RF Exposure

FCC ID: RI7HE9223GR

RF Exposure Info

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FCCID_3230880

AT4wireless, S.A.U Parque Tecnologico de Andalucía, C/ Severo Ochoa 2 29590 Campanillas Málaga, España Subject: RF exposure analysis for the equipment with FCC ID: RI7HE9223GR; IC: 5131A-HE9223GR The device model: HE922-3GR (FCC ID: RI7HE9223GR; IC: 5131A-HE9223GR) is designed to be installed in and used in mobile exposure conditions. The antennas used for this device must be installed to provide a separation distance of at least 20 cm from all the persons and must not be co- located or operating in conjunction with any other antenna or transmitter. MPE exposure limits The table below is excerpted from Table 1B of 47 CFR 1.1310 titled Limits for Maximum Permissible Exposure (MPE), Limits for General Population/Uncontrolled Exposure: Frequency Range (MHz) Power density (mW/cm2) Averaging time (minutes) 300 – 1500 f (MHz) /1500 30 1500 – 100.000 1,0 30 The table below is excerpted from RSS-102, Issue 5, section 4, titled “RF Field Strength Limits for Devices Used by the General Public (Uncontrolled Environment)”: Frequency Range (MHz) Power density (W/m2) Reference Period (minutes) 0.6834 300 – 6000 0.02619ƒ 6 6000 - 15000 10 6 15000 - 150000 10 616000/ ƒ 1.2 Compliance analysis PG Using the equation S to calculate the exposure to electromagnetic fields 4R 2 where: S = power density (in appropriate units, e.g. mW/cm 2) P = power input to the antenna (in appropriate units, e.g., mW) G = power gain of the antenna in the direction of interest relative to an isotropic radiator R = distance to the center of radiation of the antenna (appropriate units, e.g., cm) compliance with FCC and IC MPE and EIRP limits is demonstrated based on the following calculations: 1. Standalone analysis 1.1 RF exposure in 2.4 GHz band: Calculations done using the antenna gain specified for this band. Maximum Reference conducted Evaluation Antenna MPE limit MPE limit Frequency frequency S Worst MPE Ratio Frequency output Duty cicle distance gain in USA in Canada Mode Range (Lowest TX slots (mW/cm^2 case MPE (S/MPE Band power (%) (MHz) freq.) ) limit limit) R (cm) (dBi) (mW/cm2) (mW/cm2) (MHz) Pin (dBm) 2402 - 2,4 ISM BLE 2402,0 5,49 N/A 100,0% 20 2,30 0,0012 1,0000 0,5351 0,5351 0,0022 2480 BL + EDR 2402 - 2,4 ISM 2402,0 6,27 N/A 100,0% 20 2,30 0,0014 1,0000 0,5351 0,5351 0,0027 (GFSK) 2480 BL + EDR 2402 - 2,4 ISM (pi/4- 2402,0 6,90 N/A 100,0% 20 2,30 0,0017 1,0000 0,5351 0,5351 0,0031 2480 DQPSK) BL + EDR 2402 - 2,4 ISM 2402,0 6,82 N/A 100,0% 20 2,30 0,0016 1,0000 0,5351 0,5351 0,0030 (8-DPSK) 2480 WiFi 2.4 2412 - 2,4 ISM GHz 2412,0 19,32 N/A 100,0% 20 2,30 0,0289 1,0000 0,5366 0,5366 0,0539 2462 (802.11b) WiFi 2.4 2412 - 2,4 ISM GHz 2412,0 17,21 N/A 100,0% 20 2,30 0,0178 1,0000 0,5366 0,5366 0,0332 2462 (802.11g) WiFi 2.4 GHz 2412 - 2,4 ISM 2412,0 16,42 N/A 100,0% 20 2,30 0,0148 1,0000 0,5366 0,5366 0,0276 (802.11n20 2462 ))

