Kepler Reply Comment

REPLY submitted by Kepler Communications Inc

Response to consolidated opposition


This document pretains to SAT-MOD-20181108-00083 for Modification on a Satellite Space Stations filing.

                                                 Before the
                                        Washington, D.C. 20554

In the Matter of                                           )
Application of Space Exploration Holdings, LLC             )       File No. SAT-MOD-20181108-00083
For Modification of Authorization for the                  )
SpaceX NGSO Satellite System                               )

To: The International Bureau


        Kepler Communications Inc. (“Kepler”) hereby submits1 these comments in reply to the

consolidated response2 of Space Exploration Holdings, LLC (“SpaceX”) to the separate petitions

of Kepler and the Commercial Smallsat Spectrum Management Association (CSSMA),3 wherein

SpaceX opposed Kepler’s Petition to conditionally deny the above-referenced application.4 The

Modification requested, inter alia, that 1,584 satellites currently authorized at 1,150 km be moved

to an altitude of 550 km, and that SpaceX expand its gateway transmissions with these satellites

into presently-unauthorized frequencies in Ku-band. In its Petition, Kepler raised its concern that

an approval of the Modification could negatively affect both the physical and radio interference

environment in the proposed 550 km region based on the influx of a significant number of new

  This document was originally submitted under IBFS File No. SAT-LOA-20170726-00110 on Feb. 22, 2019 and has
been resubmitted under IBFS File No. SAT-MOD-20181108-00083 for clarity.
  See Space Exploration Holdings, LLC. Consolidated Opposition to Petitions and Response to Comments of Space
Exploration Satellite Holdings, LLC, File No. SAT-MOD-20181108-00083 (Feb. 11, 2019) (“Response”)
  See Kepler Communications Inc., Comments and Conditional Petition to Deny of Kepler Communications Inc., IBFS
File No. SAT-MOD-20181108-00083 (Jan. 29, 2019) (“Petition”); See also CSSMA, Comments and Petition to Defer,
IBFS File No. SAT-MOD-20181108-00083 (Jan. 29, 2019).
  See Application for Modification of Authorization for the SpaceX NGSO Satellite System, IBFS File No. SAT-
MOD-20181108-00083 (Nov. 8, 2018) (“Modification”).

large satellites, the increased use of Ku-band, and the insufficient analysis provided by SpaceX

surrounding the effects of these changes. In its Response, SpaceX made the claim that the material

already provided by the Modification is sufficient for the combined petitioner’s concerns, and that

they should thus be dismissed. Kepler believes that neither the Modification, nor the Response

have addressed its concerns, nor those of the Commercial Smallsat Spectrum Management

Association (CSSMA) to which Kepler endorses.


          Kepler’s physical coordination concerns are in alignment with those of the CSSMA and it

formally supports the position taken in the CSSMA’s respective comments, including its petition

to defer, to which Kepler hereby directs the reader.5 The singular exception to this alignment is

that Kepler has, with its own Petition, formally taken a position on whether the Bureau should

grant the Modification whereas the CSSMA has not.


          In its Petition, Kepler requested that SpaceX should be required to “accept all additional

interference into its system received as a result of the modifications proposed in full, and that it

must protect all ground and space stations that would be newly victimized by the proposed

changes”, and that to do otherwise would place an unjust burden on Kepler to accommodate the

proposed modifications.6 In its Response, SpaceX did not raise opposition to Kepler’s request that

it “accept all additional interference to its system received as a result of [its] modifications”, and

thus Kepler will spend no further time on this point. With regards to the protection of Kepler’s

  See CSSMA, Joint Reply, IBFS File No. SAT-MOD-20181108-00083 (Feb. 22, 2019). See also CSSMA Petition to
Defer, supra at n. 2.
  See Petition at 5.


ground stations, SpaceX reiterated the claim made in its Modification that its newly requested use

of Ku-band for gateway transmissions would not increase the overall interference to other NGSO

FSS systems, and asserted specifically that it “should have no material effect on Kepler’s

operations”, though it did so without providing sufficient detail to support its claim.

        SpaceX first points out that Kepler’s concern for interference was not paired with an

analysis of its own. Kepler notes that such a concern does not require a quantitative analysis to be

valid in principle. As for the analysis provided in the Modification, Kepler highlighted that

SpaceX’s comparison with the IK-NGSO-A10K-1 network operating at 10,355 km was not

meaningful, to which SpaceX offered no response. To reiterate, SpaceX oddly chose the IK-

NGSO-A10K-1 network as its singular point of comparison to NGSO FSS systems in general,

despite the fact that it is neither part of the current NGSO processing round nor is it authorized by

the Commission in any other respect. SpaceX pledged that “[its] proposed modification will not

increase interference to any other NGSO system operating in the bands used by SpaceX satellites”

and yet, the single system around which it centered its analysis bears little similarity to many of

the systems in the processing round, including Kepler’s own constellation, and thus forms, on its

own, an exceedingly poor basis for a comparative evaluation of interference to the many NGSO

systems that share SpaceX’s requested bands.7

        Critically, SpaceX has made the claim multiple times that its system, as modified, will not

increase interference more so than what would have been done under its original authorization. 8

  The flaws of this analysis were further explored by others. See Petition to Deny or Defer of WorldVu Satellites
Limited (the “OneWeb petition”) at 3-4. See also Comments of SES Americom, Inc. and O3b Limited at 3-4 (the
“SES/O3b petition”).
  See Modification, Legal Narrative at i; SpaceX has broadly claimed that its modification will accomplish its
objectives “without increasing overall interference”. See also Legal Narrative at 11; SpaceX asserts that “[n]one of
SpaceX’s modifications will increase interference to other NGSOs, GSOs, or terrestrial wireless spectrum users”. See
also Modification, Technical Narrative at 24; “the proposed modification will not increase interference to any other
NGSO system operating in the bands used by SpaceX satellites”.


