Attachment Exhibit B

This document pretains to SES-MOD-20101208-01520 for Modification on a Satellite Earth Station filing.

IBFS_SESMOD2010120801520_855914

                                                         Comtech Mobile Datacom Corporation
                                                                              FCC Form 312
                                                                       Exhibit B, Page 1 of 7
                                                           E990143 Modification Application


                                      Request for Waiver


        Comtech Mobile Datacom Corporation ("CMDC") requests a waiver of footnotes US308
and US315 to the U.S. Table of Frequency Allocations and Section 25.136(d) of the
Commission‘s Rules. These provisions are intended to protect maritime mobile—satellite service
distress and safety communications in the lower L—band and aeronautical mobile—satellite service
distress and safety communications in the upper L—band from interference.

         As discussed below, the CMDC terminals that are the subject of this Application (all
half—duplex) comply with the requirements listed in Section 25.136(d) of the Commission‘s
Rules for the protection of maritime mobile—satellite service distress and safety communications
in the lower L—band, and the equivalent requirements for the protection of aeronautical mobile—
satellite service distress and safety communications in the upper L—band as set forth in the
NTIA/FAA Letter.‘ However, a small number of terminals —— approximately 900 terminals, all
CMDC‘s model MTM202 —— do not comply with the National Telecommunications and
Information Administration‘s ("NTIA‘s") interpretation of footnotes US308 and US315. NTIA
determined in the NTZA 2009 Letter that if a terminal meets certain minimum requirements and is
capable of ceasing transmissions and inhibiting further transmissions within three (3) seconds,
that terminal would be considered to meet the real time access and priority preemption
requirements in footnotes US308 and US315. Worst case, CMDC‘s MTM202 terminals take
3.6 seconds — only .6 seconds longer than the NTIA requirement — to cease transmissions within
when operated outside of the continental U.S. ("CONUS"). All other CMDC MET‘s, including
the MTM202 when operated in CONUS, satisfy the NTIA requirement.

       CMDC demonstrates below that there is good cause for granting a waiver of footnotes
US308 and US315 as well as Section 25.136(d). Accordingly, CMDC respectfully requests that
the Commission grant this waiver request.


Description of CMDC System

       CMDC provides wireless packet data services from mobile terminals throughout the
United States and overseas. CMDC terminals typically are placed on land vehicles or at remote,

1       See Amendment of Part 87 of the Commission‘s Rules to Establish Technical Standards
        and Licensing Procedures for Aircraft Earth Stations, 8 FCC Red 3156, [ 5, n. 22 (1993),
        citing Letter from Richard D. Parlow, Associate Administrator, Office of Spectrum
        Management, NTIA, and Gerald Markey, Manager, Spectrum Engineering Division,
        FAA to Cheryl Tritt, Chief, Common Carrier Bureau, FCC, dated January 14, 1993
        ("NTIA/FAA Letter").
        See Letter of Karl B. Nebbia, Associate Administrator, Office of Spectrum Management,
        U.S. Department of Commerce, NTIA, to Mr. Julius Knapp, Chief, Office of Engineering
        and Technology, FCC, May 13, 2009 ("NTIA 2009 Letter‘).



DCOLGRIFJMA29257.2


                                                            Comtech Mobile Datacom Corporation
                                                                                 FCC Form 312
                                                                          Exhibit B, Page 2 of 7
                                                              E990143 Modification Application

fixed site locations. Either data collection devices or keyboard/displays, or both, may be
attached to the terminals depending on the customers‘ needs in that location or at that time.

        The terminals transmit and receive data packets via L—band dedicated channels. CMDC‘s
system is capable of using L—band channels from any carrier providing such services in the U.S.
The packets can be routed over any of several terrestrial data networks, or to other mobile
transceivers in the CMDC network. Use of the satellite relay is as a "bent pipe," meaning that
only bandwidth and power are purchased from the satellite relay operator. Network management
is provided by CMDC—owned and operated gateway sites.

        The wireless packet data network is bi—directional, and transmission can be asynchronous
in both directions. When powered on, terminals are either listening for packets addressed to
them — individually or in groups — from a gateway station, or are transmitting packets in short
bursts to a gateway station. Other modes of operation are possible, including periodic reporting
from a terminal to a customer‘s operation center, via a gateway, and polled queries to the
terminals by either the gateway or operation center.

