EM7455 Module FCC MPE Evaluation

FCC ID: N7NEM7455

RF Exposure Info

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FCCID_2693960

MPE Evaluation for EM7455 Radio Module July 8, 2015

1. Introduction In this application we seek modular approval for the EM7455 radio module for use in standalone and collocated simultaneous transmission under mobile configuration. This Maximum Permissive Exposure (MPE) report demonstrates compliance analysis for EM7455 radio module with FCC CFR 47 §2.1091 and IC RSS-102 for standalone and collocated transmission in mobile exposure conditions. The MPE analysis is limited for US / Canada bands only. The general population/uncontrolled exposure limits are applicable to situations in which the general public may be exposed or in which persons who are exposed as a consequence of their employment may not be made fully aware of the potential for exposure or cannot exercise control over their exposure. Any collocated transmitter must have a valid FCC ID documenting equivalent or degraded RF characteristics with the collocated parameters defined in this MPE report. A separation distance of 20cm or more shall be maintained between the end user and each WWAN, WiMAX or WLAN, and Bluetooth transmitting antenna. Portable user conditions or additional collocated transmitters not allowed based on this RF exposure analysis require a Class II permissive change and updated RF exposure report.

2. RF Exposure Limits and Equations FCC Limits: According to FCC OET Bulletin 65 Supplement C, the criteria listed in Table 1 shall be used to evaluate the environmental impact of human exposure to radio frequency (RF) radiation as specified in §1.1307. Table 1 : Limits for Maximum Permissible Exposure (MPE) IC Limits: IC has adopted the RF field strength limits established in Health Canada’s RF exposure guideline. The limits are shown in Table 2 below per RSS- 102. Table 2 : RF Field Strength Limits for Devices Used by the General Public (Uncontrolled Environment)

In the frequency range of 300-6000 MHz, the IC limits are more stringent than the FCC limits. The MPE evaluation in this report will be based on the IC limits, so the deduced output power and antenna gain limits will guarantee compliance with both FCC and IC requirements. EQUATIONS: EIRP (dBm) = Conducted Power (dBm) + Antenna Gain (dBi) Power density is given by : S = EIRP / (4 π * D^2) where S = Power density (mW/cm^2) EIRP = Equivalent Isotropic Radiated Power (mW) D = Separation distance (cm)

3. Stand-Alone Transmission When EM7455 module transmits as a stand-alone mobile device, the source- based time-averaged EIRP is calculated by summing up conducted power and antenna gain. A 100% duty cycle is used for calculations to present a worse-case analysis. The antenna gains are chosen so that the resulted radiated power levels are within the limits specified by the FCC rules and IC Radio Standards Specifications (RSS). The IC exemption limits for routine RF exposure evaluation are calculated using the lowest frequency of the operating band presenting the most stringent limits. As shown in Table 2 below, the resulted EIRP are always below the IC exemption limits for all the operating modes. Source- Max IC Max Based Time-Avg Max Time- Exemption EIRP/ERP TX Freq Range Ant Time- Operating Mode Cond Avg Cond Limit Limits (MHz) Gain Averaged Power Power (W) (EIRP) (dBi) Max EIRP (dBm) (dBm) (dBm) WCDMA Band II 2W 1850 1910 24 0.25 6 30 33.50 LTE Band 2 EIRP WCDMA Band IV 1W 1710 1755 24 0.25 6 30 33.27 LTE Band 4 EIRP WCDMA Band V 6.3 W 824 849 24 0.25 6 30 31.10 LTE Band 5 ERP 2W LTE Band 7 2500 2570 23 0.20 9 32 34.39 EIRP 3W LTE Band 12 699 716 24 0.25 6 30 30.61 ERP 3W LTE Band 13 777 787 24 0.25 6 30 30.93 ERP 2W LTE Band 25 1850 1915 24 0.25 6 30 33.50 EIRP 7W LTE Band 26 814 849 24 0.25 6 30 31.06 ERP 0.25 W LTE Band 30 2305 2315 23 0.20 1 24 34.15 EIRP 2W LTE Band 41 2496 2690 23 0.20 9 32 34.39 EIRP Table 2: EM7455 Stand-Alone Transmission

