The Evolution of the JPL/NASA Iris Cubesat DSN Compatible

Home , Iris (mythology)

Jet Propulsion Laboratory The Evolution of the JPL/NASA California Institute of Technology Iris CubeSat DSN Compatible Transponder

8th ESA International Workshop on Tracking, Telemetry and Command Systems for Space Darmstadt, Germany September 25th, 2019

Presenter: Mazen Shihabi Contributors: Courtney Duncan, Michael Kobayashi, and Sarah Holmes Jet Propulsion Laboratory at the California Institute of Technology Copyright ©2019 California Institute of Technology. Government Sponsorship Acknowledged. Jet Propulsion Laboratory Outline California Institute of Technology

• History of Iris – V 1.0 (INSPIRE Version) – V 2.0 (MarCO Version) – V 2.1 (Artemis -1 “formerly EM-1” Version) • Design, Specifications, Modes and Performance – Hardware, Firmware, and Software – Manufacturing and Testing – Modes – Performance: Downlink, Uplink, SSPA and LNA • Missions used/using Iris – INSPIRE, MarCOs & Artemis-1 (formerly EM-1) • Additional Features being Infused and Future Enhancements

• Not an acronym • Iris – a goddess associated with communication, messages, the rainbow and new endeavors • “Little Sister” to Electra – Electra is a JPL SDR UHF Relay Radio. • Cousin of Cassandra (Cassy) The Iris: an Illuminated Souvenir (1852), upload.wikimedia.org/wikipedia/commons/4/49/1852_Iri – Ground Support Equipment (GSE) s_Illuminated_Souvenir.png. Public Domain that is used for testing Iris 3

Copyright ©2019 California Institute of Technology. Government Sponsorship Acknowledged. Jet Propulsion Laboratory Iris Transponder Evolution History California Institute of Technology • Iris V1.0: To extend CubeSat/SmallSat 10.1 x 10.1 x 4.5 cm deep space capability, JPL introduced the Interplanetary NanoSpacecraft Pathfinder In Relevant Environment (INSPIRE) mission1, coupled with the first-generation of Iris deep-space Iris V1.0 Stack transponder2. 10.1 x 10.1 x 7.5 cm

• Iris V2.0: The radio was further developed, matured, and in 2018 successfully flown onboard Mars Cube One (MarCO), to support InSight’s Iris V2.0 Stack Mars Entry, Descent, and Landing 10.1 x 10.1 x 5.6 cm (EDL)3.

• Iris V2.1: The latest version of Iris includes design updates that support Iris V2.1 Key Specifications4 4 Artemis-1 CubeSats missions . Iris V2.1 Stack

1 A. Klesh et al., “INSPIRE: Interplanetary NanoSpacecraft Pathfinder In Relevant Environment,” in AIAA SPACE Conf. and Expo., San Diego, CA, 2013. 2 C. B. Duncan et al., “Iris Transponder – Communications and Navigation for Deep Space”, in Small Satellite Conf., Logan, UT, 2014. 3 A. Klesh et al., “MarCO: Early Operations of the First CubeSats to Mars,” in Small Satellite Conf., Logan, UT, 2018. 4 M. M. Kobayashi et al., “Iris Deep-Space Transponder for SLS EM-1 CubeSat Secondary Payloads”, IEEE Aerospace and Electronic Systems Magazine, Volume 34, Issue 9, pp 34-44, September 1, 2019. Copyright ©2019 California Institute of Technology. Government Sponsorship Acknowledged. 4 Jet Propulsion Laboratory INSPIRE Iris (V 1.0) California Institute of Technology

Stack of Boards – Modular Design • 10.1 x 10.1 x 4.5 cm CubeSat Paradigm = 0.46U DSN – Compatible X-band Transponder

• 0.45kg, 13 W DC 10.1 x 10.1 x 4.5 cm (Tx/Rx), 0.2 W RF output • 4 slices:

– Digital: Virtex-5 Marina-2 FPGA (no sequential Modem Processor processor) Virtex 5 Power Supply Board – Power Board

– X-Band Exciter X-Band Receiver – X-Band Receiver X-Band Exciter 23 dBm – 1 MHz SPI Iris Prototype Stack (~2013) Interface 5

Copyright ©2019 California Institute of Technology. Government Sponsorship Acknowledged. Jet Propulsion Laboratory MarCO Iris (V 2.0) California Institute of Technology • 10.1 x 10.1 x 7.5 cm = 0.77U: • 1.2kg, 35W DC (Tx/Rx), 4W RF output • Five slices: – Digital: Virtex-6 (Industrial-grade) with embedded CPU (LEON3-FT softcore) 10.1 x 10.1 x 7.5 cm – Power – X-Band Exciter – X-Band Receiver – UHF Receiver – 1 MHz SPI Interface • Radiation Tolerance: 15 krads TID – radiation requirement was 2.9 krads for the 9-month cruise to Mars. • 15-month initial development cycle Copyright ©2019 California Institute of Technology. Government Sponsorship Acknowledged. 6 Jet Propulsion Laboratory Artemis-1 Iris (V2.1) California Institute of Technology