        The mobile transceivers transmit and receive direct sequence spread spectrum bursts. In
CONUS, the typical burst duration is less than 100 milliseconds, while the maximum burst
duration is about 400 milliseconds. In Alaska, Hawaii, and U.S. possessions and territories
within the footprint of the satellite, a reduced data rate service is employed that results in a
maximum burst duration of 1.6 seconds. Bursts from any individual transceiver are usually a
minimum of several minutes apart. This means that the maximum interval during which a
transceiver will not be listening to the outbound channel is less than 0.4 seconds (1.6 seconds in
Alaska, Hawaii, and U.S. possessions and territories within the footprint of the satellite), and
represents only a small fraction of one percent of its operating time.

        In normal operation, a packet of information sent by a mobile terminal will be received
by the CMDC gateway station, then routed to the designated recipient via the Internet, dedicated
links, or the CMDC network outbound channel. There are no constraints on the routing of
packets, though mobile—to—mobile, mobile—to—operation center, and operation center—to—mobile
represent the majority of the traffic.

         The mobile terminals can be tuned to transmit and receive across the entire L—band. This
is to facilitate access to available bandwidth on the satellite relays, since the satellites operate
many beams, and any one frequency may not be available across all beams. The outbound
beams broadcast their identity in the form of network management packets from which the
mobile terminal can determine what transmission frequencies are available for use. The
operating frequencies may be changed by command from the gateway stations. Also, a mobile
terminal can only transmit when its receiver is locked onto a CMDC forward link.

        The network management function of the CMDC network is provided by CMDC‘s 24/7
Network Operations Center in Germantown, MD. This function includes monitoring traffic,
setting and adjusting operating frequencies, and activating a system wide shut—down capability




DCOLGRIFJMA29257.2                               2


                                                           Comtech Mobile Datacom Corporation
                                                                                FCC Form 312
                                                                         Exhibit B, Page 3 of 7
                                                             E990143 Modification Application

for individual or multiple service regions as required. The shut—down can be accomplished by
either CMDC personnel, locally or remotely, as well as by the satellite operator.


Compliance with Section 25.136(d)

       The following paragraphs explain CMDC‘ s compliance with Section 25.136(d) of the
Commission‘s Rules, which address the protection of maritime mobile—satellite service distress
and safety communications in the lower L—band.

        Section 25.136(d)(1). All MES transmissions shall have a priority assigned to
        them that preserves the priority and preemptive access given to maritime distress
        and safety communications sharing the band.

        This requirement is not applicable, as CMDC‘s MESs operate only on dedicated channels
that are not shared with any distress or safety communications.

        Section 25.136(d)(2). Each MES with a requirement to handle maritime distress
        and safety data communications shall be capable of either: (i) recognizing
        message and call priority identification when transmittedfrom its associated LES
        or (ii) accepting message and call priority identification embedded in the message
        or call when transmitted from its associated LES and passing the identification to
        shipboard data message processing equipment.

        This requirement is not applicable, as CMDC‘s MESs are not required to handle distress
or safety communications.

        Section 25.136(d)(3). Each MES shall be assigned a unique terminal
        identification number that will be transmitted upon any attempt to gain access to
        a system.

        CMDC‘s terminals comply with this requirement. Each CMDC MES is part of a virtual
private network with a distinct identity.

        Section 25.136(d)(4). After an MES has gained access to a system, the mobile
        terminal shall be under control of a LES and shall obtain all channel assignments
        from it.

       CMDC‘s terminals comply with this requirement. After connecting to an associated LES
system, the CMDC MESs obtain control and frequency tuning commands over the
communication channel only from that LES.




DCOLGRIFJMA29257.2                              3


                                                           Comtech Mobile Datacom Corporation
                                                                                FCC Form 312
                                                                         Exhibit B, Page 4 of 7
                                                             E990143 Modification Application

        Section 25.136(d)(5). All MESs that do not continuously monitor a separate
        signalling channel or signalling within the communications channel shall monitor
        the signalling channel at the end of each transmission.

       CMDC‘s terminals comply with this requirement. The CMDC MESs are a half—duplex
RF system operating on dedicated channels and when not transmitting are continuously
monitoring the LES for command signals.

        Section 25.136(d)(6). Each MES shall automatically inhibit its transmissions if it
        is not correctly receiving separate signalling channel or signalling within the
        communications channel from its associated LES.

