Test Report Intel Far Field EIRP Measurement

FCC ID: PD917265NG

Test Report

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FCCID_2741596

Test Report N°15052702.TR01 Rev. 04

Table of Contents
1. Standards, reference documents and applicable test methods ............................................... 3
2. General conditions, competences and guarantees .................................................................... 3
3. Environmental Conditions............................................................................................................. 3
4. Test samples ................................................................................................................................... 3
5. EUT features ................................................................................................................................... 4
6. Remarks and comments ................................................................................................................ 4
7. Test Verdicts summary .................................................................................................................. 4
8. Document Revision History .......................................................................................................... 4
Annex A. Test & System Description ............................................................................................. 5
A.1 TEST CONDITIONS ........................................................................................................................................ 5
A.2 MEASUREMENT SYSTEM ................................................................................................................................ 5
A.3 TEST EQUIPMENT LIST ................................................................................................................................... 5
A.4 MEASUREMENT UNCERTAINTY EVALUATION...................................................................................................... 6
A.4.1 Aperture Probe Gain Characterization ............................................................................................ 6
A.4.2 EUT Measurement. .......................................................................................................................... 6
A.5 POWER SENSOR CONSIDERATION AND PULSE RESPONSE...................................................................................... 7
Annex B. Test Results ...................................................................................................................... 8
B.1 DUTY CYCLE ................................................................................................................................................ 8
B.2 EIRP & POWER DENSITY ............................................................................................................................. 13
Annex C. Aperture Probe Antenna Characterization .................................................................. 17
C.1 DESCRIPTION OF THE ANTENNA..................................................................................................................... 17
C.2 DERIVATION OF CHARACTERIZATION EQUATIONS .............................................................................................. 17
C.3 CHARACTERIZATION PROCEDURE ................................................................................................................... 18
C.4 CHARACTERIZATION RESULTS AND VALIDATION ................................................................................................ 19
C.4.1 Far-Field Distance .......................................................................................................................... 19
C.4.2 Probe Gain ..................................................................................................................................... 19
C.4.3 Validation ...................................................................................................................................... 20
Annex D. Photographs ................................................................................................................... 21

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1. Standards, reference documents and applicable test methods
1. FCC 47 CFR part 2 – Subpart C – §15.255 Operation within the band 57-64 GHz.

2. General conditions, competences and guarantees
 Intel Mobile Communications Wireless RF Lab (Intel WRF Lab) is a testing laboratory accredited
by the American Association for Laboratory Accreditation (A2LA).
 Intel Mobile Communications Wireless RF Lab (Intel WRF Lab) is an Accredited Test Firm listed
by the FCC, with Designation Number FR0011.
 Intel WRF Lab only provides testing services and is committed to providing reliable, unbiased
test results and interpretations.
 Intel WRF Lab is liable to the client for the maintenance of the confidentiality of all information
related to the item under test and the results of the test.
 Intel WRF Lab has developed calibration and proficiency programs for its measurement
equipment to ensure correlated and reliable results to its customers.
 This report is only referred to the item that has undergone the test.
 This report does not imply an approval of the product by the Certification Bodies or competent
Authorities.
 Complete or partial reproduction of the report cannot be made without written permission of Intel
WRF Lab.

3. Environmental Conditions
 At the site where the measurements were performed the following limits were not exceeded
during the tests:

Temperature 22ºC ± 2ºC

Humidity 50% ± 5%

4. Test samples

Date of
Sample Control # Description Model Serial #
reception
15052702.S01 Laptop Dell P58G ZAU7002850 2015-05-21
#01 CN-04H6NV-
AC/DC
15052702.S02 Dell DA45NM131 48661-46R-11M1- 2015-05-21
Adapter
A01

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5. EUT features
These are the detailed bands and modes supported by the equipment under Test:

WiGig 60GHz (58.320 – 62.640 GHz)

802.11b/g/n 2.4GHz (2400.0 – 2483.5 MHz)

802.11a/n/ac 5.2GHz (5150.0 – 5350.0 MHz)
5.6GHz (5470.0 – 5725.0 MHz)
5.8GHz (5725.0 – 5850.0 MHz)

BDR/EDR v2.1 2.4GHz (2400.0 – 2483.5 MHz)
Bluetooth LE v4.0

6. Remarks and comments
1. This report documents the results of radiated measurements of the EIRP and the resulting
power density of a radio device operating in the 60 GHz unlicensed band.
2. Dell model P58G is the regulatory model number. This identical host is also marketed under
the name Dell Latitude 7350. In the report we refer only to P58G model.

