Narrative Revised

0398-EX-PL-2016 Text Documents

Tyvak Nano-Satellite Systems, Inc.

2016-07-21ELS_179718

                                  Before the
                   FEDERAL COMMUNICATIONS COMMISSION
                             Washington, DC 20554



In the Matter of                       )
                                       )
Tyvak Nano-Satellite Systems LLC       )
                                       )
Application for Authority for Ground   )
Testing, Launch, and Operation of an   )   File No. ____-EX-PL-2016
Experimental Non-Geostationary         )
Low Earth Orbit Satellite              )




                          NARRATIVE EXHIBIT


                                              Table of Contents

I.     NARRATIVE INFORMATION REQUIRED BY FCC FORM 442.................. 1
                 Question 6A. Description of the nature of the research project
                              being conducted ............................................................... 1
                 Question 6B. Showing that the communications facilities
                              requested are necessary for the research project.............. 2
                 Question 6C. Showing that existing communications facilities are
                              inadequate ........................................................................ 4
                 Question 10. Transmitting equipment to be installed, including
                              manufacturer, model number and whether the
                              equipment is experimental in nature ................................ 4
                 Question 11A. Is the equipment listed in Item 10 capable of station
                               identification pursuant to Section 5.115 .......................... 5
                 Question 4.           Antenna Registration Form. Operation of
                                       Directional Antenna ......................................................... 5
II.    RELEVANT INFORMATION ADDRESSED IN SECTION 25.114 OF
       THE COMMISSION’S RULES .......................................................................... 6
                 A. Radio Frequency Plan ......................................................................... 6
                 B. Orbital Locations............................................................................... 11
                 C. Physical Characteristics of Satellite .................................................. 11
                 D. Schedule ............................................................................................ 13
                 E. General Description of Overall System Facilities, Operations
                    and Services ...................................................................................... 13
                 F. Predicted Spacecraft Antenna Gain Contours ................................... 14
                 G. Orbital Debris Mitigation.................................................................. 15
                      1. Limiting the amount of debris released and the probability
                         of the satellite becoming a source of debris by collisions
                         with small debris ........................................................................ 15
                      2. Limiting the probability of accidental explosions during
                         and after completion of the mission operations ......................... 16
                      3. Limiting the probability of the satellite becoming a source
                         of debris by collisions with large debris or other operational
                         space stations ............................................................................. 16
                      4. Post-mission disposal plans for the space station at end of
                         life .............................................................................................. 17
III.   CONCLUSION.................................................................................................. 18


                                    Before the
                     FEDERAL COMMUNICATIONS COMMISSION
                               Washington, DC 20554


In the Matter of                               )
                                               )
Tyvak Nano-Satellite Systems LLC               )
                                               )    File No. ____-EX-PL-2016
Application for Authority for Ground           )
Testing, Launch, and Operation of an           )
Experimental Non-Geostationary                 )
Low Earth Orbit Satellite                      )


                                    NARRATIVE EXHIBIT

       Tyvak Nano-Satellite Systems LLC (“Tyvak”) uses nano-satellite and CubeSat space

vehicle to conduct tests of satellite components and for other scientific missions. With this

Application, Tyvak requests two-year authority for ground testing, launch, and operation of a

single experimental non-geostationary (“NGSO”) low earth orbit (“LEO”) CubeSat satellite.

Telemetry monitoring, tracking, and command (“TT&C”) transmissions and payload data

downlink will be carried out in the 400 MHz UHF range.1


I.     NARRATIVE INFORMATION REQUIRED BY FCC FORM 442

Question 6A. Description of the Nature of the Research Project Being Conducted

       Tyvak is internally funding a small nanosatellite attitude control experiment.      This

mission validates technologies needed to support precise near- and far-field optical imaging,

precise propulsive maneuvering and bulk data transfer while leveraging the inherent relative low

costs of their vehicle manufacture and launch capabilities.

1
 Tyvak will also file an application for experimental authority to operate an associated UHF
Earth station. Authority for additional associated UHF Earth stations may be sought by Tyvak
affiliates in separate applications, as explained below.


       The proposed satellite will adhere to a design specification co-developed by Stanford

University (“Stanford”) and California State University, San Luis Obispo (“Cal Poly”) referred

to as the CubeSat Standard. Additional information regarding the CubeSat Standard can be found

at the CubeSat Community website, http://www.CubeSat.org/.

