Noggin 1000 Smart Cart, Руководство пользователя

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Smart Systems User’s Manual Version 1.1
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Noggin System
The Noggin System should be set to the type of Noggin currently in use on the Smart
System. The Noggins available are:
1. Noggin 250
2. Noggin 500
3. Noggin 1000
Stacks
Some materials tend to absorb radar signals and limit penetration. These materials are
said to be lossy. When collecting data in lossy areas or areas with a lot of radio
frequency noise, one way of increasing data quality is to collect more than one trace at
each survey position, average them and save the averaged trace. This is known as
“stacking”. Data quality improves because the noise, which is usually random (like white
noise on a TV screen with no station in the area), tends to zero when averaged.
Consequently, the usable signal is easier to see. This is known as increasing the “signal-
to-noise ratio”.
The amount of Stacking can vary from 1 to 2048 by factors of 2.
While stacking improves data quality, it also forces the user to slow down survey
production. The more stacks the longer it takes to collect data at each survey position.
Therefore, it is important to find the lowest number of stacks that still reveal the target
adequately. For most surveys, stacking 4 times is suitable.
See the warning in Section 6.2.7 about losing data if the Smart System is moving too
quickly for the Noggin system to keep up.
Linear Time Gain
As described in Section 6.2.6, the weak signals must be amplified or “gained” to see
them on the display. The Gain button described in Section 6.2.6 can be set to a value
from 1 to 9 depending on the amount of gain required (1 is lowest gain, 9 is highest
gain).
There is also a second level of gain available to the user and that is the Linear Gain
setting. The default Linear Gain setting of 2.0 is usually adequate for most ground
conditions, however, if advanced users find that they are surveying in areas where high
Gain button settings are always required to see data, it may be advantageous to
increase the Linear Gain setting. Conversely, if the user finds that low Gain button
values work to see the data, it may be useful to decrease the Linear Gain setting.
For the experienced user, the setting indicates the gain increases per nanosecond.
The Linear Gain setting can vary from 0.0 to 5.0 in steps of 0.5.