SAR report 2GHz

FCC ID: QDS-BRCM1017

RF Exposure Info

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                                         SAR Test Report
                                  No. SAR_936_2005_FCC_2450MPAGH


                                                                       for the
                                                    Broadcom Corporation

                                         Broadcom 802.11ag Mini PCI Card

                                        Model Number: BCM94318MPAGH

                                                   FCC ID: QDS-BRCM1017



                                            Date of Report:                       7/11/2005
                                            Date of issue:                        7/11/2005
                                            Report Copy No.:                      01




                                                                                                                                       FCC listed # 101450
                                                        Bluetooth Qualification                                                        IC recognized # 3925
                                                             Test Facility
                                                               (BQTF)
          TTI-P-G 081/94-A0

       ACCREDITED ACCORDING TO
              ISO/IEC 17025


                                                                 CETECOM Inc.
                                            411 Dixon Landing Road Š Milpitas, CA 95035 Š U.S.A.
                 Phone: + 1 (408) 586 6200 Š Fax: + 1 (408) 586 6299 Š E-mail: info@cetecomusa.com Š http://www.cetecom.com
                                    CETECOM Inc. is a Delaware Corporation with Corporation number: 2113686
                                     Board of Directors: Dr. Harald Ansorge, Dr. Klaus Matkey, Hans Peter May


V.2.16M-2002-03-12 \\stupendousman\rootappsdata\emc\projects_emc\broadcom\963_2005_heavenly_laptop\bcm94318mpagh\report\2.4   © Copyright by CETECOM
                   ghz\sar_963_2005_fcc_2450_mpagh.doc


SAR Test Report No.
SAR_936_2005_FCC_2450MPAGH
Date of Report: 7/11/2005                                                                  Page 2 of 23

Contents


1. ASSESSMENT ...................................................................................................................4


2. ADMINISTRATIVE DATA...................................................................................................5

     2.1. Identification of the Testing Laboratory Issuing the SAR Assessment Report ...............5
     2.2. Identification of the Client...........................................................................................5
     2.3. Identification of the Manufacturer...............................................................................5


3. EQUIPMENT UNDER INVESTIGATION (EUI)...................................................................6

     3.1. Identification of the Equipment under Investigation ...................................................6


4. SUBJECT OF INVESTIGATION ........................................................................................7

     4.1. The IEEE Standard C95.1 and the FCC Exposure Criteria .......................................7
     4.2. Distinction Between Exposed Population, Duration of Exposure and Frequencies...7
     4.3. Distinction between Maximum Permissible Exposure and SAR Limits......................8
     4.4. SAR Limit ...................................................................................................................8


5. THE FCC MEASUREMENT PROCEDURE .......................................................................9

     5.1. General Requirements...............................................................................................9
     5.2. Test Positions ............................................................................................................9
     5.3. Body-worn and Other Configurations.........................................................................9
     5.4. Procedure for assessing the peak spatial-average SAR .........................................10
     5.5. Determination of the largest peak spatial-average SAR ..........................................12


6. THE MEASUREMENT SYSTEM ......................................................................................13

     6.1. Robot system specification ......................................................................................13
     6.2. Probe and amplifier specification .............................................................................14
     6.3. Phantoms.................................................................................................................14
     6.4. SAR measurement procedure .................................................................................15
     6.5. SARA2 Interpolation and Extrapolation schemes ....................................................15
     6.6. Interpolation of 2D area scan...................................................................................16
     6.7. Extrapolation of 3D scan..........................................................................................16

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                  CETECOM Inc. Š SAR Š 411 Dixon Landing Road Š Milpitas, CA 95035 Š U.S.A.


SAR Test Report No.
SAR_936_2005_FCC_2450MPAGH
Date of Report: 7/11/2005                                                                  Page 3 of 23

     6.8. Interpolation of 3D scan and volume averaging.......................................................16


7. UNCERTAINTY ASSESSMENT.......................................................................................18

     7.1. Measurement Uncertainty Budget ...........................................................................19


8. TEST RESULTS SUMMARY............................................................................................20

     8.1. Conducted Output Power.........................................................................................20
     8.2. Test Positions and Configurations ...........................................................................20
     8.3. SAR Results for BCM94318MPG ............................................................................20
     8.4. Bluetooth collocation results: ...................................................................................21
     8.5. Validation Check Results .........................................................................................22


9. REFERENCES..................................................................................................................23




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                  CETECOM Inc. Š SAR Š 411 Dixon Landing Road Š Milpitas, CA 95035 Š U.S.A.


SAR Test Report No.
SAR_936_2005_FCC_2450MPAGH
Date of Report: 7/11/2005                                                                  Page 4 of 23




1.       Assessment

The Broadcom Corporation BCM94318MPAGH Broadcom 802.11ag Mini PCI Card in
host PC is in compliance with the limits for general population uncontrolled exposure
specified in FCC 2.1093. The device was tested according to measurement standards and
procedures specified in FCC OET Bulletin 65, Supplement C (Edition 01-01) and IEEE
P1528/D1.2, April 21, 2003.




