CPOD Narrative Document

0177-EX-CN-2016 Text Documents

Tyvak Nano-Satellite Systems, Inc.

2016-10-25ELS_183645

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 ) File No. ____-EX-PL-2016 Experimental Non-Geostationary ) Low Earth Orbit Satellites ) 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 .............. 3 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 .......................... 6 Question 4. Antenna Registration Form. Operation of Directional Antenna ......................................................... 7 II. RELEVANT INFORMATION ADDRESSED IN SECTION 25.114 OF THE COMMISSION’S RULES .......................................................................... 8 Section 25.114(c)(4)(1) Radio Frequency Plan ....................................... 8 Section 25.114(c)(5)(1) Orbital Locations ............................................ 15 Section 25.114(c)(10) Physical Characteristics of Satellites ................. 16 Section 25.114(c)(12) Schedule............................................................. 17 Section 25.114(d)(1) General Description of Overall System Facilities, Operations and Services ................................ 18 Section 25.114(d)(3) Predicted Spacecraft Antenna Gain Contours ..... 19 Section 25.114(d)(14) Orbital Debris Mitigation .................................. 21 Section 25.114(d)(14)(i) Limiting the amount of debris released during normal operations and the probability of the satellite becoming a source of debris by collisions with small debris or meteoroids that could cause loss of control and prevent post-mission disposal ......... 21 Section 25.114(d)(14)(ii) Limiting the probability of accidental explosions during and after completion of the mission operations ......................................................... 22 Section 25.114(d)(14)(iii) Limiting the probability of the satellite becoming a source of debris by collisions with large debris or other operational space stations ...................... 22

Section 25.114(d)(14)(iv) Post-mission disposal plans for the space station at end of life ....................................................... 23 III. CONCLUSION.................................................................................................. 23 ii

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 ) Experimental Non-Geostationary ) Low Earth Orbit Satellites ) NARRATIVE EXHIBIT Tyvak Nano-Satellite Systems LLC (“Tyvak”) provides nano-satellite and CubeSat space vehicle products and services that target advanced state-of-the-art capabilities. With this Application, Tyvak requests two-year authority for ground testing, launch, and operation of a pair of identical experimental non-geostationary (“NGSO”) low earth orbit (“LEO”) CubeSat satellites. The RF communications links for these satellites include low-power transmissions in the 2.4 GHz Industrial, Scientific, and Medical (“ISM”) band for inter-satellite ranging; two-way telemetry monitoring, tracking, and command (“TT&C”) transmissions and inter-satellite communications 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 1 Tyvak will also file an application for experimental authority to operate an associated UHF Earth station.

Tyvak has been selected by NASA to execute the Proximity Operations Nano-Satellite Flight Demonstration (“PONSFD”) project under NASA’s Edison Small Satellite Flight Demonstration Missions program, government contract number NNA12AC39C. The project name has since been updated to the CubeSat Proximity Operations Demonstration (“CPOD”). The CPOD project validates the technologies needed to support rendezvous, proximity operations, docking (“RPOD”), servicing, and formation flight by utilizing a pair of identical nano-satellites, and leveraging the inherent relative low costs of their vehicle manufacture and launch capabilities. The proposed satellites 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 for the satellites will be carried out by Tyvak via a two-way link in the UHF band between 399.9- 400.05 MHz. The UHF link will also be used for communications between the two satellites at a significantly reduced power level. Finally, the satellites will conduct ranging determinations between the two satellites using low-power commercial-off-the-shelf (“COTS”) ISM transmitters in the 2.4 GHz range. The 2.4 GHz system may also be used for some inter-satellite communications, as an alternative to the primary UHF inter-satellite link. 2 References to Earth stations in this application are included to provide a comprehensive system overview, but are solely advisory. 2

Prior to launch, Tyvak will conduct developmental testing of satellite components, including its transmitters and receivers, at its Irvine, California facilities. Post launch, the satellites are intended to be short-lived, with an expected lifespan of 9 to 12 months on-orbit, which will permit adequate time to demonstrate the inter-satellite link and rendezvous operations under investigation. Question 6B. Showing that the Communications Facilities Requested are Necessary for the Research Project The primary purpose of this mission is to demonstrate proximity operations, such as relative station-keeping, circumnavigation, and docking. 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 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 to customers 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 3

Currently, there are no comparable communications facilities to support the operation of the CubeSat system for any of the three required operations. For the inter-satellite ranging operation in the 2.4 GHz ISM band, no existing facilities can be used for this purpose because a primary mission objective is to test inter-satellite ranging capabilities during on-orbit proximity operations. For the TT&C and inter-satellite communications link 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 Each of the two identical CubeSats comprise two transmitting elements for which authority is being sought from the Commission: a) an inter-satellite ranging component that transmits and receives in the ISM band at 2.4 GHz; and b) a TT&C and inter-satellite communications component that transmits and receives in the UHF band between 399.9-400.05 MHz. The following graphic provides an overview of the transmitting and receiving components of each element. The specific model numbers are subject to change based on product availability and system upgrades. 4

