Download Fall 2007 Powerpoint presentation (Office 2007)

Advisor:
Dr. Steven Reising
• Elliot Buller
• Luke Ciavonne
• Mehdi Mehrpartou
• Passive microwave measurement device
• Measures black body radiation
• Tuned to resonant frequency of water vapor
(22.235 GHz)
• Extremely sensitive to changes in water vapor
• Can detect water vapor through cloud cover
• Forecasting weather
•Measuring sea surface temperature
•Cloud cover
•Precipitation rate
• Predicting larger regional and global trends
• Study of atmosphere and surfaces of planets
• Embedded Intel SBC running
Windows 98
• Off the shelf boards for data
acquisition
• Custom power conditioning circuit
• Limitations
• Prone to failure
• Power requirements
• Heat produced
• Low power consumption (<3 Watts)
• Small Size
• Reliable
• Low latency interrupt response
• Sufficient I/O ports (3 Serial ports, 16 A/D channels)
• Two board solution:
• Custom designed 4 layer PC104 daughter card
designed by Pat Kusbel
• ARM9 based commercial single board computer
• Boards communicate over PC104 bus
Device
Power (prev) Power (new)
Computing System
6.9 W
1.8 W
Analog Board
5.6 W
0.5 W
RF
2.5 W
2.5 W
Total
15 W
4.5 W
• 6 Switching Voltage Regulators
• High Efficiency at High Currents ( > 90%)
• 7 Linear Voltage Regulators
• Low Noise (typically 30 μVrms, 10 Hz to 100 kHz)
• Low Quiescent Current (30 μA)
• Low Output to Input Ratio for Higher Efficiency
• DC Voltage Levels
• Output Voltage Ripple
• Noise
• Stability
• Transient Response
• Electromagnetic Interference (EMI)
• Custom board digitizes 4
analog channels from
Radiometer
• ARM9 board initializes and
controls custom board
• Boards communicate with
each other over PC104 bus
• Custom board includes FPGA
running Microblaze processor
• Processor tasks include:
•Periodically polling ADCs
•Buffering samples on-board
•Maintain local time-base
•Control off-board power to
radiometer
• Processor clock is faster than
PC104 clock
• Provide temporary storage of data
• Send periodic interrupt request to
trigger data dump to ARM9 board
• Receive control parameters from
ARM9 board
• Linux kernel module
•Service Interrupts from FPGA
• SD Card storage daemon
•Shuttles data from device driver to
SD cards
• Temperature control software
•Communicates with Peltier unit to
control temp within 0.1˚C
• Time management
•Communicates with GPS to store
and synchronize time on both boards
• Hardware
•Finish testing power supplies
•Run transient analysis on DACs
•Test all power supplies with dummy loads
• Software
•Write time management software to synchronize with GPS
•Write Microblaze mini-kernel to interface to ADCs
•Write software to control positioning apparatus
•Write user interface to configure device and dump data
Dr. Steven Reising
Sharmila Padmanabhan
Pat Kusbel
• Flavio Iturbide-Sanchez
• Olivera Notaros