User's Manual

Geophysical Survey Systems, Inc. 2.0 GHz Antenna
Model 42600
2.0 GHz, Model 42600Antenna
The Model 42600 antenna represents the state of the art in high-frequency, air-launched GPR antennas for
near surface infrastructure assessment. It has excellent near surface resolution in a revolutionary small
form factor. The Model 42600 is an air-launched antenna and is designed to be used suspended over the
survey surface and not in contact with it. The Model 42600 can be used in distance (survey wheel) or time
(continuous) modes.
Smart Antenna
The Model 42600 is a 2.0 GHz “smart” antenna. This antenna has a special chip in it that will work with
the SIR-4000, SIR-30, and future control units (not the SIR-3000 or SIR-20). This chip will identify the
antenna to the SIR-system control unit so that the controller will be able to automatically load up the
correct default settings. The 42600 will not function with a SIR-3000, SIR-20 or any of GSSI’s previous
controllers, as these previous controllers are not compatible with digital antennas. By digital antenna, we
mean an antenna that digitizes the analog signal received before sending it to the controller. An analog
antenna will send the signal to be digitized on a controller.
System Setup - Standard Settings
Preset Settings:
Range/Depth is approximately 20 cm (8 inches) assuming a dielectric constant of 5.
Collect Mode: Distance (recommended) or Time
Scans per Second: 150 (recommended)
Samples per Scan: 512
Depth Range: 20 cm (8 inches)
Bits per Sample: 32
Specifications
Center frequency: 2.0 GHz
Pulse duration: 0.5 ns
Depth of penetration: 0-0.75 ft depending on dielectric permittivity