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| {{About|side lobes in antenna engineering|side lobes in digital signal processing|spectral leakage}}
| | He'll also want to know where you are and what you're doing. Yet even in the darkest of scenarios, there's still some light at the end of the tunnel. He'll want to know what you're up to and why you suddenly dropped off the face of the earth and didn't fight for the relationship. Avoid using an old text that you sent them before because it will not work. Combine these three tips with the rest of a time tested formula for getting your ex back into your arms and you will be able to build yourself up while building up what could be a lasting relationship with the man of your dreams. <br><br>One has to fully accept the breakup since without this anyone can never revert back to the path of reconciliation. Keep in touch by sending light hearted text messages and making less frequent phone calls. This week: Dear Abiola, Should I Try To Get Back Together With My Ex. And for a list of signs that your ex wants you back, visit Winning Your Ex Back. I hope that during your no contact period that you've improved as a person both physically and mentally. <br><br>For now, just keep advancing until you get a front row seat for an execution. These people end up getting back together and giving things another shot, because they loved and missed each other - and the times they shared. It takes a long time to establish a deep connection so it only makes sense that it would take a long time to untangle the connection. Lastly - and one of the most effective ways to create jealousy - is simply to be as social as possible. In time, he will come to realize what he's lost in you, and this will work out well in your efforts to get him back. <br><br>His web page has by significantly the best data out there, for a fraction of the price tag that some folks are charging. I am going to put far more effort into dressing up for him for a great night out. Once a man realizes that you are perfectly ok without him, he begins to wonder if there is something valuable that he has lost. This of course is very destructive for all parties involved and another down fall of not trying to get back with an ex before moving on to a new relationship. With the above techniques, you can really effectively say "Now, I know the very best way to win back my ex. <br><br>Show her how much you miss her, and how sorry you are. You'll give yourself the preferred chance of getting back closely with that special someone. If your ex withdraws away from you, then it is a sign that you need to work harder. Word just may get back to your partner that you're out having fun without her. One of the most obvious methods of showing that you want to win back your boy or girl is by constantly telling him or her that you are still single.<br><br>If you have any queries concerning wherever and how to use [http://www.kok1235.info/ get ex boyfriend back], you can get in touch with us at our own internet site. |
| {{unreferenced|date=April 2008}}
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| [[File:Sidelobes en.svg|thumb|A typical [[directional antenna]] radiation pattern in [[polar coordinate system]] representation, showing side lobes. The radial distance from the center represents signal strength.]]
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| [[File:Typical Antenna Pattern.jpg|thumb|250px|A typical antenna radiation pattern in [[cartesian coordinate system]] representation showing side lobes.]]
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| {{Antennas|Radiation sources and regions}}
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| In [[Antenna (radio)|antenna]] engineering, '''side lobes''' or '''sidelobes''' are the lobes (local maxima) of the [[Near and far field|far field]] [[radiation pattern]] that are not the [[main lobe]].
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| The radiation pattern of most antennas shows a pattern of "''lobes''" at various angles, directions where the radiated signal strength reaches a maximum, separated by "''[[null (radio)|null]]s''", angles at which the radiated signal strength falls to zero. In a [[directional antenna]] in which the objective is to emit the radio waves in one direction, the lobe in that direction has a larger field strength than the others; this is the "''[[main lobe]]''". The other lobes are called "''side lobes''", and usually represent unwanted radiation in undesired directions. The '''side lobe''' in the opposite direction (180°) from the main lobe is called the "''back lobe''". In [[Transmitter|transmitting]] antennas, excessive side lobe radiation wastes energy and may cause [[Electromagnetic interference|interference]] to other equipment. Classified information may be picked up by unintended receivers. In [[Radio receiver|receiving]] antennas, side lobes may pick up interfering signals, and increase the noise level in the receiver.
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| The power density in the side lobes is generally much less than that in the main beam. It is generally desirable to minimize the sidelobe level (SLL), which is measured in [[decibel]]s relative to the peak of the main beam. The main lobe and side lobes occur for both conditions of transmit, and for receive. The concepts of main and side lobes, radiation pattern, aperture shapes, and aperture weighting, apply to [[optics]] (another branch of electromagnetics) and in [[acoustics]] fields such as [[loudspeaker]] and [[sonar]] design, as well as antenna design.