                           7/11/2005                                                                        7/11/2005
                          Pete Krebill                                                                   Lothar Schmidt
                          Project Leader                                                                  Test Lab Manager




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source not found.
                  CETECOM Inc. Š SAR Š 411 Dixon Landing Road Š Milpitas, CA 95035 Š U.S.A.


SAR Test Report No.
SAR_936_2005_FCC_2450MPAGH
Date of Report: 7/11/2005                                                                  Page 5 of 23

2.       Administrative Data

     2.1. Identification of the Testing Laboratory Issuing the SAR Assessment Report

 Company Name:                                                              CETECOM Inc.
 Department:                                                                SAR
 Address:                                                                   411 Dixon Landing Road
                                                                            Milpitas, CA 95035
                                                                            U.S.A.
 Telephone:                                                                 +1 (408) 586 6200
 Fax:                                                                       +1 (408) 586 6299
 Responsible Test Lab Manager:                                              Lothar Schmidt


     2.2. Identification of the Client

Applicant’s Name:                         Broadcom Corporation
Address:                                  190 Mathilda Place
                                          Sunnyvale, 94086, USA
Contact Person:                           Dan Lawless
Phone No.                                 408 922 5870
Fax:                                      408 543 3399
e-mail:                                   dlawless@broadcom.com



     2.3. Identification of the Manufacturer

Manufactured by client shown above.




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                  CETECOM Inc. Š SAR Š 411 Dixon Landing Road Š Milpitas, CA 95035 Š U.S.A.


SAR Test Report No.
SAR_936_2005_FCC_2450MPAGH
Date of Report: 7/11/2005                                                                  Page 6 of 23

3.       Equipment under Investigation (EUI)

     3.1. Identification of the Equipment under Investigation

 Product Type                                       Broadcom 802.11ag Mini PCI Card
 Marketing Name:                                    Broadcom 802.11ag Mini PCI Card
 Model No:                                          BCM94318MPAGH
 Host PC:
 FCC-ID:                                            QDS-BRCM1017
 Frequency Range:                                   2400-2483.5MHz
                                                    DSSS and OFDM (Orthogonal Frequency Division Multippl
 Type(s) of Modulation:
                                                    exing)
 Number of Channels:                                1-11
 Output Power:                                      19.1 dBm (81.3 mW) peak conducted power




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                  CETECOM Inc. Š SAR Š 411 Dixon Landing Road Š Milpitas, CA 95035 Š U.S.A.


SAR Test Report No.
SAR_936_2005_FCC_2450MPAGH
Date of Report: 7/11/2005                                                                  Page 7 of 23

4.       Subject of Investigation
The BCM94318MPAGH is a Broadcom 802.11ag Mini PCI Card from Broadcom Corporation
operating in the 2400-2483.5MHz frequency range. The device has two diversity antennas. For
testing the device will be installed in a laptop PC.

The objective of the measurements done by Cetecom Inc. was the dosimetric assessment of one
device. The tests were performed in configurations for devices operated next to a person’s body.
The examinations were carried out with the dosimetric assessment system SARA2 described
below.


     4.1. The IEEE Standard C95.1 and the FCC Exposure Criteria

In the USA the recent FCC exposure criteria [FCC 2001] are based upon the IEEE Standard
C95.1 [IEEE 1999]. The IEEE standard C95.1 sets limits for human exposure to radio frequency
electromagnetic fields in the frequency range 3 kHz to 300 GHz.


     4.2. Distinction Between Exposed Population, Duration of Exposure and
          Frequencies

The American Standard [IEEE 1999] distinguishes between controlled and uncontrolled
environment. Controlled environments are locations where there is exposure that may be incurred
by persons who are aware of the potential for exposure as a concomitant of employment or by
other cognizant persons. Uncontrolled environments are locations where there is the exposure of
individuals who have no knowledge or control of their exposure. The exposures may occur in
living quarters or workplaces. For exposure in controlled environments higher field strengths are
admissible. In addition the duration of exposure is considered. Due to the influence of frequency
on important parameters, as the penetration depth of the electromagnetic fields into the human
body and the absorption capability of different tissues, the
limits in general vary with frequency.




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                                             CETECOM Inc. Š SAR Š 411 Dixon Landing Road Š Milpitas, CA 95035 Š U.S.A.


SAR Test Report No.
SAR_936_2005_FCC_2450MPAGH
Date of Report: 7/11/2005                                                                  Page 8 of 23



    4.3. Distinction between Maximum Permissible Exposure and SAR Limits

The biological relevant parameter describing the effects of electromagnetic fields in the
frequency range of interest is the specific absorption rate SAR (dimension: power/mass). It is a
measure of the power absorbed per unit mass. The SAR may be spatially averaged over the total
mass of an exposed body or its parts. The SAR is calculated from the r.m.s. electric field strength
E inside the human body, the conductivity σ and the mass density ρ of the biological tissue:

                  E2             ∂T
SAR =         σ   — =       c—
                    ρ            ∂t      t →0+


The specific absorption rate describes the initial rate of temperature rise ∂T / ∂t as a function of
the specific heat capacity c of the tissue. A limitation of the specific absorption rate prevents an
excessive heating of the human body by electromagnetic energy.

