System Calibration

Fernando Rodriguez-Morales

August 7th, 2007

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Outline• Overview• Network analyzer measurements

– Calibrated delay– Antennas

• Delay-line response• Other measurements

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Calibration overview– Transmitter/receiver

transfer function is determined

– Antenna response is determined.

Calibration is used to remove systematic errors from the measured data.

Calibrated delay

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Network Analyzer Measurements

• Used to determine the transfer function of a calibrated delay.

• S-parameter files are downloaded and stored in a computer.

• Phase and amplitude information available.

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Left Antenna

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Right Antenna

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Computer

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VNA

Network Analyzer Measurements

The VNA is also used to determine the transmission coefficient of the antennas (from the reflection coefficient).

Computer

Left antennas Right antennas

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Delay line measurements

• Performed to compensate for amplitude and phase differences in the system.

• Transmit/record waveforms for different bandwidths and pulse durations.

• System response (including power amplifiers) can be determined.

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Delay line measurements

Delay line setup Sample waveforms

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Other Measurements

Fly over the ocean (or smooth surface) to collect data over a distance of 10-20 km.

Roll measurements to determine antenna patterns.

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