7. Test Verdicts summary
N/A

8. Document Revision History

Revision # Date Modified by Details
Rev. 00 2015-05-29 W. El Hajj First Issue
Rev. 01 2015-06-29 W. El Hajj Editorial changes
Added measurements for channels 1 and 3, and Power
Added Sensor pulse response measurement
Rev. 02 2015-07-22 W. El Hajj Editorial changes.
Modifications to address FCC comments:
 Comment 1: The word “either” in the section B.1 is
deleted.
 Comment 2: In the section B.2, added explanation
on the way how the free-space attenuation is used
in the calculation.
 Comment 3: Captions added below each graph in
Page 16.
Rev. 03 2015-08-05 W. El Hajj Editorial changes: A statement is added in paragraph 6
concerning the Dell model number information.
Rev. 04 2015-08-31 J.M. Fortes Added column for conducted power in results tables in
B.2.

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Annex A. Test & System Description
A.1 Test Conditions
The EUT is an Intel Wireless Gigabit radio model 17265NGW, FCC ID PD917265NG, installed in a
Dell P58G convertible 2 in 1 laptop.
The antenna is an integral phased array antenna with a maximum gain of 15.45 dBi.
The DUT was set to transmit at highest power on MCS1 with 50% duty cycle using proprietary
software (Intel DRTU version 1.7.6-1123).

A.2 Measurement system
A Thorlabs Motorized Travel Stage controlled by software is used to maintain a consistent and
accurate placement of the probe.
Absorber material covering up to 110GHz is placed around the support structures and alignment
fixture to reduce reflections, scattering and perturbations.
The Aperture Probe is aligned with the boresight of the EUT antenna. The probe is scanned over X / Y
/ Polarization to maximize the emissions level.
The channel power is measured and recorded for all channels, then Pt*Gt, Power density and EIRP
are calculated as described below.
The measurement distance is varied from 10 to 20 cm in 1-cm steps and the power and results of
subsequent calculations are recorded for each distance. The distance corresponds to the separation
between the antenna plane of the EUT and the aperture plane of the probe.

A.3 Test Equipment List

Cal. Due
ID# Device Type/Model Serial Number Manufacturer Cal. Date
Date

Power Sensor Rohde &
0014 NRP-Z57 00152266 2015-05-06 2017-05-06
(DC -67 GHz) Schwarz

Rohde &
0015 Spectrum analyzer FSU67 100092 2013-11-12 2015-11-12
Schwarz

Rohde &
0016 Signal Generator SMF100A 102117 2014-03-11 2016-03-11
Schwarz

Standard Horn FH-SG-075-
0066 20012 RPG Calibration Not Required
Antenna 25

Aperture Probe
0331 15EWG1.85 J215060133 A-Info Characterized Internally
antenna
MULTIPLIER
0063 ASSEMBLY 40- AFM-40-220 394 RPG Calibration Not Required
220GHz

Note: The Duty cycle is measured using the FSU67 spectrum analyzer and a standard horn antenna.
The FSU67 covers (20Hz-67GHz) frequency range, therefore the measurement is performed directly
without a need to an external mixer.

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A.4 Measurement Uncertainty Evaluation
The Total Measurement Uncertainty is of 1.26 dB. This value is obtained by calculating first the
Aperture Probe Gain Measurement Uncertainty (see A.4.1) and then using this value with the other
uncertainty sources to deduce the total Uncertainty (see A.4.2).

A.4.1 Aperture Probe Gain Characterization
3 Antennas Gain Method / Probe Characterization
Expanded
Value Probability Sensitivity
Source of Uncertainty Divisor Uncertainty
[dB] Distribution Coefficient
[dB]
Mismatch VSWR SG Block 1.1 - TR 1.5 0.08 U-shaped 1.414 1 0.06
Mismatch VSWR TR 1.5 - PM 1.35 0.26 U-shaped 1.414 1 0.18
Insertion Loss transition 0.40 rectangular 1.732 1 0.23
Mismatch VSWR
0.02 U-shaped 1.414 1 0.01
SG Block 1.1 - Antenna Block 1.1
Mismatch VSWR
0.14 U-shaped 1.414 1 0.10
Antenna Block 1.1 - TR 2
Mismatch VSWR TR 2 - PM 1.35 0.44 U-shaped 1.414 1 0.31
Position of the phase centre
0.13 rectangular 1.732 1 0.08
(Receiving Ant.)
Linearity (included in Repeatability) 0.000 rectangular 1.732 1 0.00
Zero Offset 0.211 rectangular 1.732 1 0.12
Repeatability (Relative Power Meas.) 0.01 rectangular 1.732 1 0.01
Meas Noise 0.043 rectangular 1.732 1 0.02