As it is sometimes difficult to determine the SAR directly by measurement (e.g. whole body
averaged SAR), the standard specifies more readily measurable maximum permissible exposures
in terms of external electric E and magnetic field strength H and power density S, derived from
the SAR limits. The limits for E, H and S have been fixed so that even under worst case
conditions, the limits for the specific absorption rate SAR are not exceeded.

For the relevant frequency range the maximum permissible exposure may be exceeded if the
exposure can be shown by appropriate techniques to produce SAR values below the
corresponding limits.


    4.4. SAR Limit

In this report the comparison between the American exposure limits and the measured data is
made using the spatial peak SAR; the power level of the device under test guarantees that the
whole body averaged SAR is not exceeded.

Having in mind a worst case consideration, the SAR limit is valid for uncontrolled environment
and mobile respectively portable transmitters. According to Table 1 the SAR values have to be
averaged over a mass of 1 g (SAR1g) with the shape of a cube.

               Standard                                                           Status                 SAR limit (W/kg )
               IEEE C95.1                                                        In force                       1.6

Table 1: Relevant spatial peak SAR limit averaged over a mass of 1 g



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                                             CETECOM Inc. Š SAR Š 411 Dixon Landing Road Š Milpitas, CA 95035 Š U.S.A.


SAR Test Report No.
SAR_936_2005_FCC_2450MPAGH
Date of Report: 7/11/2005                                                                  Page 9 of 23

5.       The FCC Measurement Procedure
The Federal Communications Commission (FCC) has published a report and order on the 1st of
August 1996 [FCC 1996], which requires routine dosimetric assessment of mobile telecom-
communications devices, either by laboratory measurement techniques or by computational
modeling, prior to equipment authorization or use. In 2001 the Commission’s Office of
Engineering and Technology has released Edition 01-01 of Supplement C to OET Bulletin 65.
This revised edition, which replaces Edition 97-01, provides additional guidance and information
for evaluating compliance of mobile and portable devices with FCC limits for human exposure
to radiofrequency emissions [FCC 2001].


     5.1. General Requirements

The test shall be performed in a laboratory with an environment which avoids influence on SAR
measurements by ambient EM sources and any reflection from the environment itself. The
ambient temperature shall be in the range of 20°C to 26°C and 30-70% humidity.


     5.2. Test Positions



     5.3. Body-worn and Other Configurations

Phantom Requirements
For body-worn and other configurations a flat phantom shall be used which is comprised of
material with electrical properties similar to the corresponding tissues.

Test Position
The body-worn configurations shall be tested with the supplied accessories (belt-clips, holsters,
etc.) attached to the device in normal use configuration. Devices with a headset output shall be
tested with a connected headset.

Test to be Performed
For purpose of determining test requirements, accessories may be divided into two categories:
those that do not contain metallic components and those that do. For multiple accessories that do
not contain metallic components, the device may be tested only with that accessory which
provides the closest spacing to the body. For multiple accessories that contain metallic
components, the device must be tested with each accessory that contains a unique metallic
component. If multiple accessories share an identical metallic component, only the accessory that
provides the closest spacing to the body must be tested. If the manufacturer provides none body-
worn accessories a separation distance of 1.5 cm between the back of the device and the flat
phantom is recommended. Other separation distances may be used, but they shall not exceed 2.5
cm. In these cases, the device may use body-worn accessories that provide a separation distance
greater than that tested for the device provided however that the accessory contains no metallic
components.

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                                             CETECOM Inc. Š SAR Š 411 Dixon Landing Road Š Milpitas, CA 95035 Š U.S.A.


SAR Test Report No.
SAR_936_2005_FCC_2450MPAGH
Date of Report: 7/11/2005                                                                  Page 10 of 23



For devices with retractable antenna the SAR test shall be performed with the antenna fully
extended and fully retracted. Other factors that may affect the exposure shall also be tested. For
example, optional antennas or optional battery packs which may significantly change the volume,
lengths, flip open/closed, etc. of the device, or any other accessories which might have the
potential to considerably increase the peak spatial-average SAR value.