       The spacecraft will be fabricated, tested, launched, and operated by Tyvak using its

Mission Operations Center (“MOC”) in Irvine, California, and using affiliated Earth Stations in

other locations, the authorizations for which will be secured under a separate application.2 TT&C

and payload data downlink for the satellite will be carried out by Tyvak via a two-way link in the

UHF band between 399.9-400.05 MHz. Prior to launch, Tyvak will conduct developmental

testing of satellite components, including its transmitters and receivers, at its Irvine, California

facilities. Post launch, the satellite on-orbit operations are expected to take 9 to 12 months, which

will permit adequate time to test the optics, maneuvering, and attitude control systems under

investigation.

Question 6B. Showing that the Communications Facilities Requested are Necessary for the
             Research Project

       The primary purpose of this mission is to perform a technology test of the optical system,

propulsion system, and attitude control platform. On-orbit operation is the only effective way of

collecting functional and performance data in the relevant operational environment, and cannot

be adequately substituted by ground testing or computer simulation.

       With the proliferation of the CubeSat Standard and the availability of low-cost space

access for those adhering to that standard, the cost to test miniature components on-orbit has


2
 References to Earth stations in this application are included to provide a comprehensive system
overview, but are solely advisory.

                                                 2


become relatively inexpensive compared to equivalent ground testing and simulation. This is

largely due to the availability of low-cost secondary payload launch options and cost sharing

among multiple CubeSat developers.

        In addition, on-orbit data provides confidence that future systems will operate

successfully on-orbit through maneuvers. The evaluation of hardware and software in an

environment similar to that found in space is not easily replicated on Earth. On-orbit component

failures are often attributed to unforeseen conditions or coupling of effects that cannot be tested

adequately until on-orbit. Consequently, the use of an on-orbit test bed provides significant direct

and indirect financial benefits, as well as risk reduction for future satellite programs.

Question 6C. Showing that Existing Communications Facilities are Inadequate

        Currently, there are no comparable communications facilities to support the operation of

the CubeSat system for any of the three required operations.

        For the TT&C and payload downlink in the 399.9-400.05 MHz UHF band, as discussed

in a later section of this Application, Tyvak is unaware of any currently authorized use of the

UHF band between 399.9-400.05 MHz in the United States or other countries. Thus, there are no

suitable existing facilities.

Question 10. Transmitting Equipment to be Installed, Including Manufacturer, Model
             Number and Whether the Equipment is Experimental in Nature

        The satellite has one transmitting element for which authority is being sought from the

Commission: a TT&C and payload data transceiver that operates in the UHF band between

399.9-400.05 MHz. The following graphic provides an overview of the transmitting and

receiving components. The specific model numbers are subject to change based on product

availability and system upgrades.


                                                  3


                                                                   On-board
                                                                   Processor




                                                                               CubeSat
                               UHF
                               Radio

                          Type: UHF Radio
                          Manufacturer: Tyvak
                          Model: Endeavour UHF
                          Custom

                          Type: UHF Dipole antenna
                          Manufacturer:
                          Model: Custom
                          Custom / Experimental



                                  Type: Yagi antenna array (4)
                                  Manufacturer: M2 Systems
                                  Model: 400CP30
                                  Commercially Available
                            Type: Power Amp
                            Manufacturer: TE Systems
                            Model: 4452RAS
                            Commercially Available   Power Amp


                                                           UHF
                                                           Radio
                          Mission Operations
                                Center               Type: UHF Radio
                                                     Manufacturer: ICOM
                                                     Model: IC-9100
                                                     Commercially Available

                                         Mission Operations


                  Figure 1: CubeSat System Communications Components

       The transmitting components aboard the CubeSat are controlled by a dedicated on-board

processor, which processes data for transmission, sends and receives data from the modem, and

activates the appropriate radio systems depending on the state of operations. The satellite




                                                     4


possesses a UHF system for vehicle command and telemetry retrieval and payload data

download.

       The TT&C and inter-satellite communications UHF system uses a Tyvak-developed UHF

radio derived from commercially-available UHF communications systems. The radio operates at

9,600 baud using GMSK. The UHF system will use a custom designed half-wave dipole antenna.

