ADCP Bin Depth Transducer Offset

Compute ADCP beam-range bin centers on positive-down depths and caller bottom-clearance screen for a vertical instrument; side-lobe contamination and attitude corrections are not modeled.

Description

ADCP bins occupy beam ranges whose vertical projection depends on beam angle.

ADCP bins occupy beam ranges whose vertical projection depends on beam angle. Bin centers differ from their near edges.

Compute ADCP beam-range bin centers on positive-down depths and caller bottom-clearance screen for a vertical instrument; side-lobe contamination and attitude corrections are not modeled.

When to use ADCP Bin Depth Transducer Offset

Use this tool to compute ADCP beam-range bin centers on positive-down depths and caller bottom-clearance screen for a vertical instrument; side-lobe contamination and attitude corrections are not modeled.

Gather the water, wave, current or profile observations and any supplied calibration constants. Confirm units and the stated coordinate and pressure conventions.

How to use ADCP Bin Depth Transducer Offset and understand its results

Gather the water, wave, current or profile observations and any supplied calibration constants. Confirm units and the stated coordinate and pressure conventions.
Enter transducerDepthM, firstBinNearEdgeRangeM, binWidthM, binIndexes, beamAngleFromVerticalDegrees, downwardLooking, bottomDepthM, minimumBottomClearanceM using the field table and calculation rules, then run the tool.
Read binCenterDepthsM, callerUsableBinFlags. The explanation below defines the units, signs, ordering and any flags or placeholder values.
If the tool reports an input issue, correct the values and run it again. Apply the stated assumptions when interpreting a successfully returned result.

Input field	Meaning	Value type; see rules below	Requirement
transducerDepthM	Transducer depth m	number	Required
firstBinNearEdgeRangeM	First bin near edge range m	number	Required
binWidthM	Bin width m	number	Required
binIndexes	Bin indexes	list of number	Required
beamAngleFromVerticalDegrees	Beam angle from vertical degrees	number	Required
downwardLooking	Downward looking	boolean	Required
bottomDepthM	Bottom depth m	number	Required
minimumBottomClearanceM	Minimum bottom clearance m	number	Required

Use nonnegative zero-based integer indices, positive width, nonnegative ranges/depths/clearance and angle in [0,90). Require bottom at or below transducer. Down-looking adds depth; up-looking subtracts. Flag centers within surface and clearance limits with rounding allowance.^[1]

center depth = transducer depth ± (near-edge range + (index+0.5)width)cos(angle)

Units, indexing, boundary conditions and exceptional cases are defined in the calculation rules above.

Output field	Meaning	Value type
binCenterDepthsM	Bin center depths m	list of number
callerUsableBinFlags	Caller usable bin flags	list of number

json

{
  "input": {
    "transducerDepthM": 10,
    "firstBinNearEdgeRangeM": 5,
    "binWidthM": 2,
    "binIndexes": [
      0,
      1
    ],
    "beamAngleFromVerticalDegrees": 60,
    "downwardLooking": true,
    "bottomDepthM": 14,
    "minimumBottomClearanceM": 1
  },
  "output": {
    "binCenterDepthsM": [
      13,
      14
    ],
    "callerUsableBinFlags": [
      1,
      0
    ]
  }
}

Limitations and assumptions

Vertical attitude is assumed; side-lobe contamination and tilt corrections are excluded.

Numbers and computed results must be finite; overflow produces an error. Numeric lists are limited to 100,000 entries; the rules above may require smaller limits. Missing required fields, extra fields, wrong value types and violations of the calculation rules are input errors.

Alternative or Complementary methods

Use CTD Descend Rate Consistency Checker: Audit observed CTD signed descent rates and adjacent speed jumps against caller acquisition policy; flags do not automatically identify sensor lag or discard data. For a complementary task, use Subsurface Float Parking Pressure: Integrate layer-varying hydrostatic density into float parking pressure profiles, separating gauge dbar from absolute Pa; does not infer a neutral-buoyancy depth or use homogeneous pressure/depth division.

References

ADCP Bin Depth Transducer Offset — tool.io

Similar or alternative tools

CTD Descend Rate Consistency Checker
Audit observed CTD signed descent rates and adjacent speed jumps against caller acquisition policy; flags do not automatically identify sensor lag or discard data.
Subsurface Float Parking Pressure
Integrate layer-varying hydrostatic density into float parking pressure profiles, separating gauge dbar from absolute Pa; does not infer a neutral-buoyancy depth or use homogeneous pressure/depth division.