    5.4. Procedure for assessing the peak spatial-average SAR

     Step 1: Power reference measurement:
     Prior to the SAR test, a local SAR measurement should be taken at a user-selected spatial
     reference point to monitor power variations during testing. For example, this power reference
     point can be spaced 10 mm or less in the normal direction from the liquid-shell interface and
     within ± 10 mm transverse to the normal line at the ear reference point.
     Step 2: Area scan
     The measurement procedures for evaluating SAR associated with wireless handsets typically
     start with a coarse measurement grid in order to determine the approximate location of the
     local peak SAR values. This is referred to as the "area scan" procedure. The SAR
     distribution is scanned along the inside surface of typically half of the head of the phantom
     but at least larger than the areas projected (normal to the phantom’s surface) by the handset
     and antenna. An example grid is given in Figure 4. The distance between the measured
     points and phantom surface should be less than 8 mm, and should remain constant (variation
     less than ± 1 mm) during the entire scan in order to determine the locations of the local peak
     SAR with sufficient precision. The distance between the measurement points should enable
     the detection of the location of local maximum with an accuracy of better than half the linear
     dimension of the tissue cube after interpolation. The resolution can also be tested using the
     functions in Annex E (see E.5.2). The approximate locations of the peak SARs should be
     determined from area scan. Since a given amplitude local peak with steep gradients may
     produce lower spatial-average SAR than slightly lower amplitude peaks with less steep
     gradients, it is necessary to evaluate the other peaks as well. However, since the spatial
     gradients of local SAR peaks are a function of wavelength inside the tissue simulating liquid
     and incident magnetic field strength, it is not necessary to evaluate peaks that are less than –
     2dB of the local maximum. Two-dimensional spline algorithms [Press, et al, 1996],
     [Brishoual, 2001] are typically used to determine the peaks and gradients within the scanned
     area. If the peak is closer than one-half of the linear dimension of the 1 g or 10 g tissue cube
     to the scan border, the measurement area should be enlarged if possible, e.g., by tilting the
     probe or the phantom (see Figure 5).




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                                             CETECOM Inc. Š SAR Š 411 Dixon Landing Road Š Milpitas, CA 95035 Š U.S.A.


SAR Test Report No.
SAR_936_2005_FCC_2450MPAGH
Date of Report: 7/11/2005                                                                  Page 11 of 23




Figure 4 – Example of an area scan including the position of the handset. The scanned area
(white dots) should be larger than the area projected by the handset and antenna.

Step 3: Zoom scan
In order to assess the peak spatial SAR values averaged over a 1 g and 10 g cube, fine resolution
volume scans, called "zoom scans", are performed at the peak SAR locations determined during
the “area scan.” The zoom scan volume should have at least 1.5 times the linear dimension of
either a 1 g or a 10 g tissue cube for whichever peak spatial-average SAR is being evaluated. The
peak local SAR locations that were determined in the area scan (interpolated value) should be on
the centerline of the zoom scans. The centerline is the line that is normal to the surface and in the
center of the volume scan. If this is not possible, the zoom scan can be shifted but not by more
than half the dimension of the 1 g or a 10 g tissue cube.
The maximum spatial-average SAR is determined by a numerical analysis of the SAR values
obtained in the volume of the zoom scan, whereby interpolation (between measured points) and
extrapolation (between surface and closest measured points) routines should be applied. A 3-D-
spline algorithm [Press, et al, 1996], [Kreyszig, 1983], [Brishoual, 2001] can be used for
interpolation and a trapezoidal algorithm for the integration (averaging). Scan resolutions of
larger than 2 mm can be used provided the uncertainty is evaluated according to E (see E.5).
In some areas of the phantom, such as the jaw and upper head region, the angle of the probe with
respect to the line normal to the surface might become large, e.g., at angles larger than ± 30º (see
Figure 5), which may increase the boundary effect to an unacceptable level. In these cases, a
change in the orientation of the probe and/or the phantom is recommended during the zoom scan
so that the angle between the probe housing tube and the line normal to the surface is
significantly reduced (<30º).



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SAR Test Report No.
SAR_936_2005_FCC_2450MPAGH
Date of Report: 7/11/2005                                                                  Page 12 of 23

     Step 4: Power reference measurement
     The local SAR should be measured at exactly the same location as in Step 1. The absolute
     value of the measurement drift (the difference between the SAR measured in Step 4 and Step
     1) should be recorded in the uncertainty budget. It is recommended that the drift be kept
     within ± 5%. If this is not possible, even with repeat testing, additional information may be
     used to demonstrate the power stability during the test. Power reference measurements can be
     taken after each zoom scan, if more than one zoom scan is needed. However, the drift should
     always be referred to the initial state with fully charged battery.


    5.5. Determination of the largest peak spatial-average SAR

     In order to determine the largest value of the peak spatial-average SAR of a handset, all
     device positions, configurations and operational modes should be tested for each frequency
     band according to steps 1 to 3 below.
     Step 1: The tests of 6.4 should be conducted at the channel that is closest to the center of the
     transmit frequency band (fc) for:
     a) all device positions (cheek and tilt, for both left and right sides of the SAM phantom,
     b) all configurations for each device position in (a), e.g. antenna extended and retracted, and
     c) all operational modes for each device position in (a) and configuration in (b) in each
        frequency band, e.g. analog and digital.
      If more than three frequencies need to be tested, (i.e., Nc > 3), then all frequencies,
      configurations and modes must be tested for all of the above positions.
     Step 2: For the condition providing highest spatial peak SAR determined in Step 1 conduct
     all tests of 6.4 at all other test frequencies, e.g. lowest and highest frequencies. In addition,
     for all other conditions (device position, configuration and operational mode) where the
     spatial peak SAR value determined in Step 1 is within 3dB of the applicable SAR limit, it is
     recommended that all other test frequencies should be tested as well1.
     Step 3: Examine all data to determine the largest value of the peak spatial-average SAR
     found in Steps 1 to 2.




