On 17 Feb, 22:15, Glen Herrmannsfeldt <g...@ugcs.caltech.edu> wrote:> Tim Wescott wrote: > > (snip) > > > I can think of > > four likely possibilities of what may happen: one, he or she is waiting > > for your questions, ready to give you guidance (not answers, mind -- > > guidance); two, he or she is severely overworked, and can't help (in > > which case you picked the wrong school, and we'll try to help); three, he > > or she isn't interested in doing his/her job and _won't_ help (in which > > case you or your school picked the wrong prof, and you may be able to > > switch); finally, you're being too needy, and your prof is trying to push > > you out of your comfort zone so you'll succeed in the real world (this > > can be hard to tell from three from inside your own head -- ask your > > friends, and review my comment about the word "thesis"). > > There is also five: > > Prof doesn't know, but would find the answer useful in his research. > (I will guess that women wouldn't try this.) �When they get the answer, > it will end up in a published paper with his name on it. > > I have heard that this happens much more often that it should.I suppose that's how the world works these days: Professor runs deparmtent (presumably) overseeing work; PhD student runs day-to-day tutoring and supervising of students; students to hands-on work. The prof needs his name on the paper to reap the financial rewards when inventories are counted at end-of-year. The others want their names on the paper because they did the work. Where I used to work, all three persons got their name on the paper as co-authors. No one had any problems with that. The problems occur when somebody are left out. Rune

# Sound Localization Matlab, Please Help!

Started by ●February 17, 2009

Reply by ●February 18, 20092009-02-18

Reply by ●February 25, 20092009-02-25

Thank you for all your responses. In fact, the situation is that my supervisor is the head of my department, and has no time to meet me, and as such, I am lost! Your responses have allowed me to revise my original post, and I have realised that the problem wasn't that clear. I have only two microphones, and yes, I am in control of the sound. What I am trying to implement is a sound intensity probe. Since my original post, I have made some advances. I have done some recordings in a field, so no errors occur. The microphones are held in a constant position whilst recording. In each recording, the angle of arrival of the sound is different (i.e. I have moved the sound source to a different location on a circle of the same radius.) When I analyse the data, I've plotted a graph of the phase versus the frequency. The resulting graph is somewhat of a cut-saw image, such as: /|/|/| Excuse the crudeness of this diagram, it was the best I could do from the characters on the keyboard! The slope of this graph should give me some information about the sound location, and I should be able to experimentally determine the angle of arrival, and the distance from the two mics. I have used the fuction tfestimate in MATLAB, and the angle of the Tf for the phase. I am somewhat confused as to how to work out the distance and angle, could someone please clear it up!

Reply by ●February 25, 20092009-02-25

staplep wrote:> Thank you for all your responses. In fact, the situation is that my > supervisor is the head of my department, and has no time to meet me, and as > such, I am lost! Your responses have allowed me to revise my original post, > and I have realised that the problem wasn't that clear. I have only two > microphones, and yes, I am in control of the sound. What I am trying to > implement is a sound intensity probe. > > Since my original post, I have made some advances. I have done some > recordings in a field, so no errors occur. The microphones are held in a > constant position whilst recording. In each recording, the angle of arrival > of the sound is different (i.e. I have moved the sound source to a > different location on a circle of the same radius.) When I analyse the > data, I've plotted a graph of the phase versus the frequency. The resulting > graph is somewhat of a cut-saw image, such as: > > /|/|/| > > Excuse the crudeness of this diagram, it was the best I could do from the > characters on the keyboard! The slope of this graph should give me some > information about the sound location, and I should be able to > experimentally determine the angle of arrival, and the distance from the > two mics. > > I have used the fuction tfestimate in MATLAB, and the angle of the Tf for > the phase. I am somewhat confused as to how to work out the distance and > angle, could someone please clear it up!The phase illustration is typical of wraparound, the calculated phase being confines to "principal value", while the real phase can accumulate forever. Jerry -- Engineering is the art of making what you want from things you can get. �����������������������������������������������������������������������