WP8548 Module FCC IC MPE Evaluation_R1

FCC ID: N7NWP8

RF Exposure Info

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FCCID_2915859

MPE Evaluation for WP8548 Radio Module February 15, 2016

1. Introduction In this application we seek modular approval for the WP8548 radio module. This Maximum Permissive Exposure (MPE) report demonstrates compliance analysis for WP8548 radio module with FCC CFR 47 §2.1091 and IC RSS-102 for operation 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 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 collocated transmitting antenna.

2. RF Exposure Limits and Equations FCC Limits: Table 1 lists the MPE limits for general population 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. WP8548 Product Specifications WP8548 will transmit on only one band and mode of operation at any one time. Table 3 lists the supported frequency bands in Canada/USA and the maximum power in each of those bands. UL Freq. DL Freq. Technology Band Max Power (MHz) (MHz) WCDMA / B2 1850 – 1910 1930 – 1990 24 dBm HSDPA/ HSUPA / B5 824 – 849 869 – 894 24 dBm HSPA+ G850 824 – 849 869 – 894 33 dBm GSM G1900 1850 – 1910 1930 – 1990 30 dBm G850 824 – 849 869 – 894 27.5 dBm EDGE G1900 1850 – 1910 1930 – 1990 26.5 dBm Table 3: WP8548 Frequency Bands and Output Power WP8548 supports multislot Class 10 GPRS and Class 12 EGPRS with power backoff for GMSK modulation at 3 and 4 times slots, as specified in Table 4. Power Backoff (dB) Power Class Mode Band Coding Scheme Modulation Time Slot1 Time Slot2 Time Slot3 Time Slot4 GSM850 MCS1 - MCS4 GSMSK 0 0 3 5 GSM900 GSM850 MCS5 - MCS9 8PSK 0 0 0 0 GSM900 12 EGPRS GSM1800 MCS1 - MCS4 GSMSK 0 0 2 3 GSM1900 GSM1800 MCS5 - MCS9 8PSK 0 0 0 0 GSM1900 Table 4: WP8548 Power Backoff 4. Stand-alone Transmission When WP8548 module transmits as a stand-alone mobile device, the source-based time-averaged EIRP is calculated by summing up conducted power and antenna gain. 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 5 below, the resulted EIRP are always below the IC exemption limits for all the operating modes.

Source- Max Max Based Time- Time- Max IC Time- TX Freq Range Avg Avg Ant Duty Exemption ERP/EIRP Operating Mode Averaged (MHz) Cond Cond Gain Cycle Limit Limits Max Power Power (dBi) (EIRP) EIRP (dBm) (W) G850-GMSK 824 849 33 2.00 4 25% 30.98 31.10 7W ERP (2TS) G850-GMSK 824 849 30 1.00 4 38% 29.74 31.10 7W ERP (3TS) G850-GMSK 824 849 28 0.63 4 50% 28.99 31.10 7W ERP (4TS) G850-8PSK (4TS) 824 849 27.5 0.56 4 50% 28.49 31.10 7W ERP G1900-GMSK 1850 1910 30 1.00 3 25% 26.98 33.50 2W EIRP (2TS) G1900-GMSK 1850 1910 28 0.63 3 38% 26.74 33.50 2W EIRP (3TS) G1900-GMSK 1850 1910 27 0.50 3 50% 26.99 33.50 2W EIRP (4TS) G1900-8PSK (4TS) 1850 1910 26.5 0.50 3 50% 26.49 33.50 2W EIRP WCDMA Band II 1850 1910 24 0.25 3 100% 27.00 33.50 2W EIRP LTE Band 2 WCDMA Band V 824 849 24 0.25 4 100% 28.00 31.10 7W ERP LTE Band 5 Table 5: WP8548 Stand-Alone Transmission 5. Collocated Transmission When WP8548 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 6 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 (WP8548 MPE ratio) + Max (WLAN/WiMax MPE ratio) + BT MPE Ratio = 0.769+0.192+0.037=0.998 < 1.0 Source- Max Max Based Time- Max Power IC Time-Avg Time- IC Power TX Freq Range Avg Ant Duty Density MPE Operating Mode Cond Averaged Density (MHz) Cond Gain Cycle @20 cm Limit Power Max MPE Ratio Power (dBi) (W/m^2) (W/m2) (W) EIRP (dBm) G850-GMSK 824 849 33 2.00 3 25% 29.98 1.98 2.58 0.769 (2TS) G850-GMSK 824 849 30 1.00 3 38% 28.74 1.49 2.58 0.578 (3TS) G850-GMSK 824 849 28 0.63 3 50% 27.99 1.25 2.58 0.486 (4TS) G850-8PSK 824 849 27.5 0.56 3 50% 27.49 1.12 2.58 0.433 (4TS) G1900- 1850 1910 30 1.00 3 25% 26.98 0.99 4.48 0.222 GMSK (2TS) G1900- 1850 1910 28 0.63 3 38% 26.74 0.94 4.48 0.210 GMSK (3TS) G1900- 1850 1910 27 0.50 3 50% 26.99 0.99 4.48 0.222 GMSK (4TS) G1900-8PSK 1850 1910 26.5 0.45 3 50% 26.49 0.89 4.48 0.198 (4TS) WCDMA 1850 1910 24 0.25 3 100% 27.00 1.00 4.48 0.223 Band II WCDMA 824 849 24 0.25 3 100% 27.00 1.00 2.58 0.387 Band V WLAN 2.4 2400 2500 100% 27.00 1.00 5.35 0.186 GHz WLAN 5 5150 5850 100% 27.00 1.00 9.01 0.111 GHz 2300 2400 100% 27.00 1.00 5.19 0.192 WiMAX 2500 2700 100% 27.00 1.00 5.50 0.181 3300 3800 100% 27.00 1.00 6.65 0.150 Bluetooth 2400 2500 100% 20.00 0.20 5.35 0.037 Table 6: WP8548 Collocated Transmission

6. Conclusion The analysis presented in this report concludes that the WP8548 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 7 for each given frequency band and operating mode. Antenna Gain Limits EIRP Limits of TX Freq Range (dBi) Collocated Radio Operating Mode (MHz) Stand- Transmitters Collocated (dBm) Alone GPRS/EDGE850 824 849 4 3 WP8548 GPRS/EDGE1900 1850 1910 3 3 WCDMA Band V 824 849 4 3 WCDMA Band II 1850 1910 3 3 WLAN 2.4 GHz 2400 2500 27 Collocated Radio Transmitters WLAN 5 GHz 5150 5850 27 2300 2400 27 WiMAX 2500 2700 27 3300 3800 27 Bluetooth 2400 2500 20 Table 7: WP8548 RF Exposure Conditions


Document Created: 2016-02-15 17:36:50
Document Modified: 2016-02-15 17:36:50
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