As much as Kepler would desire this to be true, the claim that SpaceX will cause no additional

interference at all is not supported by adequate evidence, and it would require SpaceX to assure


    1. Its wholly new utilization of Ku-band for gateway transmissions, in combination with its

         Ku user terminal links, will not produce an increased level of interference in the frequencies

         within which they operate, unless its user terminal transmissions would be proportionally

         reduced to compensate for those made in aggregate to and from its gateways 9

    2. It bears the responsibility for the execution of all conjunction avoidance maneuvers such

         that Kepler’s system would not experience an undue capacity loss resulting from needing

         to execute those maneuvers itself 10

In the absence of the second requirement specifically, and under its obligation to reject

modifications that cause additional interference, the Commission would be forced to allow Kepler

to increase its constellation size to accommodate for the reduced capacity mentioned, unless the

Commission’s non-interference requirements are themselves waived, however doing so would

break with existing precedent and be grossly unfair for other operators. As Kepler believes it

unlikely that SpaceX will cause no additional interference, its practical concern shifts to

understanding the degree to which this interference will be harmful, and an analysis undertaken to

explore these outcomes cannot be meaningfully completed without several key details surrounding

  In its Response, SpaceX claims that it “does not plan to increase the total number of beams in use at any given time
and will allocate its Ku-band downlink beams between users and gateways as necessary to optimize traffic”. Kepler
asks that SpaceX clarify this point: does SpaceX intend to reduce its user terminal beams in Ku-band to compensate
for the new use of this band for its gateway beams?
   See Kepler Communications Inc., Petition for Declaratory Ruling, IBFS File No. SAT-PDR-20161115-00114 (Nov.
15, 2016). As discussed in its application for market access, Kepler’s system uses adaptive drag managed via
spacecraft attitude for its avoidance maneuvers. The holding of these attitude configurations for maneuver execution
necessarily requires the suspension of the satellite’s commercial services, which require the spacecraft to be body-
pointed to customer terminals on the ground.


SpaceX’s newly requested use of Ku-band spectrum. For example, SpaceX claims that it will

operate only a “handful” of gateways, but Kepler has not previously been made aware any details

regarding the scope of this use. If only a “handful” of gateways are to be used, then its activity

around those stations would be reasonably expected to be high, as that limited number would be

required to support the full breadth of satellites active during its initial demonstration phase (and

perhaps those in the final phase as well; further clarification from SpaceX is needed here), and any

other operators with ground stations collocated with these gateways would therefore have

especially good reason to be concerned about the new traffic. Kepler adds that SpaceX’s elevation

angle reduction from 40 to 25 degrees during its initial demonstration phase would act to further

intensify this traffic by increasing the number of visible satellites that are permitted to transmit to

any given location, and offsetting to a significant degree the improvements obtained by the

reduction of total visible satellites achieved with its move to a lower altitude. To help elucidate

these matters, and to protect NGSO operators and therefore the public interest,11 the Commission

should require SpaceX to provide more information to substantiate its interference claims,

including, but not limited to, providing its planned number of Ku gateways, the duration of its

initial deployment phase, the extent of its use of Ku-band in its final deployment phase, and the

manner in which its gateway communications will occur, including how often satellites would

employ their gateway transmissions, the frequency bands on which they would operate, and the

method of frequency reuse across gateways and user terminals that are collocated.

        For these reasons, and to alleviate the concerns of Kepler and others, 12 SpaceX should

commit to accept all new interference made to its system as a result of its Modification, and act to

   See 47 CFR § 25.117(d)(2)(ii), and 47 CFR § 25.156(a) on the rejection of modifications on the basis that, if
implemented, would not “serve the public interest, convenience, and necessity”.
   See supra at n. 6.


protect ground stations that would be newly victimized by interference stemming from their

proposed Ku-band gateway transmissions or, alternatively, provide further details to sufficiently

demonstrate that these transmissions will not cause harmful interference to those ground stations.