1.2 Maximum antenna gains for GSM and UMTS interfaces. Calculations done to comply with MPE and EIRP limits Now we calculate the maximum antenna gains so compliance with MPE and EIRP in both USA and Canada is fulfilled. Maximu m EIRP EIRP Antenna Maximum limit in limit in gain Referenc Antenn Antenn Antenn Antenn conducte USA Canad to e a gain a gain a gain a gain d Evaluatio MPE limit MPE limit per a comply Frequenc frequenc Duty to meet to meet to meet to meet output TX n in USA in Canada FCC per MPE Frequenc y Range y cicle FCC FCC ISED ISED Mode power slot distance §22,91 SRSP- and y Band (Lowest MPE EIRP MPE EIRP (per tune- s (mW/cm^ (mW/cm^ 3, 503, EIRP (MHz) freq.) (%) limit limit limit limit up) (cm) 2) 2) §24,23 SRSP- in all 2 510 bands in (MHz) G (dBi) G (dBi) G (dBi) G (dBi) (dBm) USA and (W) (W) Canada (dBi) GSM/GPR 824,2 - 11,480 11,500 GSM 850 S (class 824,2 32,50 2 25,0% 20 0,5495 0,2576 7,93 8,09 4,64 8,10 848,8 0 0 10) 4,64 WCDMA / 826,4 - 100,0 11,480 11,500 UMTS B5 826,4 23,50 N/A 20 0,5509 0,2581 10,92 17,09 7,63 17,10 HSUPA 846,6 % 0 0 GSM/GPR 1850,2 - PCS 1900 S (class 1850,2 30,90 2 25,0% 20 1,0000 0,4477 2,0000 2,0000 12,13 2,11 8,64 2,11 1909,8 10) 2,11 WCDMA / 1852,4 - 100,0 UMTS B2 1852,4 23,40 N/A 20 1,0000 0,4480 2,0000 2,0000 13,61 9,61 10,12 9,61 HSUPA 1907,6 % 2. Co-location analysis 2.1 Co-location with other transmitter in mobile exposure conditions As specified in the operational description, cellular transmitter can work simultaneously with the transmitter in the 2.4GHz band so an analysis of the co-location with other transmitter in mobile exposure conditions is required. Only one of these 2.4 GHz modes works at a given moment and it can work simultaneously with any of the cellular modes. According to KDB 447498 D01 General RF Exposure Guidance v06, 7.2: Simultaneous transmission MPE test exclusion applies when the sum of the MPE ratios for all simultaneous transmitting antennas incorporated in a host device, based on calculated or measured field strengths or power density, is ≤ 1.0. As the maximum calculated MPE ratio for the device is 0.0539 in the mode WiFi 2.4 GHz (802.11n20), the product can be co-located with other antennas in the cellular mode providing that the sum of the MPE ratios for all the other simultaneous transmitting antennas incorporated in a host device, based on calculated or measured field strengths or power density is ≤ 1.0 – 0.0539 = 0.9461 2.2 RF exposure for GSM and UMTS modes The antenna gains calculated in 1.2 are in compliance with 2 criteria, MPE and EIRP limits for both countries, USA and Canada. Nevertheless there is a third criterion that we need to meet. As the cellular interface can work simultaneously with the 2.4 GHz interface, the MPE ratio for each cellular mode must also be in compliance with the MPE Ratio for use in co-location defined in 2.1 The antenna gain of 2.11 dBi for the 1900 MHz band is not a problem. If we would use an antenna gain of 4.64 dBi in the 850 MHz band, then the MPE Ratio for the GSM/GPRS (class 10) mode would be greater than 0.9461 Hence, to comply with this third criterion of MPE ratio to work in co-location below 0.9461, the antenna gain has to be reduced until 4.37 dBi The table below shows the values of S and the MPE ratio under these conditions Maximum Antenna Maximum gain Reference conducted to comply MPE limit MPE limit Frequency frequency output Evaluation MPE and S MPE Ratio Duty cicle in USA in Canada Frequency Range (Lowest power distance EIRP Worst Mode TX slots Band freq.) (per tune- in all (mW/cm^2 case MPE (S/MPE (%) (mW/cm^2 (mW/cm^2 (MHz) up) (cm) bands in ) limit) ) ) (MHz) USA and Pin (dBm) Canada (dBi) GSM/GPR 824,2 - GSM 850 S (class 824,2 32,50 2 25,0% 20 4,37 0,2423 0,5495 0,2576 0,2576 0,9407 848,8 10) WCDMA / 826,4 - UMTS B5 826,4 23,50 N/A 100,0% 20 4,37 0,1220 0,5509 0,2581 0,2581 0,4729 HSUPA 846,6 GSM/GPR 1850,2 - PCS 1900 S (class 1850,2 30,90 2 25,0% 20 2,11 0,0995 1,0000 0,4477 0,4477 0,2222 1909,8 10) WCDMA / 1852,4 - UMTS B2 1852,4 23,40 N/A 100,0% 20 2,11 0,0708 1,0000 0,4480 0,4480 0,1579 HSUPA 1907,6

3 Conclusion To meet all the established criteria, the antenna gains in the cellular modes must be: Frequency range Antenna gain 850 MHz band 4.37 dBi 1900 MHz band 2.11 dBi 2.4 GHz band 2.3 dBi Final MPE with Co-location. The worst cases of working in co-location are below. They are WiFi 2.4 GHz (802.11b) and GSM/GPRS (class 10) The antenna gain used for the 850 MHz band is the optimum case to comply with the MPE and EIRP limits and additionally give an MPE ratio below 0.9461 as calculated in 2.2 Maximum conducted Reference output Evaluation Antenna MPE limit MPE limit Frequency frequency S Worst MPE Ratio Frequency power Duty cicle distance gain in USA in Canada Mode Range (Lowest TX slots (mW/cm^2 case MPE (S/MPE Band (per tune- (%) (MHz) freq.) ) limit limit) up) R (cm) (dBi) (mW/cm2) (mW/cm2) (MHz) Pin (dBm) WiFi 2.4 2412 - 2,4 ISM GHz 2412,0 19,32 N/A 100,0% 20 2,30 0,0289 1,0000 0,5366 0,5366 0,0539 2462 (802.11b) GSM/GPR 824,2 - GSM 850 S (class 824,2 32,50 2 25,0% 20 4.37 0,2423 0,5495 0,2576 0,2576 0,9407 848,8 10) The sum of MPE ratios in this case is 0.0539 + 0.9407 = 0.9946 The sum of S for both modes is 0.0289 + 0.2423 = 0.2713 (mW/cm^2)  S = 2.713 W/m^2 In compliance with all limits of MPE, EIRP and MPE for working in co-location PA By: Brian Tucker Title: Senior Vice President of Quality Company: Telit Wireless Solutions, Inc.


Document Created: 2016-12-15 16:35:37
Document Modified: 2016-12-15 16:35:37
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