Combined Standard Uncertainty 0.47
Expanded Uncertainty (k=2)* 0.93

A.4.2 EUT Measurement.
Expanded
Value Probability Sensitivity
Source of Uncertainty Divisor Uncertainty
[dB] Distribution Coefficient
[dB]
Meas. Antenna Gain Rx Aperture
0.93 rectangular 1.732 1 0.47
Probe
Mismatch VSWR Block Antenna 2 -
0.44 U-shaped 1.414 1 0.31
PM 1.35
Power Meter Accuracy 0.25 rectangular 1.732 1 0.14
Range Length (near/far field
0.00 rectangular 1.732 1 0.00
condition)
Position of the phase center
0.13 rectangular 1.732 1 0.08
(Receiving Ant.)
Ambient temperature impact 0.10 normal 1 1 0.10
Repeatability 0.20 normal 1 1 0.20
Zero Offset 0.144 rectangular 1.732 1 0.08
Meas Noise 0.019 rectangular 1.732 1 0.01

Combined Standard Uncertainty 0.63
Expanded Uncertainty (k=2)* 1.26

SG : Signal Generator TR : Transition PM : Power Meter

* The expanded Measurement Uncertainty with coverage factor (k=2) corresponds to a confidence level of 95%.

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A.5 Power Sensor Consideration and Pulse Response
The averaging settings of the power meter / power sensor combination must be adjusted to respond
properly to the modulation bursts and burst period.

The power sensor is connected to the microwave signal generator. The output frequency of the
generator is set to 60.48 GHz corresponding to EUT channel 2. The generator is adjusted for pulse
modulation using the nominal timing values for the Duty cycle across the Burst Period (500 msec ON,
1000 msec Period). The Duty cycle is verified by measurement (see figure below) using the FSU67
spectrum analyzer.

Duty Cycle
ON Time Period Duty Cycle
Description Correction
(ms) (ms) Linear
(dB)
Nominal Duty Cycle
500 1000 0.5 3
over Burst Period
Measured Nominal Duty Cycle
494.102564 996.794872 0.4957 3.0479
over Burst Period

The power meter averaging number is then adjusted to provide a stable measurement (after the
published settling time has elapsed).
Pulse modulation is then turned off, the delta between Modulation OFF and ON is measured, and
compared to the expected measured value of 10 * Log (Measured Nominal duty cycle across Burst
period) = 3.0479 dB.

An averaging number of 64000 provided measurements stable to within approximately 0.018 dB
(3.0479-3.03dB) for the EUT’s nominal pulse characteristics documented above. The power sensor
showed a measured difference of 3.03 dB, between CW and modulated.

Pulse Modulation Pulse Modulation Measured Difference
Description
OFF ON (dB)
Average Power (dBm) -29.63 -32.66 3.03

Note: The output average level of the mm-Wave generator is adjusted to be similar to the lowest
power value obtained during the EIRP measurement. This confirms the measurement averaging
stability at the measured power levels.

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Annex B. Test Results
B.1 Duty Cycle

Test procedure

Duty cycle is calculated as [(ON Time)/Period].

The Duty cycle within the Burst is multiplied by the Duty cycle over the Burst Period to derive the Duty
Cycle.

The duty cycle of the EUT modulation is measured, and used to provide the duty cycle correction
factor.

Duty Cycle Correction Factor = 10*Log(Duty Cycle)

Where:
Duty Cycle Correction Factor is (dB)
Duty Cycle is (Linear)

The Duty cycle is measured using the FSU67 spectrum analyzer and a standard horn antenna. The
FSU67 covers (20Hz-67GHz) frequency range. Therefore the measurement is performed directly
without a need to an external mixer.