       The TT&C ground segment will address the satellite through the use of specific message

destination address, authentication counts and/or encryption keys using the same frequency

allocation. The transmitting component located at the Irvine Earth station is controlled by

dedicated Microsoft Windows workstations. The workstations are used for antenna pointing

control, Doppler frequency shift corrections, and data processing for transmission. The antenna

(manufacturer/model: M2 Antenna Systems, Inc./400CP30) and radio (manufacturer/model:

ICOM/IC-9100) are commercially available, off-the-shelf units, which will be modified with

additional hardware to function at the requested frequencies.

Question 11A. Is the Equipment Listed in Item 10 Capable of Station Identification
              Pursuant to Section 5.115

       Each transmitting component of the system is capable of station identification, and the

satellite will transmit its call sign in every packet transmitted as part of its frame header. The

frame header is not encoded or encrypted.

Question 4:    Antenna Registration Form; Operation of Directional Antenna

       The satellite will be a low earth orbit (“LEO”) satellite in a sun-synchronous orbital with

an orbit period of approximately 1.6 hours. The satellite will pass over the Earth station roughly

one to twelve times per day depending on its location with an average access time of five to

seven minutes for each Earth station location. The UHF Earth station will use a computer-

                                                5


controlled tracking antenna to point the Earth station’s antenna in the direction of the moving

satellite. The antenna has a maximum gain of +20.2dBi along the bore-sight of the antenna and a

half-power beam-width (i.e., -3dB) of approximately 30 degrees. The antenna array uses four

off-the-shelf, yagi-type antenna developed by M2 Antenna Systems, Inc.

         The spacecraft is an NGSO satellite, thus the range of antenna azimuth and elevation will

vary based on the relative motion of the satellite with respect to the ground station. It will also

differ for each satellite pass. The Earth station will only transmit above a 10 degree elevation

angle. Consequently, the range of antenna elevation angles for all satellite passes will be between

10 and 170 degrees. The azimuth can vary between 0 degrees and 360 degrees. Earth station

software will be used to control the antenna azimuth and elevation rotors for antenna pointing

and limit the range of permissible elevation angles. In addition, the software will be used to

predict satellite contact times and antenna pointing angles to support Earth station planning and

operations.

         In addition to on-orbit operations, the satellite components will undergo occasional

ground tests up until launch. Testing for the UHF TT&C link will be conducted in carrier

current (i.e., closed-loop) configuration and will not produce any measurable emissions.


II.      RELEVANT INFORMATION ADDRESSED IN SECTION 25.114 OF THE
         COMMISSION’S RULES

      A. Radio Frequency Plan

UHF Communications System

         The satellite’s UHF communications system will operate using half-duplex

communications within the 399.9-400.05 MHz frequency band for telecommand (i.e., earth-to-

space) and telemetry (i.e., space-to-earth). Although the satellite requires only 50 kHz of

                                                6


spectrum bandwidth, Tyvak requests herein authority to operate within the entire 399.9-400.05

MHz frequency band for the mission to facilitate design flexibility.

              The following diagram shows the proposed spectrum use of the CubeSats and ground

stations and also shows authorized spectrum uses in adjacent bands, such as the use by the

Orbcomm Little LEO MSS network of the 400.075-400.125 MHz band as a beacon frequency.

As explained below, the 399.9-400.05 MHz frequency band does not appear to be used by any

authorized government or non-government operator in the United States. Tyvak acknowledges

that the Commission has proposed to authorize operation of a federal Mobile Satellite System in

the 399.99-400.05 MHz portion of this fallow band, however, any Tyvak transmissions related to

this mission will be completed well before any Federal operations in the band commence. 3

Therefore, Tyvak’s proposed operation of its experimental satellite in 50 kHz of the 399.9-

400.05 MHz frequency band will not cause harmful interference to any authorized spectrum user.

                   400.01                                400.05

                                                                        400.075                  400.125
         399.9
                            Tyvak Cubesats


                             PRIMARY                                              Orbcomm
                     RADIONAVIGATION SATELLITE

                                PRIMARY                                      PRIMARY
                   Non-Voice, Non-Geostationary (NVNG)       STANDARD FREQUENCY AND TIME SIGNAL SATELLITE
                      Mobile Satellite Service (MSS)



    399.075         400            400.025          400.05         400.075         400.1     400.125        400.15

                                                                  MHz

                                    Figure 2: CubeSat Spectrum Diagram (UHF)




3
 See Federal Space Station Use of the 399.0-400.05 MHz Band, ET Docket No. 13-115, Notice
of Proposed Rulemaking, FCC 13-65, ¶ 63 (2013).

