Features:

• Maps internal layers to a depth of 200 m with 10 cm resolution
• Generates an extremely linear chirp signal with minimum variation in transmit power for improved sidelobe performance
• Fast sweep rate.
• Compact PCI form factor

System Specifications:

System Overview

The system has 5 modules, as follows:

• A Phase-Locked Loop system to generate the transmit signal.
• An Automatic Gain Control system to level the transmit power.
• A Phase-Locked Oscillator system to down convert the transmit signal.
• An RF receiver board.
• An IF receiver board (to match the received signal to the dynamic range of the A/D converter)

FM-CW Radar Principles

In FM-Cw radar, a chirp signal is transmitted, hits a target and is mixed with the transmit signal. If many targets are present, the IF signal will be a superposition of many signals at different beat frequencies. The beat frequency is B_/T and the resolution is c/2B.

The entire operational radar fits on one aluminum compact PCI card and is placed in a compact PCI case along with the data acquisition systems and the WCORDS system.

Delay Line Test

Corrected Spectrum (Blue) vs. Ideal Spectrum (Red) after removing the delay line effects and the system effects.

Radar In Action - 2004 Field Experiment

Results:

Internal layers were successfully mapped at both NGRIP (2003) and Summit (2004), Greenland with high resolution to a depth of 200 m.

The water-equivalent accumulation rate at Summit was determined to be 36 cm/yr.