• Radio: 10.1 x 10.1 x 5.6 cm = 0.57 U • 0.86 kg, 34 W DC (Tx/Rx), 4W RF output • Four slices: • Digital: Virtex 6 (Defense-grade) with embedded CPU (SPARC V8: DIGITAL LEON3-FT softcore) running at 50 TRIPLE MHz SSPA POWER • Power Supply Board DUAL 5.6 • Exciter cm EXCITER LNA 10.1 cm • Receiver • 1 MHz SPI Interface RECEIVER • 2-ch LNA: 7 x 4.8 x 1.3 = 44 cc 10.1 cm • 3-ch SSPA: 8.7 x 4.3 x 1.8 = 68 cc • Receiver Noise Figure: 3.5 dB • 62.5 bps to 4 Mbps, CCSDS Deep Space • Doppler, Seq. Ranging, PN Regen, PN Delta DOR • Radiation Tolerance: 23 krads TID • Licensed to Space Dynamics Laboratory (SDL) for manufacturing and sale (POC: [email protected])

Iris Specification Units Iris V1.0 Iris V2.0 Iris V2.1 INSPIRE Version MarCO Version Artemis-1 Version Xilinx Virtex-5 Xilinx Virtex-6 Xilinx Virtex-6 Digital Processor (commercial-grade) (Industrial-grade) (defense-grade) SPARC-Based SPARC-Based Embedded CPU N/A Leon3-FT Softcore Leon3-FT Softcore No. Of Slices 4 5 4 Mass (excl. SSPA/LNA) grams 450 1200 860 Volume (excl. SSPA/LNA) U 0.46 0.77 0.56 32 Mbit NOR-Flash 32 Mbit NOR-Flash 32 Mbit NOR-Flash Memory 128 Mbit Phase-Change Memory chip 16 Mbit SRAM 16 Mbit SRAM for the SPI interface 4 Mbit EDAC SRAM 4 Mbit EDAC SRAM S/C Interface 1 MHz SPI± 1 MHz SPI 1 MHz SPI Bus Power Interface Vdc 6.4 - 8.4 10.5 – 12.3 9.0 – 28.0 DC Power W 13.0 30.0 (including 5-W SSPA) 30.0 (including 5-W SSPA) RF Output Power W 1.0§ 5.0 5.0 Receiver Noise Figure dB 5.0 – 6.0 3.5 3.5 Receiver Sensitivity dBm -135 @ 70 Hz LBW -139 @ 70 Hz LBW -151 @ 20 Hz LBW Downlink Frequencies MHz 8400 - 8500 8400 - 8500 8400 - 8500 Uplink Frequencies MHz 7145 - 7235 7145 - 7235 7145 - 7235 Turn-around Ratio 880/749 880/749 880/749 Uplink Date Rates bps 1,000 62.5 & 1,000 62.5 - 8,000 Downlink Data Rates bps 62.5 - 64,000 62.5 & 1,000 & 8,000 62.5 - 256,000 UHF Receive Freq MHz N/A 390 - 405 N/A UHF Rertun Link Rate bps N/A 8,000 N/A PCM/PSK/PM w/ subcarrier PCM/PSK/PM w/ subcarrier PCM/PSK/PM w/ subcarrier Modulations Waveforms PCM/PM w/ biphase-L, BPSK PCM/PM w/ biphase-L, BPSK PCM/PM w/ biphase-L, BPSK Conv & Reed Solomon Telemetry Encoding Conv & Reed Solomon Turbo 1/6 Turbo ½, 1/3, 1/6 Navigational Support Doppler, SR* Doppler, SR, DDOR† Doppler, SR, DDOR Radiation Tolerance krads N/A 15.0 TID‡ 23.0 TID

±SPI: Serial Peripheral Interface bus †DDOR: Delta Differential One-way Ranging § For the INSPIRE mission, the PA was backed off to 0.2 W to save power ‡TID: Total Ionizing Dose * SR: Sequential Ranging

Iris LNA Modular MIC assembly Iris Transponder Stack • Reduce noise figure by shortening cable Digital Processor length from antenna Xilinx Virtex-6 FPGA • Separate gain cavities Leon3FT Softcore SRAM between LNA and Rx 50MHz Processor TCXO (risk of oscillations) U/L DATA RX PLO Command 50 MHz AGC X-Band LNA Decoder

Tracking X-Band Uplink VVA ADC X- Loops D/L DATA 71457145 ––72357235 MHz MHzk Pre-Select Image SAW Filter X-130-130dBmdBm toto -70 -70dBm dBmk Reject X-band Receiver

