SAR Simulation Report

FCC ID: AZ492FT7118

RF Exposure Info

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FCCID_3958119

FCC ID: AZ492FT7118 Report ID: P8878-EME-00003 COMPUTATIONAL EME COMPLIANCE ASSESSMENT OF THE APX SERIES MODEL M37TXS9PW1AN (HUW1001A) MOBILE RADIO. July 03, 2018 Saw Sun Hock, Giorgi Bit-Babik, Ph.D., and Antonio Faraone, Ph.D. Motorola Solutions EME Research Lab, Plantation, Florida Introduction This report summarizes the computational [numerical modeling] analysis performed to document compliance of the APX Series Model Number M37TXS9PW1AN (HUW1001A) Mobile Radio and vehicle-mounted antennas with the US Federal Communications Commission (FCC) guidelines for human exposure to radio frequency (RF) emissions. The radio operates in the following frequency bands: Bands Frequency Band (MHz) LMR VHF 150.8 - 173.4 LMR UHF1 406.1 - 470 LMR UHF2 450 - 512 LMR 7/800 769-775; 799-824; 851-869 This computational analysis supplements the measurements conducted to evaluate the compliance of the exposure from this mobile radio with respect to applicable maximum permissible exposure (MPE) limits. All test conditions (47 in total) that did not conform with applicable MPE limits were analyzed to determine whether those conditions complied with the specific absorption rate (SAR) limits for general public exposure (1.6 W/kg averaged over 1 gram of tissue and 0.08 W/kg averaged over the whole body) set forth in FCC guidelines, which are based on the IEEE C95.1-1999 standard [1]. 1

FCC ID: AZ492FT7118 Report ID: P8878-EME-00003 With SAR simulation reduction considerations, total 44 independent simulations had been performed addressing exposure of passenger and bystander to the VHF mobile radio with roof-mount antennas. For all simulations a commercial code based on Finite-Difference-Time-Domain (FDTD) methodology was employed to carry out the computational analysis. It is well established and recognized within the scientific community that SAR is the primary dosimetric quantity used to evaluate the human body’s absorption of RF energy and that MPE limits are in fact derived from SAR. Accordingly, the SAR computations provide a scientifically valid and more relevant estimate of human exposure to RF energy. Method The simulation code employed is XFDTD™ v7.6.0, by Remcom Inc., State College, PA. This computational suite provides means to simulate the heterogeneous full human body model defined according to the IEC/IEEE 62704-2-2017 standard and derived from the so-called Visible Human [2], discretized in 3 mm voxels. The IEC/IEEE 62704-2-2017 standard dielectric properties of 39 body tissues are automatically assigned by XFDTD™ at any specific frequency. The “seated” man model was obtained from the standing model by modifying the articulation angles at the hips and the knees. Details of the computational method and model are provided in the Appendix A to this report. The evaluation of the computational uncertainties and results of the benchmark validations are provided in the Appendix B attached to this report. The XFDTD code validation performed according to IEEE/IEC 62704-1:2017 standard by Remcom Inc. is provided in conjunction with this report. The car model has been imported into XFDTD™ from the CAD file of a sedan car having dimensions 4.98 m (L) x 1.85 m (W) x 1.18 m (H), and discretized with the minimum resolution of 3 mm and the maximum resolution of 8 mm. The Figure 1 below shows both the CAD model and the photo of the actual car. This CAD model has been incorporated into the IEC/IEEE 62704-2-2017 standard. 2

FCC ID: AZ492FT7118 Report ID: P8878-EME-00003 Figure 1: The photo picture of the car and the corresponding CAD model used in simulations Figure 2 shows some of the XFDTD™ computational models used for passenger exposure to roof mounted antennas. For bystander exposure, the antenna position is at the side of the roof with separation distance 90 cm from antenna. Figure 3 shows some for the XFDTD™ computational models used for bystander exposure configurations. According to the IEC/IEEE 62704-2-2017 for exposure simulations from vehicle mount antennas the lossy dielectric slab with 30 cm thickness, dielectric constant of 8 and conductivity of 0.01 S/m has been introduced in the computational model to properly account for the effect of the ground (pavement) on exposure. 3