                                                                    7


          The 399.9-400.05 MHz frequency band is allocated internationally on a primary basis to

the Mobile Satellite Service (“MSS”) (earth-to-space). The 399.9-400.05 MHz frequency band is

also allocated internationally on a primary basis to the Radionavigation Satellite Service

(“RNSS”) until January 1, 2015.4 In the United States, the 399.9-400.05 MHz frequency band is

allocated to the MSS and RNSS services for both government and non-government use.

          During the 1995 World Radiocommunication Conference (“WRC-95”), the International

Telecommunication Union (“ITU”) allocated the 399.9-400.05 MHz band for the Little LEO

MSS service. The Commission subsequently designated the 399.9-400.05 MHz band as available

for use by Little LEO MSS networks.5 None of the applicants for Little LEO MSS licenses in the

United States, however, requested authority to operate in the 399.9-400.05 MHz band. 6

Therefore, the Commission refrained from adopting service rules for Little LEO MSS networks

operating in the 399.9-400.05 MHz band and did not issue any licenses to Little LEO MSS

networks authorizing them to operate in the band.7 Tyvak is unaware of any Little LEO MSS



4
    See 47 C.F.R. § 2.106 n.5.224B.
5
  See Amendment of Section 2.106 of the Commission’s Rules to Allocate Spectrum to the Fixed-
Satellite Service and the Mobile-Satellite Service for Low-Earth Orbit Satellites, Report and
Order, 8 FCC Rcd 1812 (1993); 47 C.F.R. §§ 2.106 n.US320 & 25.202(a)(3). Although the
Commission originally included the 399.9-400.05 MHz band in footnote US320, reference to the
399.9-400.05 MHz band was inadvertently deleted from US320 during a Commission effort to
consolidate footnotes. The Commission corrected the error, reincorporating the reference to the
399.9-400.05 MHz band in footnote US320. See Amendment of Parts 2, 25, and 73 of the
Commission’s Rules to Implement Decisions from the World Radiocommunication Conference
(Geneva, 2003) (WRC-03) Concerning Frequency Bands Between 5900 kHz and 27.5 GHz and
to Otherwise Update the Rules in this Frequency Range, Report and Order, 20 FCC Rcd 6570,
6625 (2005).
6
 See Amendment of Part 25 of the Commission’s Rules to Establish Rules and Policies
Pertaining to the Second Processing Round of the Non-Voice, Non-Geostationary Mobile
Satellite Service, Report and Order, 13 FCC Rcd 9111, 9120-21 (1997).
7
    See id. at 9121.

                                                8


network operating anywhere in the world (and particularly not in the United States) that uses the

399.9-400.05 MHz band.

       The 399.9-400.05 MHz frequency band is also allocated internationally on a primary

basis to RNSS until January 1, 2015. The 399.9-400.05 MHz frequency band was previously

used by the U.S. Department of Defense for its TRANSIT-SAT RNSS system, which was a polar

orbiting satellite network that was primarily used for commercial and government maritime

navigation. The TRANSIT-SAT network, however, was decommissioned in December 1996.8

       It does not appear that the United States government or commercial operators are using

the 399.9-400.05 MHz frequency band for any other RNSS service. As a consequence, the

399.9-400.05 MHz frequency band appears to be fallow of any authorized use in the United

States. Therefore, the short term operation of Tyvak’s experimental CubeSats will not result in

harmful interference to any authorized spectrum user.

Space-to-Earth and Earth-to-Space UHF Communications

       Despite the absence of any authorized spectrum users in the 399.9-400.05 MHz band, the

satellite has been designed to include several precautions to prevent harmful interference to other

services from space-to-Earth transmissions. First, as noted above, space-to-Earth satellite

transmissions will be controlled from the Earth station and the spacecraft will not transmit until it

receives a request from the Earth station or has on-board GPS confirmation that it is above the

designated ground station.