I-DAC Iris SSPA X-Band SSPA X-Band Exciter

DDS DDS Telemetry X BandX-X Downlink DAC Generator Modulator 8400 –- -8500 MHz Isolator TX PLO DDS Input 3.8 4 W BOL Filter

Modular MIC assembly Q-DAC • Provide superior heat dissipation path to Modular stacked-slice assembly structure/radiator • Chip-and-wire assy to • Superheterodyne receiver with single-downconversion stage to 112.5 MHz IF reduce losses for • Digitally closed tracking loops (carrier, subcarrier, symbol) higher efficiency • Direct Digital Synthesis (DDS) reference for downlink carrier Doppler tracking • Baseband telemetry modulated direct at X-band • Embedded softcore processor (Leon3-FT) for configuration and protocol mgmt

Copyright ©2019 California Institute of Technology. Government Sponsorship Acknowledged. 9 Jet Propulsion Laboratory Iris Hardware Photos California Institute of Technology Digital Processor (RaDix) Power Supply Board DDS Virtex-6 DAC Flyback FPGA Conv

1V SRAM Reg FLASH Switchers

X-band Exciter X-band Receiver Tx-Out IF I/Q Amps Mixer Rx-PLL SAW Img-Rej Filters Mixer VVAs TCXO Tx-PLL Rx-In

• Single-threaded Internal • SPARC V8 instruction set (same as used on Interrupt UST1) Reset SRAM EDAC Error – UST stands for the Universal Space Transponder Handler which is the next generation SDR JPL INIT transponder that can support simultaneous CDH Peek multiband operations with data rates up to 37.5 Cmd Handler Mbps RX and 300 Mbps TX. Execute C&DH CMD – This allows a single radio to support all the DMA Complete direct-to-Earth and relay communication Handler DMA requirements for even complex mission N DONE / scenarios, reducing the total cost, mass, and READ power. Y Y Traps • Softcore LEON3-FT processor Tx Data • SRAM: 2 MB total Trap Handlers – Program size: Program size: ~100 kB • Running at 50 MHz

1 M. Pugh et al., “The Universal Space Transponder: A Next Generation Software Defined Radio”, IEEE AIAA Conference, Big Sky, Montana, USA, 4-11 March 2017.

Copyright ©2019 California Institute of Technology. Government Sponsorship Acknowledged. 11 Jet Propulsion Laboratory California Institute of Technology Available Modes and Some Configuration Parameters

Configuration Mode Receiver Transmitter Ranging DDOR Coherency Available Settings Parameter LNA, 62.5 bps, 62.5, 125, 250, 500, X-Band Receive-Only ------PCM/PSK/PM 16 Uplink Data Rate 1000, 2000, 4000, kHz sine 8000 bps SSPA, 62.5, 125, 250, 500, 62.5 bps, 1000, 2000, 4000, X-Band Transmit-Only -- Off Off Off PCM/BPSK/PM 25 Downlink Data Rate 8000, 16000, 32000, kHz square 64000, 128000, 256000 bps LNA, SSPA, X-Band 62.5 bps, 62.5 bps, Downlink Data Turbo 1/2, Turbo 1/3, Off Off On Transmit/Receive PCM/PSK/PM 16 PCM/BPSK/PM 25 Encoding Turbo 1/6 kHz sine kHz square AOS Frame Length 8920 or 1784 bits LNA, 62.5 bps, Ranging – No Data SSPA On Off On Subcarrier: PCM/PSK/PM 16 0 to 138 degrees Exciter Mod Index kHz sine Direct carrier: DDOR – No Data -- SSPA Off On Off 0 to 135 degrees Additional commands may be used to configure the Iris into modes not defined above. Other parameters include subcarrier Other Modes For example, if Ranging with Data is desired, frequency, coherency, antenna selection, etc. command Iris to Tx/Rx mode, and then send a command to enable ranging. Note that the configurations in the modes above are the default settings, and can be changed with additional commands.

• 1 EDU, 6 Flight Units manufactured and tested at Space Dynamics Laboratory – Take the JPL designs and fabricate the boards/chassis – Test and verify functionality – Assemble unit and perform ATP – Ship to JPL for final RF tests and delivery to mission • Additional testing performed on EDU – Vibe testing on Iris, SSPA and LNA (SDL) – EMC Testing

ß Iris at EMC lab at JPL

Iris at SDL on Vibe Plate à

• Downlink Bit rates from 62.5 bps to 256 kbps • Experimentally achieved 6.25 Msps • Output Power of 36 dBm • Compatible with DSN hardware (Turbo ½, 1/3, and 1/6) at all data rates • Phase Noise: • -72.7 dBc/Hz @ 1 kHz, -125.1 dBc/Hz @ 1 MHz • Spurs/Harmonics are below -30 dBc

Spurs: 260KHz @ -50 dBc

Iris V2.1 measured X-band Downlink Carrier-Only Iris V2.1 measured X-band Downlink Spectrum of PN Spectrum. bit sequence in RC mode with Biphase-1 at 6.25 Msps

• Carrier Tracking Threshold from -146 to -155 dBm depending on LBW • Command threshold for 62.5 bps at -141 dBm (DTF-21) • Data rates selectable from 62.5 bps to 8 kbps

Iris V2.1 measured carrier tracking threshold at Iris V 2.1 measured receiver BERs at ambient on ambient. 16-kHz sinewave subcarrier. The predict curve includes 3 dB of implementation loss from the tracking loop.

