report

FCC ID: GQ4-32T

Test Report

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                        University of Michigan Radiation Laboratory
                  FCC Part 15, IC RSS-210/Gen - Test Report No. 415031-310



                                     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(s):      42607-0C030 (20 degree bend),
                                      42607-0C040 (40 degree bend)

                                       Report No. 415031-310
                                           June 26, 2006

                                          Copyright © 2006

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

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



                                                 Tests supervised by:
Measurements made by:                            Report approved by: _____________________
                           Valdis V. Liepa                               Valdis V. Liepa
                                                                         Research Scientist


Summary

Tests for compliance with FCC Regulations Part 15, Subpart C, and Industry Canada RSS-210, were
performed on TRW model(s) 42607-0C030 (20 degree), 42607-0C040 (40 degree). This device is subject
to the Rules and Regulations as a Transmitter.
        In testing completed on June 21, 2006, the device tested in the worst case met the allowed FCC
specifications for radiated emissions by 2.8 dB (see p. 6). Besides harmonics, there were no other
significant spurious emissions found; emissions from digital circuitry were negligible. The
conducted emission tests do not apply, since the device is powered from a 12 VDC battery.



                                             Page 1 of 10


                         University of Michigan Radiation Laboratory
                   FCC Part 15, IC RSS-210/Gen - Test Report No. 415031-310

1. Introduction

TRW model 42607-0C030 (20 degree), 42607-0C040 (40 degree) 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 6, September 2005. The 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 2057).

2. Test Procedure 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)                           EMCO 6502, SN:2855
Ridge-horn Antenna (300-5000 MHz)                X           University of Michigan
Amplifier (5-1000 MHz)                           X           Avantak, A11-1, A25-1S
Amplifier (5-4500 MHz)                           X           Avantak
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

                                             Page 2 of 10


                         University of Michigan Radiation Laboratory
                   FCC Part 15, IC RSS-210/Gen - Test Report No. 415031-310

3. Configuration and Identification of Device Under Test

The DUT is a 315 MHz TPMS, Tire Pressure Monitor Sensor (transmitter), 2.5 x 0.75 x 3 inches in size,
and is FSK modulated. The transmitter consists of an RF MMIC that is stabilized by a 9.84 MHz crystal.
The stem and PCB are used as the antenna. The DUT periodically transmits tire pressure data and is
subject to FCC part 15.231(e) emissions limits. The device is also capable of being automatically
actuated (via LF interrogation) by trained service personnel, and (per FCC correspondence) those modes
fall under FCC part 15.231(a)(5). The DUT was designed and manufactured by TRW, 24175 Research
Drive, Farmington Hills, MI 48335-2642. It is identified as:

                          TRW TPMS Transmitter
                          Model(s): 42607-0C030, 42607-0C040
                          FCC ID: GQ4-32T
                          IC: 1470A-13

There are two versions of the DUT, one with a 20 degree bend between the tire stem and the PCB and one
with a 40 degree bend between the stem and the PCB. All electronic components are identical. The DUT
with the 20 degree stem demonstrated the highest fundamental output power, and was fully tested. The
worst case emissions from the other model are reported. Figure 6.1 demonstrates compliance with
15.231(a)(2) and (5); the transmission protocol in both modes is the same.

3.1 Modifications Made
There were no modifications made to the DUT by this laboratory.

4. Emission Limits

The DUT tested falls under the category of an Intentional Radiators and the Digital Devices. For FCC, it
is subject to Part 15, Subpart C, (Section 15.231), Subpart B, (Section 15.109), and Subpart A, (Section
15.33). For Industry Canada it is subject to RSS-210, (Sections 6.1 and 6.3). The applicable testing
frequencies with corresponding emission limits are given in Tables 4.1 and 4.2 below. As a digital
device, the DUT is considered as a Class B device.