On-board Processor ISM Band Radio CubeSat 1 Type: ISM Transceiver Manufacturer: NanoTron CubeSat 2 UHF Model: nanoPan Radio Commercially Available Type: UHF Radio Type: ISM Power Amplifier Manufacturer: Tyvak Manufacturer: Shireen Model: Endeavour UHF Model: 1W OEM High Gain Custom Amplifier Module Commercially Available Type: UHF Dipole antenna Manufacturer: Type: ISM Patch Model: Custom Manufacturer: Taoglas Custom / Experimental Model: WLP.2450.25.4.A.02 Commercially Available Type: Yagi antenna array (4) Manufacturer: M2 Systems Model: 400CP30 Commercially Available Type: Power Amp Manufacturer: TE Systems Model: 4452RAS Power Amp Commercially Available UHF Radio Mission Operations Type: UHF Radio Manufacturer: ICOM Center Model: IC-9100 Commercially Available Mission Operations Figure 1: CubeSat System Communications Components The transmitting components aboard the CubeSats 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. Each vehicle 5

possesses a COTS ISM band system for inter-satellite ranging, a UHF system for vehicle command, telemetry retrieval, and inter-satellite communications. The two satellites will use the same spectrum. The inter-satellite ISM system uses a ceramic surface mount patch antenna from Taoglas. This is an off-the-shelf RHCP antenna with a gain of 5dBi, and a -10dB RL bandwidth of 85 MHz. 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 from 9,600 baud up to 19,200 baud using GMSK. The UHF system will use a custom designed half-wave dipole antenna. The TT&C ground segment can address each unit or both units through the use of different message destination addresses, 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 at the end of each complete transmission. The station identification process is incorporated into the mission operations procedure. The space component will transmit in Morse code the assigned call sign at the end of each complete data transmission. The space component also transmits the call sign in 6

every packet transmitted as part of its frame header. The frame header is not encoded or encrypted. The ground component will broadcast in clear voice the assigned call sign at the end of each data transmission by ground station operators. Question 4: Antenna Registration Form; Operation of Directional Antenna The CubeSats are low earth orbit (“LEO”) satellites in a sun-synchronous orbital with an orbit period of approximately 1.6 hours. The satellites 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-controlled tracking antenna to point the Earth station’s antenna in the direction of the moving satellites. The antenna has a maximum gain of +16.2dBi 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. Because the CubeSats are NGSO satellites, the range of antenna azimuth and elevation will vary based on the relative motion of the satellites 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 developmental testing at Tyvak’s Irvine, CA facility beginning in November 2016. Testing for the 2.4 GHz 7

ranging transmitters and the UHF TT&C and inter-satellite communications link will be conducted in carrier current (i.e., closed-loop) configuration and will produce only unintentional emissions. Under the Commission’s rules, unintentional radiators operating in the frequency range between 9 kHz to 30 MHz must comply with the radiated emission limits for intentional radiators as provided in 47 C.F.R. § 15.209.3 As Tyvak’s test program may marginally exceed these limits, Tyvak seeks experimental authority for emissions in the appropriate ranges at the Tyvak facility. These developmental tests are expected to begin in November 2016. II. RELEVANT INFORMATION ADDRESSED IN SECTION 25.114 OF THE COMMISSION’S RULES Section 25.114(c)(4)(i) Radio Frequency Plan UHF Communications System The CubeSats’ 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), telemetry (i.e., space-to-earth), and inter-satellite (i.e. space-to-space) communications. Although the CubeSats require only 16.5 kHz of 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 3 47 C.F.R. § 15.109(e). 8

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. 4 Therefore, Tyvak’s proposed operation of its experimental satellites 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: CubeSats Spectrum Diagram (UHF) 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, 2015.5 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. 4 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). 5 See 47 C.F.R. § 2.106 n.5.224B. 9

