Test Report PD Simulation

FCC ID: MSQZ01QD

Test Report

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FCCID_4124655

Revision history

Revision Date Description
A November 2018 Initial release

80-YB869-3 Rev. A MAY CONTAIN U.S. AND INTERNATIONAL EXPORT CONTROLLED INFORMATION 2

Contents

1 Scope ..................................................................................................................................... 5

2 Product Description .............................................................................................................. 6
2.1 802.11ad antenna modules .......................................................................................................................6
2.2 802.11ad antenna configurations ...............................................................................................................7

3 Worst-Case Determination Using the Simulation ............................................................... 8
3.1 Modeling ....................................................................................................................................................8
3.2 Setup .........................................................................................................................................................9
3.2.1 Platform .................................................................................................................................... 9
3.2.2 Channels .................................................................................................................................. 9
3.2.3 Error computation and convergence......................................................................................... 9
3.2.4 Absorbing boundary condition ................................................................................................ 11
3.3 EIRP comparison measured vs. simulation ............................................................................................. 12
3.4 Simulation power density results ............................................................................................................. 12

4 Power Density Measurement ..............................................................................................14

5 Conclusion ...........................................................................................................................15

A Uncertainty Budget .............................................................................................................16
A.1 Simulation uncertainty budget ................................................................................................................. 16

B Simulated Power Density Distributions .............................................................................17

C 802.11ad Antenna Modules Images, Drawings, and Charts .............................................82
C.1 802.11ad antenna module images inside ASUS_Z01QD........................................................................ 82
C.2 Antenna module array elements drawing ................................................................................................ 83
C.3 Simulation modeling drawings ................................................................................................................. 83

Figures

Figure 3-1 Simulation mesh setup used in ASUS 802.11ad antenna module – Top module ....................................... 10
Figure 3-2 Simulation mesh setup used in ASUS 802.11ad antenna module – Bottom module .................................. 11
Figure 3-3 Simulated peak power density in 1 cm2-averaged area – Top antenna ...................................................... 13
Figure 3-4 Simulated peak power density in 1 cm2-averaged area – Bottom antenna ................................................. 13
Figure C-1 802.11ad antenna module inside ASUS_Z01QD ....................................................................................... 82
Figure C-2 Relative position and orientation of top and bottom antenna modules ....................................................... 82
Figure C-3 Antenna module array elements view ........................................................................................................ 83
Figure C-4 Orientation of the simulated power distribution relative to the ASUS_Z01QD device ................................ 83
Figure C-5 Top module ................................................................................................................................................ 84
Figure C-6 Bottom module ........................................................................................................................................... 84

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ASUS Z01QD Smartphone 802.11ad FCC RF Exposure Simulation Contents

Figure C-7 Simulation model structure – Top module .................................................................................................. 85
Figure C-8 Simulation model structure – Bottom module ............................................................................................. 85

Tables

Table 3-1 Measured and Simulated EIRP .................................................................................................................... 12
Table 5-1 Highest simulated power density summary used to define power density measurements ........................... 15
Table A-1 Standard uncertainty budget for simulated values of power density ............................................................ 16

80-YB869-3 Rev. A MAY CONTAIN U.S. AND INTERNATIONAL EXPORT CONTROLLED INFORMATION 4

1 Scope

The purpose of this report is to identify test configurations for measurement of the 60 GHz
802.11ad radios embedded in the ASUS phone model ASUS_Z01QD for the FCC RF exposure
simulation.
Two 802.11ad modules were integrated into the ASUS_Z01QD smartphone platform.
■ Each 11ad radio consists of two separate modules (see Section 2.1).
■ Appendix C 802.11ad Antenna Modules Images, Drawings, and Charts shows the placement
of the two 802.11ad antenna modules.
■ The closest distance between the 802.11ad antenna module and the body or hands of an end
user will be in the near field for the 60 GHz frequency.
Final compliance is evaluated through measurements in a third-party test report.
The RF exposure assessment and simultaneous transmission with other radios supported in the
phone are evaluated in a separate ASUS test report.

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2 Product Description

ASUS_Z01QD is a smartphone radio integrating the following technologies:
■ GSM bands 2/3/5/8
■ WCDMA bands 1/2/3/4/5/6/8/19
■ FDD-LTE bands 1/2/3/4/5/7/8/12/17/18/19/20/26/28/29/30/32
■ TDD-LTE bands 34/38/39/40/41(full 41) + LAA
■ 802.11a/b/g/n/ac
■ Bluetooth
■ 802.11ad 60 GHz

