1. ISUAL System Design Summary H. Heetderks / S. Harris

2. NCKU UCB Tohoku ISUAL System Design Heetderks / Harris TRR December, 20012 ISUAL Science objectives Major Science objectives: 1. Determine the location and timing of luminous phenomena above thunderclouds to investigate their spatial, temporal and spectral properties. 2. Obtain a global survey of upper atmospheric optical flash transients (sprites, elves, blue jets etc.) 3. Global observations of aurora and airglow

3. NCKU UCB Tohoku ISUAL System Design Heetderks / Harris TRR December, 20013 ISUAL Science Operations Strategy Instrument Mounted on ROCSAT2 S/C in 891 Km Polar Orbit Science Data Collected on Night Side of Orbit ROCSAT2 S/C reoriented to Point ISUAL at Limb or Somewhat Below at Beginning of Pass Pointing may be Either Along the Track or Cross Track Data are Stored and Compressed in on Board Memory and Transferred to the S/C Memory at the end of each Orbit After 14 Orbits, the Data are Telemetered from the S/C Memory to the Ground

4. NCKU UCB Tohoku ISUAL System Design Heetderks / Harris TRR December, 20014 ISUAL System Electrical Block Diagram

5. NCKU UCB Tohoku ISUAL System Design Heetderks / Harris TRR December, 20015 ISUAL Instrument Complement Sprite Imager –Gated Intensified CCD camera –512 X 128 pixel resolution –20 deg. X 5.0 deg. Field of View –Filter wheel has six selectable filters Spectrophotometer –Six photometer modules are identical except for spectral characteristics –20 deg. X 5.0 deg. Field of View –All photometers are boresighted in the same direction as the imager –All six channels are sampled at a 10 kHz rate

6. NCKU UCB Tohoku ISUAL System Design Heetderks / Harris TRR December, 20016 ISUAL Instrument Complement (con’t) Array Photometer –Two photometer units, identical except for optical filter bandpass –20 deg. X 3.15 deg. FOV divided into 16 channels –Selectable sample rate –Boresight same as other instruments Associated Electronics Package –Performs power distribution and control –Performs command decoding –Controls instrument and sensors –Performs compression of images –Stores 128 Mbytes in Mass Memory –Generates CCSDS telemetry packets

7. NCKU UCB Tohoku ISUAL System Design Heetderks / Harris TRR December, 20017 Resource Requirements Summary -- Mass

8. NCKU UCB Tohoku ISUAL System Design Heetderks / Harris TRR December, 20018 Resource Requirements Summary -- Power Typical Orbit: Mode 6 -- 40% Mode 5 -- 30% Mode 4 -- 30% * Gives 34.0 Watts Orbit Average (40.0 W Allocated) * Gives 44.1.0 Watts Peak (100.0 W Allocated) Note that the above assumes no heater power needed during science operations This is subject to change as a result of ongoing thermal analysis.

9. NCKU UCB Tohoku ISUAL System Design Heetderks / Harris TRR December, 20019 ISUAL Sprite Imager Filter Wheel Enclosure Input Collimator Daylight Sensor Filter Wheel Motor MCP HV Supply Phosphor HV Supply Front End Electronics (FEC) Lens Enclosure Volume: ~250 H x 240 W x 362 L (mm) Max Power: 14.0 W Mass: 7.45 kg

10. ISUAL Sprite Imager

11. NCKU UCB Tohoku ISUAL System Design Heetderks / Harris TRR December, 200111 Imager Optical Path

12. NCKU UCB Tohoku ISUAL System Design Heetderks / Harris TRR December, 200112 Optical Specifications Filters –1:623 - 750 nm –2:762 nm –3:427.8 nm –4:630 nm –5:557.7 nm –6:Open - Wideband

13. NCKU UCB Tohoku ISUAL System Design Heetderks / Harris TRR December, 200113 CCD Active Area Masking Imaging Earth Limb –Narrow, 4:1 Aspect Ratio –CCD Active Area –Mask applied to f/o taper –Size: 1024 x 256 (unbinned) –Size: 512 x 128 (binned) –FOV: 20° x 5º Top view of Dalsa CCD with f/o assembly Fiber Optic Taper Fiber Optic Window

14. NCKU UCB Tohoku ISUAL System Design Heetderks / Harris TRR December, 200114 Imaging Modes Aurora –Exposures taken continuously –Programmable exposure duration, relatively long (~1 sec) Sprite Continuous –Exposures taken continuously –Programmable exposure duration, relatively short (~1 - 10 ms) –Programmable repetition period (~1 - 10 ms) –Images saved in Mass Memory, as Triggered by Event Sprite Burst –Exposures taken in bursts of 8 images, Triggered by Event –Programmable exposure duration, very quick (~1 - 10 ms) See Document 8765-W7C for detailed information

