MPE Calculation

FCC ID:

RF Exposure Info

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                                                                                             REPORT No.:TRRFCC19-0029


RF EXPOSURE
1. Test Configuration
For devices designed for typical desktop applications, such a wireless charging pads, RF exposure evaluation should be
conducted assuming a user separation distance of 15 cm. E and H field strength measurements or numerical modeling may
be used to demonstrate compliance. Measurements should be made from all sides and the top of the primary/client pair,
with the 15 cm measured from the center of the probe(s) to the edge of the device. Emissions between 100 kHz to 300 kHz
should be assessed versus the limits at 300 kHz in Table 1 of Section 1.1310: 614 V/m and 1.63 A/m. A KDB inquiry is
required to determine the applicable exposure limits below 100 kHz.




2. Limit
Table 1—Limits for Maximum Permissible Exposure (MPE)

      Frequency Range          Electric field         Magnetic field       Power density          Averaging time
           (MHz)              strength (V/m)          Strength (A/m)        (mW/cm2)                (minutes)


                                     (A) Limits for Occupational/Controlled Exposure

            0.3 ~ 3.0               614                    1.63                  *100                    6

            3.0 ~ 30               1842/f                 4.89/f                *900/f2                  6

            30 ~ 300               61.4                   0.163                  1.0                     6

           300 ~1,500                                                            f/300                   6

       1,500 ~ 100,000                                                            5                      6

                                (B) Limits for General Population/Uncontrolled Exposure

           0.3 ~ 1.34               614                    1.63                  *100                    30

            1.34 ~ 30              824/f                  2.19/f                *180/f2                  30

            30 ~ 300               27.5                   0.073                  0.2                     30

           300 ~ 1,500                                                          f/1500                   30

       1,500 ~ 100,000                                                            1                      30

Note f = frequency in MHz * = Plane-wave equivalent power density

Per the guidance of KDB 680106, the E-field and H-field limits shown in the table above are extended down to
100kHz.




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                                                                                                    REPORT No.:TRRFCC19-0029

3. Equipment Approval Considerations
(1) Power transfer frequency is less than 1 MHz.
-The power transfer frequency is set from 110 kHz to 205 kHz. Therefore the frequency specification is satisfied with
the device.

(2) Output power from each primary coil is less than or equal to 15 watts.
-it is that supports up to 5 W

(3) The transfer system includes only single primary and secondary coils. This includes charging systems that may
have multiple primary coils and clients that are able to detect and allow coupling only between individual pairs of
coils.
-The DUT(Device Under Test) includes only one coil in transmitter.

(4) Client device is placed directly in contact with the transmitter.
-When the client device is placed directly in contact with transmitter, then charging is able to start.

(5) Mobile exposure conditions only (portable exposure conditions are not covered by this exclusion).
-Yes

(6) The aggregate H-field strengths at 15 cm surrounding the device and 20 cm above the top surface from all
simultaneous transmitting coils are demonstrated to be less than 50% of the MPE limit
-Yes (refer to 3page)



4. Test Methods
4.1 Measurement procedure
1. The RF exposure test was performed at the turn table of anechoic chamber.
2. The edge of the charger(EUT) and center of the filed probe should be located at specified distance(15 cm, 20
cm).
3. Maximum value of E-field and H-field were measured for the six side each at the specified distance and
recorded them on the following Test Result table. Six sides are [A]Front, [B]Left, [C]Rear, [D]Right, [E]Bottom and
[F]Top. Please see below diagram.
4. The EUT was implemented by the dictates of KDB 680106D01v03 accordingly.




4.2 Test diagram

                                                          F
                                                                           C


                                 D                                                     B
                                                     EUT
                                             A
                                                         E




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                                                                                                                 REPORT No.:TRRFCC19-0029

4.3 Test mode
In order to check all kinds of possible configurations, EUT was evaluated with appropriate client and under each charging
condition as below table.
                                EUT Voltage                                        Cal.Date
                                                                        Battery less than 1% charged
                             5 V Charging Mode                          Battery less than 50% charged
                                                                         Battery 100% fully charged

             * EUT has been tested with bottle as supporting equipment since the EUT has ability to charge only the specified tumbler.