2.1 802.11ad antenna modules
The ASUS_Z01QD smartphone integrates two 802.11ad antenna modules operating in the 60
GHz band.
The 11ad antenna modules are connected to a baseboard which receives signals from the
baseband unit.
■ Each 11ad radio consists of two separate modules:
□ 802.11ad antenna module
● 60 GHz RF and antenna array elements on a printed circuit board
● Module interfaces to a baseband unit
□ Baseband unit
● Provides power, control signals, and IF required for the 802.11ad antenna module
■ One 11ad module is located at the top and the second module is at the bottom of the phone.
□ The 802.11ad antenna module inside ASUS_Z01QD, and the relative position and
orientation of top and bottom antenna modules.
● For a closer view of the position and orientation of the 11ad antenna module relative
to ASUS_Z01QD and the top (Side A) and bottom (Side B) drawings of the 802.11ad
antenna module, see Appendix C.
■ Device firmware selects which 11ad antenna is used for transmission when only one antenna
module can transmit at any one time.
■ These 802.11ad modules (including the antenna modules and baseband unit) support all
mandatory channels in IEEE 802.11ad (i.e., Channels 1, 2, and 3) and comply with the IEEE
802.11ad standard.

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ASUS Z01QD Smartphone 802.11ad FCC RF Exposure Simulation Product Description

2.2 802.11ad antenna configurations
An antenna configuration or sector is a given combination of amplitude and phase of array
elements (see Figure C-3).
■ There are 32 antenna configurations available for each channel to steer the antenna beam and
establish a good communication link with the best signal to noise ratio.
■ This results in a total 96 antenna configurations available per 11ad array module to handle
surrounding transmission environments.
■ Only one antenna configuration is active at any time.

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3 Worst-Case Determination Using the
Simulation

Depending on the transmission environment, the 802.11ad antenna modules installed inside
ASUS_Z01QD can activate an optimal antenna configuration to establish a good communication
link.
NOTE: Simulation modeling drawings are based on the array model provided by Murata and the 3D
platform provided by ASUS (see Appendix A.3).
Ansys Electromagnetics suite 18.0.0 simulation software evaluated all possible antenna
configurations to save time.
■ The simulation module includes the 802.11ad antenna module and all components
surrounded within 5λ.
■ The simulation goal is to perform a relative comparison and determine the worst-case antenna
configurations having the highest peak 1 cm2-averaged power density for each channel, and
then perform a power density measurement to demonstrate compliance on the worst cases
identified.
□ It is difficult to accurately simulate power density levels to an absolute-level due to the
lack of accurate material properties for non-metal components at 60 GHz.
□ Final measurement assessment using a larger averaging area will result in lower reported
power density.
□ Based on the placement of the 802.11ad antenna modules, the power density was
simulated on four evaluation planes to determine the worst case antenna configurations:
front, back, bottom, and side (see Figure C-4).
■ The separation distance between the evaluation plane and the corresponding surface of
ASUS_Z01QD is 0.5 mm.

3.1 Modeling
Complete models of the top and bottom of the 802.11ad antenna modules are from the antenna
manufacturer Murata, respectively (see Appendix A.3).
The entire mechanical structure within 5λ surrounding the antenna module are also included in
the simulation.
■ The 3D platform of the device was provided by ASUS.
■ With the exception of adhesive materials used in the phone, all components within a 35 mm
radius of 11ad antennas modules are part of the simulation model.
■ All other antennas in the device were also included in the simulation.

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ASUS Z01QD Smartphone 802.11ad FCC RF Exposure Simulation Worst-Case Determination Using the Simulation

3.2 Setup
Finite element analysis (FEM) simulations were performed to assess the power density of the
802.11ad antenna module (see Appendix C).
A layered breakdown of the mechanical structure included in the top and bottom modules of the
simulation model:
■ Full model: Entire assembly.
■ Without screen: LCD screen removed (shields, battery, FPCs, screws, LCD mirror and metal
frames) and were modeled as aluminum
■ Only plastic components: All metal parts removed, all non-conductive components were
modeled as lossless Sabic material with a relative permittivity of 2.92
The worst-case exposure is expected from the back of ASUS_Z01QD because exposure from
other directions will be significantly reduced by the surrounding metal components (see top
(Side A) Figure C-1).

3.2.1 Platform
The simulation includes the edge of the platform:
■ The platform was cut at 18.5 mm away from the top module edge to reduce simulation time.
□ The overall cut from the top of the platform is 31.5 mm, which is more than five
wavelengths.
■ The platform was cut at 19.5 mm away from the bottom module edge to reduce simulation
time.
□ The overall cut of the platform is 41 mm which is more than five wavelengths.
■ The modules are mostly shielded by metallic structures in the –y direction.
□ All components in the vicinity of the module were simulated by assuming they were
mostly made of metal.

3.2.2 Channels
ASUS_Z01QD supports 801.11ad Channels 1 to 3. Simulations were performed at the center
frequencies of each channel:
■ Channel 1: 58.5 GHz
■ Channel 2: 60.5 GHz
■ Channel 3: 62.5 GHz

3.2.3 Error computation and convergence
In the simulation setup, auto initial mesh was:
■ Selected.
■ Defined “lambda refinement” (Ansys Electromagnetics Suite 18.0.0 refines the initial mesh
based on the material-dependent wavelength).