• SSPA LNA – Output power: 36 dBm • 3.1 dB Noise Figure at 25C – Gain: 58 dB • Gain: 46 dB • – Efficiency: 29% Power Draw: 350 mW – 14 W Power Consumption

LNA (Top) and SSPA (Bottom) RF paths.

INSPIRE Interplanetary Nano Spacecraft Pathfinder in a Relevant Environment (2014)

INSPIRE Mission Concept

Up/Downlink Up/Downlink Provide reduced size/cost components to enable a new class of interplanetary Crosslink explorers Lithium UHF INSPIRE-A INSPIRE-B INSPIRE-A INSPIRE-B INSPIRE was funded by NASA's Planetary Science Division (PSD) as a collaboration between the Jet Propulsion Laboratory (JPL), California Polytechnic-San Luis Obispo (CalPoly), Goldstone-Apple Valley Radio Telescope (GAVRT), Massachusetts Institute of Technology (MIT), University of California – Los Angeles (UCLA), University of Michigan (UMich), and University of Texas-Austin (UTexas).

(Did not Launch; before a flight could be arranged the goals of INSPIRE became obsolete)

Copyright ©2019 California Institute of Technology. Government Sponsorship Acknowledged. 17 Jet Propulsion Laboratory MarCO Mission Overview (2018) California Institute of Technology • Provide “real-time” data relay during EDL of InSight to Mars • Bent-pipe: – UHF receive of EDL data – X-band transmit Direct-to-Earth • Two MarCOs for redundancy • Tech Demo • First deep space CubeSats • MarCOs launched with InSight but traveled independently to Mars • Successfully completed EDL with zero data loss • MarCO enabled quick reception of InSight’s first image on Mars (on the right) – Also, an image of Mars & the reflect array HGA with the feed showing (on the left).

Copyright ©2019 California Institute of Technology. Government Sponsorship Acknowledged. Jet Propulsion Laboratory 6 Artmeis-1 CubeSats Using Iris California Institute of Technology (2020~) • 7 Artemis-1 CubeSats have baselined to use Iris for basic telecom & navigations. • For the 6 NASA missions, JPL managed the contract with SDL LunaH-Map • ArgoMoon Iris was purchased directly by Agotec from SDL. • They share common Telecom Hardware (Iris Radio, LNA/SSPA, Rx/Tx antennas) with different science goals & target destinations. Lunar IceCube

Low Noise Amplifier Rx LGA (LNA) Lunar Flashlight

Tx LGA Iris Radio CuSP

Solid State Power Amplifier (SSPA) Tx MGA Deep Space Network (DSN) BioSentinel Artemis-1 CubeSat Telecom Hardware Using Iris

• ArgoMoon is an Italian 6U CubeSat to be injected in a high elliptic – high apogee orbit. Several Moon fly-bys and imaging of the surface will be performed. ArgoMoon NEA Scout Copyright ©2019 California Institute of Technology. Government Sponsorship Acknowledged. 19 Jet Propulsion Laboratory California Institute of Technology Additional Features being Infused to V 2.1

• Over the Air Programmability • Pseudo-Noise (PN) Delta DOR1 • PN Regenerative Ranging2

1 Z. Towfic, T. Voss, M. Shihabi, and J. Border, “X-band PN Delta DOR Signal Design and Implementation on the JPL Iris Transponder,” IEEE AIAA Conference, Big Sky, Montana, USA, 2-9 March 2019. 2 K. Angkasa et al., “Regenerative Ranging for JPL Software-Defined Radios”, IEEE Aerospace and Electronic Systems Magazine, Volume 34, Issue 9, pp 46-55, September 1, 2019.

• Other frequency bands (UHF, S, Ka)

• Reliable space-link protocols for relay functionality (CCSDS Prox-1 protocol) TRL-4 Ka- (and S-) Band exciter • Delay/Disruption Tolerant Networking

• Higher downlink rates beyond 2Mbps

• Low-Density Parity-Check (LDCP) code TRL-4 UHF • SpaceWire interface for high-rate data exciter transfers to S/C C&DH unit

• Higher efficiency SSPA – Lower DC power in general