Calculating the angles from Complex data for Beam Type: 97
The split-beam angles, angles for short, can be calculated based on the output angle information included in the Sample binary
datagram. Use the beam type of the transducer and the type of angle information in the datagram (Complex or Angle) to determine the right processing of the angle data
This section describes the steps involved in calculating the angles for the EC150–3C transducer. The angle data in the Sample binary datagram is Complex. The parameter Beam Type will identify the transducer geometry and type. The Beam Type for this transducer is provided in the raw file.
| • | Beam Type:97 |
The beams from the transducer is numbered and named according to the numbering in the user interface.
| 1 | Fore Starboard |
| 2 | Aft Port |
| 3 | Aft Starboard |
| 4 | Fore Port |
Complex values are retrieved from the Sample binary datagram. These are the real and imaginary parts of the electrical voltage output for each of the individual receiver channels, also
referred to as ADCP beams. SEC1 refers to 1 — Fore Starboard and so on.
Temporary angles are calculated using these x and y values.
The arctan2 is expanded for giving results in the following range: <-Π, Π].
Note
Use the section Implementation of arctan for implementation details.
Λ is the Angle Sensitivity. This information is normally given in the data sheet for the product. The angle sensitivity is retrieved from the Configuration XML datagram.
Some more mathematics and the split-beam angles are given by the following equation.
Place the result from this equation:
| • | Ψ=45° |
The angles (Ux) and (Uy) is calculated using the result from the previous equation.