FCC ID: AZ492FT7118 Report ID: P8878-EME-00003 Figure 2: Passenger model exposed to a roof-mount antenna Figure 3: Bystander model exposed to a roof-mount antenna 4

FCC ID: AZ492FT7118 Report ID: P8878-EME-00003 The computational code employs a time-harmonic excitation to produce a steady state electromagnetic field in the exposed body. Subsequently, the corresponding SAR distribution is automatically processed in order to determine the whole-body and 1-g average SAR. The maximum average output power from mobile radio antenna is 120W (136-174MHz). Since the ohmic losses in the car materials, as well as the mismatch losses at the antenna feed-point are neglected, and source-based time averaging (50% talk time) were employed, all computational results are normalized to half of it, i.e., 60W (136-174MHz) average net output power; less the corresponding minimum insertion loss in excess of 0.5 dB of the feed cables supplied with the antennas. This power normalization is in accordance with the IEC/IEEE 62704-2-2017. Results of SAR computations for car passengers and bystanders The test conditions requiring SAR computations are summarized in Table 1 (Bystanders) and Table 2 (Passengers) together with the antenna data, the SAR results, and power density (P.D.) as obtained from the measurements in the corresponding test conditions. The conditions are for antennas mounted on the roof. The antenna length in tables includes the 1.8 cm magnetic mount base used in measurements to position the antenna on the vehicle. The same length was used in simulation model. The passenger is located in the center or on the side of the rear seat corresponding to the respective configurations defined in the IEC/IEEE 62704-2-2017 standard. The bystander is located at the measurement distance from the transmit antenna as described in the MPE report and is assessed separately for front and back (rear) exposure. All the transmit frequency, antenna length, and passenger/bystander location combinations reported in Table 1 and Table 2 have been simulated individually. These tables also include the interpolated adjustment factor and corresponding SAR scaled values following requirement of the IEC/IEEE 62704-2-2017 standard. 5

FCC ID: AZ492FT7118 Report ID: P8878-EME-00003 Table 1: Results of the Computations and Adjusted SAR for Bystanders exposure Interpolated Mount Antenna Computations Adjusted SAR Antenna Kit# Freq P.D. Adjustment Length Exposure Location SAR (W/kg) Results (W/kg) Location (MHz) (mW/cm^2) Factors (cm) 1g WB 1g WB 1g WB AN000131A01, Front 0.43 0.020 1.29 1.80 0.55 0.037 Roof 1/4 wave (136- 57.5 150.8000 0.33 870MHz)1 Rear 0.38 0.020 1.29 1.80 0.49 0.036 *RAD4010ARB, Front 0.28 0.010 1.32 1.80 0.36 0.018 Roof 1/2 Wave 105.5 173.0125 0.25 (136-174MHz) Rear 0.39 0.011 1.32 1.80 0.52 0.019 *RAD4010ARB, Front 0.15 0.006 1.30 1.80 0.19 0.010 Roof 1/2 Wave 114.3 158.0125 0.20 (136-174MHz) Rear 0.18 0.006 1.30 1.80 0.24 0.011 *RAD4010ARB, Front 0.14 0.005 1.29 1.80 0.18 0.009 Roof 1/2 Wave 128.6 150.8000 0.20 (136-174MHz) Rear 0.14 0.006 1.29 1.80 0.19 0.010 *HAD4022A, Front 0.44 0.018 1.32 1.80 0.58 0.033 Roof 5/8 Wave (132- 91.7 173.0125 0.30 174MHz) Rear 0.71 0.019 1.32 1.80 0.94 0.034 *HAD4022A, Front 0.28 0.013 1.31 1.80 0.37 0.023 Roof 5/8 Wave (132- 98.3 165.0125 0.23 174MHz) Rear 0.48 0.013 1.31 1.80 0.63 0.023 *HAD4022A, Front 0.21 0.010 1.30 1.80 0.27 0.017 Roof 5/8 Wave (132- 104.5 158.0125 0.22 174MHz) Rear 0.33 0.010 1.30 1.80 0.43 0.018 *HAD4022A, Front 0.21 0.009 1.29 1.80 0.28 0.017 Roof 5/8 Wave (132- 115.8 150.8000 0.22 174MHz) Rear 0.33 0.010 1.29 1.80 0.42 0.017 HAD4016A, 1/4 Front 0.42 0.020 1.29 1.80 0.54 0.035 Roof Wave (136- 53.1 150.8000 0.37 162MHz) Rear 0.38 0.019 1.29 1.80 0.49 0.035 HAD4017A, 1/4 Front 0.36 0.017 1.30 1.80 0.47 0.030 Roof Wave (146- 48.0 158.0125 0.34 174MHz) Rear 0.36 0.016 1.30 1.80 0.47 0.030 HAD4021A, 1/4 Front 0.42 0.020 1.29 1.80 0.54 0.035 Roof Wave (136- 53.5 150.8000 0.34 174MHz) Rear 0.38 0.019 1.29 1.80 0.49 0.035 HAD4007A, 1/4 Front 0.42 0.020 1.29 1.80 0.55 0.036 Roof Wave (144- 50.8 150.8000 0.41 150.8MHz) Rear 0.38 0.019 1.29 1.80 0.49 0.035 HAD4008A, 1/4 Front 0.37 0.016 1.30 1.80 0.48 0.030 Roof Wave (150.8- 47.3 156.4000 0.36 162MHz) Rear 0.37 0.016 1.30 1.80 0.48 0.029 Front 0.50 0.028 1.32 1.80 0.65 0.050 173.0125 0.32 Rear HAD4009A, 1/4 0.78 0.027 1.32 1.80 1.03 0.048 Roof 44.8 (Figure 4 & 5) Wave (162- 174MHz) Front 0.34 0.020 1.31 1.80 0.45 0.035 165.0125 0.31 Rear 0.50 0.020 1.31 1.80 0.66 0.035 Note: * Antenna length trimmed to frequency. Bold Blue – the highest SAR results computed for the respective frequency bands 6

