test report

FCC ID: MRXG53MA4S

Test Report

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FCCID_1234826

                            University of Michigan Radiation Laboratory
                      FCC Part 15, IC RSS-210/Gen - Test Report No. 417124-549



                                       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

                          Schrader Electronics Limited Transmitter
                                 FCC ID: MRXG53MA4S
                                   IC: 2546A-G53MA4S

                                      Test Report No. 417124-549
                                            January 28, 2010

                                           Copyright © 2010

                                                 For:
                                     Schrader Electronics Limited
                                  11 Technology Park, Belfast Road,
                                  Antrim BT41 1QS, Northern Ireland
                                       Contact: Adrian Condon,
                                       acondon@schrader.co.uk
                                     Phone: +44 (0) 28 9448 3073
                                      Fax: +44 (0) 28 9446 8440


                                                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 Schrader, FCC ID: MRXG53MA4S, IC: 2546A-G53MA4S. This device under test
(DUT) is subject to the rules and regulations as a Transmitter.
        In testing completed on January 28, 2010, the DUT tested met the allowed specifications for
radiated emissions by 04 dB. Conducted emissions are not subject to regulation as the DUT is powered
by a 3 VDC battery.




                                               Page 1 of 14


                                 University of Michigan Radiation Laboratory
                           FCC Part 15, IC RSS-210/Gen - Test Report No. 417124-549



                                                       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 14


                            University of Michigan Radiation Laboratory
                      FCC Part 15, IC RSS-210/Gen - Test Report No. 417124-549

1. Introduction

This Schrader 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 14


                             University of Michigan Radiation Laboratory
                       FCC Part 15, IC RSS-210/Gen - Test Report No. 417124-549

3. Device Under Test

3.1 Description & Block Diagram
The transmitter operates at a single frequency between 314.900 MHz and 314.975 MHz. It is designed
for automotive/vehicular applications, sending tire pressure and temperature information to an onboard
receiver. The DUT is powered by a 3 VDC lithium battery and is housed in a plastic case approximately
5.5 x 7.5 x 1.5 cm in dimension. It is potted and permanently affixed in the wheel of a tire. The DUT is
designed and manufactured by Schrader Electronics Limited, 11 Technology Park, Belfast Road, Antrim
BT41 1QS, Northern Ireland.

 Equipment Used
 Device               [Make], Model                [S/N],P/N                  EMC Consideration
 DUT                  [Schrader], G53MA4S          Tx #1 (314.900 MHz)        15.231(e) / RSS-210 2.7 T5
 DUT                  [Schrader], G53MA4S          Tx #2 (314.900 MHz)        15.231(e) / RSS-210 2.7 T5
 DUT                  [Schrader], G53MA4S          Tx #3 (314.975 MHz)        15.231(e) / RSS-210 2.7 T5
 DUT                  [Schrader], G53MA4S          Tx #4 (314.975 MHz)        15.231(e) / RSS-210 2.7 T5
 DUT                  [Schrader], G53MA4S          Tx #A (314.900 MHz)        un-potted for photos


3.2 Variants & Samples
There is only a single variant of this device, but it can be programmed to operate by the manufacturer at a
specific frequency between 314.900 and 314.975 MHz. Five samples were provided for testing, one
normal sample at 314.900 MHz, one sample capable of CW transmission at 314.900 MHz, one normal
sample at 314.975 MHz, one sample capable of CW transmission at 314.975 MHz, , and one un-potted
sample for photographs and voltage variation.

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

3.4 Description of Operation exhibit. 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 14


                             University of Michigan Radiation Laboratory
                       FCC Part 15, IC RSS-210/Gen - Test Report No. 417124-549

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 14


                             University of Michigan Radiation Laboratory
                       FCC Part 15, IC RSS-210/Gen - Test Report No. 417124-549

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 and/or photographs. 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 intentional carriers are recorded. Receiver spurious emissions are measured
with an appropriate carrier signal applied. Associated test 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, when applicable. 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. Receiver spurious emissions are measured with
an appropriate carrier signal applied. For devices with intentional emissions below 30 MHz, our shielded
loop antenna at a 1 meter receive height is used. 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 Test Setup.

