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Could continue adding elements tothe array

Although I won't demonstrate it, I can tell you that if I were to continue adding elements in this manner to increase the length of the array, the centralpeak and the peaks at the folding wavenumbers would continue getting narrower, and the trough between the peaks would continue getting deeper and probablyflatter.

A more selective wavenumber filter

In other words, when viewed as a wavenumber filter, a long array with more elements is a moreselective wavenumber filter than a short array with fewer elements. By properly designing an array to act as a wavenumber filter, it is possible to cause that filter to be veryselective.

When we use a properly designed array to produce a directional antenna, it is possible to produce a highly directional antenna (and avoid wasting our valuable radio frequency energy by sending it to cows and cotton plants).

A weighted three-element array

Continuing with our three-element array scenario, let's take a look at the center pair of images in Figure 3 and compare them with the leftmost images in Figure 3 .

For this case, the array still contains three elements with the same spacing as before. However, the electrical output from the center element is amplifiedto make it twice as strong as the outputs from the other two elements before the three electrical signals are added together.

Note that the array elements are no longer shown as being white against a black background in the very top of the top-center image. Instead, thecenter element is white but the other two elements are greenish indicating different weights.

It is a little hard to tell what this does to the central peak in the wavenumber response, but it definitely changes the shape of the response in thetrough between the peaks. Whether or not this would be a beneficial change would depend on the problem being addressed.

A three-element array with negative weighting

Finally, take a look at the rightmost pair of images in Figure 3 . Once again, the array contains three elements and the center element is weighted twice asheavily as the other two. In addition, the sign of the electrical signals from the two outer elements is inverted before the three are added together.

Note that the black color represents the smallest algebraic value. Negative values are smaller than positive values. Therefore, the background(which represents a weigh of zero) has changed from black to something between green and blue. The two elements withthe negative weights are shown as black and the element with the positive weight is shown as white.

The wavenumber response

This has a major impact on the wavenumber response of the three-element array.

There is no longer a peak at a wavenumber value of zero. Rather, there is now a null point at zero wavenumber as indicated by the black and blue colors at thecenter of the plot. There is now a peak on each side of zero (as indicated by the white and red colors) , half way between zero and the folding wavenumber.

Questions & Answers

what is the stm
Brian Reply
is there industrial application of fullrenes. What is the method to prepare fullrene on large scale.?
industrial application...? mmm I think on the medical side as drug carrier, but you should go deeper on your research, I may be wrong
How we are making nano material?
what is a peer
What is meant by 'nano scale'?
What is STMs full form?
scanning tunneling microscope
how nano science is used for hydrophobicity
Do u think that Graphene and Fullrene fiber can be used to make Air Plane body structure the lightest and strongest. Rafiq
what is differents between GO and RGO?
what is simplest way to understand the applications of nano robots used to detect the cancer affected cell of human body.? How this robot is carried to required site of body cell.? what will be the carrier material and how can be detected that correct delivery of drug is done Rafiq
what is Nano technology ?
Bob Reply
write examples of Nano molecule?
The nanotechnology is as new science, to scale nanometric
nanotechnology is the study, desing, synthesis, manipulation and application of materials and functional systems through control of matter at nanoscale
Is there any normative that regulates the use of silver nanoparticles?
Damian Reply
what king of growth are you checking .?
What fields keep nano created devices from performing or assimulating ? Magnetic fields ? Are do they assimilate ?
Stoney Reply
why we need to study biomolecules, molecular biology in nanotechnology?
Adin Reply
yes I'm doing my masters in nanotechnology, we are being studying all these domains as well..
what school?
biomolecules are e building blocks of every organics and inorganic materials.
anyone know any internet site where one can find nanotechnology papers?
Damian Reply
sciencedirect big data base
Introduction about quantum dots in nanotechnology
Praveena Reply
what does nano mean?
Anassong Reply
nano basically means 10^(-9). nanometer is a unit to measure length.
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
for teaching engĺish at school how nano technology help us
How can I make nanorobot?
Do somebody tell me a best nano engineering book for beginners?
s. Reply
there is no specific books for beginners but there is book called principle of nanotechnology
how can I make nanorobot?
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.
how did you get the value of 2000N.What calculations are needed to arrive at it
Smarajit Reply
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