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The second part of the code uses the angles mentioned above to calculate the delay values, although again due to the regular nature of our array, it is possible to calculate only two of the delays outright and extrapolate the rest of the delays from those two. (Which is indeed what we have done in an effort to reduce calculations and make the algorithm more efficient.)

The final part of the code, not shown in the code above but which can be seen in the function node in the figure below, involves the recipropcal of those first two lines; that is, rescaling all the 'd' values found to 'k' values that can actually be used when shifting the signals prior to adding them together.

Delay generation vi

Sub-VI that, given the values 'k12' and 'k14', will generate the shifts (in indices) of the seven microphones (with the shift of microphone 1 assumed to be zero) and the angles theta and phi that the signal came from.

Main analysis vi

This is our top-end module, where all the modules mentioned in the previous section are brought together in the same vi and linked together in the proper ways so as to create a working project.

Main analysis vi

The culmination of our struggles with Labview 5.1, our top-end module which does ... well ... everything.

First, not unexpectedly, there is a call to the Waveform Generation VI , which provides us with our collected and upsampled signals. From that sub-VI, the signals from microphones 1, 2, and 4 are taken, microphones 1 and 2 passed to one for loop and 1 and 4 passed to the other. Within the for loop, as mentioned before, one signal is shifted relative to the other, and the norm taken, for all delay values possible. The result of this is concatenated into an array, the maximum norm found, and from the location of the maximum norm, the value of the delay, or as close as we can get with the sampling resolution we have.

These shift values (the integer index corresponding to as close as we can get to the ideal time delay) are passed to the Delay Generation VI , which then returns an array of values. The theta and pi values function as outputs to the front panel, and then the delay (shift) values are used to set the necessary shift for their corresponding microphone. Finally, the shifted output arrays are all summed (using a for loop, as a point by point summing module also seemed to be among those useful things not premade in Labview 5.1), and the output of the for loop, the array that is the sum of all the previous ones, is then attached to a waveform graph, also on the front panel.

An example result

As the titles state, the upper waveform is that of the first signal (unmodified in any way), and the second that of the final, delayed and summed signal. Note how the latter signal is somewhat smoother and the noise level reduced in comparison to the signal itself (a series of claps). The two numbers at the bottom correspond to the computer's calculation of what direction the signal is coming from.
Phi is measured such that straight up is at zero, along the xy plane at 90 degrees. Theta is measured with the "bottom" of the array (although it can of course be reoriented as the user pleases), that is, the negative y direction, as zero degrees. The signs of the angles indicate the direction of propagation of the wave, and are thus opposite to conventional intuition, and the sign of phi is, of course, impossible to determine with any degree of accuracy due to the up-down ambiguity inherent in a two-dimensional array.

Success! (For a deeper exploration of our results, please continue to the results module

Labview code

Questions & Answers

do you think it's worthwhile in the long term to study the effects and possibilities of nanotechnology on viral treatment?
Damian Reply
absolutely yes
how to know photocatalytic properties of tio2 nanoparticles...what to do now
Akash Reply
it is a goid question and i want to know the answer as well
characteristics of micro business
Do somebody tell me a best nano engineering book for beginners?
s. Reply
what is fullerene does it is used to make bukky balls
Devang Reply
are you nano engineer ?
fullerene is a bucky ball aka Carbon 60 molecule. It was name by the architect Fuller. He design the geodesic dome. it resembles a soccer ball.
what is the actual application of fullerenes nowadays?
That is a great question Damian. best way to answer that question is to Google it. there are hundreds of applications for buck minister fullerenes, from medical to aerospace. you can also find plenty of research papers that will give you great detail on the potential applications of fullerenes.
what is the Synthesis, properties,and applications of carbon nano chemistry
Abhijith Reply
Mostly, they use nano carbon for electronics and for materials to be strengthened.
is Bucky paper clear?
so some one know about replacing silicon atom with phosphorous in semiconductors device?
s. Reply
Yeah, it is a pain to say the least. You basically have to heat the substarte up to around 1000 degrees celcius then pass phosphene gas over top of it, which is explosive and toxic by the way, under very low pressure.
Do you know which machine is used to that process?
how to fabricate graphene ink ?
for screen printed electrodes ?
What is lattice structure?
s. Reply
of graphene you mean?
or in general
in general
Graphene has a hexagonal structure
On having this app for quite a bit time, Haven't realised there's a chat room in it.
what is biological synthesis of nanoparticles
Sanket Reply
what's the easiest and fastest way to the synthesize AgNP?
Damian Reply
types of nano material
abeetha Reply
I start with an easy one. carbon nanotubes woven into a long filament like a string
many many of nanotubes
what is the k.e before it land
what is the function of carbon nanotubes?
I'm interested in nanotube
what is nanomaterials​ and their applications of sensors.
Ramkumar Reply
what is nano technology
Sravani Reply
what is system testing?
preparation of nanomaterial
Victor Reply
Yes, Nanotechnology has a very fast field of applications and their is always something new to do with it...
Himanshu Reply
good afternoon madam
what is system testing
what is the application of nanotechnology?
In this morden time nanotechnology used in many field . 1-Electronics-manufacturad IC ,RAM,MRAM,solar panel etc 2-Helth and Medical-Nanomedicine,Drug Dilivery for cancer treatment etc 3- Atomobile -MEMS, Coating on car etc. and may other field for details you can check at Google
anybody can imagine what will be happen after 100 years from now in nano tech world
after 100 year this will be not nanotechnology maybe this technology name will be change . maybe aftet 100 year . we work on electron lable practically about its properties and behaviour by the different instruments
name doesn't matter , whatever it will be change... I'm taking about effect on circumstances of the microscopic world
how hard could it be to apply nanotechnology against viral infections such HIV or Ebola?
silver nanoparticles could handle the job?
not now but maybe in future only AgNP maybe any other nanomaterials
I'm interested in Nanotube
this technology will not going on for the long time , so I'm thinking about femtotechnology 10^-15
how did you get the value of 2000N.What calculations are needed to arrive at it
Smarajit Reply
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Source:  OpenStax, Investigation of delay and sum beamforming using a two-dimensional array. OpenStax CNX. Feb 04, 2006 Download for free at http://cnx.org/content/col10315/1.3
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