Elliot Buller Luke Ciavonne Mehdi Mehrpartou Advisor: Dr. Steven Reising

Passive microwave measurement device Measures black body radiation Tuned to resonant frequency of water vapor ( 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

DevicePower (prev)‏Power (new)‏ Computing System6.9 W1.8 W Analog Board5.6 W0.5 W RF2.5 W Total15 W4.5 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

Flavio Iturbide-Sanchez Olivera Notaros Dr. Steven Reising Pat Kusbel Sharmila Padmanabhan