Results tables

Channel 1

ON Time Period Duty Cycle
Description
(ms) (ms) Linear
Duty Cycle
1.991506 2.046635 0.973
Within Burst
Duty Cycle
496.794872 1003.205 0.495
over Burst period
Duty Cycle 0.48187

Duty Cycle Correction (dB) 3.1707

Channel 2

ON Time Period Duty Cycle
Description
(ms) (ms) Linear
Duty Cycle
1.998397 2.067308 0.967
Within Burst
Duty Cycle
496.794872 1000 0.497
over Burst period
Duty Cycle 0.48023

Duty Cycle Correction (dB) 3.1855

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Channel 3

ON Time Period Duty Cycle
Description
(ms) (ms) Linear
Duty Cycle
1.984615 2.060417 0.963
Within Burst
Duty Cycle
496.794872 1003.205 0.495
over Burst period
Duty Cycle 0.4799

Duty Cycle Correction (dB) 3.2149

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Results screenshot

Duty Cycle
Channel 1

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Burst_DutyCycle RBW 10 MHz Delta 3 [Tl ]
* VBW 10 MHz —1.44 dB
Ref —20 dBm Att 5 dB SWT 2 s 1000.000000 ms

ker 1 [Tl ]
~30
~40
—50
1 RM *
CLRWR

~70
—80

~90

~100
~110

Center 60.48 GHz 200 ms/
DutyCycleinBurst RBW 10 MHz Delta 3 [Tl ]
VBW 10 MHz 3.31 dB
Ref —20 dBm Att 5 dB SWT 4.3 ms 2.067308 ms

ker 1 [Tl ]
~30
~40
set
—50
x

~70
—80
~90
~100

~110

Center 60.48 GHz 430 ns/

Date: 22.MAY.2015 18:02:49

Test Report N°15052702.TR01 Rev. 04

Channel 3

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B.2 EIRP & Power Density
Test procedure

The radiated emission level is measured with the aperture probe antenna connected to a power
sensor.

Using the far-field Friis equation:

𝑃𝑅 𝜆 2
= 𝐺𝑇 𝐺𝑅 ( )
𝑃𝑇 4𝜋𝐷
the measured power PR is converted to PT*GT using the same equation in logarithmic domain:

(PT*GT)= PR – GR + Free Space Attenuation (dB)

Where the:
4𝜋𝐷
Free space Attenuation (dB) = 20𝐿𝑜𝑔( )
𝜆

and:

(PT*GT) is (dBm) (P is the transmitted power and GT the emission antenna Gain)
T

D is in (m)
PR is in (dBm)
GR is the small aperture probe antenna Gain in (dBi)
λ is the wavelength in (m)

PT*GT is converted to power density using:

𝑃𝑇 𝐺𝑇
𝑃𝑜𝑤𝑒𝑟 𝐷𝑒𝑛𝑠𝑖𝑡𝑦 =
4𝜋𝐷2

Where:
2
Power Density is in (mW/cm )
PT*GT is in (mW)
D is in (cm)

PT*GT is also converted to EIRP during the ON time of the burst using:
EIRP = (PT*GT) + Duty Cycle Correction Factor

Where:
EIRP is in (dBm)
PT*GT is in (dBm)
Duty Cycle Correction Factor is in (dB)

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Results tables

Channel 1
EUT antenna gain = 15.30dBi

Small Meas
Free Duty
Meas. Aperture Avg Power Cond
Freq Space PT*GT PT*GT Cycle EIRP
Distance Probe Power Density Power
(GHz) Att. (dBm) (mW) Corr. (dBm)
(cm) Gain PR (mW/cm2) (dBm)
(dB) (dB)
GR(dBi) (dBm)
58.32 10 5.37 47.76 -26.65 15.74 37.48 0.02983 3.1707 18.91 3.61
58.32 11 5.37 48.59 -27.44 15.78 37.81 0.02487 3.1707 18.95 3.65
58.32 12 5.37 49.34 -27.80 16.17 41.42 0.02289 3.1707 19.34 4.04
58.32 13 5.37 50.04 -28.37 16.30 42.63 0.02007 3.1707 19.47 4.17
58.32 14 5.37 50.68 -28.79 16.52 44.88 0.01822 3.1707 19.69 4.39
58.32 15 5.37 51.28 -29.14 16.77 47.53 0.01681 3.1707 19.94 4.64
58.32 16 5.37 51.84 -29.70 16.77 47.54 0.01478 3.1707 19.94 4.64
58.32 17 5.37 52.37 -30.13 16.87 48.61 0.01338 3.1707 20.04 4.74
58.32 18 5.37 52.86 -30.65 16.84 48.35 0.01187 3.1707 20.01 4.71
58.32 19 5.37 53.33 -31.13 16.83 48.23 0.01063 3.1707 20.00 4.70
58.32 20 5.37 53.78 -31.49 16.92 49.19 0.00979 3.1707 20.09 4.79

