Acoustic Vector Sensors Notes SP2010
Team Members: Evan
PhD Supervisor: Satya, Murat
Faculty Supervisor: Arye Nehorai
Contents
Goals
Understanding the AVS response:
- To compute the frequency response and identify the bandwidth with flat response in all the channels.
- To study the effects of the equalizer on the velocity measurements.
Perform 3D real-time source location using the four AVS
- Revise the GUI
- Implement an efficient method for triangulation in 3D
Status
Week 1 (1/25 and 1/27)
This week we worked out minor bugs in code and got everything back to where we left off last semester. The echo problem is still present. We discussed different ways to fix this problem. The assumptions that we made for the Capon spectrum to work may not be accurate (far field vs. near field acoustic waves)
Week 2 (2/1 and 2/3)
We gathered data from an AVS and compared it to the data we generate from the simulated data. The simulated data has the different components of the sensor in phase while the actual collected data did not. We altered the simulation to make the waves out of phase and observed the same 'echo' effect that we experience in the real data. This may be the source of the echo in the real data. Next week we will try to find a way to get the real data in phase.
Week 3 (2/8 and 2/10)
This week we developed a MATLAB script to correct the phase difference in the data. On Wednesday we finished the script and tested it on our phase shifted simulation. The script worked and lessened the echo to roughly 1/4 the magnitude of the real peak. Some LabView bugs made it difficult to continue working with the program, but hopefully they will resolve themselves when we switch computers. Next week we will attempt to apply the script to the real data- hopefully it will remove the echo that we previously experienced.
Week 4 (2/15 and 2/17)
We are still having a lot of trouble working out the problems with LabView. Sometimes matlab scripts which are changed while LabView is open do not cooperate and update well. We are trying to work past this. We are expanding the matlab script which removes the phase difference to shift multiple sets of data- hopefully in the near future this will be complete and we can test out our script on real data.
Week 5 (2/22)
Today we had promising progress with LabView- we now have the simulation for two sensors working again, although phase shifts to the data sometimes does not effect the right component of our estimated direction of arrival. More on Wednesday.
Files
Here are the files that we use. Note that the MATLAB files are in a .zip file because the wiki will not allow me to upload .m files.
