Exhibit 1

0045-EX-ML-2002 Text Documents

Space Data Corporation

2002-08-28ELS_57989

                                                                          Space Data Corporation
                                                          Modification of Experimental License
                                                                                FCC Form 405
                                                                                     Exhibit 1
                                                                                  August 27, 2002
                                                                                      Page 1 of 3

                        Exhibit 1: Modification of Experimental License

        Space Data Corporation ("Space Data"), pursuant to Section 5.59(b) of the
Commission‘s rules,‘ requests a modification to its experimental license (call sign:
WC2XVM) to include access to the 895.5—895.7 MHz frequencies in order to test a single
off—the—shelf Global System for Mobile Communications ("GSM") mobile handset with
Space Data‘s system. The tests would be confined to various locations within the state of
Arizona, each of which will be located at least 90 miles from the only stationary site
licensed in Arizona to operate within the 895.5—895.7 MHz band (specifically, at
895.4055—895.5973 MHz).

       Space Data‘s experimental license authorizes Space Data to perform experimental
operations of its balloon—based communications system using GSM and other
transmission protocols and channel bandwidths of up to 200 kHz over various
Narrowband Personal Communications Services ("NPCS") frequencies. Space Data now
seeks to test the ability ofits system to carry standard GSM—based wireless calls, using a
GSM handset to communicate with its system‘s airborne balloon—based repeaters.

        Because standard GSM handsets use a 200 kHz channel bandwidth and a 45 MHz
offset between the send and receive channels, Space Data requires access to additional
frequencies. Accordingly, Space Data requests FCC authorization to undertake the GSM
experiment using the 895.5—895.7 MHz frequencies for the "uplink" from the GSM
handset on the ground to the airborne balloon—based repeater. Frequencies currently
authorized under its experimental license will be used for the "downlink" segment from
the balloon—based repeater to the handset." Space Data requires no further amendments to
its existing experimental authorization to carry out the proposed experimental operation.

       The 895.5—895.7 MHz frequencies are assigned as Channel Block 2 spectrum
(895.6055—895.7973 MHz) and Channel Block 3 spectrum (895.4055—895.5973 MHz) in
the Air—Ground Service." As indicated above, the location for the GSM testing will be
limited to the state of Arizona, and no GSM handset used in the experiment will be
operated within 90 miles of any ground station licensed to operate with mobile stations in
the Air—Ground service Channel Block 2 or Channel Block 3 spectrum. Specifically,
only one license has been granted for access to mobile station Channel Block 3 spectrum

! 47 C.FR. § 5.59(b).
> The test would use a 200 kHz channel centered at 940.6 MHz for the "downlink" from the airborne
balloon—based repeater to the GSM handset on the ground. Space Data‘s existing experimental license
authorizes the use of this bandwidth. The GSM handset would provide a 200 kHz "uplink" transmission
centered at 895.6 MHz, in keeping with the standard 45 MHz frequency offset used with GSM base—mobile
station communications.

* See 47 C.FR. § 22.857, Table G—2 (Airborne Mobile Station Channels).


                                                                             Space Data Corporation
                                                               Modification of Experimental License
                                                                                           FCC Form 405
                                                                                               Exhibit 1
                                                                                         August 27, 2002
                                                                                             Page 2 of 3

in the state of Arizona. This license is issued to Claircom Licensee Corporation (call
sign: KNKG801, Location #117) and authorizes communications between mobile
stations installed in airplanes on the ground at the Tucson airport and a low—power (1—
watt) ground station also located at the Tucson airport (operating at 850.4055—850.6055
MHz). There are no stations licensed in the state of Arizona to operate on Channel Block
2 spectrum.*

        Space Data operations in the §95.5—895.7 MHz band will be more than adequately
separated from any Air—Ground licensee and will not create harmful interference or raise
any interference concerns. Even under worst—case conditions, the ground—level operation
of a single 2—watt GSM handset proposed by Space Data cannot present any interference
concerns to the Tucson base station located 90 miles away." Specifically, even without
any consideration for signal path losses and attenuation, a ground—based 2 watt
transmission from a GSM handset located at least 90 miles away from the Tucson airport
would have to originate at an elevation of at least 6600 feet above sea level to overcome
the curvature of the earth before it could theoretically be detected by a receiver located at
the Tucson airport. Because the ground—level elevations at all points at or beyond a 90—
mile radius of Tucson are in fact well below the minimum 6600—foot altitude at which
point interference becomes theoretically possible, interference cannot occur.°




* The nearest assigned Air—Ground Service ground station using Channel Block 2 is in Green River, UT,
more than 400 miles from the Phoenix metropolitan area.
° In the 895 MHz frequency range, the free space path loss for a distance of 90 miles is 134.5 dB
(96.6+20logD+20logF, where D is the line—of—sight distance in miles and F is the frequency in GHz). GSM
phones typically transmit at 2 watts or 36 dBm peak power (which itself is conservative since the average
power is only 0.25 watts). Without any consideration for signal losses that exist in the signal path
(mountains, trees, man—made obstructions, reflections, fading, etc.), the line—of—sight signal level in Tucson
from a GSM phone 90 miles away would be —98.5 dBm, which can be detected by most receivers.
However, once the curvature of the earth is factored into the equation (line of sight distance is D =
SQR(2*H), where D is the distance to the radio horizon in miles, H is the height of the transmitting antenna
above the ground, and SQR represents the square root), an emitter would have to be located at an altitude
4000 feet above the Tucson elevation, which is 2600 feet above sea level, in order to have a clear line—of—
sight with the Tucson airport from 90 miles away such that its signal could be detected by a receiver
located at the Tucson airport. In other words, the emitter — in this case, Space Data‘s GSM handset —
would have to be operating at an altitude of at least 6600 feet in order to create any possibility of
interference with the Claircom base station at the Tucson airport.

© Because the Air—Ground service uses the $95.5—895.7 MHz band for air—to—ground transmissions (F.e.,
from the phones installed aboard commercial aircraft to stationary base stations), the only stations that
could receive interference are Air—Ground base stations licensed on a paired basis with mobile stations
using the Channel Block 2 or Channel Block 3 spectrum. That is, the only station receiving transmissions
on any portion of the 895.5—895.7 MHz band in the state of Arizona is the ground station located at the
Tucson airport.


                                                                Space Data Corporation
                                                  Modification of Experimental License
                                                                        FCC Form 405
                                                                             Exhibit 1
                                                                        August 27, 2002
                                                                            Page 3 of 3


                            Contribution to the Radio Art

       As the Commission has recognized, large portions of the United States do not
have access to adequate telecommunications services, including emergency support
services, because provision of such services to these areas is prohibitively costly. The
Space Data system specifically is designed to offer advanced telecommunications
services to underserved and unserved areas on an affordable basis. Thus, the proposed
experimentation also will assist the Commission in finding economically viable solutions
to the complex problem of providing other types of advanced telecommunications
services to underserved areas of the United States.



Document Created: 2018-12-20 14:22:56
Document Modified: 2018-12-20 14:22:56

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