Attachment LightSquared - USGPS

This document pretains to SAT-MOD-20101118-00239 for Modification on a Satellite Space Stations filing.

IBFS_SATMOD2010111800239_862413

                                                                                     ORIGINAL
  & fgiartts
L            | LERMAN

         |                               EX PARTE OR LATE FILED
WASHINGTON, DC
                                                                                      STEPHEN D. BARUCH
                                                                                          202.416.6782
                                                                                 SBARUCH@LERMANSENTER.COM



                                      January 20, 2011


                                                                                   FILED/ACCEPTED
By Hand Delivery
Matlene H. Dortch                                                                       JAN 2 0 2911
Secretary       2o           2o                                                                 hax
                                                                                 Federal Communications Commission
Federal Communications Commission                                                      Office of the Secretary
445 Twelfth Street, S.W.
Washington, D.C. 20554

       Re:     Notice of Ex Parte Presentation in LightSquared Subsidiary LLC
               Application for Modification of Authority for Ancillary Terrestrial
               Component, File No. SAT—MOD—20101118—00239

Dear Ms. Dortch:


       On January 19, 2011, representatives of the United States GPS Industry Council
and several member companies held a teleconference with officials from the
Commission‘s Office of Engineering and Technology, International Bureau, Public
Safety and Homeland Security Bureau, and Wireless Telecommunications Bureau to
discuss the results of empirical experimentation conducted by Garmin International
("Garmin") to assess the impact on GPS receivers operating in the 1559—16 10 MHz band
of fixed, high—power terrestrial broadband transmitters of the new, non—ancillary type
LightSquared Subsidiary LLC ("LightSquared") first proposed in its above—referenced
November 2010 application. The LightSquared application proceeding has been
designated to have permit—but—disclose status for purposes of the Commission‘s ex parte
rules.

       The participants (listed on Appendix 1 to this letter) discussed in detail the
methodology, parameters, and findings presented in the Garmin report, entitled
Experimental Evidence of Wide Area GPS Jamming That Will Result from
LightSquared‘s Proposal to Convert Portions of L Band 1 to High Power Terrestrial
Broadband, that is included as Appendix 2 to this letter.




                     2000 K STREET NW, SUITE 600 | WASHINGTON, DC 20006—1809
                    TEL 202.429.8970 | FAX 202.293.7783 | WWW.LERMANSENTER.COM


L      |     Marlene H. Dortch
    g l      January 20, 2011
.            Page 2


           By this letter, and in accordance with Section 1.1206 of the Commission‘s Rules,
    47 C.F.R. § 1.1206, two copies this letter and its Appendices are provided for inclusion in
    the Commission‘s files.

           Please direct any questions to me.

                                          Respectfully submitted,




                                          Stephen/D. Baruch
                                          Counsel for the United States GPS Industry Council

    Enclosures


    ce: (w/Enclosures): List of Persons in Appendix 1 (by e—mail)


                                                                    APPENDIX 1

     LIST OF PARTICIPANTS IN JANUARY 19, 2011 TELECONFERENCE

FCC PARTICIPANTS:                           U.S. GPS Industry Council Participants

Office of Engineering and Technology:   U.S. GPS Industry Council:

Julius Knapp, Chief                     F. Michael Swiek, Executive Director
Ronald Repasi                           A.J. von Dierendonck
Michael Ha                              Stephen D. Baruch (Lerman Senter PLLC)
Mark Settle
Robert Weller                           Garmin International:

International Bureau                    Andrew Etkind
                                        Scott Burgett
Robert Nelson                           Bronson Hokuf
Sankar Persaud                          Doug Kealy
                                        Brian Poindexter
Public Safety and Homeland Security     Van Ruggles
Bureau:                                 Micheal C. Simmons
                                        M. Anne Swanson (Dow Lohnes PLLC)
Pat Amodio
                                        Trimble Navigation, Ltd.:
Wireless Telecommunications Bureau:
                                        Ann Ciganer
Paul Murray                             Bruce Peetz
Tom Peters                              Russell Fox (Mintz, Levin, Cohn, Ferris, Glovsky
                                        and Popeo, P.C.)


