PHEOS PSRR

Concept of Operations

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Scope

The purpose of the PCW-UVI Concept of Operations (ConOps) is to communicate how mission systems will operate, with special consideration given to end user functionality.

Our end users are described in CDRL EN3 – Mission Requirements Document.• Scientific Community (National and International)• Space Weather Applications Community

• GNSS User Community• Space Weather Prediction/Alerts (NRCan, NOAA, etc.)

• Education and Public Outreach Communities

Drivers of the ConOpsData Product Content (coverage)Data Product Availability (Data Product Latency

The PhaseA ConOps describes mission systems level operations and some payload subsystem operations.

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Payload Operations – Operational Modes

• During the initial on-orbit operations, special steps are followed

• During normal orbits, the instrument is transitioned to a lower state while not imaging

Survival Mode

Safe Mode

Science Mode

Off Mode

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Payload Operations – Operational Modes

During initial on-orbit operations:• Transition into survival mode ASAP after launch

(unless spacecraft is launched with survival heaters already active)

• Wait for spacecraft outgassing (several weeks)• Open the doors• Waiting a bit longer to be HV safe (several days)• Initial slow power up of HV rails to nominal level,

stopping at intermediate levels and monitoring current draw, voltage levels and temperatures

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Payload Operations – Operational ModesDuring nominal on-orbit operations• When 28 v are applied to the main power interface, the instrument goes through a power up sequence• The instrument is now in SAFE MODE• The instrument can now receive commands and send telemetry however the HVPS is disabled and the

science data interface is inactive• The HVPS is enabled and powered up • The high voltages are ramped up in a controlled manner to the nominal value and the science data

interface becomes active (SCIENCE MODE)• Images are acquired on a continual basis • Commands can be sent with various parameters such as integration time, bin size, sub-frames per image• The internal clock will be used to time stamp each image• The internal clock is synched to the GPS interface periodically• The image data is transferred to the spacecraft while the next image is being acquired• After the image acquisition part of the orbit is complete, the HV is commanded to zero and the doors

are commanded closed (SAFE MODE)• Before the image acquisition phase of the next orbit starts, the door is commanded open, and HV is

commanded back on, the unit stabilizes thermally and is ready to repeat the process (SCIENCE MODE)

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Payload Operations – Imaging Duration

TAP66Molniya

The PCW-UVI Area of Interest (Aoi) is nearly identical to the Meteorological (MET) Payload (a primary driver of the PCW Concept of Operation).

PCW-UVI should acquire images of the AoI sufficient to maintain 24/7 coverage.

Tundra

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Payload Operations – Data Handling

Our nominal data rate is not expected to exceed 0.25Mbps, and will likely be below 0.025Mbps.

A typical instrument cycle will produce two image frames (one per camera + header) every 20 seconds. The packet will then be presented to the s/c bus for packaging and relay to the ground station.

Depending on the transmission cycle of the bus, we expect data to be received on the ground with a latency of no more than 5 minutes.

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• Our primary philosophy for data production is automation. – We will automate as many key aspects of data

product generation and distribution.

Ground Operations