Simrad and Echoview single target detection terminology
This topic is a general reference about matching Simrad and Echoview terminology. It assumes familiarity with the single target detection algorithm and an understanding of its function. It specifically provides a guide for the comparison of terminology, units and values between the settings on the ER60 software's Single target detection dialog box and the settings on the Single target detection page of Variable properties dialog box in Echoview. The terminology applies equally to all Ex500, EK80, and Ex60 series echosounders.
Simrad Ex60 series terminology is taken from the Simrad ER60 Operator Manual (850-164692/Rev. A), pages 109 and 110. Simrad EK80 series terminology is taken from the Simrad EK80 Wide band scientific echo sounder Reference Manual found here. Simrad Ex500 series terminology is taken from the Simrad EK 500 Operator Manual (P2170E, Software Version 4.01 September 1993), Operation section, pages 69-71. Where Ex60, EK80 and Ex500 series nomenclature differs this is denoted in the table below.
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Simrad terminology
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Echoview terminology
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Units
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Notes
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Min. Threshold (Ex60, EK80) |
TS threshold |
(dB)
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Min. Echo Length |
Minimum normalized pulse length |
(unitless)
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Simrad's echo length calculation is always performed using a Pulse length determination level of 6 dB. Echoview's Pulse length determination level (6 dB or otherwise) is entered on the Single target detection page of the Variable properties dialog box in Echoview. |
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Max. Echo Length |
Maximum normalized pulse length |
(unitless) | |
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Max. Phase Deviation |
Maximum standard deviation of Minor axis angles and Maximum standard deviation of Major axis angles |
Simrad: (phase steps) For the relationship between Simrad's phase steps and Echoview's mechanical degrees see Simrad angular position calculations.
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Simrad apply the same Max. phase deviation to both major and minor axes, Echoview allows you to specify them independently. |
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Max. Gain Comp. |
Maximum beam compensation |
(dB)
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Simrad's Max. gain comp. applies to one-way gain. Echoview's Maximum beam compensation applies to two-way gain. So to have the same effect, Max beam compensation on the Single target detection page of the Variable properties dialog box should be set to double the Max. gain comp. value in the ER60. In other words: Maximum beam compensation = 2 × Max. gain comp. |
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Beam compensation model |
Echoview provides a choice of beam compensation models. The ER60 does not. Use the Simrad LOBE beam compensation model on the Single target detection page of the Variable properties dialog box if you wish to replicate the ER60's. |