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                                             CETECOM Inc. Š SAR Š 411 Dixon Landing Road Š Milpitas, CA 95035 Š U.S.A.


SAR Test Report No.
SAR_936_2005_FCC_2450MPAGH
Date of Report: 7/11/2005                                                                  Page 13 of 23

6.       The Measurement System

     6.1. Robot system specification

The SAR measurement system being used is the IndexSAR SARA2 system, which consists of a
Mitsubishi RV-E2 6-axis robot arm and controller, IndexSAR probe and amplifier and SAM
phantom Head Shape. The robot is used to articulate the probe to programmed positions inside
the phantom head to obtain the SAR readings from the DUT.

The system is controlled remotely from a PC, which contains the software to control the robot
and data acquisition equipment. The software also displays the data obtained from test scans.




                           Figure 5: Schematic diagram of the SAR measurement system

The position and digitised shape of the phantom heads are made available to the software for
accurate positioning of the probe and reduction of set-up time.
The SAM phantom heads are individually digitised using a Mitutoyo CMM machine to a
precision of 0.001mm. The data is then converted into a shape format for the software,
providing an accurate description of the phantom shell.

In operation, the system first does an area (2D) scan at a fixed depth within the liquid from the
inside wall of the phantom. When the maximum SAR point has been found, the system will then
carry out a 3D scan centred at that point to determine volume averaged SAR level.
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                                             CETECOM Inc. Š SAR Š 411 Dixon Landing Road Š Milpitas, CA 95035 Š U.S.A.


SAR Test Report No.
SAR_936_2005_FCC_2450MPAGH
Date of Report: 7/11/2005                                                                  Page 14 of 23

    6.2. Probe and amplifier specification


IXP-050 Indexsar isotropic immersible SAR probe
The probes are constructed using three orthogonal dipole sensors arranged on an interlocking,
triangular prism core. The probes have built-in shielding against static charges and are contained
within a PEEK cylindrical enclosure material at the tip. Probe calibration is described in the
probe’s calibration certificate (see appendix C.). The system uses diode compression potential
(DCP) to determine SAR values for different types of modulation. Crest factor is not used for
determining SAR values. The DCP for different types of modulation is determined during the
probe calibration procedure. For a more detailed explanation see IndexSAR Immesible SAR Probe
Calibration Report included in Appendix C of this report.

IXP-010 Amplifier
The amplifier unit has a multi-pole connector to connect to the probe and a multiplexer selects
between the 3-channel single-ended inputs. A 16-bit AtoD converter with programmable gain is
used along with an on-board micro-controller with non-volatile firmware. Battery life is around
150 hours and data are transferred to the PC via 3m of duplex optical fibre and a self-powered
RS232 to optical converter.


    6.3. Phantoms

The Specific Anthropomorphic Mannequin (SAM) Upright Phantom is fabricated using moulds
generated from the CAD files as specified by CENELEC EN50361. It is mounted via a rotation
base to a supporting table, which also holds the robotic positioner. The phantom and robot
alignment is assured by both mechanical and laser registration systems. The box phantom used
for body testing and for validation is manufactured from Perspex. The material is 2 mm in
thickness on the test surfaces and 4 mm in thickness on the other surfaces. Its dimensions are:
X=21 cm., Y=20.5 cm., Z=16 cm.




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SAR Test Report No.
SAR_936_2005_FCC_2450MPAGH
Date of Report: 7/11/2005                                                                  Page 15 of 23



    6.4. SAR measurement procedure




                      Figure 6: Principal components of the SAR measurement test bench

The major components of the test bench are shown in the picture above. A test set and dipole
antenna control the handset via an air link and a low-mass phone holder can position the phone at
either ear. Graduated scales are provided to set the phone in the 15 degree position. The upright
phantom head holds approx. 7 litres of simulant liquid. The phantom is filled and emptied
through a 45mm diameter penetration hole in the top of the head.

After an area scan has been done at a fixed distance of 8mm from the surface of the phantom on
the source side, a 3D scan is set up around the location of the maximum spot SAR. First, a point
within the scan area is visited by the probe and a SAR reading taken at the start of testing. At the
end of testing, the probe is returned to the same point and a second reading is taken. Comparison
between these start and end readings enables the power drift during measurement to be assessed.


