Supplemental Emissions Test Report

FCC ID: O2Z-BT2

Test Report

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FCCID_139993

EXHIBIT O – Supplemental Emissions Test Report

FCC ID O2Z-BT2

A. Bettner
2/15/01
Modular Approval Emissions Tests
Taken at NW EMC
January, 2001

The purpose of these tests is to conduct similar tests to those requested by the FCC for Intel’s modular approval
grant (OZ-BT1, November 2000) on a similar Bluetooth module. As in the previous request by the FCC for
emissions data (Refer to Exhibit OO of grant OZ-BT1), a subset consisting of three sets of data were taken (see
Appendix A for a description of the original complete set of tests):

1) Measurement of emissions from the highest gain antenna connected directly to the module (with
minimal transmission line (highest output power))

2) Measurement of emissions from the module connected to a straight microstrip (resonant length)
between the module and the antenna.

3) Measurement of emissions from the same configuration as 2), only with a 50 ohm shielded load in
place of the antenna.

4) Measurement of emissions from the module connected to a meandered microstrip (resonant length)
plus coax (resonant length) connected to the highest gain antenna

Test 1) establishes the “worst case” emissions test since the highest gain antenna is being used and the length of
transmission line (loss) is minimized.

Test 2) demonstrates whether the spurious emissions are increased by the addition of resonant section of open
microstrip transmission line.

Test 3) (with 50 ohm shielded termination) demonstrates whether the transmission line itself is radiating.

Test 4) is a “worst case” emissions test based on a combination of both an open meandered line of resonant
length and a piece of coax of resonant length.

Resonant lengths of open transmission line and cable were computed using the equations found in Appendix B ,
attached.

Test results:

Test results for each of the configurations described above may be found in Appendix C. No detectable
emissions from the radio were found at any frequencies below 2400 MHz or above 7500 MHz. Configuration
1) produced the highest level of radiated emissions: at 7320 MHz the peak level was 2.5dB below the 74
dBuV/m peak limit, the highest average level was also at 7320 MHz with a margin of 6.9 dB below the 54
dBuV/m average limit. Configuration 1) is the worst case condition because it transmits the highest power
(shortest coax, highest gain antenna). No other configuration, including an open transmission line produced a
condition exceeding these levels.

While scanning, emissions from the EUT were maximized by rotating the EUT, adjusting the measurement
antenna height and polarization, and manipulating the EUT and transmission line/antenna configuration in 3
orthogonal planes (per ANSI C63.4:1992). A preamp and high pass filter were use for this test in order to
provide sufficient measurement sensitivity.

$A. Bettner 2/15/01 Appendix A. Original Proposed Tests (From previous MA filing OZ2-BT1) 1. To demonstrate that the microstrip transmission line radiates only minimally, Intel will perform and record a scan test on the module with an antenna connected and with the antenna disconnected. When the antenna is disconnected, the transmissio n line will be terminated with a shielded 50 ohm SMA termination. The length of microstrip transmission line is to be an integer fraction of the center frequency, 2440 MHz. Any one of the four antennas to be used with the module may be used for this test. 2. To demonstrate that a coaxial cable connected to the microstrip transmission line radiates only minimally, Intel will perform and record a scan test on the module with and without the cable connected to the transmission line. Any one of the four antennas can be used with the module. The length of the coaxial cable is to be an integer fraction of the center frequency, 2440 MHz. 3. For the following tests, the same length of microstrip transmission line as in (1) (i.e. an integer fraction of the center frequency, 2440 MHz) shall be used, connected on one end to the transmission line and on the other end to one of the antennas to be used with the module. The following tests shall be performed and recorded: (a) a minimum dimension (W and H) 50 ohm transmission line will be tested in a straight line and a meandered line (two 45 degree angle turns) configuration; Intel estimates that the minimum dimension line trace will be approximately 7 mil by 4.4 mil; (b) a maximum dimension (W and H) 50 ohm transmission line will be tested in a straight line and a meandered line (at least two 45 degree angle turns) configuration; Intel estimates that the maximum dimension line trace will be approximately 115 mil by 63 mil. The same antenna as used in Paragraph 2 shall be used with the foregoing tests. 4. Intel will perform a test with the same antenna used in Paragraph 3, connected as close to the module as may be implemented by an OEM customer. 5. Using the test configuration which produces the "worse case" test results from Paragraphs 3 and 4 above, Intel will test the three other types of antennas which will be marketed with the module in the worse case configuration. No other test with the three antennas will be required.$

A. Bettner
2/15/01
Appendix B
Transmission Line Calculations

Coax:

A section of coaxial cable producing common mode emissions will have an electrical length of simply:

L(meters) = c/f

Where c = 3 x 108 meters
And f= freq (Hz)

For this case, we want the line to be 3 wavelengths long at 2440 MHz, or one wavelength long at 813 MHz.