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.6 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.7 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.8 Tyvak is unaware of any Little LEO MSS 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 6 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). 7 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). 8 See id. at 9121. 10

satellite network that was primarily used for commercial and government maritime navigation. The TRANSIT-SAT network, however, was decommissioned in December 1996.9 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 CubeSats have 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. 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 to 19,200 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 9 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. 11

adjusted to provide up to 180 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 16K5G1D Service Digital Data Center Frequency 399.92 MHz Requested Bandwidth 50 kHz (includes Doppler) Modulation GMSK Data Rate 19,200 bps Polarization Linear Antenna Type Dipole Antenna Gain +2 dBi (Max) RF Power Output 2W Line/Misc Losses -2dB EIRP 3.0 dBW Table 1: Tyvak CubeSat UHF Communications Space-to-Ground Parameters Earth Station Value Communications Parameters Emission Designator 16K5G1D Service Digital Data Center Frequency 399.92 MHz Requested Bandwidth 50 kHz (includes Doppler) Modulation GMSK Data Rate 19,200 bps Polarization Linear (H, V) or Circular Antenna Type Yagi array Antenna Gain +16.2 dBi (Max) RF Power Output 180 W Line Losses -3 dB EIRP 35.8 dBW Table 2: Tyvak Earth Station UHF Communications Parameters 12

Inter-Satellite Space-to-Space UHF Communications The satellites will only initiate space-to-space communications upon a command from the MOC using UHF TT&C links. However, the space-to-space link can continue intermittent, low power communications throughout the orbit to pass relative position or vehicle state information between the spacecraft, including when they are not in contact with an Earth station. Thus, in the unlikely event that potential interference is reported, the Tyvak MOC would issue the command to cease transmission during the next contact period, which will occur one to twelve times per day at intervals of one to twelve hours. The UHF transmitter will provide up to 100 mW of power output when communicating between the satellites. Based on the power levels to be used with the inter-satellite link, the maximum energy received at the surface of the Earth will not exceed -148 dBW. The table below shows a link budget for the worst case power flux density at the ground during space-to-space transmission. Item Value Comments From LEO 620km LEO orbit To GND Transmit power for Inter Satellite Link Transmit Power (Watts) 0.1 over UHF Frequency, GHz 0.4 400 MHz Satellite Line Loss to Antenna, dB -2 Coax, filtering, balun Transmit Antenna Gain, dBic 2 Isotropic Antenna Satellite Antenna Pointing Loss 0.0 Peak gain oriented Nadir Transmitter EIRP, dBW -10.0 620km altitude, 90 degree angle of Slant Range, km 620 arrival (δ) Path Loss, dB -140.3 Atmospheric Loss, dB -0.3 13

-148dBW/m2 allowed under 5.268 of Signal power at the ground -150.7 NTIA Redbook for an adjacent band (410-420 MHz) Table 3: Power Flux Density for Space-to-Space Transmissions The communications parameters for the UHF communications system for the space-to- space inter-satellite link are show in the following table. CubeSat Value Communications Parameters Emission Designator 16K5G1D Service Digital Data Center Frequency 400.03 MHz Requested Bandwidth 50 kHz (includes Doppler) Modulation GMSK Data Rate 19,200 bps Polarization Linear Antenna Type Dipole Antenna Gain +2 dBi (Max) RF Power Output 100 mW Line/Misc Losses -2dB EIRP -10.0 dBW Table 4: Tyvak CubeSat UHF Inter-satellite Link Parameters Inter-Satellite Ranging System The CubeSats’ inter-satellite ranging system will operate using COTS-based transceivers within the 2.4 GHz ISM frequency band. The COTS transceiver, nanoPan 5375, by Nanotron (www.nanotron.com)10 provides ranging and communications functions. 10 FCC ID SIFNANOPAN5375V1, Granted Mar. 26, 2009. 14

CubeSat Value Communications Parameters Emission Designator 80M0V1D Service Digital Data Frequency Band 2.4 GHz ISM band Requested Bandwidth 80 MHz (includes Doppler) Modulation Chirp Spread Spectrum (CSS) - Proprietary Data Rate 250 kbps Polarization RHCP Antenna Type Patch Antenna Gain +5 dBic (Max) RF Power Output 1W Line Losses -1dB EIRP +4 dBW Table 6: Tyvak CubeSat ISM Communications Parameters Section 25.114(c)(5)(i) Orbital Locations The CubeSat system comprises two space vehicles operating in NGSO. The spacecraft will be connected together when deployed from the launch vehicle. The spacecraft will separate and operate untethered and free-flying, but will operate in controlled proximity/formation flying throughout mission life and will share the same orbital characteristics. The spacecraft are intended to operate in LEO with the orbit parameters shown in Table 6. The satellites 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] 500 km (circular) Inclination [deg] 97.9 degrees Table 7: CubeSat Orbit Parameters 15

