This page covers:
A 'single target' in Echoview is the representation of an acoustic echo attributed to a single backscattering target detected within the beam of an echosounder. Each single target has a number of properties. Target Strength and range from the transducer are notable, but many other properties are available for analysis.
Single targets are represented on echograms as colored rectangles. See Single target display below.
They can also be:
displayed on 3D Single Targets graphs,
analyzed on screen or in exports,
used to create 3D single targets that can be viewed in scenes,
viewed with the looped replay of associated multibeam data.
Single targets are displayed in Echoview as colored rectangles.
The color of the rectangles reflects the target strength according to the Color Legend dialog box.
The rectangles are displayed with the width of the ping in which the target was detected and a thickness (height) which is defined as a function of the transmitted or received pulse lengths. See Configuring single target display thickness for more information.
The top of the rectangle is displayed at the depth/range of the single target it represents.
Notes:
Echoview determines the display thickness for single targets using the equation below. You can configure display thickness by changing the appropriate settings on the Variable Properties dialog box.
Display_thickness = Pulse_length x Thickness_factor
Where:
Pulse_length is determined by the ST thickness source selected on the Calibration page of the Variable Properties dialog box.
Thickness_factor is the value entered as Thickness factor on the Display page of the Variable Properties dialog box.
If Pulse_length is determined from the transmitted pulse length it is calculated as follows:
Pulse_length (ms) = c t / 2000
Where:
c is the Sound speed (m/s) entered on the Calibration page of the Variable Properties dialog box.
t is the Transmitted pulse length (ms) entered on the Calibration page of the Variable Properties dialog box.
Notes:
Use the Target length conversion operator to create a single target variable (of data type target length) that reports the estimated length of each detected target.
For more information refer to Target length from single beam data .
You can threshold to isolate targets of interest in a single targets variable by using the Target property threshold operator. The target property settings of this operator allow you to nominate:
Sample values equal to or within the specified range of the target property are unchanged.
Echoview can display related single targets information using the TS substitution operator. Such information may be sourced from: