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FormoSat-7 / COSMIC-2 (Constellation Observing System for Meteorology, Ionosphere and Climate)

Overview    Spacecraft    Launch    Sensor Complement   Ground Segment   References

The FormoSat-7 / COSMIC-2 constellation (simply known as FS-7/C-2) is an international collaboration between Taiwan (NSPO) and the United States (NOAA) that will use a constellation of 12 remote sensing microsatellites to collect atmospheric data for weather prediction and for ionosphere, climate and gravity research. NSPO/NARL (National Space Organization/National Applied Research Laboratories) is the designated representative for Taiwan and NOAA (National Oceanic and Atmospheric Administration) is the designated representative for the U.S. Note: NARL is also referred to as NARLabs.

FormoSat-7 / COSMIC-2 is a follow-on mission to the FormoSat-3 / COSMIC mission to meet the RO (Radio Occultation) data continuity requirements of the user community. NOAA and NSPO intend to provide a high-reliability next generation satellite system.

The overall objective of FS-7/C-2 is to advance the capabilities of regional and global weather prediction (including severe weather prediction). The goal is to collect a large amount of atmospheric and ionospheric data primarily for operational weather forecasting and space weather monitoring as well as meteorological, climate, ionospheric, and geodetic research. It is expected to be a much improved constellation system consisting of a new constellation of 12 satellites for an operation mission.

The primary mission payload will be a TriG (third generation) GNSS-RO receiver and will collect more soundings per receiver by adding European Galileo system and Russia's GLONASS (Global Navigation Satellite System) tracking capability, which will produce a significantly higher spatial and temporal density of profiles. These will be much more useful for weather prediction models and also for the severe weather forecasting including typhoons and hurricane, as well as for the related research in the fields of meteorology, ionosphere and climate. 1) 2) 3) 4) 5) 6) 7) 8) 9) 10) 11) 12) 13) 14) 15) 16) 17) 18)

The constellation is planned to be comprised of 6 satellites at 72º inclination, and 6 satellites at 24º inclination, which will enhance observations in the equatorial region over what is currently being collected with FormoSat-3 / COSMIC. This constellation configuration was chosen because it provides the most uniform global coverage, as shown in Figure 1. Figure 1 shows the global sounding (data point) distribution versus the various orbital inclinations that were considered. 19) 20) 21)

This constellation will produce 8,000+ sounding profiles per day, compared to the approximate 2,000 soundings per day currently produced by FormoSat-3 / COSMIC due to the ability of FS-7/C-2 to track three navigation systems' signals (GPS, GLONASS, and Galileo) versus the ability of FormoSat-3 / COSMIC to track only one (GPS).


Figure 1: Potential satellite inclinations vs. Global sounding coverage for FormoSat-7/COSMIC-2 (image credit: UCAR)


Figure 2: Comparison of sounding distributions for FormoSat-3 / COSMIC and FormoSat-7 / COSMIC-2 (image credit: UCAR)


Responsibilities of FormoSat-7 /COSMIC-2 partner organizations:

NSPO shall be responsible for:

• Acquisition, management, and deployment of satellites constellation

• Development and management of mission operations

• Modification and operations of the SOCC (Satellite Operations Command and Control) station and Taiwan's TT&C station

• Acquisition and management of the Taiwan data processing center.

• Acquisition and management of the scientific payloads for second six satellites.

NOAA shall be responsible for:

• Acquisition and management of the GNSS-RO mission payload

• Overall management of the data analysis, application, and distribution segment

• Acquisition and management of the launch vehicle system

• Arrangement for and oversight of the remote ground receiving stations

• Acquisition and management of the scientific payloads for the first six satellites

• Acquisition and management of the data processing center in the U.S.

NOAA and NSPO shall be jointly responsible for the acquisition and management of the scientific payloads.

• Taiwan to provide: 12 spacecraft and integration of payload onto spacecraft, mission operations center, command & control station, and limited data recovery

• NASA providing: NRE (Non Recurring Engineering) for new sensor design

• USAF (US Air Force) to provide: Launch services for all 12 spacecraft and provide 12 AF payloads (2 per spacecraft) for 24º launch orbit

• NOAA to provide: 12 sensors, data recovery stations, command and control stations, payload data processing, and archival.

Table 1: Partnership responsibilities of the FormoSat-7/COSMIC-2 mission (Ref. 13)


Figure 3: Collaborative framework of the FormoSat-7(COSMIC-2 joint mission (image credit: NSPO, NOAA) 22) 23)


FormoSat-7 / COSMIC-2 mission

FormoSat-3 / COSMIC mission


- Establish an operational mission for near real-time numerical weather prediction
- 8,000 (threshold) profiles per day (the goal is 10,000)

- Demonstration of near real-time numerical weather prediction
- 1,600~1,800 profiles per day


- NSPO will provide 12 satellites for the joint mission and a spare satellite in space depending on the launch vehicle capability.
- NSPO will integrate new GNSS P/L provided by JPL & perform P/L system Integration & Test at NSPO

- NSPO defined system requirements
- NSPO & Orbital designed the spacecraft
- UCAR provided the P/L suite
- EDU and FM1 I&T at Orbital
- FM2 to FM6 I&T at NSPO

Mission P/L capabilities

GPS / GALILEO / GLONASS tracking capabilities

GPS tracking capability

Launch vehicle provision

NOAA will provide 2 dedicated launches into selected orbits and inclinations

Use the US Air Force Minotaur L/V through UCAR's acquisition

Ground system

NOAA's strategy is to use U.S., European, Asian, and polar ground networks

Use of the USN ground stations for the first 2 years, and then service provision by NOAA's ground stations for the following 3~5 years


High degree of automated ground system for a minimum of a 12 satellite constellation

6 satellite constellation operations

Data processing

- TACC (Taiwan Analysis Center for COSMIC) Upgrade
- CDAAC Upgrade

TACC & CDAAC Implementation
GPS-ARC Initiation

Table 2: Comparison of functions allocated in FormoSat-7(COSMIC-2 and FormoSat-3/COSMIC constellations (Ref. 2)


Figure 4: System architecture of FS-7/C-2 (image credit: NSPO, NOAA, Ref. 27)

The project plan is to launch 2 rockets (Falcon-9) with 6 satellites on each rocket. They will be launched and then positioned into their final orbits (nominally 720 km altitude for the 72º inclination orbit and 520 km altitude for the 24º inclination orbit). 24)

The original FormoSat-3 / COSMIC mission had an operational concept of allowing for one data downlink per orbit. The plan for FS-7/C-2 is to allow for 2 data downlinks per orbit, which will considerably reduce the data latency. Consequently, FS-7/C-2 will require more satellite ground stations for receiving the data. As with FormoSat-3 / COSMIC, the data collected by FS-7/C-2 will be downlinked to the tracking station, then transmitted to the COSMIC processing center CDAAC (COSMIC Data Analysis and Archive Center) in Boulder, CO, as well as to the Taiwan processing center TACC (Taiwan Analysis Center for COSMIC) for processing.

The processed products will then be provided to the NOAA GTS (Global Transmission System) for distribution to the worldwide weather prediction centers. Command and control for the FS-7/C-2 constellation will continue to be provided by the NSPO SOCC (Satellite Operations Control Center). Payload operational configurations will continue to be managed by a joint effort between UCAR (University Corporation for Atmospheric Research) and JPL (Jet Propulsion Laboratory) with NOAA and NSPO concurrence for updates and changes.


First launch of 6 spacecraft

Second launch of 6 spacecraft

Mission objectives

To be achieved after FOC (Full Operational Capability):
8,000+ atmospheric sounding profiles per day
45 minute data latency

Mission constellation

6 satellites (each of 215 kg wet estimated mass)

6 (or 7) satellites (each of 215 kg wet estimated mass)

Mission orbit

Inclination 24º, Parking altitude = 720 km
Mission altitude of ~ 520-550 km, circular orbit

Inclination 72º, Parking altitude 520 km
Mission altitude of ~ 720 km, circular orbit

GNSS RO payload

TGRS (Tri-band GNSS ReceiverSystem), provided by NOAA/JPL

Science payload

- 2 band Radio Beacon scintillation instrument
- IVM (Ion Velocity Meter) instrument

Taiwan furnished payload

Launch vehicle

Falcon Heavy (rideshare) carrying 6 satellites, ESPA ring

Falcon-9 carrying 7 satellites (including 1 spare)

Launch schedule (expected)

Q2 2016

Q3 2018

Max daily average data latency

45 minutes neutral atmospheric data, 30 minutes ionospheric data

Communication architecture

SFTP (Scalable Fault-Tolerant Protocol) multicast via VPN (Virtual Personal Network) Internet