    6.5. SARA2 Interpolation and Extrapolation schemes

(see support document IXS-0202)
SARA2 software contains support for both 2D cubic B-spline interpolation as well as 3D cubic
B-spline interpolation. In addition, for extrapolation purposes, a general n-th order polynomial
fitting routine is implemented following a singular value decomposition algorithm presented in
[4]. A 4th order polynomial fit is used by default for data extrapolation, but a linear-logarithmic
fitting function can be selected as an option. The polynomial fitting procedures have been tested
by comparing the fitting coefficients generated by the SARA2 procedures with those obtained
using the polynomial fit functions of Microsoft Excel when applied to the same test input data.

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SAR Test Report No.
SAR_936_2005_FCC_2450MPAGH
Date of Report: 7/11/2005                                                                  Page 16 of 23

    6.6. Interpolation of 2D area scan

The 2D cubic B-spline interpolation is used after the initial area scan at fixed distance from the
phantom shell wall. The initial scan data are collected with approx. 10mm spatial resolution and
spline interpolation is used to find the location of the local maximum to within a 1mm resolution
for positioning the subsequent 3D scanning.


    6.7. Extrapolation of 3D scan

For the 3D scan, data are collected on a spatially regular 3D grid having (by default) 6.4 mm
steps in the lateral dimensions and 3.5 mm steps in the depth direction (away from the source).
SARA2 enables full control over the selection of alternative step sizes in all directions.

The digitised shape of the head is available to the SARA2 software, which decides which points
in the 3D array are sufficiently well within the shell wall to be ‘visited’ by the SAR probe. After
the data collection, the data are extrapolated in the depth direction to assign values to points in
the 3D array closer to the shell wall. A notional extrapolation value is also assigned to the first
point outside the shell wall so that subsequent interpolation schemes will be applicable right up to
the shell wall boundary.



    6.8. Interpolation of 3D scan and volume averaging

The procedure used for defining the shape of the volumes used for SAR averaging in the SARA2
software follow the method of adapting the surface of the ‘cube’ to conform with the curved
inner surface of the phantom (see Appendix D in FCC Supplement C edition 01-01 to OET
Bulletin 65 edition 97-01). This is called, here, the conformal scheme.

For each row of data in the depth direction, the data are extrapolated and interpolated to less than
1mm spacing and average values are calculated from the phantom surface for the row of data
over distances corresponding to the requisite depth for 10g and 1g cubes. This results in two 2D
arrays of data, which are then cubic B-spline interpolated to sub mm lateral resolution. A search
routine then moves an averaging square around through the 2D array and records the maximum
value of the corresponding 1g and 10g volume averages. For the definition of the surface in this
procedure, the digitised position of the headshell surface is used for measurement in head-shaped
phantoms. For measurements in rectangular, box phantoms, the distance between the phantom
wall and the closest set of gridded data points is entered into the software. For measurements in
box-shaped phantoms, this distance is under the control of the user. The effective distance must
be greater than 2.5mm as this is the tip-sensor distance and to avoid interface proximity effects, it
should be at least 5mm. A value of 6 or 8mm is recommended. This distance is called dbe.

For automated measurements inside the head, the distance cannot be less than 2.5mm, which is
the radius of the probe tip and to avoid interface proximity effects, a minimum clearance distance
of x mm is retained. The actual value of dbe will vary from point to point depending upon how

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                                             CETECOM Inc. Š SAR Š 411 Dixon Landing Road Š Milpitas, CA 95035 Š U.S.A.


SAR Test Report No.
SAR_936_2005_FCC_2450MPAGH
Date of Report: 7/11/2005                                                                  Page 17 of 23

the spatially-regular 3D grid points fit within the shell. The greatest separation is when a grid
point is just not visited due to the probe tip dimensions. In this case the distance could be as large
as the step-size plus the minimum clearance distance (i.e with x=5 and a step size of 3.5, dbe will
be between 3.5 and 8.5mm).

The default step size (dstep) used is 3.5mm, but this is under user-control. The compromise is
with time of scan, so it is not practical to make it much smaller or scan times become long and
power-drop influences become larger.

The robot positioning system specification for the repeatability of the positioning (dss) is +/-
0.04mm.

The phantom shell is made by an industrial moulding process from the CAD files of the SAM
shape, with both internal and external moulds. For the upright phantoms, the external shape is
subsequently digitised on a Mitutoyo CMM machine (Euro an ultrasonic sensor indicate that the
shell thickness (dph) away from the ear is 2.0 +/- 0.1mm. The ultrasonic measurements were
calibrated using additional mechanical measurements on available cut surfaces of the phantom
shells. See support document IXS-020x.

For the upright phantom, the alignment is based upon registration of the rotation axis of the
phantom on its 253mm diameter baseplate bearing and the position of the probe axis when
commanded to go to the axial position. A laser alignment tool is provided (procedure detailed
elsewhere). This enables the registration of the phantom tip (dmis) to be assured to within
approx. 0.2mm. This alignment is done with reference to the actual probe tip after installation and
probe alignment. The rotational positioning of the phantom is variable – offering advantages for
special studies, but locating pins ensure accurate repositioning at the principal positions (LH and
RH ears).