        CMDC‘s terminals comply with this requirement. As noted previously, a CMDC MES
will not transmit unless it is properly receiving and locked onto the incoming RF signal from its
associated LES.

        Section 25.136(d)(7). Each MES shall automatically inhibit its transmissions on
        any or all channels upon receiving a channel—shut—off command on a signalling
        or communications channel it is receiving from its associated LES.

       CMDC‘s terminals comply with this requirement. A CMDC MES will not transmit if it
has been disabled by a control signal from the associated LES.

        Section 25.136(d)(8). Each MES with a requirement to handle maritime distress
        and safety communications shall have the capability within the station to
        automatically preempt lower precedence traffic.

        This requirement is not applicable, as CMDC‘s MESs are not required to handle distress
or safety communications.


Compliance with NTIA/FAA Letter Requirements

        The following paragraphs explain CMDC‘ s compliance with the requirements set forth in
the enclosure to the NTIA/FAA Letter. These requirements address the protection of aeronautical
mobile—satellite service distress and safety communications in the upper L—band.

        1. All MES transmissions shall have a priority assigned to them that preserves
        the priority and preemptive access given to aeronautical distress and safety
        communications sharing the band.

        This requirement is not applicable, as CMDC‘s MESs operate only on dedicated channels
that are not shared with any distress or safety communications.




DCOLGRIFJMA29257.2                              4


                                                           Comtech Mobile Datacom Corporation
                                                                                FCC Form 312
                                                                         Exhibit B, Page 5 of 7
                                                             E990143 Modification Application

        2. Each MES with a requirement to handle distress and safety data
        communications shall be capable of recognizing message and call priority
        identification when transmitted from its associated LES.

        This requirement is not applicable, as CMDC‘s MESs are not required to handle distress
or safety communications.

        3. Each MES shall be assigned a unique terminal identification number that will
        be transmitted upon any attempt to gain access to a system.

        CMDC‘s terminals comply with this requirement. Each CMDC MES is part of a virtual
private network with a distinct identity.

        4. After an MES has gained access to a system, the mobile terminal shall be
        under control of an LES and shall obtain all channel assignments from it.

       CMDC‘s terminals comply with this requirement. After connecting to an associated LES
system, the CMDC MESs obtain control and frequency tuning commands over the
communication channel only from that LES.

        5. All MESs that do not continuously monitor a separate signalling channel shall
        have provision for signalling within the communications channel.

       CMDC‘s terminals comply with this requirement. The CMDC MESs are a half—duplex
RF system operating on dedicated channels and when not transmitting are continuously
monitoring the LES for command signals.

        6. Each MES shall automatically inhibit its transmissions if it is not correctly
        receiving a separate signalling channel or signalling within the communications
        channel from its associated LES.

        CMDC‘s terminals comply with this requirement. As noted previously, a CMDC MES
will not transmit unless it is properly receiving and locked onto the incoming RF signal from its
associated LES.

        7. Each MES shall automatically inhibit its transmissions on any or all channels
        upon receiving a channel—shut—off command on a signalling or communications
        channel it is receiving from its associated LES.

       CMDC‘s terminals comply with this requirement. A CMDC MES will not transmit if it
has been disabled by a control signal from the associated LES.




DCOLGRIFJMA29257.2                              5


                                                            Comtech Mobile Datacom Corporation
                                                                                 FCC Form 312
                                                                          Exhibit B, Page 6 of 7
                                                              E990143 Modification Application

        8. Each MES with a requirement to handle distress and safety—related
        communications shall have the capability within the station to automatically
        preempt lower precedence traffic.

        This requirement is not applicable, as CMDC‘s MESs are not required to handle distress
or safety communications.


Compliance with NTIA interpretation regarding real time access and priority preemption

        As noted previously, NTIA has indicated that it will consider a terminal to satisfy the real
time access and priority preemption requirements in footnotes US308 and US315 if the terminal
is capable of, among other things, ceasing transmissions and inhibiting further transmissions
within three (3) seconds. CMDC interprets this benchmark as meaning that each MES for all of
its operating modes must, within three (3) seconds of receiving a shutdown command or losing
lock on the downlink, stop all ongoing RF transmissions and prevent any new RF transmissions.