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ASUS Z01QD Smartphone 802.11ad FCC RF Exposure Simulation Worst-Case Determination Using the Simulation

■ Influence was less than 0.05 dB, which confirms that the space between module and
computational boundary is sufficient.
■ This influence on power density was also included in the simulation uncertainty budget.
For the complete estimated total simulation uncertainty, see Appendix A.

3.3 EIRP comparison measured vs. simulation
Measured EIRP was compared to simulated EIRP to verify accuracy of the simulation model for
selected test configurations in Table 3-1.
■ As expected, due to unknowns in the device materials, the measured EIRP was less than the
simulated EIRP.
■ The variance was not fully investigated with the expectation that measured power density
results will have greater than 3dB of margin.

Table 3-1 Measured and Simulated EIRP
Antenna
Exposure
Module Channel Sector Simulated Measured Delta
Plane
EIRP (dBm) EIRP (dBm) (dB)
Bottom Rear 2 6 7.6 4.9 2.7
Bottom Rear 3 25 9.5 5.15 4.3
Bottom Rear 1 16 8.7 6.62 2.1
Top Front 3 3 10.3 6.11 4.2

3.4 Simulation power density results
A total of 96 antenna configurations (32 configurations per channel) were evaluated at each
evaluation plane for each antenna module (see Figure C-3).
■ This represents a total of 960 configurations evaluated to determine the worst-case power
density configurations (32 array configurations x 3 channels x 5 device surfaces x 3 arrays).
■ The surface furthest from the 11ad array on the top or bottom of the device was not included.
■ The objective of the simulation was to compare the power density levels among antenna
configurations for all evaluation planes to determine the worst-case antenna configuration for
each channel.
■ Then, power density is measured for the identified worst-case antenna configurations to
demonstrate compliance. For measurement setup and test results, see Chapter 4.
For each channel, the simulated peak 1 cm2 averaged power density for all antenna configurations
at each evaluation plane (see Figure 3-3 and Figure 3-4.
The highest 1 cm2-averaged power density antenna configurations identified for measurement are
noted with red circles. These power densities are total power densities (PDtotal) where
PDtotal =�𝑃𝑃𝑃𝑃𝑥𝑥 + 𝑃𝑃𝑃𝑃𝑦𝑦 + 𝑃𝑃𝑃𝑃𝑧𝑧

NOTE: The horizontal axis is the antenna configuration number. Gaps in numbering are due to unused
and unlisted antenna configurations.

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4 Power Density Measurement

Power density measurements are not assessed in this test report.

NOTE: See SPORTON Report No FA852405-06 for measured test results.

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5 Conclusion

The worst-case antenna configurations having the highest 1 cm2-averaged power density for each
channel and 11ad module, and the 4 cm2 results for comparison in the measurement report are
identified in Table 5-1.
Simulation results are provided for both the top and bottom 11ad antenna arrays on the front, rear,
top, and bottom device surfaces near the antenna array.
Measured test results are expected to be lower than the simulated results and will be used to show
compliance for the device.

Table 5-1 Highest simulated power density summary used to define power density
measurements
Simulated Pd Simulated Pd
Antenna Exposure (1cm2) ) with (4cm2) with
Channel Sector
Module Plane 80% duty 80% duty
cycle cycle
Bottom Rear 2 6 11.21 5.81
Bottom Rear 1 2 11.19 6.43
Bottom Rear 3 25 11.17 5.55
Bottom Rear 1 16 11.16 5.62
Bottom Side 2 29 6.33 2.35
Bottom Front 2 31 4.85 1.90
Top Front 1 18 11.21 4.41
Top Front 3 3 11.21 4.56
Top Front 3 13 11.20 4.82
Top Front 1 31 11.16 5.52
Top Left 2 21 5.31 1.59
Top Top 3 13 4.22 1.67
Top Back 2 19 6.77 3.27
Top Front 1 18 11.21 4.41

For complete simulation results of point power density distributions on the back plane (bottom
module) and front plane (upper module) for all antenna configurations, see Appendix B.

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A Uncertainty Budget

A.1 Simulation uncertainty budget
Table A-1 contains the measurement uncertainty analysis for the simulation.

Table A-1 Standard uncertainty budget for simulated values of power density
Uncertainty Std. unc Std. unc
# Description Prob. dist. Div.
(± %) (± %) (± dB)
1 FEM mesh density 0.10% Norm 1 0.10% 0.00
2 Boundary condition 0.80% Norm 1 0.80% 0.03
3 Convergence 0.50% Norm 1 0.50% 0.02
Combined standard uncertainty 0.9% 0.04

Expanded standard uncertainty 1.9% 0.08
1 Mesh density on the exposure plane was changed by limiting the "max length" of mesh size
from auto setting (9.6 mm) to 2 mm.
2 Simulation domain (volume) was decreased by 30% to check the influence of reflections from

boundary conditions on power density.
3 5% versus 3% convergence criteria were compared in Ansys Electromagnetics Suite 18.0.0.

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Document Created: 2018-12-31 13:56:08
Document Modified: 2018-12-31 13:56:08

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