APPENDIX 2


      Experimental Evidence of Wide Area GPS Jamming That Will Result from
       LightSquared‘s Proposal to Convert Portions of L Band 1 to High Power
                                       Terrestrial Broadband

                                             January 16, 2011
                                      Scott Burgett, Bronson Hokuf
                                   Garmin International, Olathe, Kansas

Executive Summary



On November 18, 2010 LightSquared Subsidiary LLC filed an application requesting modification of its
authority for Ancillary Terrestrial Component (FCC File No. SAT—MOD—20101118—00239) of L Band 1 MSS
(Mobile Satellite Service). This application proposes to fundamentally change the usage of the L Band 1
spectrum (1525 MHz— 1559 MHz) from MSS (very low power, space to earth signals) to fixed, high
power, terrestrial broadband service. The L Band 1 is adjacent to the GPS band (1559 MHz — 1610 MHz)
where the GPS and other satellite based radio navigation systems operate.

If this modification is approved, widespread, severe GPS jamming will occur. in careful, experimental
testing at Garmin using the technical details (power, frequency, modulation bandwidth) of the proposed
LightSquared system, two common state—of—the—art Garmin GPS receivers experienced significant
jamming within a radius of several miles from a simulated LightSquared transmitter.


The nlivi 265W, a very common portable consumer automotive navigation device, began to be jammed
at a power level that represents a distance of 3.6 miles (5.8 kilometers) from the transmitter. The niivi
265W lost a fix at a distance of 0.66 miles (1.1 kilometers}) from the transmitter.


A GNS 430W, a common FAA certified General Aviation receiver that supports the FAA‘s NextGen RNAV
and RNP operations, began to be jammed at a distance of 13.8 miles (22.1 kilometers) from the
LightSquared transmitter. Total loss of fix occurred at a distance of 5.6 miles (9.0 kilometers) from the
LightSquared transmitter. This GPS receiver is certified for LPV (Localizer Performance with Vertical
guidance) approach operations to 200 feet decision height, yet will be completely jammed by
LightSquared transmitters over 5.6 miles (9.0 kilometers) away. Further, due to the special FAA
requirements that this receiver is designed to meet, it takes on the order of 90 seconds to regain a fix
once lost.


Background


As discussed in the Executive Summary, LightSquared wants to fundamentally change the nature of L
band 1 (1525 MHz— 1559 MHz) from a mobile, space to earth band containing very weak signals to a
very noisy terrestrial broadband band full of extremely powerful signals. This will have a severe impact
on the adjacent GPS band (1559 MHz — 1610 MHz) where GPS and other satellite navigation and


augmentation systems operate (Glonass, Galileo, WAAS, etc).



LightSquared‘s published plans (ref LightSquared Letter to Marlene Dortch, November 18, 2010) entail
the installation of up to 40,000 high power transmitters. These transmitters are authorized for up to 42
dBW (over 15,000 watts). The operation of so many high powered transmitters so close in frequency
to the GPS operating frequency (1575.42 MHz) will create a disastrous interference problem for GPS
receiver operation to the point where GPS receivers will cease to operate (complete loss of fix} when
in the vicinity of these transmitters.


Garmin products represent over 90% of the installed navigation equipment in the General Aviation
segment in the United States. Garmin also represents over 50% of the portable consumer automotive
and handheld GPS devices sold in the United States. When faced with this potentially catastrophic
interference threat, Garmin set out to quantify the jamming threat by carefully simulating the jamming
scenario in the lab using high fidelity simulation equipment. Garmin tested two of our most popular
devices. From the consumer automotive segment, testing was performed using a nlvi 265 W, which is a
popular member of a best—selling family of consumer automotive navigation devices. From the aviation
segment, testing was performed using a GNS 430W, a receiver designed to meet the FAA TSO—C146a
minimum performance specifications and which presently supports FAA‘s NextGen RNAV and RNP
operations and is expected to be approved as a position source for FAA‘s NextGen ADS—B Out mandate.


Due to the accelerated schedule with which the FCC is processing LightSquared‘s request for waiver,
only these two devices were tested in the interest of time. These devices are very representative of the
installed user base of Garmin products in the United States.


Experimental Setup


The goal of these experiments was to use Garmin‘s engineering test lab to faithfully replicate the real—
world scenario of LightSquared‘s proposed transmissions in the MSS band adjacent to GPS signals in the
RNSS band. In general, care was taken to err in LightSquared‘s favor whenever assumptions were made
about its transmissions. For example, Order and Authorization (SAT—MOD—20090429—00047, et. al.)
released March 26, 2010 authorizes transmissions of 42 dBW EIRP (15.85 kW) with power allowed all
the way to the band edge of 1559 MHz (paragraph 46); however, this test setup was based on
LightSquared‘s verbal guidance (conference call between LightSquared and the USGPSIC (US GPS
Industry Council), December 17", 2010) that they would not transmit in excess of 32 dBW EIRP at 1555
MHz. Furthermore, the simulated GPS scenario used was comprised of strong signals and a stationary
DUT (device under test) (no dynamics, fading, etc.).


