Description of experiment and additional exhibits

0005-EX-ML-2016 Text Documents

General Motors Research Corporation

2016-01-05ELS_171025

EXHIBIT 1
Description of General Motors Research Corporation Operations

The General Motors (GM) Validation Center is a GM facility in Warren, Michigan. The
campus is home to 16,000 GM engineers, designers, and technicians, and has been the center of
the company’s engineering efforts for more than 50 years. GPS navigational systems and
infotainment systems are developed and tested in this facility. Bringing GPS signals inside
additional testing rooms at GM’s Validation Center will greatly enhance GM’s ability to more
efficiently and effectively test, manage, and develop these systems.

General Motors Research Corporation (“GMRC”), a wholly owned indirect subsidiary of GM,
requests a modification of its experimental license WE2XUD to re-radiate GPS signals into additional
testing rooms at the GM Validation Center. The proposed operations are identical to GMRC’s
existing licensed operations pursuant to WE2XUD, except they will be located in the AEC building at
the GM Validation Center. See Exhibit 2, Additional Testing Locations.

The infotainment system testing at the AEC building occurs indoors, and therefore the roof of
the facility blocks GPS signals from reaching the testing rooms. GMRC requests authority to
operate three additional GPS Networking Inc. GPS re-radiation kits (Model No. HNRRKIT-N/5/110).
See Exhibit 3, GPS Re-Radiator Technical Specifications. The GPS signals received and re-
transmitted into the AEC building will allow GMRC and its affiliates to complete the necessary testing
to certify that the infotainment systems meet the applicable operating specifications. The emission
calculations included in Exhibit 3 demonstrate that the GPS re-radiation kits comply with the
Commission’s emission limits for GPS re-radiators.

FCC approval is requested in advance of February 1, 2016, so that GMRC and its affiliates
may conduct infotainment system testing in the proposed locations.

Objectives

GMRC seeks to accomplish the following objectives:
1. Transmission of GPS signals inside the AEC building.
2. Conduct tests to certify that GM’s infotainment systems satisfy the applicable operating
specifications.
3. Test equipment implementation and troubleshoot problems in a controlled environment.

Contribution to Radio Art

GMRC continues to improve GPS navigation and infotainment systems that are currently
available in GM vehicles. This project is necessary to validate the effectiveness of the improved
GPS navigation and infotainment systems. Improved GPS navigation and infotainment systems
provide a number of benefits including, for example, more precise vehicle location information, which
saves time and helps prevent the loss of life in emergency situations.

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EXHIBIT 4
8.3.28 Use of Fixed Devices that Re-Radiate Signals Received from the Global Positioning
System

Except as otherwise authorized under Part 7.14, federal agencies and departments may, under the
following conditions, operate fixed devices that re-radiate signals received from the Global
Positioning System (GPS).
1. Individual authorization is for indoor use only, and is required for each device at a specific site.
YES

2. Applications for frequency assignment should be applied for as an XT station class with a note
indicating the device is to be used as an "Experimental RNSS Test Equipment for the purpose of
testing GPS receivers" and describing how the device will be used.
YES

3. Approved applications for frequency assignment will be entered in the GMF.
YES

4. The maximum length of the assignment will be two years, with possible renewal.
YES

5. The area of potential interference to GPS reception. (e.g., military or contractor facility) has to be
under the control of the user.
YES

6. The maximum equivalent isotropically radiated power (EIRP) must be such that the calculated
emissions are no greater than -140 dBm/24 MHz as received by an isotropic antenna at a distance
of 100 feet (30 meters) from the building where the test is being conducted. The calculations
showing compliance with this requirement must be provided with the application for frequency
assignment and should be based on free space propagation with no allowance for additional
attenuation (e.g., building attenuation.)
SEE ATTACHED EMISSION CALCULATION

7. GPS users in the area of potential interference to GPS reception must be notiﬁed that GPS
information may be impacted for periods of time.
YES

8. The use is limited to activity for the purpose of testing RNSS equipment/systems.
YES

9. A "Stop Buzzer" point of contact for the authorized device must be identiﬁed and available at all
times during GPS remediation operation of the device under any condition.

Primary - Tom Spoto -- Engineer 586-419-5982
thomas.a.spoto@gm.com

Backup – Stephen L. Snyder – Engineer 586-863-7127
Stephen.l.snyder@gm.com

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Emission Calculation

L1 Calculation
Label Parameter Value Units Notes / Formula
A Transmit ERP 24 pW

B Frequency 1575.42 MHz L1 center frequency
C Distance 100 feet Required distance
D Distance 30.5 meters = C / 3.2808 feet/meter
= 20 * log(B) + 20 * log(D) -
E Free Space Path Loss 66.1 dB
27.55

F Transmit ERP -76.2 dBm = 10 * log(A / 1,000,000,000)
G Transmit EIRP -74.0 dBm = F + 2.15

H Received Power -140.1 dBm =G–E

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Document Created: 2016-01-05 16:49:23
Document Modified: 2016-01-05 16:49:23

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