Channel 2
EUT antenna gain = 15.45dBi

Small Meas
Free Duty
Meas. Aperture Avg Power Cond
Freq Space PT*GT PT*GT Cycle EIRP
Distance Probe Power Density Power
(GHz) Att. (dBm) (mW) Corr. (dBm)
(cm) Gain PR (mW/cm2) (dBm)
(dB) (dB)
GR(dBi) (dBm)
60.48 10 5.86 48.07 -26.30 15.91 39.03 0.03106 3.1855 19.10 3.65
60.48 11 5.86 48.90 -26.90 16.14 41.13 0.02705 3.1855 19.33 3.88
60.48 12 5.86 49.66 -27.40 16.40 43.63 0.02411 3.1855 19.58 4.13
60.48 13 5.86 50.35 -27.97 16.52 44.90 0.02114 3.1855 19.71 4.26
60.48 14 5.86 51.00 -28.50 16.64 46.10 0.01872 3.1855 19.82 4.37
60.48 15 5.86 51.60 -28.95 16.79 47.71 0.01687 3.1855 19.97 4.52
60.48 16 5.86 52.16 -29.40 16.90 48.94 0.01521 3.1855 20.08 4.63
60.48 17 5.86 52.68 -29.70 17.12 51.56 0.0142 3.1855 20.31 4.86
60.48 18 5.86 53.18 -30.20 17.12 51.52 0.01265 3.1855 20.30 4.85
60.48 19 5.86 53.65 -30.62 17.17 52.11 0.01149 3.1855 20.35 4.90
60.48 20 5.86 54.09 -31.05 17.18 52.30 0.0104 3.1855 20.37 4.92

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Channel 3
EUT antenna gain = 15.00dBi

Small Meas
Free Duty
Meas. Aperture Avg Power Cond
Freq Space PT*GT PT*GT Cycle EIRP
Distance Probe Power Density Power
(GHz) Att. (dBm) (mW) Corr. (dBm)
(cm) Gain PR (mW/cm2) (dBm)
(dB) (dB)
GR(dBi) (dBm)
62.64 10 7.56 48.38 -25.60 15.22 33.26 0.02646 3.2149 18.43 3.43
62.64 11 7.56 49.21 -26.30 15.35 34.25 0.02253 3.2149 18.56 3.56
62.64 12 7.56 49.96 -26.99 15.41 34.77 0.01922 3.2149 18.63 3.63
62.64 13 7.56 50.66 -27.62 15.48 35.30 0.01662 3.2149 18.69 3.69
62.64 14 7.56 51.30 -28.20 15.54 35.82 0.01454 3.2149 18.76 3.76
62.64 15 7.56 51.90 -28.71 15.63 36.56 0.01293 3.2149 18.85 3.85
62.64 16 7.56 52.46 -29.24 15.66 36.82 0.01145 3.2149 18.88 3.88
62.64 17 7.56 52.99 -29.63 15.80 38.00 0.01046 3.2149 19.01 4.01
62.64 18 7.56 53.48 -30.24 15.68 37.02 0.00909 3.2149 18.90 3.90
62.64 19 7.56 53.95 -30.72 15.67 36.93 0.00814 3.2149 18.89 3.89
62.64 20 7.56 54.40 -31.26 15.58 36.14 0.00719 3.2149 18.79 3.79

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Results graph

Power Density

Power Density (mW/cm^2)
0.100
0.090
Channel 1 Channel 2 Channel 3
0.080
0.070
0.060
0.050
0.040
0.030
0.020
0.010
0.000
10 11 12 13 14 15 16 17 18 19 20
Measurement Distance (cm)
Power Density measured during the tests (i.e. with the ~ 48 % duty cycle measured in B.1)