15. NCKU UCB Tohoku ISUAL System Design Heetderks / Harris TRR December, 200115 Frame Timing Example - Sprite Continuous Notes: 1.ETRIG signals the Sprite Event occurrence 2.Exposure duration (signal EXP) programmed by parameter ExpDuration 3.Frame repetition period programmed by parameter RepPeriod 4.Frame readout period (signal FRMV) is fixed, ~10 ms 5.Number of Pre- and Post-Event images programmed by NumPreTrig and NumPostTrig. Example Parameters: RepPeriod = 5 ms ExpDuration = 4.2 ms NumPreTrig = 1 NumPostTrig = 6 ETRIG EXP FRMV

16. NCKU UCB Tohoku ISUAL System Design Heetderks / Harris TRR December, 200116 Imager Lens-CCD Assembly

17. NCKU UCB Tohoku ISUAL System Design Heetderks / Harris TRR December, 200117 Imager Box/FEC Assembly

18. NCKU UCB Tohoku ISUAL System Design Heetderks / Harris TRR December, 200118 Imager Filter Wheel/Housing Assembly

19. NCKU UCB Tohoku ISUAL System Design Heetderks / Harris TRR December, 200119 Imager Assembly

20. NCKU UCB Tohoku ISUAL System Design Heetderks / Harris TRR December, 200120 Spectrophotometer Description Six Channels Identical except for Spectral Bandpass 50 mm f/2 Lens Aperture limits FOV to 20 deg X 5 deg Uses Ruggedized EMR Photomultiplier Tubes Individually Adjustable HV for each Unit Six Co-aligned Modules Packaged with HV and Pre- Amps as one Unit Remainder of Electronics contained in AEP

21. NCKU UCB Tohoku ISUAL System Design Heetderks / Harris TRR December, 200121 Spectrophotometer - One Channel Input CollimatorStim LEDPMT Insulating Sleeve Housing Filter / Heater Ass’y LensAperturePhotomultiplier Tube

22. NCKU UCB Tohoku ISUAL System Design Heetderks / Harris TRR December, 200122 Mechanical Layout of Complete Unit Optical Alignment Cube High Voltage Power Supply, Three per Side Single PMT Channel J5 - Spectrophotometer Power and Data Volume: ~187H x 156 W x 244 L (mm) Mass: 5.08 Kg Max Power: 6.8 W

23. NCKU UCB Tohoku ISUAL System Design Heetderks / Harris TRR December, 200123 Photometer Module Assembly

24. NCKU UCB Tohoku ISUAL System Design Heetderks / Harris TRR December, 200124 Spectrophotometer Assembly

25. NCKU UCB Tohoku ISUAL System Design Heetderks / Harris TRR December, 200125 Mechanical Envelope of the Array Photometer Viewing Direction 236 mm 359 mm 238 mm Mass: 11.0 kg Max Power: 16.4 W

26. NCKU UCB Tohoku ISUAL System Design Heetderks / Harris TRR December, 200126 Top View of the Array Photometer

27. NCKU UCB Tohoku ISUAL System Design Heetderks / Harris TRR December, 200127 Side View of the Array Photometer

28. NCKU UCB Tohoku ISUAL System Design Heetderks / Harris TRR December, 200128 Array Photometer Data Modes a. Sprite 1 Mode : S_MODE_SPRITE2 sampling rate=20KHz, fc(LPF)=10 KHz b. Sprite 2 Mode : S_MODE_SPRITE20 sampling rate=2KHz, fc(LPF)=10KHz c. Auroral Mode : S_MODE_AURORA sampling rate=200Hz, fc(LPF)=100Hz Science data format is 12 bits serial. Nominal DATA_CLK frequency is 5MHz.

29. NCKU UCB Tohoku ISUAL System Design Heetderks / Harris TRR December, 200129 Functional Diagram for Array Photometer 8 ch

30. NCKU UCB Tohoku ISUAL System Design Heetderks / Harris TRR December, 200130 2 KHz20KHz 18ms 82 ms S_MODE_SPRITE2S_MODE_SPRITE20 18 ms 10 ms AP Trigger Sequence Triggered by Cloud Flash Triggered by Sprites

31. NCKU UCB Tohoku ISUAL System Design Heetderks / Harris TRR December, 200131 AEP Mechanical Design System Consists of Six Circuit Boards, each Surrounded by an Aluminum Frame –Low Voltage Power Converter is on top to conduct heat to thermal radiator –Power Controller, Data Processing Unit, Instrument Data Controller, Mass Memory, and Data Compression Module follow in order –Base Plate mounts unit to spacecraft deck Electrical Connections made with Stacking Connector on each Board –Avoids need for Mother Board Thermal Radiator attaches to feet on top of assembly Walls of Frames are.200 inches thick to provide radiation shielding and a heat path to the thermal radiator The Stack is held together with 10 Skewer Rods

32. NCKU UCB Tohoku ISUAL System Design Heetderks / Harris TRR December, 200132 AEP Mechanical Assembly Max Power: 19.4 W Mass: 5.2 kg

33. NCKU UCB Tohoku ISUAL System Design Heetderks / Harris TRR December, 200133 Exploded View of AEP Assembly Bottom Plate DCM Mass Memory Instr Data Controller DPU Power Controller LVPS

34. NCKU UCB Tohoku ISUAL System Design Heetderks / Harris TRR December, 200134 Power System Block Diagram

35. NCKU UCB Tohoku ISUAL System Design Heetderks / Harris TRR December, 200135 DPU Functions Receives Commands Sends Status Manages Mass Memory Manages Power System Controls Telemetry from Mass Memory Controls Imager Controls Spectrophotometer Commands Array Photometer Manages Instrument Heaters

36. NCKU UCB Tohoku ISUAL System Design Heetderks / Harris TRR December, 200136 DPU Block Diagram HV Control (FPGA) Diag. Port (EGSE) CDI Sender STIM DCM Handshake Mass Memory I/F 8085 CPU Science Telemetry SOH Telemetry Command Rx Time Rx 32 KB PROM 128 KB RAM 128 KB EEPROM Sci Telem Command Sts. Commands PPS 4 PR 1 PR Spacecraft Interface (RS-422) DPU Board To Imager MCP, Imager Phosphor, SP1-6 HVPS Daylight Sensor To Imager To AP, SP To DCM, PC To Imager To SP To DCM To Mass Memory

37. NCKU UCB Tohoku ISUAL System Design Heetderks / Harris TRR December, 200137 Mass Memory Description 2.6 GBits organized as 64 M x 40 bits 32 bit data word after EDAC 7 bit Error Correction Code per word corrects all single bit errors and detects all double bit and some multiple bit errors. Base device is Samsung K4S560832A-TL1H 256 Mbit chip organized as 32M x 8bits.

38. NCKU UCB Tohoku ISUAL System Design Heetderks / Harris TRR December, 200138 Mass Memory Interfaces Imager IDC/ Mass Memory DPU 12 DATA SP AP CLK STB DATA-1 CLK STB DATA-2 DATA CMD0 CMD1 CLK DCM 32 2 DATA 26ADDR MBUSY 2 2 Telemetry CLK DATA RTS CTS R/W ACQUIRE 2

39. NCKU UCB Tohoku ISUAL System Design Heetderks / Harris TRR December, 200139 Mass Memory Block Diagram 32MB SDRAM Level Shift Level Shift Data Interface Address Interface Imager AP SP DPU DCM TLM

40. NCKU UCB Tohoku ISUAL System Design Heetderks / Harris TRR December, 200140 Usage Scheme Circular buffers Fill on trigger –M Pretrigger –N Posttrigger Buffer switch Buffer Allocation Trigger M N AA Buffer Allocation B

41. NCKU UCB Tohoku ISUAL System Design Heetderks / Harris TRR December, 200141 Data Compression Module Interface - Between DPU and DCM 1.DCM_BSY 2.DCM_ATN 3.CDI-CCLK 4.CDI-DAT 5.CDI-STB - Between MM and DCM 1. Address Bus (26bits) 2. Data Bus (32bits) 3. Read/Write enable 4. DMACK Image

42. NCKU UCB Tohoku ISUAL System Design Heetderks / Harris TRR December, 200142 DCM Description Loads program from Mass Memory (MM) Receives commands from DPU via Mass Memory using MM Control Blocks (MMCB) Reads Image data and Photometer data from MM and compresses both Compressed data is stored in PVCF form in MM Compression schemes: –Windowing region-of-interest in Images –Range coding using Predictor codes (similar to JPEG)

43. NCKU UCB Tohoku ISUAL System Design Heetderks / Harris TRR December, 200143 Coding work flow IMAGE DATA Store Image Sprite image Windowing image yes No Store 2 images Coding Image Packet IMAGE DATA (range code) (windowing code)