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, dBm, 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.
                                                Page 6 of 14


                             University of Michigan Radiation Laboratory
                       FCC Part 15, IC RSS-210/Gen - Test Report No. 417124-549

          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
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 (by tire rotation or LF interrogation), it can, in the worst case, transmit
one 27.675 ms word in any given 100 ms window. Each word is Manchester encoded with and pulse
width of 123.2 us and a period of 238.0 us. See Figure 6.1. Computing the duty factor results in:

                   KE = (27.675 ms / 100 ms) x (123.2 us / 238.0 us) = 0.143 = -16.9 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, measured at the low and high ends of the
frequency band in question. The allowed 99% bandwidth is 0.25% of 314.900 MHz, or 787.25 kHz.
From the plot we see that the worst case EBW is 200.0 kHz

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 2.5 to 3.75 volts. The emission variation is
shown in Figure 6.4.

          Batteries:    before testing           Voc =   3.3 V
                        after testing            Voc =   3.03 V
          Ave. current from batteries            I =     1.4 mA (pulsed)

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 14


                                 University of Michigan Radiation Laboratory
                           FCC Part 15, IC RSS-210/Gen - Test Report No. 417124-549




                                     Table 6.1 Highest Emissions Measured

                                             Radiated Emission - RF                            Schrader TPM Tx (#3); 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
       315.0
           0   Di
               Dip       H      -29.9
                                 29 9     Pk      18 6
                                                  18.6     21
                                                           21.8
                                                              8      56
                                                                     56.9
                                                                        9         67.7
                                                                                  67 7       10.7
                                                                                             10 7    flat
                                                                                                     fl t
  2    315.0   Dip       V      -28.6     Pk      18.6     21.8      58.2         67.7        9.4    end
  3    630.0   Dip       H      -62.0     Pk      24.4     18.8      33.7         47.7       13.9    flat
  4    630.0   Dip       V      -61.0     Pk      24.4     18.8      34.7         47.7       12.9    end
  5    945.0   Dip       H      -54.4     Pk      28.3     16.7      47.3         47.7        0.4    flat
  6    945.0   Dip       V      -54.7     Pk      28.3     16.7      47.0         47.7        0.7    end
  7   1260.0   Horn      H      -34.1     Pk      20.6     28.1      48.5         54.0        5.5    flat
  8   1575.0   Horn      H      -34.3     Pk      21.5     28.1      49.2         54.0        4.8    end
  9   1890.0   Horn      H      -49.2     Pk      22.2     28.1      35.0         54.0       19.0    end
10    2205.0   Horn      H      -57.6     Pk      23.0     26.5      29.0         54.0       24.9    flat
11    2520.0   Horn      H      -57.4     Pk      23.9     26.0      30.6         54.0       23.4    flat
12    2835.0   Horn      H      -65.0     Pk      24.8     24.7      25.2         54.0       28.8    side
13    3150.0   Horn      H      -70.3     Pk      25.8     23.6      22.0         54.0       31.9    flat
14
15
16
17
18
19
20
21
22
23
24                                                 * Includes 16.9 dB duty factor
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.    Limit
5
6
7
8
9 * For devices used in transportation vehicles, digital emissions are exempt from FCC regulations per FCC 15.103(a)
                                                                                                    Meas. 01/28/2010; U of Mich.

                                                     Page 8 of 14


      University of Michigan Radiation Laboratory
FCC Part 15, IC RSS-210/Gen - Test Report No. 417124-549




    Figure 6.1(a). Roll-mode modulation characteristics.
(top) repeated transmission, (bottom) expanded transmission




                       Page 9 of 14


      University of Michigan Radiation Laboratory
FCC Part 15, IC RSS-210/Gen - Test Report No. 417124-549




   Figure 6.1(b). LF activated modulation characteristics.
(top) complete transmission, (bottom) expanded transmission




                       Page 10 of 14


                         University of Michigan Radiation Laboratory
                   FCC Part 15, IC RSS-210/Gen - Test Report No. 417124-549




Figure 6.1(c). Word modulation characteristics. (top) complete word, (center) Manchester pulse period,
                                 (bottom) Manchester pulse width.

                                            Page 11 of 14


                            University of Michigan Radiation Laboratory
                      FCC Part 15, IC RSS-210/Gen - Test Report No. 417124-549




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




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


                                               Page 12 of 14


          University of Michigan Radiation Laboratory
    FCC Part 15, IC RSS-210/Gen - Test Report No. 417124-549




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




                             Page 13 of 14


                            University of Michigan Radiation Laboratory
                      FCC Part 15, IC RSS-210/Gen - Test Report No. 417124-549




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 14 of 14



Document Created: 2010-01-28 14:04:12
Document Modified: 2010-01-28 14:04:12

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