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ices-publications / SONAR-netCDF4

The SONAR-netCDF4 convention for sonar data
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1. Clarify the definition of the effective pulse length. #3

Closed lberger29 closed 4 years ago

lberger29 commented 4 years ago
  1. Clarify the definition of the effective pulse length.
  2. Suppress the Sacorr parameter which is Simrad specific and has recently lead to confusion with EK80 (difference between Sacorr and Sacorr_adjust)
  3. Modify equation type 3 for Sv calculation
gavinmacaulay commented 4 years ago

Equation type 3 is intended for EK60, ES60, and ES70. So just CW and where it is fairly clear what the Sa correction is (type 4 is for the EK/ES80 where the confusion occurs).

lberger29 commented 4 years ago

The goal was also to have only two parameters in the format for pulse duration (nominal transmit and calibrated receive effective pulse length) and use the calibrated effective term in Equation 3 as for the calibrated Gain G0 We would then be consistent between equation 1 and 3 for all Simrad sonars. Keeping Sa correction for EK60 still means that we have to compute calibrated receive effective pulse length for filling the existing parameter of the format and this value can then be used directly in equation 3.

gavinmacaulay commented 4 years ago

ok, I understand now. I'm still a bit nervous about deviating from the equation that everyone knows to use for the EK60. Perhaps if we show how to go from Sacorr to t_e?

lberger29 commented 4 years ago

I agree, that's why I have added the transformation from tau to tau_e using Sacorr in equation 3