EIRP

24.00

23.00
EIRP (dBm) EIRP (dBm) EIRP (dBm)
Ch1 Ch2 Ch3
22.00

21.00

20.00

19.00

18.00

17.00
10 11 12 13 14 15 16 17 18 19 20
Measurement Distance (cm)
EIRP normalized for 100% duty cycle (after adding the Duty cycle correction factor measured in B.1)

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Annex C. Aperture Probe Antenna
Characterization
C.1 Description of the Antenna
The measuring antenna is an open-ended waveguide as specified in IEEE Std C95.3-2002 Clause
5.5.1.1.3 Small apertures. The aperture probe antenna consists of a 19 cm straight section of WR15
rectangular waveguide with a standard UG-385/U flange at one end. The aperture dimensions are
2
(1.88 x 3.76 mm ).

C.2 Derivation of characterization equations
Indeed, the ratio between the received power and the transmitted power between a pair of antennas is
expressed in terms of their gains as follow:

𝑃𝑅 4𝜋𝐷 2
𝐺𝑇 𝐺𝑅 = ( )
𝑃𝑇 𝜆

Converting from linear to logarithmic domain yields:

4𝜋𝐷
𝐺𝑇 + 𝐺𝑅 = 𝑃𝑅 − 𝑃𝑇 + 20𝐿𝑜𝑔 ( )
𝜆

Converting from wavelength in meters to frequency in GHz yields:

𝐺𝑇 + 𝐺𝑅 = 𝑃𝑅 − 𝑃𝑇 + 20𝐿𝑜𝑔(𝐷) + 20𝐿𝑜𝑔(𝑓) + 32.44 (1)

Where:

GT is the gain of the transmit antenna (dBi)
GR is the gain of the receive antenna (dBi)
PR is the power received (dBm)
PT is the power transmitted (dBm)
D is the distance between the antennas (m)
f is the frequency (GHz)

The individual far-field gain of each of three different antennas can be determined from three path loss
measurements made under identical far-field conditions using the three different antennas taken in
pairs. Three path loss measurements (PR12 - PT), (PR13 - PT) and (PR23 - PT) are sufficient to
simultaneously solve for three unknowns G1, G2 and G3.

The Equation (1) is applied to each of the three path loss measurement as follows applied

𝐴 = 𝐺1 + 𝐺2 = 𝑃𝑅12 − 𝑃𝑇 + 20𝐿𝑜𝑔(𝐷) + 20𝐿𝑜𝑔(𝑓) + 32.44 (2)

𝐵 = 𝐺1 + 𝐺3 = 𝑃𝑅13 − 𝑃𝑇 + 20𝐿𝑜𝑔(𝐷) + 20𝐿𝑜𝑔(𝑓) + 32.44 (3)

𝐶 = 𝐺2 + 𝐺3 = 𝑃𝑅23 − 𝑃𝑇 + 20𝐿𝑜𝑔(𝐷) + 20𝐿𝑜𝑔(𝑓) + 32.44 (4)

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Where:

A= (G1 + G2) is the sum of the gains of Antennas 1 and 2
B= (G1 + G3) is the sum of the gains of Antennas 1 and 3
C= (G2 + G3) is the sum of the gains of Antennas 2 and 3
PR12 is the power received when measuring Antennas 1 and 2 (dBm)
PR13 is the power received when measuring Antennas 1 and 3 (dBm)
PR23 is the power received when measuring Antennas 2 and 3 (dBm)
PT is the transmitted power (dBm)
D is the distance between the antennas (m)
f is the frequency (GHz)

The gain of each individual antenna is calculated as follows:

𝐺1 = 0.5 (𝐴 + 𝐵 − 𝐶) (5)
𝐺2 = 0.5 (𝐴 + 𝐶 − 𝐵) (6)
𝐺3 = 0.5 (𝐵 + 𝐶 − 𝐴) (7)

Where:

G1 is the gain of Antenna 1 (dBi)
G2 is the gain of Antenna 2 (dBi)
G3 is the gain of Antenna 3 (dBi)
A is the result of applying Equation (2)
B is the result of applying Equation (3)
C is the result of applying Equation (4)

C.3 Characterization Procedure

1. Allow the signal source, power sensor and power meter to warm up as specified by the
manufacturer of the instruments.

2. Adjust the instruments to the applicable frequency. Connect the power sensor to the output of the
source. Measure and record Power Transmitted.