FCC ID: AZ492FT7118 Report ID: P8878-EME-00003 Table 2: Results of the Computations and Adjusted SAR for Passenger exposure Interpolated Mount Antenna Computations Adjusted SAR Results Antenna Kit# Freq P.D. Adjustment Length Exposure Location SAR (W/kg) (W/kg) Location (MHz) (mW/cm^2) Factors (cm) 1g WB 1g WB 1g WB AN000131A01, Back Center 0.26 0.005 1.27 2.07 0.33 0.011 Roof 1/4 wave (136- 57.5 158.0125 0.37 Back Side 870MHz)1 0.56 0.005 1.02 1.53 0.57 0.008 (Figure 6 & 7) HAD4016A, 1/4 Back Center 0.06 0.003 1.31 2.11 0.08 0.006 Roof Wave (136- 53.1 162.0000 0.34 162MHz) Back Side 0.21 0.004 1.03 1.55 0.22 0.005 HAD4017A, 1/4 Back Center 0.05 0.003 1.34 2.14 0.07 0.006 Roof Wave (146- 48.0 165.0125 0.42 174MHz) Back Side 0.18 0.004 1.04 1.56 0.19 0.006 HAD4021A, 1/4 Back Center 0.17 0.004 1.27 2.07 0.21 0.009 Roof Wave (136- 53.5 158.0125 0.33 174MHz) Back Side 0.28 0.004 1.02 1.53 0.29 0.006 HAD4007A, 1/4 Back Center 0.25 0.006 1.21 2.01 0.30 0.013 Roof Wave (144- 50.8 150.8000 0.37 150.8MHz) Back Side 0.53 0.008 1.00 1.50 0.54 0.012 HAD4008A, 1/4 Back Center 0.06 0.003 1.31 2.11 0.08 0.006 Roof Wave (150.8- 47.3 162.0000 0.36 162MHz) Back Side 0.22 0.004 1.03 1.55 0.22 0.006 HAD4009A, 1/4 Back Center 0.05 0.003 1.34 2.14 0.07 0.006 Roof 44.8 Wave (162- 165.0125 0.35 174MHz) Back Side 0.18 0.004 1.04 1.56 0.19 0.006 Note: Bold Blue – the highest SAR results computed for the respective frequency bands 7

