Sensors & Software Inc. NG250 ユーザーズマニュアル
Noggin
G-2
receiver (Rx)
General term for electronics devices used to detect fields and translate signals into
records or displays
records or displays
resolution
The minimum separation of two objects before their individual responses merge into a
single response
single response
signal amplitude
A measure of the strength of the radio wave signal
station interval
Spatial distance between observation points along a survey traverse line or mesh
points on a grid
points on a grid
step size
See station interval
transmitter (Tx)
General term used for electronics devices used to create propagating electromagnetic
fields
fields
transducer
Name used where GPR antenna, electronics, and shield are combined into one physi-
cal unit
cal unit
sample point
Signal amplitude measured at specific point in time
trace
Sequence of sample points from a single GPR channel that indicate time variation of
signal amplitude
signal amplitude
cross section
Image that results from side-by-side display of a number of traces which are from adja-
cent spatial measurement position
cent spatial measurement position
gain
Process of amplifying signals to match recording device or display dynamic range
G-2 Common GPR Terms
zone of influence
The size of an area on a reflecting feature that can be uniquely resolved. (See lat-
eral resolution length).
eral resolution length).
fresnel zone
See zone of influence.
range resolution length The radial distance separation between two objects that is needed so that a GPR
clearly detects two responses.
lateral resolution length The lateral separation between two objects that is needed so that a GPR clearly
detects two responses.
ringing
Impulsive GPR signals can give rise to reverberating responses that oscillate for a
much longer time than the GPR pulse or wavelet. Such a response is referred to
as a "ringing" response or "ringing" for short.
much longer time than the GPR pulse or wavelet. Such a response is referred to
as a "ringing" response or "ringing" for short.
hyperbola
Characteristic inverted "U" GPR response from a point target. (Mathematical form
of the position-travel time response from a point target)
of the position-travel time response from a point target)
signal to noise ratio
The ratio of GPR signal amplitude to the average noise amplitude. A large ratio
results in a larger penetration depth or detection of weaker signals.
results in a larger penetration depth or detection of weaker signals.
system performance
Measure of system exploration depth indicated by the ratio of transmitter output
power or voltage to receiver noise power or voltage.
power or voltage to receiver noise power or voltage.