         In Alaska and Hawaii, CMDC‘s MTM202 is programmed to operate at 4 data rate. The
data rate is set by CMDC‘s signal set and not by the individual operating the terminal. Operation
at a slower data rate is necessary in these locations to compensate for the reduced availability of
satellite bandwidth in these locations. At 4 data rate, the transmission duration for a full length
message (128 bytes) from a MTM202 is 1.6 seconds.

       The MTM202 incorporates a two—second timeout parameter. The two—second timeout
parameter means that when a MTM202 detects a loss of forward link (the link from the hub
station to the MES), the MES will continue to monitor the forward link for an additional two
seconds to confirm that the carrier is down before disabling the transmitter. As such, these
MESs require a maximum of 3.6 seconds outside of CONUS to stop all ongoing transmissions
and prevent any new transmissions. All other CMDC MET‘s, including the MTM202 when
operated in CONUS, satisfy the NTIA shutdown requirement.


Waiver Request

        Section 1.3 of the Commiuission‘s Rules authorizes the Commission to waive its rules for
"good cause shown.‘"" In general, the Commission will grant a waiver ofits rules if the relief
requested would not undermine the policy objective of the rule in question and would otherwise
serve the public interest.* In the CMDC Order, the Commission granted CMDC‘s waiver on the
basis that (a) CMDC‘s half—duplex terminals will not adversely affect current aeronautical and
maritime safety operations in the L—band; (b) CMDC operates on dedicated channels; and (c) the

3       47 CFR § 1.3.
*       See Comtech Mobile Datacom Corp., Order and Authorization, IB File No. SES—AMD—
        20070907—01251, DA 09—906, rel. May 15, 2009 ("CMDC Order‘) at Y 4.


DCOLGRIFJMA29257.2                               6


                                                             Comtech Mobile Datacom Corporation
                                                                                  FCC Form 312
                                                                           Exhibit B, Page 7 of 7
                                                               E990143 Modification Application

extent and number of the operations that do not meet the one—second criteria are limited." The
Commission found that "under these circumstances, requiring [CMDC] to terminate those
limited operations that do not meet the one—second criteria, or to employ an alternative (and more
expensive) full—duplex system for those operations, or to employ a full—duplex system for all of
the systems because of the limited noncompliance of a few stations on a few occasions, would
impose an undue economic burden in light of the absence of harm in this case.""

        The CMDC Order provides precedent for grant of this waiver request. All of the findings
on which the Commission based its decision to grant a waiver in the CMDC Order remain valid
today. There are only about 900 MTM202 terminals in existence today. Worst case, each
MTM202 terminal takes only 3.6 seconds — only .6 seconds longer than the NTIA requirement —
to cease transmissions when operated outside of CONUS."

       Importantly, the MTM202 is at end of life; while CMDC is selling units in stock, it is not
building any new units. All the MTM202 terminals operate on dedicated channels transmitting
only short bursts of data and using dedicated frequencies that are not assigned to and cannot
cause interference to services provided in the GMDSS or the AMS(R)S. CMDC notes that it has
never received any complaints of interference regarding the operation of its half—duplex MET‘s.
As such, the Commission‘s conclusion in the CMDC Order that a grant of CMDC‘s requested
waiver would not result in any harmful or undue interference to aeronautical and maritime safety
operations in the L—band is still valid.

       At the same time, grant of this waiver request will serve the public interest. The U.S.
Army‘s Force XXI Battle Command, Brigade and Below ("FBCB2") command and control
system, also known as Blue Force Tracking ("BFT"), operates the MTM202 MET‘s in the U.S.
and worldwide. Grant of this waiver request will enable the U.S. Army to continue using their
MTM202 MET‘s on MSAT—1 and MSAT—2, and will permit CMDC to continue to provide
requested services to the U.S. Army. As before, requiring CMDC to terminate these operations
or deploy alternative equipment would impose an undue economic burden in light of the
circumstances.

        In light of these facts, it is clear that there is good cause for grant of CMDC‘ s waiver
request. CMDC respectfully asks that the Commission grant this request.




°       CMDC Order at 7.
°       CMDC Order at 7.
7       The CMDC Order at [ 7 requires CMDC to submit an analysis of its MET operations
        since the grant of the CMDC Order showing the number of packets each month having a
        transmission duration of 1 second or longer since the release of the CMDC Order.
        CMDC is preparing this analysis and expects to submit it within the next two (2) weeks.


DCOLGRIFJMA29257.2                                7



Document Created: 2019-05-23 05:46:22
Document Modified: 2019-05-23 05:46:22

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