Ground stations

There shall be sufficient ground stations to meet the data latency requirement

Primary Data Processing Centers

US-DPC (UCAR) and Taiwan-DPC (TACC)

Mission duration

10 years

Table 3: Baseline mission requirements of FS-7/C-2 (Ref. 14)


Status of the project development:

• December 2015: President Ma Ying-jeou of Taiwan, together with Premier Mao Chi-kuo, the Minister of Science and Technology and other dignitaries, visited the National Space Organization (NSPO) recently, where they were invited to view progress on the assembly and testing of the FORMOSAT-5 AND FORMOSAT-7 satellites. During the visit, President Ma Ying-jeou and Premier Mao Chi-kuo observed a planned spacecraft solar array deployment test being performed by NSPO on one of the six FORMOSAT-7 spacecraft, with support from SSTL. 25)

- Three of the FORMOSAT-7 spacecraft have already completed their integration and test campaign in Taiwan, and all six spacecraft are scheduled to be ready for their FRR (Flight Readiness Review) in the first-half of 2016, ahead of their launch later in the year.

• May 1, 2015: SSTL has delivered the first spacecraft for the FormoSat-7/COSMIC-2 weather forecasting constellation to NSPO (National Space Organization) in Taiwan, where it has successfully passed a series of systems checks. 26)
The first shipment of satellites (FM1 and FM3) arrived at NSPO on March 24, 2015. Note: the FM1 is also referred to as the PFM (Proto-Flight Model). 27) 28)

• March 2015: Amendment No.1 to the IA#1 through AIT/TECRO to update from 6-Satellite/1-Launch to 12-Satellite/2-Launch has been in work (Ref. 27).

• December 2014: SSTL completed PFM I&T (Integration and Test)) at SSTL UK (Ref. 27).


Figure 5: SSTL spacecraft bus schedule overview (image credit: SSTL, NARLabs, Ref. 27)

• The USAF and JPL held the Pre-Ship Review (PSR) for the TGRS units #2-6 on March 24, 2015. The PSR was successful and all sensors were shipped to Taiwan on April 3, 2015.

• Oct. 2014: All first flight units for TGRS, IVM, and RF Beacon were delivered to SSTL and successfully powered through the spacecraft (Ref. 18).

• TGRS (Tri-band GNSS Receiver System)

- Software updates enabling loads through spacecraft

- Units #2-4 completed and in storage

- Completion of development, I&T, and software efforts for #2-6 through UCAR – JPL contract

- TGRS Pre-Ship Review (PSR) for #2-6 will occur Oct/Nov 2014.

• IVM (Ion Velocity Meter)

- All parts are in inventory

- Unit #5 integrated and ready for test

- Test Readiness Review (TRR) was held on 17 September, 2014

- Delivery of units #2-6 expected 15 Jan 2015.

• RF Beacon

- Completed Beacon Electronics Unit (BEU) / Antenna Unit (AU) combined checkout

- Completion of development and I&T efforts for #2-6 through UCAR - SRI contract

- Delivery of RF Beacon Unit #2 expected March 2015.

• On Oct. 22, 2014, the NOAA-UCAR System Requirements Review (SRR) for the DPC (Data Processing Center) segment was successfully completed (Ref. 28).

• In FY 2014, the COSMIC-2 program became an officially NOAA funded program (Ref. 18).

• December 2013: Joint Team conducted Joint Program PDR-B at NSPO (Ref. 27).

• November 2013: NSPO conducted the Spacecraft CDR (Critical Design Review) at NSPO Taiwan (Ref. 27).

• December 2012: Taiwan & U.S. signed the IA#1 (Implementing Arrangement #1).

• The SRR (System Requirements Review) is scheduled for April 2011, the PDR (Preliminary Design Review) for June 2011, and the CDR (Critical Design Review) for September 2011.

• The Joint Program Office held the FDR (Feasibility Design Review) in May 2010 and the MDR (Mission Definition Review) in August 2010.

• The U.S.-Taiwan agreement that is the authorizing document for the FormoSat-7 COSMIC-2 program was signed by both parties in May 2010.