4.1 Radiated Emission Limits

        Table 4.1. 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)




                                             Page 3 of 10


                         University of Michigan Radiation Laboratory
                   FCC Part 15, IC RSS-210/Gen - Test Report No. 415031-310


      Table 4.2. Radiated Emission Limits (FCC: 15.231(e), 15.205(a); IC: RSS-210; 2.7 Table 5).
                                            (Transmitter)

                                      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             2418             67.7          241.8           47.7
            322-335.4
                               Restricted
            399.9-410                                             200            46.0
                                 Bands
              608-614
             960-1240
            1300-1427
           1435-1626.5         Restricted
                                                                  500            54.0
            1660-1710            Bands
          1718.9-1722.2
            2200-2300
        * Linear interpolation, formula: E = -2833.2 + 16.67*f (MHz)
       ** Measure up to tenth harmonic; 120 kHz RBW up to 1 GHz, 1 MHz RBW above 1 GHz

4.3 Conducted Emissions Limits
The conductive emission limits and tests do not apply here, since the DUT is powered by a 12 VDC
battery.

5. Radiated Emission Tests and Results

5.1 Semi-Anechoic Chamber Measurements
To familiarize with the radiated emission behavior of the DUT, the DUT was first studied and measured
in a 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.
         In testing for radiated emissions, a transmitter was provided by the manufacturer that is capable
of repeated pulse emissions. It was placed on the test table flat, on its side, or on its end.
         In the chamber we studied and recorded all the emissions using a Bicone antenna up to 300 MHz
and a ridged horn antenna above 200 MHz. The measurements made in the chamber below 1 GHz are
used for pre-test evaluation only. The measurements made above 1 GHz are used in pre-test evaluation
and in the final compliance assessment. We note that for the horn antenna, the antenna pattern is more
directive and hence the measurement is essentially that of free space (no ground reflection).
Consequently it is not essential to measure the DUT for both antenna polarizations, as long as the DUT is
measured on all three of its major axis. In the chamber we also recorded the spectrum and modulation
characteristics of the carrier. These data are presented in subsequent sections. We also note that in
scanning from 30 MHz to 4.5 GHz using Bicone and the ridge horn antennas, there were no other
significant spurious emissions observed.




                                              Page 4 of 10


                          University of Michigan Radiation Laboratory
                    FCC Part 15, IC RSS-210/Gen - Test Report No. 415031-310

5.2 Open Site Radiated Emission Tests
After the chamber measurements, the emissions were re-measured on the outdoor 3-meter site at
fundamental and harmonics up to 1 GHz using tuned dipoles and/or the high frequency Bicone.
Photographs included in this filing show the DUT on the Open Area Test Site (OATS).

5.3 Computations and Results for Radiated Emissions
To convert the dBm's measured on the spectrum analyzer to dB(µV/m), we use expression

                                   E3(dBµV/m) = 107 + PR+ KA – KG

where       PR =     power recorded on spectrum analyzer, dB, measured at 3m
            KA =     antenna factor, dB/m
            KG =     pre-amplifier gain, including cable loss, 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 the
DUT meets the limit by 2.8 dB.

5.4 Conducted Emission Tests
These tests do not apply, since the DUT is powered from a 12 VDC battery.

6. Other Measurements

6.1 Correction For Pulse Operation
When the transmitter is activated (either by LF pulse or motion), it can, in the worst case, transmit two
7.95 ms pulses of encoded FSK data in any given 100 ms window. See Figure 6.1. Computing the duty
factor results in:
                             KE = (2 x 7.95 ms) / 100 ms = 0.159 or -16.0 dB.

6.2 Emission Spectrum
Using the ridge-horn antenna and DUT placed in its aperture, 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. The allowed (-20 dB) bandwidth is 0.25%
of MHz, or 787.25 kHz. From the plot we see that the -20 dB bandwidth is 133 kHz, and the center
frequency is 315 MHz.

6.4 Effect of Supply Voltage Variation
The DUT has been designed to be powered by a 12 VDC battery. For this test, the battery was replaced
by a laboratory variable power supply. Relative power radiated was measured at the fundamental as the
voltage was varied from 2 to 4 volts. The emission variation is shown in Figure 6.4.