3. Connect the first pair of antennas to their respective source (Tx antenna) and power sensor (Rx
antenna). Place the antennas at the selected far-field separation distance in a bore-sight configuration
using a laser level to align the antennas. Measure and record Power Received.

4. Repeat step 3 for each pair of antennas.

5. Calculate the antenna gains by applying Equations (2) through (7).

FO-014: Test Report 18 of 21
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Test Report N°15052702.TR01 Rev. 04

C.4 Characterization Results and Validation
C.4.1 Far-Field Distance
The gain reduction (relative to the far-field gain G∞) of an antenna is estimated as a function of
normalized distance.
The normalized distance is given in terms of n = dλ/a2 where d is distance, λ is wavelength and a is
the largest aperture dimension. The far-field gain holds for distances greater than about (8a2)/λ (n >
8).

Note that for the verification we use three aperture antennas, the far field distance is therefore
calculated using the largest aperture dimension among the three antennas (in our case it is the
antenna 1) and a= 5mm.

The minimum far field distance is calculated for each channel as follow:

Frequency Wavelength Largest aperture 2 Minimum distance
Ratio (a /λ )
(GHz) λ (m) dimension a (m) d (cm)
58.32 0.005144033 0.005 0.00486 3.888
60.48 0.004960317 0.005 0.00504 4.032
62.64 0.004789272 0.005 0.00522 4.176

We decide therefore to do the characterization at 15 cm.

C.4.2 Probe Gain
The probe under verification is noted Antenna 3 with Gain G3. The antennas 1 and 2 are used to
perform the characterization. The verification procedure (see § 12.3) is applied as follow:
st
1 Path Loss measurement  In Tx : Antenna 1 / In Rx : Antenna 2

PT PR12
Channel D (m) f (GHz) G1+G2 (dBi)
(dBm) (dBm)
1 5.01 -30.53 0.15 58.32 15.74
2 7.34 -29.41 0.15 60.48 14.84
3 7.04 -28.28 0.15 62.64 16.58
nd
2 Path Loss measurement  In Tx : Antenna 2 / In Rx : Antenna 3

PT PR23
Channel D (m) f (GHz) G2+G3 (dBi)
(dBm) (dBm)
1 5.01 -35.3 0.15 58.32 10.97
2 7.34 -32.93 0.15 60.48 11.32
3 7.04 -30.66 0.15 62.64 14.199

rd
3 Path Loss measurement  In Tx : Antenna 1 / In Rx : Antenna 3

PT PR13
Channel D (m) f (GHz) G1+G3 (dBi)
(dBm) (dBm)
1 5.01 -30.76 0.15 58.32 15.51
2 7.34 -29.01 0.15 60.48 15.24
3 7.04 -27.35 0.15 62.64 17.51

FO-014: Test Report 19 of 21
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Test Report N°15052702.TR01 Rev. 04

The measured gains are deduced and showed as follows:

Channel 1 Channel 2 Channel 3
Antenna
Gain (dBi) Gain (dBi) Gain (dBi)
Aperture Antenna 1 10.14 9.38 9.94
Aperture Antenna 2 5.60 5.46 6.63
Open Ended Waveguide Probe Antenna 5.37 5.86 7.56

C.4.3 Validation
The measured gain of the original probe antenna is compared to the realized gain from a theoretical
model of common open-ended waveguide apertures with a two-to-one aspect ratio, i.e., a /b = 2,
provided by IEEE Std C95.3 Clause 5.5.1.1.3 equation (4)
Delta to
Measured
Frequency Dimension a Theoretical Gain (dBi) Theoretical
Gain
Channel (GHz) (m) 10 log(21.6 ∙ 𝑓[𝐺𝐻𝑧] ∙ 𝑎) Gain
(dBi)
(dB)
1 58.32 0.00376 6.75 5.37 1.38
2 60.48 0.00376 6.91 5.86 1.05
3 62.64 0.00376 7.06 7.56 0.50

FO-014: Test Report 20 of 21
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Test Report N°15052702.TR01 Rev. 04

Annex D. Photographs
Test Setup

FO-014: Test Report 21 of 21
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Document Created: 2015-08-31 10:10:48
Document Modified: 2015-08-31 10:10:48

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