GSSI SIR 30, Руководство пользователя

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Geophysical Survey Systems, Inc. SIR® 30
Manual
MN 93-101 Rev E 36
extraneous data are collected. The horizontal scan density or lateral resolution required for a specific
application is dependent on many factors including the electrical properties of the media and the target or
structure of interest, the wavelength of the central frequency of the antenna and the depth to the target.*
UNIT/MARK:
This setting controls how often the SIR 30 will write a distance mark in the data file and on
the data acquisition display. Distance marks provide the User a quick visual indicator of distance travelled
The Unit/Mark setting is stored in the radar file header.
MAX UNITS/FILE:
This setting controls the total expected size of an individual data file distance units.
When the User starts data collection, the SIR 30 will reserve a block of the specified amount of memory
sufficient to store the file. This number does not need to be exact. If you leave this setting at the default
value of 0 the SIR 30 will reserve a memory block size equivalent to 5 GB per channel.
The horizontal resolution is defined as:
*
∆𝑙𝑙 =
�
𝑑𝑑𝜆𝜆
𝑐𝑐
2
Where:
d = Depth
𝜆𝜆
𝑐𝑐
=
Wavelength of the central frequency of the antenna
c = lightspeed
(Annan, 2001)
GPS:
If you are using a GPS with the SIR 30, select CUSTOM from the GPS Type and enter the location
of the GPS receiver antenna with respect to the Channel 1 GPR antenna. If the GPS antenna is mounted to
the Channel 1 GPR antenna, both the X and Y values will be zero (0). If the GPS antenna location is
behind the Channel 1 antenna location, the X value will be the distance of the GPS behind the GPR
antenna, and the number will be negative. The Y value determines how far to the right or left the GPS is
relative to the GPR antenna connected to Channel 1. If you are standing behind the antenna, facing in the
direction of your survey profile, this number will be positive if the GPS antenna location is to the left of
the GPR antenna and negative if the GPS antenna location is to the right of the GPR antenna.
Figure 54: GPS set to CUSTOM, GPS is enabled.