       Second, the satellite uplink and downlink will use the same 50 kHz bandwidth in half-

duplex mode to send digital data using standard GMSK modulation with maximum data rates up


8
 See Federal Long-Range Spectrum Plan, Working Group 7 of the NTIA Spectrum Planning
Subcommittee (Sept. 2000), available at http://www.ntia.doc.gov/osmhome/LRSP/LRSP5a.htm.

                                                 9


to 9,600 baud. The spacecraft transceiver uses a packet-based (non-continuous) communications,

which allows command reception between transmissions of packets to provide the ability to

command the satellite to cease space-to-Earth transmission operations in a timely manner, if

required.

       The satellite transmitter can be adjusted to provide up to two watts of power output when

communicating with the Earth station. Transmission power on the Earth station transmitter can

be adjusted to provide up to 200 watts of power output. The communications parameters for the

UHF communications system for the space-to-Earth and Earth-to-space links are show in the

following tables.

                    CubeSat Communications         Value
                    Parameters
                    Emission Designator            40K9G1D
                    Service                        Digital Data
                    Center Frequency               400.03 MHz
                    Requested Bandwidth            50 kHz
                    (includes Doppler)
                    Modulation                     GMSK
                    Data Rate                      9,600 bps
                    Polarization                   Linear
                    Antenna Type                   Dipole
                    Antenna Gain                   +2 dBi (Max)
                    RF Power Output                2W
                    Line/Misc Losses               -2dB
                    EIRP                           1.0 dBW
                         Table 1: Tyvak CubeSat UHF Communications
                                  Space-to-Ground Parameters
                    Earth Station                   Value
                    Communications Parameters
                    Emission Designator             40K9G1D
                    Service                         Digital Data
                    Center Frequency                400.03 MHz
                    Requested Bandwidth             50 kHz
                    (includes Doppler)
                    Modulation                      GMSK
                    Data Rate                       9,600 bps

                                              10


                   Earth Station                     Value
                   Communications Parameters
                   Polarization                      Linear (H, V) or Circular
                   Antenna Type                      Yagi array
                   Antenna Gain                      +20.2 dBi (Max)
                   RF Power Output                   200 W
                   Line Losses                       -3dB
                   EIRP                              40.2 dBW
               Table 2: Tyvak Earth Station UHF Communications Parameters

   B. Orbital Locations

       The CubeSat system comprises a single space vehicle operating in NGSO.                  The

spacecraft is intended to operate in LEO with the orbit parameters shown in Table 6. The satellite

will have an orbit period of roughly 1.6 hours with typical ground access times of five to seven

minutes per pass. The orbit parameters are presented in the following table:

                   Parameter                 Units        Value
                   Orbit Period              [hrs]        1.6 hrs
                   Orbit Altitude            [km]         610 km (circular)
                   Inclination               [deg]        97.-6 – 97.9 degrees
                                Table 4: CubeSat Orbit Parameters

   C. Physical Characteristics of the Satellite

       The space vehicle is a Nano-class satellite (< 10 kg), in which each element conforms to

the CubeSat Standard. CubeSats can be designed in different sizes as long as they are multiples

of the basic CubeSat standard unit, which is 10×10×10 centimeters, generally referred to as a 1U

CubeSat, meaning one unit in size. The satellite will consist of a single 3U CubeSats, resulting in

dimensions of approximately 30×10×10 centimeters. The CubeSat dispenser limits the total

vehicle mass of a 3U CubeSat to less than 6 kilograms. The mass budget is provided in the

following table:




                                                11


                    Component / Subsystem            Mass [g]
                    Payload                          1400
                    Spacecraft (Subtotal)            4300
                     Structure                       300
                     Electrical Power System         1500
                     Propulsion System               1400
                     ADCS                            400
                     C&DH                            100
                     Communication                   500
                     Thermal                         100
                    TOTAL                            5700
                          Table 5: CubeSat Mass Budget per Element

       For propulsion, the satellite is equipped with eight miniature cold gas thrusters. Each

thruster is fed from a common gas storage vessel with propellant capacity of 400 grams and an

initial pressurization of 83 psi (at 20degC). The thrusters are not mechanical and propulsion uses

common refrigerant (R236fa) involving no combustion. The thrusters are highly integrated with

the sensors to provide for precision maneuvering..