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                                             CETECOM Inc. Š SAR Š 411 Dixon Landing Road Š Milpitas, CA 95035 Š U.S.A.


SAR Test Report No.
SAR_936_2005_FCC_2450MPAGH
Date of Report: 7/11/2005                                                                  Page 18 of 23

7.       Uncertainty Assessment
Measurement uncertainty values were evaluated for SAR measurements performed by Cetecom
Inc. The uncertainty values for components specified in FCC Supplement C (01-01) to OET
Bulletin 65 (97-01) were evaluated according to the procedures of IEEE 1528-200X December
29, 2002, NIST 1297 1994 edition and ISO Guide to the Expression of Uncertainty in
Measurements (GUM).




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                                             CETECOM Inc. Š SAR Š 411 Dixon Landing Road Š Milpitas, CA 95035 Š U.S.A.


SAR Test Report No.
SAR_936_2005_FCC_2450MPAGH
Date of Report: 7/11/2005                                                                  Page 19 of 23


    7.1. Measurement Uncertainty Budget
                                                                                                                                       g=      k
                        a                                  b               c              d              e = f(d,k)      f
                                                                                                                                     cxf/e
                                                                                                                                       1-g
                 Uncertainty                                             Tol.           Prob.                            ci                    vi
                                                         Sec.                                              Div.                        ui
                 Component                                              (± %)           Dist.                          (1-g)
                                                                                                                                      (±%)
Measurement System
Probe Calibration                                        E2.1             3.6             N                  1           1             3.6     ∞

                                                                                                            √3                                 ∞
                                                                                                                               1/2
Axial Isotropy                                           E2.2            4.23             R                           (1-cp)          0.00

Hemispherical Isotropy                                   E2.2            10.7             R                 √3          √cp           6.18     ∞
Boundary Effect                                          E2.3             1.7             R                 √3           1            0.98     ∞
Linearity                                                E2.4            2.92             R                 √3           1            1.69     ∞
System Detection Limits                                  E2.5            0.00             R                 √3           1            0.00     ∞
Readout Electronics                                      E2.6            0.00             N                  1           1            0.00     ∞
Response Time                                            E2.7            0.00             R                 √3           1            0.00     ∞
Integration Time                                         E2.8             0.0             R                 √3           1            0.23     ∞
RF Ambient Conditions                                    E6.1            0.00             R                 √3           1            0.00     ∞
Probe Positioner Mechanical Tolerance                    E6.2            0.57             R                 √3           1            0.33     ∞
Probe Positioning with respect to Phantom
                                                         E6.3            1.43             R                 √3           1            0.83     ∞
Shell

Extrapolation, interpolation and Integration
                                                         E5.2             3.6             R                 √3           1            2.08     ∞
Algorithms for Max. SAR Evaluation

Test sample Related
Test Sample Positioning                                  E4.2            4.81             N                  1           1            4.81     29
Device Holder Uncertainty                                E4.1            0.00             N                  1           1            0.00      0

Output Power Variation - SAR drift
                                                         6.6.2            5.0             R                 √3           1            2.89     ∞
measurement

Phantom and Tissue Parameters
Phantom Uncertainty (shape and
                                                         E3.1            1.43             R                 √3           1            0.83     ∞
thickness tolerances)
Liquid Conductivity Target - tolerance                   E3.2             5.0             R                 √3          0.7           2.02     ∞
Liquid Conductivity - measurement
                                                         E3.3             2.0             R                 √3          0.7           0.81     ∞
uncertainty
Liquid Permittivity Target tolerance                     E3.2             5.0             R                 √3          0.6           1.73     ∞
Liquid Permittivity - measurement
                                                         E3.3             1.0             R                 √3          0.6           0.35     ∞
uncertainty
Combined Standard Uncertainty                                                           RSS                                          ± 10.0%
Expanded Uncertainty                                                                     k=
                                                                                                                                     ± 20.1%
(95% CONFIDENCE INTERVAL)                                                             2.00705




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                                             CETECOM Inc. Š SAR Š 411 Dixon Landing Road Š Milpitas, CA 95035 Š U.S.A.


SAR Test Report No.
SAR_936_2005_FCC_2450MPAGH
Date of Report: 7/11/2005                                                                  Page 20 of 23

8.       Test results summary

     8.1. Conducted Output Power

Prior to testing the conducted RF output power was measured. The results are shown below.

           Channel 1:              28.59 dBm
           Channel 6:              28.95 dBm
           Channel 11:             28.57 dBm


     8.2. Test Positions and Configurations

The device was installed in a HP model: HSTNN-CO2C laptop PC. The device was set to
transmit without antenna diversity. The PC can be configured as a normal laptop PC or as a tablet
PC. Both configurations were tested. The area scan of the measurement was centered near the
transmitting antenna. The worst case mode was determined to be 802.11b with a rate of 1
MB/sec.