FormoSat-7 design

FormoSat-3 design

Spacecraft bus reliability

>0.66 for 5 years

>0.68 for 2 years

Spacecraft mass

~277.8 kg (wet)

61 kg (w/ propellant)

Attitude control performance

3-axis linear control
Roll/Yaw/Pitch:±1º (3σ)
Attitude knowledge: better than 0.05º (3σ), all axis GPS bus receiver x 1

3-axis nonlinear control
Roll/Yaw: ±5º (1σ), Pitch: ±2º (1σ)
GPS bus receiver PL x 1

Data storage

Bus: > 256 MByte
Science: >2 Gbit

128 MByte

Avionics architecture

Centralized architecture, radiation - hardness

Distributed architecture, (multiple avionics boxes)

Electrical power

10 % power margin
Lithium-ion battery
Voltage based algorithm

10 % power margin
Ni-H2 battery
dMdC charging algorithm

Payload interface

Mission PL: TriG
Science PL: IVM & RF beacon

Primary PL: GOX
Secondary PL: TIP, TBB

Table 4: FormoSat-7 enhanced satellite design




On Sept. 6, 2012, NSPO awarded a contract to SSTL (Surrey Satellite Technology Ltd., UK) to built 12 minisatellites for the FormoSat-7/COSMIC-2 program. The spacecraft bus contract kick-off ceremony was held at NSPO (National Space Organization) and co-chaired by Dr. Guey-Shin Chang, Director General of NSPO, and Sir Martin Sweeting, Executive Chairman of SSTL. 29) 30)

The first phase is to deploy 6 satellites, each carrying an advanced GNSS receiver, to low-inclination-angle orbits. The launch is targeted in 2016.

Under the contract, SSTL will design and manufacture satellites for the FormoSat-7 program at its facilities in Guildford, UK, with the payloads being produced by NSPO's partners in the USA. NSPO will be responsible for the integration of the majority of the spacecraft at its facilities in Taiwan. The spacecraft design phase is already underway and SSTL is tailoring a new 200 kg platform to the mission requirements.


Figure 6: Spacecraft external layout viewed from the +x direction (image credit: SSTL, NARLabs)

Spacecraft design: The FS7/C-2 constellation will need to use the same mission control and mission operations ground system network as is being used for the FORMOSAT-3 system. The heritage baseline employed for the spacecraft is the SSTL-150 bus, which has been used on numerous previous missions. This configuration allows a more conventional design to be accommodated, without the need for extensive mass optimization and miniaturization. The avionics set provides a large degree of redundancy commensurate with mission lifetimes beyond 5 years. This bus is modified in some areas according to mission specific requirements. 31)


Figure 7: Illustration of the stowed spacecraft bus (image credit: SSTL, NARLabs)

The propulsion system is based on heritage space components, and uses a monopropellant hydrazine system. Four thrusters are employed in order to permit spacecraft attitude control during propulsive maneuvers. Larger reaction wheels are employed to provide adequate control authority. Finally, star cameras are included to improve the attitude knowledge in support of the scientific payloads. One efficiency saving has been implemented by sharing capabilities cross the redundant OBCs (On-Board Computers) and redundant star camera processors, resulting in the need for just three computers. The resulting spacecraft avionics block diagram is shown in Figure 8.


Figure 8: FormoSat-7 spacecraft system block diagram (image credit: SSTL, NSPO)


Figure 9: Illustration of the FormoSat-7/COSMIC-2 spacecraft and its sensors (image credit: SSTL)

Note: TGRS (TriG-GNSS) = TriG GNSS Radio occultation System 32)

IVM (Ion Velocity Meter)

Spacecraft size (stowed)

1000 mm x 1250 mm x 1250 mm

Launch mass (wet)

277.8 kg

Total power / OAP ( Orbit Average Power)

229.8 W (orbit average), battery capacity >22.5 Ahr

Attitude control

3-axis linear control
Pointing knowledge <0.07º (3σ)
Pointing control < 1º (3σ)

Orbit control (propulsion)

Hydrazine monopropellant system, ~141 m/s


GPS receiver


S-band TM/TC, 32 kbit/s uplink, up to 2 Mbit/s downlink

Design life

5 years, > 66%


> 95%

Launch compatibility

EELV (ESPA Grande Adaptor)

Payload support

>2 Gbit data storage, 40 kg mass, 95 W OAP (Orbit Average Power)

Design Features

- Dual redundant avionics
- Batch launch compatible
- Constellation compatible

Table 5: Spacecraft bus key design features

RF communications: Use of COM DEV's S-band TT&C transponder, which was developed and certified under ESA's ARTES 3-4 program. The transponder combines the latest gallium nitride power amplifier technology with a flexible SDR (Software Defined Radio) system in a very light-weight, compact and efficient design, using commercially available components. The SDR is implemented on a field programmable gate array (FPGA), allowing the use of different modulation schemes and data rates to provide a flexible approach for different missions and mission phases. The transponder has previously been flown exactView-1 and is currently preparing to fly on a forthcoming M3MSat (Maritime Monitoring and Messaging Microsatellite) launch of Canada. 33)


