SonTek Recommended Checks

• Signal-to-Noise Ratio - Verify that SNR is at least 3 dB throughout profile and that it decays as expected with distance.
• Acoustic Signal Amplitude - Verify that signal amplitude (the strength of the acoustic signal) follows a similar pattern as SNR.
• Noise Level - Verify that the noise floor is at an acceptable range for specific system type.
• System Hardware Configuration - Verify that the specific system was appropriate for the data requirements (e.g. that a long-range profiler was not installed downlooking at 1m above the bed).
• User Setup Configuration - Verify that the system was properly configured for data requirements (e.g. that the wave burst is long enough).
• Deployment Duration - Verify that length of record is as expected.
• Temperature/Pressure Data - Verify that these “environmental” parameters behaved as expected. For example: a) that neither read zero or values too high/low, b) that their fluctuation during deployment is comparable to the known or expected site conditions, and c) no outliers are present.
• Compass Data - Verify that the three compass components (heading, pitch and roll) remain within the compass’ accuracy range. Also, verify that the system was stationary during the deployment.
• Power Level - Verify that battery or power input was supplying acceptable voltage to system throughout deployment.
• Range to Surface - Verify that the range to surface, as estimated by the SNR profiles, matches those reported by the pressure sensor.
• Standard Error - Verify that the standard error of velocity is within acceptable ranges.
• Ambiguity Jumps - Check data for times when maximum velocity exceeds upper limit for pulse-coherent systems and ambiguity jumps occur (“velocity wrapping”). If necessary, apply software-based ambiguity resolution correction when applicable.
• Velocity Range - Verify that, for an ADV and Triton, the velocity range chosen was appropriate. For Tritons, check whether auto-velocity was used.