LightSquared Transmitter Setup


Table 1 shows the constraints that were used to replicate LightSquared‘s transmissions in the MSS band.
These were based on information that LightSquared provided to the USGPSIC on December 17, 2010.
Once again, it is important to note that the upper band edge used for this experiment is only 1555 MHz,
not 1559 MHz, which is the upper band edge of L Band 1 and would represent the worst case
interference scenario.


                               TX Power (P;x)                62 dBm
                               Center Frequency          1552.5 MHz
                               Modulation                     QaPSK
                               Bandwidth                       5 MHz
                               Transmit Antenna
                                  .                            0 dBi
                               Gain (Gaf)

                            Table 1: LightSquared Transmitter Specifications


in order to calculate the power incident upon one of the millions of deployed GPS navigation devices in
the field at a given distance from the transmit tower, standard link budget and path loss equations for
free space propagation were used. The power incident on the DUT (Poyy) is equal to the transmit power
{P1x) plus the transmit antenna gain (Ga;) plus the path loss (Gp,, a negative quantity).


                                      Pour = Prx + Gar + Gpr
Likewise, the free space path loss with respect to distance d and wavelength A (in meters) is given by:


                                                              4Anrd
                                       GPL =—— '—ZOLOg (T)



The resultant Poyr is shown with respect to distance in Figure 1.


                            Poy; Versus Distance from Transmitter
                     0.0                  ]    |

                    —10.0


                &
                ~ —20.0 \'\
                '% —30.0
                                          ~C   f           =a
                                                                              |_|
                                                                              i—I

                & —40.0                                         [——           _
                    —50.0                            [                            ~~   &__
                    —60.0                          L._L1                           4
                            100                            1000                         10000

                                              Distance from Transmitter (m)


                                  Figure 1: Poyy Versus Distance from Transmitter


Experimental Setup in the Anechoic Chamber


As stated earlier, the goal of these tests was to emulate LightSquared‘s transmitter in a controlled
laboratory environment. Consequently, the test setup was designed to allow the DUT to experience the
same power levels seen in Figure 1 while simultaneously receiving ideal simulated GPS signals. An RF
shielded room / anechoic chamber was used to create a test environment free from reflections and
outside interference. In addition, calibrated antennas and state of the art test equipment were used to
create the best possible test with the information available to date.


LightSquared Transmitter Simulation Setup


LightSquared‘s signal was simulated according to the parameters described above in Table 1 using a
Rhode and Schwartz SMIQ—O3S signal generator with digital modulation. This signal was then amplified
with an Amplifier Research linear 5SW amplifier (Model #551G4) to achieve the signal strengths needed
to run the test. The output of the amplifier was padded by 10 dB and then run through a notch filter
centered at 1575.42 MHz to reject any in—band spurious emissions from the RF signal generator. A
detailed list of test equipment is available upon request. An Agilent N9020A spectrum analyzer was
used to measure the output power (P;7y) of the LightSquared Transmitter Simulator as illustrated in
Figure 2.


                         Light Squared Transmitter Simulator                                                             Agilent N9020A
        R&S SMIQ—035            Amplifier Research             100B       GPS Notch                 cable loss = 0.5dB   Signal Analyzer
                                                               Pad        Filter




                                                     Figure 2: Transmitter Simulator Setup



Next, the output of the transmitter simulator was connected to a vertically polarized transmitting
antenna located inside an RF anechoic chamber at exactly 3 meters from the DUT, as illustrated in Figure
3.

                                                                               RF AnechoicChamber




                                                       ‘““    &       d > 3 meters
                             \/%’*&"&Li‘(
      GPS Simulator




                                                                                             d= 3 meters
 Light Squared Transmitter
          Simulator
           (Prd




                                                            Figure 3: RF Anechoic Chamber Test Setup


Hence, the power incident upon the DUT (Poy3) was controlled according to the following equation.


                                       Pour = Prx + GcaBir + Gar + Gp1(Bm)

The free space path loss at 3 meters follows the path loss equation stated earlier such that Gp; (3m) =
—45.8dB. Furthermore the Cable Loss (Gcasie) was measured with a Network Analyzer as Grag;s =
—2.56dB at 1552.5 MHz. Finally, the vertically polarized test antenna had a gain of G4; = 6.8dBi at
1550 MHz. These numbers were used to calculate the power incident upon the DUT and then a
simulated path 10SS (Gpi—simulatea) was derived based on a LightSquared‘s stated transmit power of 62dBm
(32dBW) and assumed antenna gain of 0OdBi. This simulated path loss was then used to calculate the
simulated distance from the LightSquared transmitter by the following equation.