Figure 10: Photo of the COM DEV TT&C transponder (image credit: COM DEV)


Figure 11: PFM solar array undergoing deployment test at SSTL UK in Nov. 2014 (image credit: SSTL, NARLabs)


Launch: The FormoSat-7/COSMIC-2 program uses 2 launches of 6 satellites each which are scheduled for October 2016 and 2018, respectively. 34)

• The USAF awarded a launch vehicle contract to SpaceX in January 2013, to launch FormoSat-7/COSMIC-2 on the STP-2 (Space Test Program-2) mission Falcon Heavy launch vehicle.

• Falcon Heavy in development – new features materializing. A test flight of the SpaceX Falcon Heavy is planned for the spring of 2016.

- Landing legs added

- Side cores same length as center core (were longer)

- Focus is on upcoming Falcon 9 flights/cert.


Figure 12: Mounting configuration for the EELV (ESPA Grande Adaptor) launch option (image credit: SSTL, NOAA, NSPO)

EELV-Grande launch option: This launch configuration provides a much more generous mass and volume allocation for the platform avionics. A more conventional design can be accommodated in this selection, without the need for extensive mass optimization and miniaturization.

The secondary payloads on this flight are:

• OTB (Orbital Test Bed) minisatellite mission of SST-US (Surrey Satellite Technology US LLC).

• DSX (Demonstration and Science Experiments) mission of AFRL

• GPIM (Green Propellant Infusion Mission), a demonstration microsatellite of NASA. 35)

• FalconSat-7, a 3U CubeSat mission developed by the Cadets of the U.S. Air Force Academy (USAFA) at Colorado Springs, CO.

• NPSat-1 (Naval Postgraduate School Satellite-1) of the Naval Postgraduate School, Monterey, CA

• OCULUS-ASR (OCULUS-Attitude and Shape Recognition), a microsatellite of MTU (Michigan Technological University), Houghton, MI, USA.

• Prox-1, a microsatellite of SSDL (Space Systems Design Laboratory) at Georgia Tech.

• LightSail-B of the Planetary Society, a nanosatellite (3U CubeSat) will be deployed from the parent satellite Prox-1.

• etc.


• First launch: Six FormoSat-7 satellites will be positioned in a low inclination orbit at a nominal altitude of ~520-550 km with an inclination of 24º. The parking orbit of 720 km. Through constellation deployment, they will be placed into 6 orbital planes with 60º separation.

• Second launch: Six FormoSat-7 satellites will be positioned in a high inclination orbit at a nominal altitude of ~720 km with an inclination of 72º. Through constellation deployment, they will be placed into 6 orbital planes with 30º separation.


Figure 13: Illustration of the FS-7/C-2 constellation orbits (image credit: NSPO, NOAA)


Figure 14: Artist's rendition of a deployed FormoSat-7/COSMIC-2 spacecraft in orbit (image credit: SSTL)



Sensor complement: (TGRS, IVM, RF Beacon)

Initially in the project, the TGRS (Tri-band GNSS Receiver System) was referred to as TriG-RO [Tri-GNSS (GPS+ Galileo+GLONASS) Radio Occultation receiver].

TGRS /Tri-band GNSS Receiver System)

NASA/JPL (Jet Propulsion Laboratory) is developing a next-generation GNSS space science receiver, the TriG receiver. The receiver will upgrade the capabilities offered by the current state of the art BlackJack/IGOR GPS science receivers in order to meet NASA's decadal survey recommendations. This includes the ability to track not only GPS, but additional GNSS signals, including Galileo, CDMA GLONASS and Compass.

Most of the low level signal processing will be done inside multiple reconfigurable FPGAs, which can be updated post-launch to track new in-band GNSS signals as they become available. TriG will greatly increase the amount and quality of data by employing digital beamforming to direct multiple simultaneous high-gain beams at GNSS satellites.