Kepler believes that a commitment to these conditions, and/or the provision of the supplementary

details as described above, would act to sufficiently inform Kepler of the impacts of the

Modification, and if acceptable, serve to protect the current NGSO operating environment and the

overall public interest, and to align SpaceX’s Modification with its existing requirements to

minimize interference to other operators in the current processing round.13

Considering that similar interference concerns were raised by WorldVu Satellites Limited

(“OneWeb”) and SES Americom Inc./O3b Limited (“SES/O3b”) in their own respective

comments, Kepler takes a direct interest in the analysis that was provided to them by SpaceX in

response,14 and also wonders why its own concerns were not similarly addressed. However, the

analysis provided to the above-mentioned parties was flawed in several respects, as it did not

appear to correctly assign relevant parameters to the original and modified configurations used for

its calculations. Critically, SpaceX uses gateway transmissions in the calculations that applied to

its original authorization, which both does not reflect their actual authorized system and, by their

own admission,15 provides a worse assumption than if it were to use user terminals, and in doing

   See Space Exploration Holdings, LLC, Application for Approval for Orbital Deployment and Operating Authority
for the SpaceX NGSO Satellite System; Application for Approval for Orbital Deployment and Operating Authority
for the SpaceX NGSO Satellite System Supplement, Memorandum Opinion, Order and Authorization, 33 FCC Rcd
3391 (2018).
   See Space Exploration Holdings LLC, Further Consolidated Opposition to Petitions and Response to Comments of
Space Exploration Holdings, LLC, IBFS File No. SAT-MOD-20181108-00083 (Feb. 21, 2019). SpaceX provided an
analysis centered around the proposed systems of OneWeb and SES/O3b.
   See Id. at A-1. SpaceX states “the analysis assumes that the SpaceX earth station is a gateway rather than a user
terminal. This is a worst-case assumption because SpaceX satellites can transmit only one co-frequency, co-polar
beam to a user terminal, but can transmit up to four such beams in the Ku-band and up to eight such beams in the Ka-


so, SpaceX artificially inflates the severity of the I/N values for its original configuration and thus

corrupts the comparison it makes to its modified system.

Further, the analysis took great pains to ensure it was using many other worst-case assumptions

that appear to favor the victim,16 but Kepler notes these conditions only affect the absolute level

of interference experienced by simulated victim stations, and in fact have zero effect on the relative

difference between its original and modified configurations, serving better as a distraction to the

reader than they do as a useful contribution. Therefore, Kepler believes these analyses were

fundamentally misleading and do not adequately address the interference concerns of the parties

to which they were addressed, many of which Kepler shares. This remains especially true in

Kepler’s case, as its constellation is not sufficiently similar to those proposed by OneWeb and

SES/O3b to draw reliable comparisons from the analyses they were provided.17

         Finally, Kepler wishes to echo the concerns of OneWeb regarding SpaceX’s EPFD

showing, and notes that to Kepler’s knowledge, SpaceX does not appear to have filed its modified

orbital characteristics with the ITU, and Kepler thus has no means to evaluate the full EPFD

characteristics of the modified proposal, including its associated masks.

   See Id. Among others, assumptions included the use of high gain victim antennas, the exclusion of atmospheric
attenuation, and the direction of mainbeams to the SpaceX systems that are closest to victim receiving antennas.
   For example, OneWeb’s constellation uses a 45° elevation mask on uplink and downlink, and thus its potential for
new interference caused by SpaceX’s widening of its own elevation mask from 40° to 25° is geometrically limited. A
similar type of discrepancy occurs with a comparison to O3b’s system, which from an interference-area perspective
appears similar to the GEO arc. Kepler’s interference-area profile resembles neither of these systems, and thus cannot
be compared effectively.



        For the reasons discussed above, Kepler remains unpersuaded that the information already

contained in the Modification is sufficient to alleviate its concerns. To alleviate these, SpaceX


   1. Accept any new interference to its system received as a result of the changes requested by

        its Modification and,

   2. Guarantee that Kepler earth stations will not receive additional interference as a result of

        its proposed use of Ku-only gateway links or, at minimum, be required to supply an

        analysis to adequately demonstrate that their use of the gateway links will, as they have

        claimed, not cause any more interference than would have been caused by their user

        terminals alone in that band, in accordance with the suggestions made herein.

If these conditions are met, then Kepler will be persuaded that it will not be unduly forced to

modify its own system to accommodate the changes proposed by the Modification, and will have

no further reason to justify its associated Petition to Deny.

Respectfully Submitted

/S/ Nickolas G. Spina
Nick G. Spina
Director, Launch & Regulatory Affairs


                                CERTIFICATE OF SERVICE

       I hereby certify that, on February 22, 2019, a true and correct copy of these comments
was sent via Canada Post, first class postage prepaid, to the following:

 William M. Wiltshire                                 Tim Hughes
 Paul Caritj                                          Senior Vice President, Global
 Harris, Wiltshire, & Grannis LLP                     Business and Government Affairs
 1919 M Street NW                                     Space Exploration Technologies Corp.
 Suite 800                                            1155 F Street NW
 Washington, DC 20036                                 Suite 475
                                                      Washington, DC 20004
 Counsel for SpaceX

                                                      Patricia Cooper
                                                      Vice President of Satellite Government Affairs
                                                      Space Exploration Technologies Corp.
                                                      1155 F Street NW
                                                      Suite 475
                                                      Washington, DC 20004

                                                      /s/ Shane Laverty
                                                     Shane Laverty

Document Created: 2019-02-24 08:59:50
Document Modified: 2019-02-24 08:59:50

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