2017-11-08 Meeting notes

Date

08 Nov 2017

Time	Item	Who	Notes
5 min	Software	Milica	Status Challenges
5 min	HSI data + software	Jan Otto	Status Challenges
5 min	Mission design and requirements for data	Mariusz	Requirements for data processing and comms.

Not complete (week 44) Unknown User (orlandic) and Unknown User (joaoff) Determine the precision on numbers for implementation in FPGA; custom-made precision (24/32 bit); Match the Matlab precision (64 bit) with the image (16 bit). Floating point vs. fixed point. Computational speed.
Not complete (week 44) Unknown User (joaoff) Actual performance of real HSI camera (take raw images); subtract black frame; test different viewing angles to reference target and exposure times - how it affects SNR; model variance of signal-dependent noise.
Not complete (week 44) Mariusz Eivind Grøtte Look into how GSD<100 m should be achieved, currently it is at 248 m with current slew rate required and optical characteristics
Not complete (week 44) Mariusz Eivind Grøtte Make an energy budget and duty cycle for observations/comms.
Not complete (week 44) Mariusz Eivind Grøtte and Unknown User (joaoff) Iterate on HSI memo to Steve
Not complete (week 40) Mariusz Eivind Grøtte Get preliminary results from EOIR tool in STK (or MODTRAN) on "what can we see from space"
Not complete (week 40) Unknown User (rogerbi) A cost benefit analysis of power usage vs compression for comms.
Not complete (week 40) Unknown User (sivertba) Find a student to do thermal analysis and coordinate with Mariusz
Not complete (week 40) Give feedback on Gantt chart (ALL) - Still want a list of activities from each - respond to emails

Introductions to Gara Quintana (new PhD student on SDR for SmallSats, Torbjørn Ekman)

Joao works on HSI report (UAV test flights) for the RCN application (see Project Documentation Folder in GDrive)
Currently doing SNR calculations (raw images)
- Trade-off between SNR and resolution in binning
- SNR doesn't tell the story (just a small part of it - but it is a measure of performance)
Need to understand how binning affects SNR, resolution and data end-product
Fred is writing a white paper on the HSI (version 4) - sent out to Tor Arne and Mariusz
- Second order effects (800 nm and up)
- Jan Otto knows of a couple of methods to mitigate these effects
- Well understood now that 800 nm and above is good
Sivert is looking into invariant areas/objects in the EM spectrum,
- How to utilize that for calibration
- Egil explains Rayleigh scattering (scattering of longer wavelengths on larger particles - e.g. aerosols, water vapor)

SD-card + 1 GB storage, enough memory for experimental raw data
HSI data will be transmitted thru serial/CAN directly to Radio (providers will fix the interface)
Just need to understand the format to be sent on from PCB
CAD prototypes will be 3D-printed (encasing and lenses), 5 in total. 3 for HSI ver.4, and 2 for HSI ver. 5. Julian has found a person to do it.

Testing the projection core
Comms. for memory
- Will test this on the test development board soon
Harald sent email on modifications to EMSC - should be looked at
What are the consequences on implementation (Milica & IdleTechs coordinate)
Bitwidth for loadings and data need to be established
Master students have written status reports + Milica's updated tech report (may be found on Project Documentation folder in GDrive)

Mission Design

Determining constraints for data processing for a target of 50x30 km (provides requirements for Idletechs processing)
- Optical resolution: 250-266 m
- Swath width: 30-32 km
- GSD = 39 m
- Spatial resolution ~ 306 m
- Angle from Nadir: 20 deg
- Observation duty cycle: 54 s
- Comms duty cycle: 1 min
- Image resolution: 500 x 580 pixels
- Exposure time matters a lot: i.e. need to establish what is a good shutter speed for the camera ('good' SNR vs. spatial resolution)
- Possible to do the OTFP during the exposure times? Likely better to collect all data then do the processing (another limit on time schedule) - need to see if it can be done less than a minute.
Data budget well within reach (also uncompressed) but it is clear that S-band is needed, UHF/VHF used for uplink or experimental downlink.
Need to understand how the actual HSI signal responds to viewing angles (currently set at 20 deg, may we push this to 30 deg?). Need to see some analysis on this.

(All) read Fred's white paper, will be sent out
End of this year we need specs on satellite on-board processing + mission reqs for the public tender to select UTIAS/Tyvak/Gomspace/others
Mariusz: work on the concept document and send it out to everyone on Friday. Plus catch up on the previous action items. This doc will include firm requirements in the mission design and data processing.
Milica and Jan Otto need to coordinate on the bitwidth (action item as before)
SNR on raw data (action item as before)
Mariusz: give access to Gara and Egil for GDrive; give Gara recommendations on what to read