With this new architecture and the availability of Galileo, GLONASS and Compass signals, many more occultations will be observed each day. The TriG receiver will have two processors, one for performing POD (Precise Orbit Determination), and the other dedicated to occultation and other science applications. The science processor will run Linux and can be programmed by scientists in a high-level scripting language, putting the scientist in the driver's seat when it comes to onboard processing of science data. 36) 37)

TriG technology demonstration: As part of the NASA Instrument Incubator program, JPL developed a prototype of the TriG receiver, namely TOGA (Time-shifted, Orthometric, GNSS Array), and demonstrated dual processor coupling, multi-frequency beamforming, and L5 tracking of both Galileo, GPS, and WAAS L5 signals. 38)

The TriG receiver is a NASA funded instrument. The hardware development is at Moog Broad Reach (formerly Broad Reach Engineering), the software development and complete end-to-end testing is at JPL. 39) 40) 41) 42) 43) 44)

• TriG includes the POD (Precise Orbit Determination) and RO (Radio Occultation) functionalities other than the capability of tracking existing and future GNSS signals. TriG receives all L-band GNSS signals (GPS, Galileo, GLONASS, Compass) and DORIS.

- TriG has separate science processor and the navigation processor (dual processor architecture)

- TriG possesses higher SNR compared to its previous generation receivers

- TriG is tolerant to a total ionizing dose of 40 kRad.

• TriG design is based upon heritage derived from the BlackJack/IGOR receivers that flew on numerous missions with successful operation.

• NASA is scheduled to receive the "in place delivery" of the first fully tested EM (Engineering Model) by early summer of 2013.

• A second EM (with higher Navigation processor throughput capability) is also being built for NOAA in support of the COSMIC -2 program. The NOAA EM is upgraded to allow two additional RF down-converter cards and up to 16 antenna inputs to include surface reflection sensing capability and receiving DORIS signal.

Instrument mass, power

~6 kg, 50 W

Instrument volume

30 cm x 30 cm x 20 cm

Antenna inputs

8 channels

GNSS Real-time Navigation Processor

- Acquires and tracks GNSS signals
– Sets realtime clock
– Generates position, velocity and time
– Outputs time-tagged phase/range/SNR
– Sends navigation data to Science Processor

Science Processor

– Schedules Ionospheric/Atmospheric occultation profiles
– Extracts 1 ms phase/range/amp
– Formats observables

Data volume

200 MByte/day

Table 6: Preliminary overview of TGRS instrument parameters

For a full-up occultation receiver the spacecraft would also have to accommodate a fore and an aft occultation antenna (2.5 kg each) and a POD antenna (1 kg) with their attendant fields of view, and cables between the antennas and the receiver.


Figure 15: Architecture of the TriG instrument (image credit: JPL)


Figure 16: Conceptual view of the TriG GNSS-RO instrument elements (image credit: JPL)

RFDC = RF-downconversion array


TGRS performance features: 45)

• Support for GPS CA, L1 and L2 Semi-Codeless, L2C, and L5

• Supports from 1 to 16 antennas

• Supports POD (Precision Orbit Determination), cm level positioning, mm/sec level velocity

• Supports RO (Radio Occultation) science for weather and climatology

• Supports Reflections science applications (in development).

The TGRS receiver requires more capable antennas than those flown on missions such as COSMIC. To maximize the number of ionospheric and atmospheric profiles, the TGRS receiver will be capable of tracking legacy and new GPS signals such as L5, L2C and L1C; GLONASS CDMA and Galileo E1 and E5a. 46)


Figure 17: Photo of the TriG instrument with seven 3U slot cPCI chassis (image credit: Moog Broad Reach)

Navigation Processor Features

RO-Science Processor Features

• PPC603r Processing Platform using RogueOS

• 128 kB of System EEPROM (with TMR)

• 1 GB of System NAND Flash (with TMR)

• 256 MB of System SDRAM (with EDAC)

• 384 MB of Sample SDRAM (no EDAC)

• On-orbit Reconfigurable DSP FPGA

• Spacecraft communication

- 3 RS422 UARTs

- 2 SpaceWire Ports

- 4 RS422 pulse/s outputs, 1 LVDS pulse/s output

• Ethernet interface for GSE communication during code development

•IBM750FX Processing Platform using Linux OS

• 128 kB of System EEPROM (with TMR)

• 1GB of System NAND Flash (with TMR)

• 256 MB of System SDRAM (with EDAC)

• 1GB of Buffer SDRAM (no EDAC)

• Spacecraft communication

- 3 RS422 UARTs

- 2 SpaceWire Ports

- 4 RS422 pulse/s outputs, 1 LVDS pulse/s output (generated by RO-Science DSP)