4.4. Test Result
Comply (measurement data : refer to below)

- 5 V Charging Mode (Battery less than 1% charged)

E-field Measurements (Distance : 15 cm)
      Front           Left             Rear                         Right                Bottom                  Top
                                                                                                                                         Limit
       [A]            [B]               [C]                          [D]                   [E]                   [F]
                                                                                                                                         (V/m)
      (V/m)          (V/m)            (V/m)                         (V/m)                 (V/m)                 (V/m)
      0.69                0.71                  0.70                 0.67                  0.76                  0.68                614.00


E-field Measurements (Distance : 20 cm)
      Front           Left             Rear                         Right                Bottom                  Top
                                                                                                                                         Limit
       [A]            [B]               [C]                          [D]                   [E]                   [F]
                                                                                                                                         (V/m)
      (V/m)          (V/m)            (V/m)                         (V/m)                 (V/m)                 (V/m)
                                                                                                                 0.60                307.00


H-field Measurements (Distance : 15 cm)
     Front            Left             Rear                         Right                Bottom                  Top
                                                                                                                                         Limit
       [A]            [B]               [C]                          [D]                   [E]                   [F]
                                                                                                                                         (A/m)
     (A/m)           (A/m)            (A/m)                         (A/m)                 (A/m)                 (A/m)
      0.04                0.04                  0.05                 0.04                  0.04                  0.03                    1.63


H-field Measurements (Distance : 20 cm)
     Front            Left             Rear                         Right                Bottom                  Top
                                                                                                                                         Limit
       [A]            [B]               [C]                          [D]                   [E]                   [F]
                                                                                                                                         (A/m)
     (A/m)           (A/m)            (A/m)                         (A/m)                 (A/m)                 (A/m)
                                                                                                                 0.03                    0.82


- 5 V Charging Mode (Battery less than 50% charged)

E-field Measurements (Distance : 15 cm)
      Front           Left             Rear                         Right                Bottom                  Top
                                                                                                                                         Limit
       [A]            [B]               [C]                          [D]                   [E]                   [F]
                                                                                                                                         (V/m)
      (V/m)          (V/m)            (V/m)                         (V/m)                 (V/m)                 (V/m)
      0.71                0.70                  0.72                 0.68                  0.77                  0.66                614.00




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                                                                               REPORT No.:TRRFCC19-0029

E-field Measurements (Distance : 20 cm)
      Front           Left             Rear           Right           Bottom    Top
                                                                                           Limit
       [A]            [B]               [C]            [D]              [E]     [F]
                                                                                           (V/m)
      (V/m)          (V/m)            (V/m)           (V/m)            (V/m)   (V/m)
                                                                               0.59       307.00


H-field Measurements (Distance : 15 cm)
     Front            Left             Rear           Right           Bottom    Top
                                                                                           Limit
       [A]            [B]               [C]            [D]              [E]     [F]
                                                                                           (A/m)
     (A/m)           (A/m)            (A/m)           (A/m)            (A/m)   (A/m)
      0.04            0.04             0.04            0.04            0.04    0.03        1.63


H-field Measurements (Distance : 20 cm)
     Front            Left             Rear           Right           Bottom    Top
                                                                                           Limit
       [A]            [B]               [C]            [D]              [E]     [F]
                                                                                           (A/m)
     (A/m)           (A/m)            (A/m)           (A/m)            (A/m)   (A/m)
                                                                               0.03        0.82


- 5 V Charging Mode (Battery 100% fully charged)

E-field Measurements (Distance : 15 cm)
      Front           Left             Rear           Right           Bottom    Top
                                                                                           Limit
       [A]            [B]               [C]            [D]              [E]     [F]
                                                                                           (V/m)
      (V/m)          (V/m)            (V/m)           (V/m)            (V/m)   (V/m)
      0.72            0.71             0.71            0.70            0.74    0.65       614.00


E-field Measurements (Distance : 20 cm)
     Front            Left             Rear           Right           Bottom    Top
                                                                                           Limit
       [A]            [B]               [C]            [D]              [E]     [F]
                                                                                           (V/m)
      (V/m)          (V/m)            (V/m)           (V/m)            (V/m)   (V/m)
                                                                               0.60       307.00


H-field Measurements (Distance : 15 cm)
     Front            Left             Rear           Right           Bottom    Top
                                                                                           Limit
       [A]            [B]               [C]            [D]              [E]     [F]
                                                                                           (A/m)
     (A/m)           (A/m)            (A/m)           (A/m)            (A/m)   (A/m)
      0.04            0.04             0.04            0.04            0.04    0.03        1.63


H-field Measurements (Distance : 20 cm)
     Front            Left             Rear           Right           Bottom    Top
                                                                                           Limit
       [A]            [B]               [C]            [D]              [E]     [F]
                                                                                           (A/m)
     (A/m)           (A/m)            (A/m)           (A/m)            (A/m)   (A/m)
                                                                               0.03        0.82




                                           Copyright ⓒ 2019. Lab-T, Inc.                    Page :4 / 5


                                                                                       REPORT No.:TRRFCC19-0029

5 Test Equipment
         Type              Manufacturer      Model            Cal.Date    Next.Cal.Date       S/N

      EMF Tester           WaveControl       SMP2             19.01.16      21.01.16        17SN0599

Isotropic Electric Field
                           ETS-Lindgren     HI-6105           19.06.05      20.06.05         161805
         Probe
Isotropic Electric Field
                           ETS-Lindgren     HI-6113              -              -            161970
       Interface




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Document Created: 2019-09-11 13:19:37
Document Modified: 2019-09-11 13:19:37

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