FCC ID: AZ492FT7118 Report ID: P8878-EME-00003 The SAR distribution in the bystander exposure condition that gave highest adjusted 1-g SAR is reported in Figure 4 (173.0125 MHz, bystander back (rear) at the side of the roof, HAD4009A antenna). Figure 4. SAR distribution at 173.0125 MHz in the bystander back (rear) located at the side of the roof, produced by roof-mounted antenna HAD4009A antenna. The contour plot for SAR distribution in the figure is relative to the plane where the peak 1-g average SAR for this exposure condition occurs. The two pictures below show the E and H field distributions in the plane of the antenna corresponding to the condition in Figure 4. a) 8

FCC ID: AZ492FT7118 Report ID: P8878-EME-00003 b) Figure 5. (a) E-field magnitude distribution corresponding to exposure condition of Figure 4, and (b) H-field magnitude distribution corresponding to exposure condition of Figure 4. The highest adjusted 1-g SAR was produced in the bystander exposure condition with HAD4009A antenna at 173.0125 MHz (bystander back at the side of the roof). 9

FCC ID: AZ492FT7118 Report ID: P8878-EME-00003 The SAR distribution in the passenger exposure condition that gave highest adjusted 1-g SAR is reported in Figure 6. (158.0125 MHz, passenger on the side of the back seat, AN000131A1 antenna). Figure 6. SAR distribution at 158.0125 MHz in the passenger model located on the side of the back seat, produced by the roof-mount AN000131A01 antenna. The contour plot is relative to the plane where the peak 1-g average SAR for this exposure condition occurs. 10

FCC ID: AZ492FT7118 Report ID: P8878-EME-00003 The pictures below show the E and H field distributions in the plane of the antenna corresponding to the condition in Figure 6. a) 11

FCC ID: AZ492FT7118 Report ID: P8878-EME-00003 b) Figure 7. (a) E-field magnitude distribution corresponding to exposure condition of Figure 6, and (b) H-field magnitude distribution corresponding to exposure condition of Figure 6. The highest adjusted 1-g SAR was produced in the passenger exposure condition with AN000131A01 antenna at 158.0125 MHz (passenger on the side of the back seat). 12

FCC ID: AZ492FT7118 Report ID: P8878-EME-00003 SAR Simulation Reduction Considerations Per Response to Inquiry to FCC (Tracking Number 528198), for a particular antenna that has more than one configuration which exceeds the MPE limit, SAR simulation shall begin with the worst case configuration (mount location and frequency channel). If the SAR value is less than 50% of the limit, no further SAR evaluation is needed for that antenna. If the worse case configuration SAR value is above 50% of the limit, SAR simulation shall be done on the subsequent worse configuration (ranked in descending MPE percentage to limit). If the subsequent SAR value is below 75% of the limit, no further SAR evaluation is needed for that antenna, otherwise the SAR simulations for the remaining antenna configurations shall continue until the SAR value is below 75% of the limit. Table 3 and Table 4 below list all the configurations that did not conform with applicable MPE limits (ranked in descending MPE percentage to limit) and apply SAR simulation reduction consideration as mentioned above. Table 3: SAR Simulation Reduction Considerations for Bystander % To Adjusted SAR Results Mount Freq P.D. FCC Limit FCC Exposure (W/kg) Antenna Kit# SAR Simulation Reduction Location (MHz) (mW/cm^2) (mW/cm^2) Spec Location 1g WB Limit Front 0.55 0.037 150.8000 0.33 0.20 167.1 Rear 0.49 0.036 Front NA NA The highest MPE configuration has AN000131A01, 158.0125 0.33 0.20 166.9 Roof Rear NA NA SAR below 50% of the limit. 1/4 wave (136- 870MHz) Front NA NA The highest MPE configuration has 173.0125 0.32 0.20 158.2 Rear NA NA SAR below 50% of the limit. Front NA NA The highest MPE configuration has 165.0125 0.26 0.20 129.3 Rear NA NA SAR below 50% of the limit. *RAD4010ARB, Front 0.36 0.018 Roof 1/2 Wave 173.0125 0.25 0.20 127.1 (136-174MHz) Rear 0.52 0.019 *RAD4010ARB, Front 0.19 0.010 Roof 1/2 Wave 158.0125 0.20 0.20 100.4 (136-174MHz) Rear 0.24 0.011 *RAD4010ARB, Front 0.18 0.009 Roof 1/2 Wave 150.8000 0.20 0.20 100.0 (136-174MHz) Rear 0.19 0.010 *HAD4022A, Front 0.58 0.033 Roof 173.0125 5/8 Wave (132- 0.30 0.20 148.8 174MHz) Rear 0.94 0.034 *HAD4022A, Front 0.37 0.023 Roof 5/8 Wave (132- 165.0125 0.23 0.20 114.2 174MHz) Rear 0.63 0.023 *HAD4022A, Front 0.27 0.017 Roof 5/8 Wave (132- 158.0125 0.22 0.20 110.9 174MHz) Rear 0.43 0.018 *HAD4022A, Front 0.28 0.017 Roof 150.8000 0.22 0.20 107.6 5/8 Wave (132- Rear 0.42 0.017 Note: * Antenna length trimmed to frequency. 13