• PCI interface for backplane communication with RO-Science DSP board

• Ethernet interface for GSE communication during code development

Table 7: Summary of dual processor architecture


Figure 18: Block diagram of the TGRS instrument (image credit: NASA/JPL, Garth Franklin)

In 2013, Moog Broad Reach completed the TriG HW development in collaboration with NASA/JPL and has delivered the EM (Engineering Model) HW platform to Jet Propulsion Laboratory. 47)


3D printed antenna arrays:

In 2014, RedEye, a Stratasys Company and leading provider of 3D printing services, partnered with NASA/JPL to 3D print 30 antenna array supports for the FormoSat-7 /COSMIC-2 satellite mission. This is the first time, 3D printed parts will function externally in outer space. The antenna arrays will capture atmospheric and ionospheric data to help improve weather prediction models and advance meteorological research on Earth. 48) 49)

A standard antenna array support design is traditionally machined out of astroquartz, an advanced composite material certified for outer space. Building custom antenna arrays out of astroquartz is time consuming and expensive because of overall manufacturing process costs (vacuum forming over a custom mold) and lack of adjustability (copper sheets are permanently glued between layers of astroquartz).

In order to keep the project on time and on budget, JPL needed an alternative method. They turned to RedEye to produce 3D printed parts that could handle the complex array designs and also be strong enough to withstand the demands of outer space. RedEye built the custom-designed parts using FDM (Fused Deposition Modeling) and durable ULTEM 9085 material, a thermoplastic that has similar strength to metals like aluminum but weighs much less.

Using FDM for a project like this has never been done before and it demonstrates how 3D printing is revolutionizing the manufacturing industry. While ULTEM 9085 has been well-vetted in the aerospace industry and is flammability rated by the FAA (Federal Aviation Administration), it has not previously been used or tested for an exterior application in space. Therefore, in addition to standard functional testing (i.e. antenna beam pattern, efficiency, and impedance match), FDM ULTEM 9085 and the parts had to go through further testing in order to meet NASA class B/B1 flight hardware requirements. Some of these tests included susceptibility to UV radiation, susceptibility to atomic oxygen, outgassing, thermal properties tests, vibration / acoustic loads standard to the launch rocket etc.

The ULTEM 9085's properties met all required qualification tests. To protect the antenna array supports against oxygen atoms and ultraviolet radiation, a layer of NASA's S13G protective paint was applied to the parts.


Figure 19: The complex arrays are made of ULTEM 9085, a high-strength FDM thermoplastic that was tested and met NASA class B/B1 flight hardware requirements (image credit: Stratasys/RedEye)

From March 2012 – April 2013, RedEye produced 30 antenna array structures for form, fit and function testing. As of 2014, RedEye was able to successfully enter the JPL Approved Supplier List and delivered 30 complete antennas for final testing and integration.


IVM (Ion Velocity Meter)

The USAF (U.S. Air Force) is partnering in FormoSat-7/COSMIC-2 and will provide two space weather payloads that will fly on the first six satellites: RF Beacon transmitters and IVM instruments.

IVM is a space weather instrument of AFRL (Air Force Research Laboratory), Kirtland AFB, Albuquerque, NM consisting of three packages: 50)

• IVM (Ion Velocity Meter) sensors, aperture plane and associated electronics

• SPLP (SSAEM Planar Langmuir Probe), sensors, aperture plane and associated electronics

• DCPU (Data Combiner/Power Unit) interface box.

In Feb. 2014, BATC (Ball Aerospace & Technologies Corp.) was awarded a contract from the Defense Weather System Directorate at the Space and Missile Systems Center in Los Angeles, Calif., for the production of the Ion Velocity Meter (IVM) under the U.S. Air Force Space Situational Awareness Environmental Monitoring program to fly aboard COSMIC-2.

The IVM instrument was originally designed by the University of Texas at Dallas (UTD). Ball Aerospace is under contract to build five replicas of the instrument under a firm fixed-priced contract. In addition to other operational space sensor programs, Ball Aerospace employs a disciplined technology transfer process to IVM based on prior collaboration with UTD on the National Polar-orbiting Operational Environmental Satellite System. 51)

The IVM instrument employs gridded electrostatic analyzers to observe and characterize the in-situ plasma. Key observables: in-situ ion density, temperature, & 3D drifts (E-fields).