       For power generation, the satellite is equipped with body-mounted and deployed GaAs

solar cells that generate approximately 16 watts of power during a typical orbit. Because of the

short operational lifetime of the satellite (i.e., less than a year), the difference between the

beginning-of-life (“BOL”) and end-of-life (“EOL”) power generation is negligible. To permit

operations during eclipse, energy is stored on-board using Li-ion batteries, with power being

distributed to subsystems and components through the electrical power subsystem circuitry. The

EOL power budget is provided in the following table:

                    Component / Subsystem            EOL Power [mW]
                                                     Orbit Averaged
                    Payload                          3500
                    Spacecraft (Subtotal)            10000
                     Propulsion System               140
                     ADCS                            5000
                     C&DH                            600


                                               12


                        Communication                3500
                        Thermal                      400
                       TOTAL                         13500
                            Table 6: Power Budget per Space Vehicle

   D. Schedule

       The project timeline and major milestones for the launch and operation of the CubeSat

system are provided in the following table. The dates are approximate and contingent upon the

exact launch date (“Time of Launch” or “ToL”), orbit parameters, and unforeseen events during

on-orbit operations.

         Milestone                            Date            Notes
         Delivery for Launch Integration      July 2016       ToL - 3 months
         Pre-launch testing of transmitting   Aug 2016        ToL - 2 months
         components
         Launch                               Oct 2016        ToL + 0
         Release from launch adapter          Oct 2016        ToL + 0hr 30min
         On-orbit check                       Oct 2016        ToL + 24 hours
         Start of experiments                 Oct 2016        ToL + 4 weeks
         Decommissioning                      July 2017       ToL + 9 months
         Re-entry                             Oct 2031        ToL + 13 year
                           Table 7: CubeSat System Major Milestones

   E. General Description of Overall System Facilities, Operations and Services

       The satellite provides a platform for on-orbit testing of advanced maneuvering and

optical imaging technologies. The onboard systems on each space vehicle provide nominal

attitude, electrical power, data storage, and command function for a set of mission payloads. The

space vehicle communicates with the Earth stations through a low-rate (9.6 kbps) half-duplex

communications link operating in the UHF band.




                                               13


         The satellite will be supported by a UHF Earth station at the Irvine MOC and several

additional Earth stations operated by Tyvak affiliates at sites in North Pole, Alaska; Bozeman,

Montana; and Columbia, Maryland. Tyvak affiliates will seek authorization for each of the UHF

Earth stations in separate applications.

         The primary responsibilities of the Irvine MOC will be to command the space vehicle to

initiate the experiments, recover spacecraft engineering telemetry, and manage the function of

the spacecraft. The Earth station equipment comprises a UHF yagi antenna array and UHF

transceiver. The MOC will also have vehicle control workstations and a mission data archive

server.9 The workstations will serve as the primary interface with the ground controllers and will

be used for data processing, antenna/radio control, and engineering analysis. The mission data

archive server will archive command and telemetry data to support mission operations, status,

troubleshooting, and post-mission assessment.

      F. Predicted Spacecraft Antenna Gain Contours

         The spacecraft UHF antenna is a half wavelength L-dipole antenna, which is essentially

omni-directional when mounted on the corner of a CubeSat structure. A simulation of the

antenna design is shown in Figure 3.




9
    TT&C data and payload data will be received directly from the spacecraft via UHF link.

                                                 14


                           Figure 3: CubeSat L-Dipole UHF Antenna Gain Plot


      G. Orbital Debris Mitigation

          Because the CubeSat mission includes electro-optical imaging capabilities, Tyvak will

apply to the National Oceanic and Atmospheric Administration (“NOAA”) for a license to

operate a private remote sensing space system. Pursuant to Section 960.11 of NOAA’s rules,

NOAA is responsible for evaluating the orbital debris mitigation plans of applicants for NOAA

licenses.10 Thus, the following discussion and the orbital debris assessment report (“ODAR”)

included as an attachment to this application are for informational purposes only.