                                                              A       _(w)
                                                       d = — 10
                                                             41t


The test results shown henceforth throughout this document are based upon this setup. The actual
jamming levels were measured during the experiment and then used to calculate the apparent distance
from LightSquared‘s transmitter.


GPS simulation setup


The GPS signals were simulated by a Spirent GSS 6560 GPS Simulator. A stationary scenario at location
N39.0000 and W95.0000 was used. The GPS constellation simulated contained 31 GPS satellites, which
is the number of GPS satellites currently active. The time was set to the current wall clock time and was
allowed to run freely over the duration of the test to facilitate the acquisition of GPS signals by the
devices under test.


An external LNA (Mini—Circuits PN ZHL—1217HLN) was used in series with a right—hand circularly polarized
(RHCP) conical antenna in an RF anechoic chamber. The output signal of the Spirent was adjusted so that
each DUT reported a signal strength of approximately 40 dB—Hz C/No.


This scenario is considered to be rather benign in that there is no acceleration or signal obscuration
being simulated. A reported signal strength of 40 dB—Hz is considered to be a strong signal.


Units Tested


Due to the accelerated nature with which the FCC is considering LightSquared‘s request for modification
of its ATC authorization, there was not an abundance of time with which to test. In the interest of time,
Garmin selected two common units, a niivi 265 W and a GNS 430W—— one from the Consumer
Automotive business segment and one from the Certified Aviation segment.


The nivi 265W is representative of Garmin‘s family of PNDs (Portable Navigation Devices). Tens of
millions of devices similar to the nlvi 265W have been sold in the past few years in North America. It is
also representative of the technology used by other manufactures of PND‘s, SmartPhones, and other
portable GPS units. It is designed using a state of the art antenna, preselect filter, LNA, post—LNA filter
and GPS demodulator. It is a high sensitivity, multi—channel design.


The GNS 430W is one of a number of FAA—certified navigation devices produced by Garmin that utilize a
common GPS/SBAS receiver designed to meet the FAA TSO—C146a and TSO—C145a minimum
performance specifications documented in RTCA DO—229C. As of December 31, 2010, Garmin has
produced and shipped 57,812 FAA—certified products that utilize this GPS/SBAS receiver design. These
products are installed in an estimated 43,321 aircraft worldwide. Garmin estimates that 70% of these
products and aircraft are in the United States.


Test Results


Ndvi 265 W Jamming


Table 2 describes the effect of jamming on the nlvi 265W. "Jamming is Detected" refers to the point at
which the receiver experiences 1 dB of de—sensitization. "Loss of Fix in the Urban Canyon" refers to the
point at which the receiver experiences 10 dB of de—sensitization. In Garmin‘s judgment, this much loss
of signal in a challenging urban canyon environment would typically result in a loss of GPS service. "Loss
of Fix in the Open Sky" refers to the point at which the GPS receiver lost its fix completely.


                                                                        Distance
                                   Effect
                 Jamming is detected                            3.57 miles (5756 meters )

                  Loss of Service in the Urban Canyon           1.79 miles (2884 meters )

                  Loss of Fix in the Open Sky                   0.66 miles (1059 meters)

                                          Table 2: nuvi 265W Results



GNS 430W Jamming


Table 3 describes the effect of jamming on the GNS 430W. "Jamming is Detected" refers to the point at
which the receiver experiences 1 dB of de—sensitization. "10 dB Loss of Sensitivity" refers to the point at
which the receiver experiences 10 dB of de—sensitization. "Loss of Fix in the Open Sky" refers to the
point at which the GPS receiver lost its fix completely.


                                                                       Distance
                                  Effect
                Jamming is detected                           13.76 miles (22137 meters )

                10 dB Loss of Sensitivity                      9.85 miles (15853 meters)

                Loss of Fix in Open Sky                         5.60 miles (9018 meters )

                                          Table 3: GNS 430W Results


Conclusion


As shown by the Garmin testing described in this document, the proposed LightSquared plan to add
40,000 high—powered transmitters in the band adjacent to GPS will result in widespread, severe GPS
jamming. This will deny GPS service over vast areas of the United States.



Document Created: 2019-04-21 18:57:13
Document Modified: 2019-04-21 18:57:13

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