FCC ID: AZ492FT7118 Report ID: P8878-EME-00003 Table 3 (Continued): SAR Simulation Reduction Considerations for Bystander % To Adjusted SAR Mount Freq P.D. FCC Limit FCC Exposure Results (W/kg) Antenna Kit# SAR Simulation Reduction Location (MHz) (mW/cm^2) (mW/cm^2) Spec Location 1g WB Limit Front 0.54 0.035 150.8000 0.37 0.20 187.4 Rear 0.49 0.035 HAD4016A, 1/4 Front NA NA Roof The highest MPE configuration Wave (136- 162.000 0.32 0.20 158.9 Rear NA NA has SAR below 50% of the limit. 162MHz) Front NA NA The highest MPE configuration 156.4000 0.31 0.20 156.0 Rear NA NA has SAR below 50% of the limit. Front 0.47 0.030 158.0125 0.34 0.20 168.8 Rear 0.47 0.030 Front NA NA The highest MPE configuration 173.0125 0.31 0.20 156.5 HAD4017A, 1/4 Rear NA NA has SAR below 50% of the limit. Roof Wave (146- 174MHz) Front NA NA The highest MPE configuration 165.0125 0.29 0.20 143.2 Rear NA NA has SAR below 50% of the limit. Front NA NA The highest MPE configuration 150.8000 0.25 0.20 122.6 Rear NA NA has SAR below 50% of the limit. Front 0.54 0.035 150.8000 0.34 0.20 168.0 Rear 0.49 0.035 Front NA NA The highest MPE configuration 158.0125 0.29 0.20 147.3 HAD4021A, 1/4 Rear NA NA has SAR below 50% of the limit. Roof Wave (136- 174MHz) Front NA NA The highest MPE configuration 165.0125 0.24 0.20 117.8 Rear NA NA has SAR below 50% of the limit. Front NA NA The highest MPE configuration 173.0125 0.22 0.20 109.8 Rear NA NA has SAR below 50% of the limit. HAD4007A, 1/4 Front 0.55 0.036 Roof Wave (144- 150.8000 0.41 0.20 202.8 150.8MHz) Rear 0.49 0.035 Front 0.48 0.030 156.4000 0.36 0.20 180.0 Rear 0.48 0.029 HAD4008A, 1/4 Front NA NA Roof The highest MPE configuration Wave (150.8- 162.0000 0.34 0.20 168.5 Rear NA NA has SAR below 50% of the limit. 162MHz) Front NA NA The highest MPE configuration 150.8000 0.29 0.20 144.5 Rear NA NA has SAR below 50% of the limit. Front 0.65 0.050 173.0125 0.32 0.20 159.1 Rear 1.03 0.048 HAD4009A, 1/4 Front 0.45 0.035 Roof Wave (162- 165.0125 0.31 0.20 152.9 174MHz) Rear 0.66 0.035 Front NA NA The 2nd highest MPE 162.0000 0.28 0.20 140.2 configuration has SAR below Rear NA NA 75% of the limit 14