All sensors are ram-facing. The IVM can measure the electric field perpendicular to the magnetic field and the ion motions parallel to the magnetic field through measurement of the ion drift velocity vector. Two sensors are part of the IVM package, the RPA (Retarding Potential Analyzer) and a DM (Drift Meter), which together provide data to determine the total ion concentration, the major ion composition, the ion temperature and the ion velocity in the spacecraft reference frame.

The SPLP is designed to measure absolute ion density, ion density fluctuations, and electron temperature. The SPLP has two independent sensor heads: an IT (Ion Trap) and a SP (Surface Probe). The Ion Trap is responsible for absolute ion density and density fluctuation measurements at sample rates up to 1 kHz for the identification of scintillating regions. The Surface Probe primarily measures electron temperature but also provides electron density, spacecraft potential and if necessary can perform the ion density fluctuation measurement. The power and data interface for IVM and SPLP is provided by the DCPU. It provides a single electronic interface between the spacecraft bus and the IVM sensors.


Figure 20: Illustration of the IVM/VIDI instrumentation (image credit: USAF AFSPC SMC/WMA, Ref. 24)


RF Beacon instrument:

The RF Beacon includes the sensor electronics and antenna. The RF Beacon will transmit a coherent signal at frequencies in the UHF, L-band and S-bands. Ground receivers will intercept the signals and derive information on ionospheric scintillation.

• The ITT antenna design is a cylinder of 25 cm in diameter and 29.1 cm tall.

• The SRI RF beacon antenna unit will be set of 3 nested quadrafilar helix antennae, with outermost and largest element (UHF) to be ~ 14 cm in diameter and 23 cm high, and mounted on a circular base plate/ground plane approximately 25 cm in diameter. The complete antenna unit has a volume of 25 cm x 25 cm x 35 cm.


Figure 21: Photo of the RF Beacon Electronics Unit (left) and the Antenna Unit (image credit: NOAA, AFRL)



Ground segment:

NSPO will fully utilize the current ground facility to accommodate the mission needs of FormoSat-7 including: 52)

• SOCC (Satellite Operations Control Center) to manage and conduct the FormoSat-7 mission operations

• Three existing S/S-band TT&C stations located in Chung-Li and Tainan to track and establish links with the spacecraft

• SOCC GCN (Ground Communications Network) to provide data transmission between SOCC and the external segments of RTS, Payload DPC, and Launch segment.


Figure 22: Overview of COSMIC-2 operational processing (image credit: UCAR, NSPO)

• With FY14 funding, NOAA is creating an initial ground architecture leveraging domestic and international partnerships (Ref. 18).

- Working with USAF to determine if existing Mark IVB sites can be utilized to support the COSMIC-2 mission

- USAF and NOAA working together to determine technical implementation and costs associated with implementation.

• International ground site collaboration:

- Taiwan ground site will be primary commanding

- Options for use of Australia's (BOM) site infrastructure at Darwin still in discussion

- In cooperation with Brazil, their space agency (INPE) has procured a COSMIC-2 compatible antenna that will become part of the COSMIC-2 ground architecture.

Ground station location


Level of Commitment





Uses existing capability

Cuiaba, Brazil



INPE awarded contract for GS in Jan 2014, MOU with NOAA in final coordination

Darwin, Australia



BOM and GeoScience Australia discussing path forward to provide dedicated support

Mark IV-B – Hawaii



Working with USAF to establish compatibility with COSMIC-2 downlink

Mark IV-B – Guam



Working with USAF to establish compatibility with COSMIC-2 downlink

Mark IV-B – Honduras



Working with USAF to establish compatibility with COSMIC-2 downlink

North Africa

Commercial Service


Subject of a FY15 solicitation for Data Services from commercial providers

Mauritius* (TBD)

Commercial Service


Subject of a FY15 solicitation for Data Services from commercial providers

Table 8: COSMIC-2 Equatorial Ground Stations (planned)


Figure 23: FormoSat-7/ COSMIC-2 candidate sites for 24º orbit data recovery (image credit: NOAA, NARLabs, Ref. 28)


Figure 24: Radio occultation constellation passes from FormoSat-3/COSMIC to FormoSat-7/COSMIC-2 in the next few years (image credit: NARLabs, Ref. 27)


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The information compiled and edited in this article was provided by Herbert J. Kramer from his documentation of: "Observation of the Earth and Its Environment: Survey of Missions and Sensors" (Springer Verlag) as well as many other sources after the publication of the 4th edition in 2002. - Comments and corrections to this article are always welcome for further updates (

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