Tool/software:
Thank you in advance for your assistance.
I am working on an Ultrasonic Flow Metering/Detection application. I am using the ProComm 1 MHz Transducers that are the Clamp On Style on the outside of 3/8" Polyethylene Tubing. The transducers are in W configuration so I do have the gain maxed out at 30.8 dB to get the signal through the tubing and water. I started with a Frequency Sweep for my excitation Frequency. I adjusted the # of Pulse, Capture Start, and Capture Duration. I then say the Envelope Threshold. Here are my parameters and ADC Capture when pressing the "Capture" button.
However when I look at the Waveform Capture, I'm getting a lot a +/-10 uSecond erratic readings.
When getting these large dToF values, I was not getting any errors so looking at the forum, I saw, Cycle Slipping, that is similar to what I'm seeing so I did change the code to USS_ALG_MAX_RATIO_PEAK_2_PEAK_VAR 0.0, recompiled, flashed to the micro and retested. This made no difference in the results. I looked at the signals on with the o-scope, I did solder small lengths of wires onto the backside of the Dev Board to make it easier to capture the signal. I do see some noise on the lines so I have have tried to isolate the board as much as possible but don't see much else wrong with the signals (the amplitude could be higher but without the addition of external amplifiers I don't this that is feasible right now).
The noise is moving with each waveform capture. Still seeing the same results. I started to look at the ADC Capture to see if I can see a correlation of noise with the Cycle Slip on the ADC Capture. When using the Capture button, I was unable to see any slipping or offsets but everything looked the same. I then did a "Continuous Capture" and was able to capture a few ADC captures like this:
This seems to be happening randomly, but I have not been able to identify the reason (possible noise throwing off the Lobe Algorithm). I know +/- 900 ADC counts is ideal but SLAU810B states "the system should be operable with signals down to +/-150 ADC Counts" so I think the signal strength is sufficient and I have the DC Offset Cancelation enabled to "center" my ADC around Zero so I would have a ~+/625 ADC Count.
Can someone confirm that this is a cycle slip and if so any suggestions to prevent or minimize their occurrence? I do what sometimes the UPS and DNS are the same shape as each other but a 20-30 ADC Count difference not as often and I could not capture that in screen shot before the next capture over-wrote the waveform.