FCC ID: AZ492FT7118 Report ID: P8878-EME-00003 Table 4: SAR Simulation Reduction Considerations for Passenger % To Adjusted SAR Mount Freq P.D. FCC Limit FCC Exposure Results (W/kg) Antenna Kit# SAR Simulation Reduction Location (MHz) (mW/cm^2) (mW/cm^2) Spec Location 1g WB Limit Back Center 0.33 0.011 158.0125 0.37 0.20 185.7 Back Side 0.57 0.008 AN000131A01, Back Center NA NA The highest MPE configuration Roof 1/4 wave (136- 165.0125 0.35 0.20 175.2 has SAR below 50% of the 870MHz) Back Side NA NA limit. Back Center NA NA The highest MPE configuration 150.800 0.29 0.20 142.7 has SAR below 50% of the Back Side NA NA limit. Back Center 0.08 0.006 162.0000 0.34 0.20 171.0 Back Side 0.22 0.005 HAD4016A, 1/4 Back Center NA NA The highest MPE configuration Roof Wave (136- 156.4000 0.32 0.20 160.8 has SAR below 50% of the Back Side NA NA limit. 162MHz) Back Center NA NA The highest MPE configuration 150.8000 0.30 0.20 150.8 has SAR below 50% of the Back Side NA NA limit. Back Center 0.07 0.006 165.0125 0.42 0.20 212.1 Back Side 0.19 0.006 HAD4017A, 1/4 Back Center NA NA The highest MPE configuration Roof Wave (146- 158.0125 0.36 0.20 179.0 has SAR below 50% of the 174MHz) Back Side NA NA limit. Back Center NA NA The highest MPE configuration 150.8000 0.22 0.20 107.9 has SAR below 50% of the Back Side NA NA limit. Back Center 0.21 0.009 158.0125 0.33 0.20 164.9 Back Side 0.29 0.006 HAD4021A, 1/4 Back Center NA NA The highest MPE configuration Roof Wave (136- 150.8000 0.32 0.20 158.1 has SAR below 50% of the 174MHz) Back Side NA NA limit. Back Center NA NA The highest MPE configuration 165.0125 0.28 0.20 138.7 has SAR below 50% of the Back Side NA NA limit. HAD4007A, 1/4 Back Center 0.30 0.013 Roof Wave (144- 150.8000 0.37 0.20 184.9 150.8MHz) Back Side 0.54 0.012 Back Center 0.08 0.006 162.0000 0.36 0.20 182.0 Back Side 0.22 0.006 HAD4008A, 1/4 Back Center NA NA The highest MPE configuration Roof Wave (150.8- 156.4000 0.35 0.20 174.8 has SAR below 50% of the 162MHz) Back Side NA NA limit. Back Center NA NA The highest MPE configuration 150.8000 0.25 0.20 125.1 has SAR below 50% of the Back Side NA NA limit. Back Center 0.07 0.006 165.0125 0.35 0.20 173.1 HAD4009A, 1/4 Back Side 0.19 0.006 Roof Wave (162- 174MHz) Back Center NA NA The highest MPE configuration 162.0000 0.29 0.20 143.8 has SAR below 50% of the Back Side NA NA limit. 15

FCC ID: AZ492FT7118 Report ID: P8878-EME-00003 Results of SAR Computations The overall simulated results the worst case peak SAR values were identified and SAR value in corresponding locations of the human body model. The maximum peak 1-g SAR is 1.03 W/kg, less than the 1.6 W/kg limit. The maximum whole-body average SAR for is 0.050 W/kg, less than the 0.08 W/kg limit. Conclusions Under the test conditions described for evaluating passenger exposure to the RF electromagnetic fields emitted by vehicle-mounted antennas used in conjunction with these mobile radio products, the present analysis shows that the computed SAR values are compliant with the US FCC exposure limits for the general public. References [1] IEEE Standard C95.1-1999. IEEE Standard for Safety Levels with Respect to Human Exposure to RF Electromagnetic Fields, 3 kHz to 300 GHz. [2] http://www.nlm.nih.gov/research/visible/visible_human.html [3] Simon,W., Bit-Babik, G., “Effect of the variation in population on the whole-body average 1379 SAR of persons exposed to vehicle mounted antennas W. Simon”, ICEAA September 2-7, 2012, Cape 1380 Town. 16


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