Along-beam bin center separation

[PLACEHOLDER -- NEED TO CONFIRM THIS IS CORRECT AND/OR ADD PICTURE]

For ADCPs, the [math]\displaystyle{ Z }[/math]-axis in instrument coordinates is commonly defined along the axis of the ADCP pressure case. The velocity data are commonly given in terms of this [math]\displaystyle{ Z }[/math]-coordinate. For a vertical beam, the along beam bin center separation ([math]\displaystyle{ r_0 }[/math]) is given by:

[math]\displaystyle{ r_0 = z }[/math]

where [math]\displaystyle{ z }[/math] is the distance from the transducer along the [math]\displaystyle{ Z }[/math]-axis.

For diverging beams, the along beam bin center separation ([math]\displaystyle{ r_0 }[/math]) is given by:

[math]\displaystyle{ r_0 = \frac{z}{\cos\theta} }[/math]

where [math]\displaystyle{ \theta }[/math] is the angle of the diverging beams with the [math]\displaystyle{ Z }[/math]-axis.