Section 25.114(c)(10) Physical Characteristics of Satellites The space vehicles are nano-class satellites (< 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 space vehicles will consist of two 3U CubeSats, which means each CubeSat will have the 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 CubeSat vehicles have been designed primarily as a single-string system using commercial off- the-shelf parts with a mission lifetime of less than one year on-orbit. The mass budget is identical for each of the two elements and is provided in the following table: Component / Subsystem Mass [g] Payload 1300 Spacecraft (Subtotal) 3900 Structure 300 Electrical Power System 1300 Propulsion System 1200 ADCS 400 C&DH 100 Communication 500 Thermal 100 TOTAL 5200 Table 8: CubeSat Mass Budget per Element For propulsion, each of the space vehicles 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, and will be used to demonstrate formation flying and docking. 16

For power generation, each space vehicle 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 Communication 3500 Thermal 400 TOTAL 13500 Table 9: Power Budget per Space Vehicle Section 25.114(c)(12) 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 Fabrication and RF closed loop March 2014- ToL - 19 months testing July 2015 Delivery for Launch Integration July 2015 ToL - 3 months Pre-launch testing of transmitting Aug 2015 ToL - 2 months components 17

Launch Dec 2016 ToL + 0 Release from launch adapter Dec 2016 ToL + 0hr 30min On-orbit check Dec 2016 ToL + 24 hours Start of experiments Jan 2017 ToL + 4 weeks Decommissioning Sept 2017 ToL + 9 months Re-entry Sept 2034 ToL + 17 year Table 10: CubeSat System Major Milestones Section 25.114(d)(1) General Description of Overall System Facilities, Operations and Services The Tyvak CubeSats provide a platform for on-orbit testing of advanced maneuvering and proximity operations 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 vehicles communicate with the Earth stations through a low-rate (19.2 kbps) half-duplex communications link operating in the UHF band. The CubeSat mission 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. Tyvak will manage and perform all operations for both vehicles. The responsibilities of the Irvine MOC will include commanding 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.11 The workstations will serve as 11 TT&C data will be received directly from the spacecraft via UHF link 18

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. Section 25.114(d)(3) 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. Figure 3: CubeSat L-Dipole UHF Antenna Gain Plot The spacecraft 2.4 GHz antenna is a microstrip patch antenna possessing a maximum gain perpendicular to the surface normal to the patch. An antenna gain contour plot from the antenna datasheet is provided below representing the ISM-band ceramic patch 19

Figure 5: CubeSat 2.4 GHz Antenna Gain Plot Section 25.114(d)(14) Orbital Debris Mitigation The CubeSat spacecraft will mitigate orbital debris by the following means: Section 25.114(d)(14)(i) Limiting the amount of debris released during normal operations and the probability of the satellite becoming a source of debris by collisions with small debris or meteoroids that could cause loss of control and prevent post-mission disposal In order to limit the amount of debris generated during normal operations, the CubeSats have 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 Standard and compliance is required for launch using the Poly-Picosatellite Orbital Deployer (“P- POD”) system. The basic geometry of each of the two satellites 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 20

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., 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 500 km, the space vehicle is anticipated to re-enter the atmosphere within 17 year based on lifetime prediction simulations for the current mission epoch (i.e., launch in DEC2016). Section 25.114(d)(14)(ii) Limiting the probability of accidental explosions during and after completion of the mission operations The demonstration of technologies for formation flying and proximity operations are primary mission objectives for the CubeSats. Thus, each 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 vessels will be fully depressurized as a part of the deorbit maneuver process. In addition, the vehicles possess energy storage devices (i.e., Li-ion batteries), which will be left in a nearly discharged state as part of the decommissioning procedure. Section 25.114(d)(14)(iii) 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 CubeSats 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). Although the vehicles 21

do possess propulsive capability for proximity operations demonstration, station keeping, and deorbit, no maneuvers to avoid in-orbit collisions are planned for or anticipated. 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. Section 25.114(d)(14)(iv) Post-mission disposal plans for the space station at end of life The post-mission disposal plan for the CubeSats 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 vehicles. All propellant remaining at end of life will be expended to initiate deorbit, resulting in anticipated atmospheric re-entry of the satellites within 17 years of mission completion based on its mission orbit, vehicle mass, geometry and mission epoch (i.e., launch in DEC2016). 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 Ti or stainless steel, and are not expected to survive reentry. III. CONCLUSION The Experimental Licensing Branch should grant Tyvak’s application for five-year experimental authority to launch and operate two NGSO LEO satellites, which will permit Tyvak to demonstrate and evaluate advanced proximity operations for NASA customers, adding valuable on-orbit performance data for future CubeSat Standard satellites. Tyvak’s experiment will not 22

cause harmful interference to any licensed service. Tyvak will conduct its experiment using low- power transmissions in the 2.4 GHz ISM band and 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. 23


Document Created: 2016-09-19 18:26:16
Document Modified: 2016-09-19 18:26:16
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