L = 3 x 10 8 / 813 x 10 6 = .363 meters = 14.3 inches (air)

Microstrip:

For the wide microstrip line the following parameters were used:

H (board thickness) = 0.062 inches
Er (Dielectric constant) = 4.5 (for FR-4 material)
F0 (center frequency) = 2440 MHz

For a 50 ohm line:

W (line width) = 0.115 inches
L (1080 degrees, for resonance at 813 MHz) = 7.822 inches

For the narrow (6 mil), the following parameters were used:

Er (Dielectric constant) = 4.5 (for FR-4 material)
F0 (center frequency) = 2440 MHz

For a 50 ohm line:

H (board height) = 4 mil
L(1080 degrees, for resonance at 813 MHz) = 7.95 inches

A. Bettner
2/15/01
Appendix C
Emissions Data

Configurations

1) Measurement of emissions from the highest gain antenna connected directly to the module (with
minimal transmission line (highest output power))

2) Measurement of emissions from the module connected to a straight microstrip (resonant length)
between the module and the antenna.

3) Measurement of emissions from the same configuration as 2), only with a 50 ohm shielded load in
place of the antenna.

4) Measurement of emissions from the module connected to a meandered microstrip (resonant length)
plus coax (resonant length) connected to the highest gain antenna

Minimum Margins (dB)
Detector Config 1. Config 2. Config 3. Config 4.
Average -6.9 -11.1 -10.4 -8.7
Peak -2.5 -13.8 -13.6 -11.9

Complete test results are found on the following pages.

Rev 3.5
Northwest EMC, Inc., Radiated and Conducted Emissions Data Sheets 01/11/01

EUT: Serial Number: Job Number: Date:
Intel(R) Personal Wireless Module New module #2 1/15/01 INSC0011 01/16/01
Manufacturer: Test Engineer: Job Site:
Intel Corporation Greg Kiemel EV01
Customer Reference Number: Software: Power:

Comments:
No hop, antenna 'B'
Temperature (°C): % Humidity:
20 34

FCC 15.209 Average Radiated Emissions (3 meter limit)

80.0 THIS FINAL DATA REPRESENTS MAXIMIZED (CABLES, ANTENNA & TURNTABLE) MEASUREMENTS.

70.0

60.0
dBuV/meter

50.0

40.0

30.0

20.0

10.0

0.0
2484 3484 4484 5484 6484 7484

Frequency (MHz)
Meter Antenna Antenna Preamp Table Antenna Adjusted Spec.
Frequency Reading Detector Factor Polarity Gain Cable Loss Azimuth Height Level Limit Margin Comment
(MHz) (dBuV) (dB/m) (dB) (dB) (degrees) (meters) (dBuV/m) (dBuV/m) (dB)
2483.500 40.4 AV 27.9 VHRN 33.9 2.6 185.0 1.3 37.0 54.0 -17.1 High Xmit freq.
2483.500 40.0 AV 27.9 HHRN 33.9 2.6 245.0 2.2 36.6 54.0 -17.5 High Xmit freq.
4803.787 39.4 AV 32.8 VHRN 34.3 4.4 117.0 2.8 42.3 54.0 -11.7 Low Xmit freq.
4803.805 37.7 AV 32.8 HHRN 34.3 4.4 143.0 2.8 40.6 54.0 -13.4 Low Xmit freq.
4880.000 34.9 AV 32.9 VHRN 34.3 4.4 120.0 2.8 37.9 54.0 -16.1 Mid Xmit freq.
4880.000 33.9 AV 32.9 HHRN 34.3 4.4 229.0 2.1 36.9 54.0 -17.1 Mid Xmit freq.
7320.060 36.2 AV 36.8 VHRN 31.8 5.9 245.0 2.0 47.1 54.0 -6.9 Mid Xmit freq.
7320.060 33.9 AV 36.8 HHRN 31.8 5.9 241.0 2.1 44.8 54.0 -9.2 Mid Xmit freq.
7440.000 33.3 AV 37.3 HHRN 31.4 5.9 295.0 2.0 45.1 54.0 -8.9 High Xmit freq.
7440.000 34.0 AV 37.3 VHRN 31.4 5.9 247.0 2.3 45.8 54.0 -8.3 High Xmit freq.

Document Created: 2001-03-12 11:24:23
Document Modified: 2001-03-12 11:24:23