4. Collocated Transmission When EM7455 module co-transmits with radio transmitter(s) as a mobile device, per KDB 447498 D01, 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 the calculated/estimated, numerically modeled or measured field strengths or power density, is ≤ 1.0. The evaluation here considers a WiMAX or WLAN transmitter, and a Bluetooth transmitter as collocated transmitters. Their radiated output power levels are listed in Table 3 below. The MPE ratio is defined by the ratio of power density to MPE limit. The sum of the MPE ratios is calculated as follows: ∑𝑀𝑃𝐸 𝑅𝑎𝑡𝑖𝑜 = Max (EM7455 MPE ratio) + Max (WLAN/WiMax MPE ratio) + BT MPE Ratio = 0.864+0.121+0.012=0.997 < 1.0 Max Max Source- Time- Time- Max Based Power Time- IC MPE IC TX Freq Range Avg Avg Ant Density Operating Mode Averaged Limit PwrDensity (MHz) Cond Cond Gain @20 cm Max EIRP (W/m2) MPE Ratio Power Power (dBi) (W/m^2) (dBm) (W) WCDMA Band II 1850 1910 24 0.25 6 30 1.99 4.48 0.444 LTE Band 2 WCDMA Band IV 1710 1755 24 0.25 6 30 1.99 4.24 0.469 LTE Band 4 WCDMA Band V 824 849 24 0.25 6 30 1.99 2.58 0.772 LTE Band 5 LTE Band 7 2500 2570 23 0.20 9 32 3.15 5.50 0.573 LTE Band 12 699 716 24 0.25 6 30 1.99 2.30 0.864 LTE Band 13 777 787 24 0.25 6 30 1.99 2.47 0.804 LTE Band 25 1850 1915 24 0.25 6 30 1.99 4.48 0.444 LTE Band 26 814 849 24 0.25 6 30 1.99 2.55 0.779 LTE Band 30 2305 2315 23 0.20 1 32 0.50 5.20 0.096 LTE Band 41 2496 2690 23 0.20 9 32 3.15 5.49 0.574 WLAN 2.4 GHz 2400 2500 25 0.63 5.35 0.118 WLAN 5 GHz 5150 5850 27 1.00 9.01 0.111 2300 2400 25 0.63 5.19 0.121 WiMAX 2500 2700 25 0.63 5.50 0.114 3300 3800 25 0.63 6.65 0.095 BT 2400 2500 15 0.06 5.35 0.012 Table 3: EM7455 Collocated Transmission

5. Conclusion The analysis presented in this report concludes that the EM7455 radio module, when transmitting either in standalone or simultaneously with other co-located radio transmitters within a host device, is compliant with the FCC/IC RF exposure requirements in mobile exposure condition, provided the conducted power and antenna gain do not exceed the limits in Table 4 for each given frequency band and operating mode. Antenna Max Time- EIRP Limits TX Freq Range Gain Operating Mode Avg Cond (dBm) (MHz) Limits Power (dBm) (dBi) WCDMA Band II 1850 1910 24 6 30 LTE Band 2 WCDMA Band IV 1710 1755 24 6 30 LTE Band 4 WCDMA Band V 824 849 24 6 30 LTE Band 5 EM7455 LTE Band 7 2500 2570 23 9 32 LTE Band 12 699 716 24 6 30 LTE Band 13 777 787 24 6 30 LTE Band 25 1850 1915 24 6 30 LTE Band 26 814 849 24 6 30 LTE Band 30 2305 2315 23 1 32 LTE Band 41 2496 2690 23 9 32 WLAN 2.4 GHz 2400 2500 25 Collocated Radio Transmitters WLAN 5 GHz 5150 5850 27 2300 2400 25 WiMAX 2500 2700 25 3300 3800 25 BT 2400 2500 15 Table 4: EM7455 RF Exposure Conditions


Document Created: 2015-07-08 11:13:35
Document Modified: 2015-07-08 11:13:35
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