High speed DSP for infrared space camera

1. High speed DSP for infrared space camera Martin Grim

2. Contents • SRON and the Space Kids Consortium • Context • Kinetic Inductance Detector • Read-out principle • System architecture • Software www.spacekids.eu www.sron.nl www.facebook.com/sron.nl

3. SRON and Space Kids consortium • SRON • One of 8 Scientific Institutes of NWO • Scientific research in and from outer space • Astrophysics, exo planets, earth and climate • Instrument realization from start to finish • Space Kids consortium

4. Context • Why infrared? • Research into star, galaxy and planet formation • Star formation only visible as glowing dust • Research into the young universe (approx 600·106 years old) • Expanding universe leads to red shift (towards infrared) • Big questions What is the universe made of and how does it evolve? How do galaxies, starts and planets form and evolve? Are we alone?

5. Orion

6. Future (IR) space instruments • Extremely cold primary mirror (4 K) • Extremely sensitive detector • Dedicated detector read-out • Low noise • High speed • High multiplex factor SPICA (launch 2025?)

7. Kinetic Inductance Detector

8. Current pixel design Si lenses @ chip back Feedline Connects all KIDs to readout 1 mm Al central line Radiation absorbed Resonator Length sets F0 5mm = 6 GHz 0.1 mm Lens Ground plane No radiation absorption Antenna In lens focus

9. 1 2 Si Lens Radiation 1 2 Readout signal ~GHz Kinetic Inductance Detector • Very sensitive super conducting radiation detector • operate at 100-300 mK • resonance changes due to incoming radiation • measure change in amplitude/phase of carrier • all carriers for all KID simultaneously present

10. KID read-out system • KID read-out • integration of signal read from all detectors • FFT on integrated signal • Masking to select the bins which correspond to a KID resonance

11. Readout principle

12. High level requirements • carriers 2000 (pixels) • blind carriers 10% • data points 216 or 219 complex points • analog bandwidth 2.0 GHz • sampling speed 2.0 Gs/s per channel (I, Q) • frame averages 24 or 192 (216vs 219) • system noise to carrier ratio 94 dBc/Hz • DAC, ADC, CLK, PSU, RF • RF, DACs, ADCs synchronized external 2.0 GHz clock • FFT: 160 or 1280 Hz (219vs 216)

13. Chosen system • COTS hardware • FMC and Virtex7 technology • QDR2 memory • Full integration • Focus on firmware/DSP • PC based SW control • Science pipe line

14. Space KIDs prototype system

15. Space KIDsreadouthardware

16. Current implementation • In firmware • Carrier comb processing • WOLA performed • FFT performed • Carrier select • Command and Control • SRON generic instrument control software • Control of hardware • Control of measurement • Displaying (level 0/1) science data • Displaying health

17. Software: today and future • Carrier comb • Python science control software (offline, PC) • Find KIDs in spectrum: 2nd derivative, check against threshold • Calibrate signal: remove modulated carriers, flatten base • Calibrate ADC and DAC frequency dependent gain • Calibrate I-Q phase difference • Deal with strong and weak sources • Space System: • Perform the above in embedded system (semi real-time) • Add • Low power, low memory, low μP performance • Static memory allocation • Lossless data compression • Fault management • Redundancy • (near) 100% code coverage

18. Space KIDs: the future • Finish current research • Investigate migration to space-like system • Investigateembedded processing • Investigate alternatives for WOLA and FFT • Go to TRL 5 or 6 within 2-3 years?

19. Questions