6.5 Input Voltage at Battery Terminals
          Batteries:    before testing         Voc =    3.2 V
                        after testing          Voc =    3.0 V
          Ave. current from batteries          I =      8.5 mA (cw)




                                               Page 5 of 10


                                 University of Michigan Radiation Laboratory
                           FCC Part 15, IC RSS-210/Gen - Test Report No. 415031-310

                                  Table 5.1 Highest Emissions Measured

                                        Radiated Emission - RF                          TRW Toyota TPM; 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      -28.1    Pk    18.9    22.6     59.2       67.7     8.5   flat (20 deg. stem)
  2    315.0   Dip     V      -33.1    Pk    18.9    22.6     54.2       67.7    13.5   end
  3    630.0   Dip     H      -58.9    Pk    25.2    19.6     37.7       47.7    10.0   flat
  4    630.0   Dip     V      -56.8    Pk    25.2    19.6     39.8       47.7     7.9   end
  5    945.0   Dip     H      -74.3    Pk    28.9    17.7     27.9       47.7    19.8   flat
  6    945.0   Dip     V      -74.2    Pk    28.9    17.7     28.0       47.7    19.7   end
  7   1260.0   Horn    H      -44.7    Pk    20.6    28.0     38.9       54.0    15.1   flat
  8   1575.0   Horn    H      -42.7    Pk    21.5    28.0     41.8       54.0    12.2   end
  9   1890.0   Horn    H      -34.1    Pk    22.2    28.0     51.1       54.0     2.9   flat
10    2205.0   Horn    H      -39.3    Pk    23.0    28.1     46.6       54.0     7.4   end
11    2520.0   Horn    H      -41.4    Pk    23.9    28.3     45.2       54.0     8.8   flat
12    2835.0   Horn    H      -54.1    Pk    24.8    28.2     33.5       54.0    20.5   flat
13    3150.0   Horn    H      -59.2    Pk    25.8    27.9     29.7       54.0    24.3   flat
14
15
16
17    1890.0   Horn    H      -34.0   Pk     22.2    28.0     51.2        54.0    2.8 flat (40 deg. stem)
18
19
20
21
22
23
24                                           * Includes 16.0 dB duty factor
25
26                           Digital emissions more than 20 dB below FCC/IC Class B Limit.
27



                                                    Conducted Emissions
      Freq.    Line   Det.   Vtest Vlim      Pass
#     MHz      Side   Used   dBµV dBµV        dB                      Comments

                                                     Not applicable




                                                                                   Meas. 05/05,10/2006; U of Mich.

                                                     Page 6 of 10


             University of Michigan Radiation Laboratory
       FCC Part 15, IC RSS-210/Gen - Test Report No. 415031-310




Figure 6.1. Transmissions modulation characteristics: (top) complete transmission,
            (bottom) expanded FSK word.




                                 Page 7 of 10


             University of Michigan Radiation Laboratory
       FCC Part 15, IC RSS-210/Gen - Test Report No. 415031-310




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




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




                              Page 8 of 10


                            University of Michigan Radiation Laboratory
                      FCC Part 15, IC RSS-210/Gen - Test Report No. 415031-310




                     2.00

                     1.00
Relative Amplitude




                     0.00

                     -1.00

                     -2.00

                     -3.00
                          2.0   2.3      2.5        2.8       3.0    3.3       3.5   3.8
                                                     Voltage (V)



Figure 6.4.                     Relative emission at 315.0 MHz vs. supply voltage
                                (cw emission).




                                               Page 9 of 10


      University of Michigan Radiation Laboratory
FCC Part 15, IC RSS-210/Gen - Test Report No. 415031-310




                                                           DUT on OATS




                                                  DUT on OATS (close-up)



                     Page 10 of 10



Document Created: 2006-06-26 21:20:48
Document Modified: 2006-06-26 21:20:48

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