     8.3. SAR Results for BCM94318MPAGH

       Transmit                 Position             Device                    Max.             Area scan     Positioning
      Antenna /                                     Channel                   1g SAR              (See         photo (See
     Configuration                                  Number /                  (W/kg)           Appendix A)    Appendix B)
                                                   Frequency
                                                     (MHz)
   Main / Normal                   Lap            Mid #6 / 2437                 0.062                Plot 1     Photo 7
   Main / Tablet                   Lap            Mid #6 / 2437                 0.060                Plot 2     Photo 8
    Aux / Tablet                   Lap            Mid #6 / 2437                 0.097                Plot 3     Photo 9
    Aux / Tablet                   Lap            Low #1 / 2412                 0.094                Plot 4     Photo 9
                                                   High #11 /
     Aux / Tablet                  Lap                                          0.075                Plot 5     Photo 9
                                                      2462
                                                   High #13 /
     Aux / Tablet                  Lap                                          0.022                Plot 6     Photo 9
                                                      2472




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                                             CETECOM Inc. Š SAR Š 411 Dixon Landing Road Š Milpitas, CA 95035 Š U.S.A.


SAR Test Report No.
SAR_936_2005_FCC_2450MPAGH
Date of Report: 7/11/2005                                                                  Page 21 of 23




    8.4. Bluetooth collocation results:

Scans were performed with the Bluetooth module transmitting. The PC was in the lap position
during these scans. There was no SAR detectable above the ambient level of the host PC. That
ambient level was 0.008 W/kg. This value is added to the SAR values measured during 802.11
scans and compared to the SAR limit. The highest value is shown below.

Highest 802.11 SAR                   +     Bluetooth SAR = Colocated SAR
0.097 W/kg                                 0.008 W/kg    = 0.105 W/kg




Error!   Reference This report shall not be reproduced except in full without the written approval of:
source not found.
                                             CETECOM Inc. Š SAR Š 411 Dixon Landing Road Š Milpitas, CA 95035 Š U.S.A.


SAR Test Report No.
SAR_936_2005_FCC_2450MPAGH
Date of Report: 7/11/2005                                                                  Page 22 of 23

[W/kg]]) Temperature


    8.5. Validation Check Results

Prior to formal testing at each frequency a system verification was performed in accordance with
IEEE 1528. The balanced dipole source was placed at the specified distance in horizontal
orientation. All of the testing described in this report was performed within 24 hours of the
system verification. The following results were obtained:

                                                                                                                        Difference
                                                                                   Max                       1 Watt
                                                                                                                         reference
                                               CW input                Max     measured1g                   reference
                                                                                                                        SAR value
                       Frequency               at dipole            measured1g    SAR                      SAR value
       Date                                                                                                                  to
                         (MHz)                    feed                 SAR     normalized                  from IEEE
                                                                                                                        normalized
                                                (Watts)              (W/kg)     to 1 Watt                     1528
                                                                                                                           SAR
                                                                                 (W/kg)                      (W/kg)
    6/9/05                  2450                      1                  53.09                  53.09        52.4        +1.32%

/k
g] (




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                                             CETECOM Inc. Š SAR Š 411 Dixon Landing Road Š Milpitas, CA 95035 Š U.S.A.


SAR Test Report No.
SAR_936_2005_FCC_2450MPAGH
Date of Report: 7/11/2005                                                                  Page 23 of 23

9.       References
 [FCC 2001] Federal Communications Commission: Evaluating Compliance with FCC
Guidelines for Human Exposure to Radiofrequency Electromagnetic Fields,
Supplement C (Edition 01-01) to OET Bulletin 65 (Edition 97-01), FCC, 2001.
[IEEE 1999] IEEE Std C95.1-1999: IEEE Standard for Safety Levels with Respect to
Human Exposure to Radio Frequency Electromagnetic Fields, 3 kHz to
300 GHz, Inst. of Electrical and Electronics Engineers, Inc., 1999.
[IEEE 200x] IEEE Std 1528-200x: DRAFT Recommended Practice for Determining the
Peak Spatial-Average Specific Absorption Rate (SAR) in the Human Body
Due to Wireless Communications Devices: Experimental Techniques. Draft
6.2, Inst. of Electrical and Electronics Engineers, Inc., 2000.
[NIST 1994] NIST: Guidelines for Evaluating and Expressing the Uncertainty of NIST
Measurement Results, Technical Note 1297 (TN1297), United States
Department of Commerce Technology Administration, National Institute of
Standards and Technology, 1994.




Error!   Reference This report shall not be reproduced except in full without the written approval of:
source not found.
                                             CETECOM Inc. Š SAR Š 411 Dixon Landing Road Š Milpitas, CA 95035 Š U.S.A.



Document Created: 2005-07-14 06:31:03
Document Modified: 2005-07-14 06:31:03

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