          1.     Limiting the amount of debris released and the probability of the satellite
                 becoming a source of debris by collisions with small debris

          In order to limit the amount of debris generated during normal operations, the satellite

has been designed so that all parts will remain attached to the satellite during launch, ejection,

and normal operations. This requirement is intrinsic to all satellites conforming to the CubeSat

10
     15 C.F.R. § 960.11(b)(12).

                                                  15


Standard and compliance is required for launch using the Poly-Picosatellite Orbital Deployer

(“P-POD”) system.

       The basic geometry the satellite is a monolithic cubic structure (i.e., 30cm x 10cm x

10cm) with two pairs of 30cm x 10cm deployable panels. Based on an orbital debris model (ref.

NASA DAS v2), the probability of a single particle impact with a size of 1 millimeter or larger

over the mission lifetime is very low (i.e., roughly 1.3 x 10-3). This low probability of impact for

the mission is a result of the small effective area of the space vehicle (i.e., effective area ~ 0.15

m2) and the relatively short mission duration (i.e., operational mission life less than one year).

       Catastrophic system failure due to orbital debris or micrometeoroid impact will not affect

the vehicle’s ability to de-orbit within the guidelines for vehicles operating in LEO (i.e., less than

25 years). Based on the mission orbit of 600 km, the space vehicle is anticipated to re-enter the

atmosphere within 13 year based on lifetime prediction simulations for the current mission epoch

(i.e., launch in CY2016).

       2.      Limiting the probability of accidental explosions during and after completion of
               the mission operations

       Experimentation with technologies for maneuvering and optical imaging are primary

mission objectives for the satellite. Thus, the satellite is equipped with small cold-gas propulsion

systems employing low specific impulse, low-pressure gas. The pressure vessel is made from

aluminum, has a volume of 400 ml and an initial pressurization of 83 psi (at 20degC). The vessel

has been designed to an ultimate safety factor of 2.5 times the operating pressure at maximum

storage temperature. These vessel will be fully depressurized as a part of the deorbit maneuver

process.

       In addition, the vehicle possess energy storage devices (i.e., Li-ion batteries), which will

be left in a nearly discharged state as part of the decommissioning procedure.

                                                 16


       3.      Limiting the probability of the satellite becoming a source of debris by collisions
               with large debris or other operational space stations

       Based on a simple orbital debris model (ref. NASA DAS v2), the probability of the

CubeSat colliding with large debris or other space systems of sizes one centimeter or greater at

the mission orbit altitude and inclination is negligible (i.e., roughly 4x10-6).

       The launch provider has instituted deployment procedures in order to place the co-

manifested satellites in the launch vehicle into slightly different orbits in order to reduce the risk

of collision. One of these procedures is to stagger deployment times.

       4.      Post-mission disposal plans for the space station at end of life

       The post-mission disposal plan for the CubeSat includes the transition of all vehicle

systems to a dormant state, which includes the cessation of all radio operations (i.e., transmit and

receive). Energy storage devices will be held at a minimal charge state at the end of the life of

the vehicle. All propellant remaining at end of life will be expended to initiate deorbit, resulting

in anticipated atmospheric re-entry of the satellite within 13 years of mission completion based

on its mission orbit, vehicle mass, geometry and mission epoch (i.e., launch in CY2016).

Although no active de-orbit maneuvers are required to meet the 25 year re-entry guidelines,

Tyvak anticipates accelerating de-orbit using the measures described above.

       Re-entry debris and probability of human casualty will be negligible. The materials used

on the vehicle include aluminum and PCB material, which have a relatively low melting

temperature as compared to other materials such as titanium or stainless steel, and are not

expected to survive reentry.



III.   CONCLUSION



                                                  17


       The Experimental Licensing Branch should grant Tyvak’s application for two-year

experimental authority to launch and operate a single NGSO LEO satellite, which will permit

Tyvak to test and evaluate advanced maneuvering and optical imaging technologies. Tyvak’s

experiment will not cause harmful interference to any licensed service. Tyvak will conduct its

experiment using low-power transmissions in the vacant 399.9-400.05 MHz UHF band. Further,

the Tyvak operation will meet the Commission’s orbital debris mitigation requirements.

Therefore, Tyvak’s application should be granted at the soonest practicable time.




                                               18



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Document Modified: 2016-07-21 11:20:07

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