EM7511 Module FCC MPE Evaluation

FCC ID: N7NEM75S

RF Exposure Info

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FCCID_4061241

MPE Evaluation for EM7511
     Radio Module

          October 30, 2018


1. Introduction

     In this application we seek modular approval for the EM7511 radio module for
     use in standalone and collocated simultaneous transmission under mobile and
     fixed configurations. This Maximum Permissive Exposure (MPE) report
     demonstrates compliance analysis for EM7511 radio module with FCC CFR 47
     §2.1091 and IC RSS-102 for standalone and collocated transmission in the
     exposure conditions where a separation distance of at least 20 centimeters is
     normally maintained between the transmitter's radiating structure(s) and the body
     of the user or nearby persons. 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.


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 EM7511 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
                     TX Freq Range                           Ant      Time-                EIRP/ERP Limits
    Operating Mode                      Cond    Avg Cond                          Limit
                         (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        23.8       0.20        9       32.8       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
                                                                                               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        23.8       0.20        9       32.8       34.39          EIRP
                                                                                                23
                                                                                           dBm/10MHz
   LTE Band 48       3550 3700         23        0.20        0        23        34.39          EIRP
                                                                                               3W
   LTE Band 14       788     798       24        0.25        6        30        30.93          ERP
                                                                                               1W
   LTE Band 66       1710 1780         24        0.25        6        30        33.27
                                                                                               EIRP

                     Table 2: EM7511 Stand-Alone Transmission


4. Collocated Transmission

When EM7511 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 WLAN transmitter, a Bluetooth transmitter and a WiGig
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 (EM7511 MPE ratio) + Max (WLAN MPE ratio) + BT MPE Ratio +
                       WiGig MPE
                     = 0.545+0.372+0.015+0.063=0.995 < 1.0

                                                Max     Max             Source-
                                               Time-   Time-   Max       Based     Power
                                                                         Time-                IC MPE       IC
                                                 Avg     Avg    Ant                Density
    Operating Mode       TX Freq Range (MHz)                           Averaged                Limit   PwrDensity
                                                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     4        28        1.26      4.48       0.280
    LTE Band 2
 WCDMA Band IV
                          1710      1755        24     0.25     4        28        1.26      4.24       0.296
    LTE Band 4
 WCDMA Band V
                          824        849        24     0.25     4        28        1.26      2.58       0.487
    LTE Band 5
    LTE Band 7           2500 2570             23.8    0.20     4       27.8       1.00      5.50       0.218
   LTE Band 12            699   716             24     0.25     4        28        1.26      2.30       0.545
   LTE Band 13            777   787             24     0.25     4        28        1.26      2.47       0.507
   LTE Band 26            814   849             24     0.25     4        28        1.26      2.55       0.491
   LTE Band 30           2305 2315              23     0.20     1        24        0.50      5.20       0.096
   LTE Band 41           2496 2690             23.8    0.20     4       27.8       1.00      5.49       0.218
   LTE Band 48           3550 3700              23     0.20     0        23        1.00      6.99       0.057
   LTE Band 14            788   798             24     0.25     4        28        1.26      2.50       0.502
   LTE Band 66           1710 1780              24     0.25     4        28        1.26      4.24       0.296
  WLAN 2.4 GHz           2400 2500                                       30        1.99      5.35       0.372
  WLAN 5 GHz             5150 5850                                       30        1.99      9.01       0.221
        BT               2400 2500                                       16        0.08      5.35       0.015
      WiGig              58320 62640                                     25        0.63      10.00      0.063

                            Table 3: EM7511 Collocated Transmission


5. Conclusion

  The analysis presented in this report concludes that the EM7511 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.

                                                                Max
                                                             Time-Avg   Antenna Gain Limit (dBi)   EIRP Limits
                     Operating Mode    TX Freq Range (MHz)      Cond                                 (dBm)
                                                               Power    Standalone    Collocated
                                                               (dBm)
                   WCDMA Band II
                                       1850        1910        24           6             4           30
                      LTE Band 2
                   WCDMA Band IV
                                       1710        1755        24           6             4           30
                      LTE Band 4
                   WCDMA Band V
                                       824          849        24           6             4           30
                      LTE Band 5
                      LTE Band 7      2500         2570       23.8          9             4          32.8
      EM7511




                     LTE Band 12       699          716        24           6             4           30
                     LTE Band 13       777          787        24           6             4           30
                     LTE Band 26       814          849        24           6             4           30
                     LTE Band 30      2305         2315        23           1             1           32
                     LTE Band 41      2496         2690       23.8          9             4          32.8
                     LTE Band 48      3550         3700        23           0             0           23
                     LTE Band 14       788          798        24           0             0           24
                     LTE Band 66      1710         1780        24           6             4           30
                    WLAN 2.4 GHz      2400         2500                                               30
    Transmitters




                    WLAN 5 GHz        5150         5850                                               30
    Collocated




                          BT          2400         2500                                               16
                        WiGig         58320        62640                                              25


                                 Table 4: EM7511 RF Exposure Conditions



Document Created: 2018-10-30 13:10:02
Document Modified: 2018-10-30 13:10:02

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