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| For a rectangular aperture antenna having a uniform amplitude distribution (or uniform weighting), the first sidelobe is -13.26 dB relative to the peak of the main beam because for such antennas the radiation pattern has a [[canonical form]] of
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| <center> | |
| <math> | |
| \displaystyle\mbox{Radiation Pattern (in units of dB)} \propto 20\log_{10}\left(\left|\frac{\sin(X)}{X}\right|\right)
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| </math>
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| </center>
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| Simple substitutions of various values of <math>\displaystyle X</math> into the canonical equation yield the following results:
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| <center>
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| {| class="wikitable"
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| |-
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| ! <math>\displaystyle X</math>
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| ! Radiation Pattern
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| ! Explanation
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| |-
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| | <math>\displaystyle 0</math>
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| |align=right| <math>\displaystyle0~\mbox{dB}</math>
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| | peak of main beam
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| |-
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| | <math>\displaystyle 3.14=\pi</math>
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| |align=right| <math>-\infty~\mbox{dB}</math>
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| | first null
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| |-
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| | <math>4.49\approx\frac{3\pi}{2}</math>
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| |align=right| <math>\displaystyle-13.26~\mbox{dB}</math>
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| | peak of first sidelobe
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| |-
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| | <math>\displaystyle 6.28=2\pi</math>
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| |align=right| <math>-\infty~\mbox{dB}</math>
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| | second null
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| |-
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| | <math>7.72\approx\frac{5\pi}{2}</math>
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| |align=right| <math>\displaystyle-17.83~\mbox{dB}</math>
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| | peak of second sidelobe
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| |}
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| </center> | |
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| For a circular aperture antenna, also having a uniform amplitude distribution, the first sidelobe level is -17.57 dB relative to the peak of the main beam because in this case, the radiation pattern has a [[canonical form]] of | |
| <center>
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| <math>
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| \displaystyle\mbox{Radiation Pattern (in units of dB)} \propto 10\log_{10}\left(\left|2\frac{J_1(X)}{X}\right|^2\right)
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| </math>
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| </center>
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| where <math>\displaystyle J_1(x)</math> is the [[Bessel function of the first kind]] of order 1. Simple substitutions of various values of <math>\displaystyle X</math> into the canonical equation yield the following results:
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| <center>
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| {| class="wikitable"
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| |-
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| ! <math>\displaystyle X</math>
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| ! Radiation Pattern
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| ! Explanation
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| |-
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| | <math>\displaystyle 0</math>
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| |align=right| <math>\displaystyle0~\mbox{dB}</math>
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| | peak of main beam
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| |-
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| | <math>\displaystyle 3.83</math>
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| |align=right| <math>-\infty~\mbox{dB}</math>
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| | first null
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| |-
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| | <math>\displaystyle5.14</math>
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| |align=right| <math>\displaystyle-17.57~\mbox{dB}</math>
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| | peak of first sidelobe
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| |-
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| | <math>\displaystyle7.02</math>
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| |align=right| <math>-\infty~\mbox{dB}</math>
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| | second null
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| |-
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| | <math>\displaystyle8.42</math>
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| |align=right| <math>\displaystyle-23.81~\mbox{dB}</math>
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| | peak of second sidelobe
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| |}
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| </center>
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| A uniform aperture distribution, as provided in the two examples above, gives the maximum possible [[directivity]] for a given aperture size, but it also produces the maximum side lobe level. Side lobe levels can be reduced by tapering the edges of the aperture distribution (changing from uniformity) at the expense of reduced [[directivity]].
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| The nulls between sidelobes occur when the radiation patterns passes through the origin in the [[complex plane]]. Hence, adjacent sidelobes are generally 180° out of phase to each other.
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| Because an antenna's [[far field]] [[radiation pattern]] is a [[Fourier Transform]] of its aperture distribution, most antennas will generally have sidelobes, unless the aperture distribution is a [[Normal distribution|Gaussian]], or if the antenna is so small, as to have no sidelobes in the visible space. Larger antennas have narrower main beams, as well as narrower sidelobes. Hence, larger antennas have more sidelobes in the visible space (as the antenna size is increased, sidelobes move from the [[Evanescent wave|evanescent space]] to the [[visible space]]).
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| [[File:Typical antenna pattern with grating lobes.jpg|thumb|250px|A typical [[radiation pattern]] of [[phased array]]s whose inter-element spacing is greater than half a wavelength, hence the radiation pattern has grating lobes.]]
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| For discrete aperture antennas (such as [[phased array]]s) in which the element spacing is greater than a half wavelength, the spatial [[aliasing]] effect causes some sidelobes to become substantially larger in amplitude, and approaching the level of the main lobe; these are called [[grating lobe]]s, and they are identical, or nearly identical in the example shown, copies of the main beams. Grating lobes are a special case of a sidelobe. In such a case, the sidelobes should be considered all the lobes lying between the main lobe and the first grating lobe, or between grating lobes. It is conceptually useful to distinguish between sidelobes and grating lobes because grating lobes have larger amplitudes than most, if not all, of the other side lobes. The mathematics of grating lobes is the same as of [[X-ray diffraction]].
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| == External links ==
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| *[http://www.antenna-theory.com/basics/radPatDefs.php Sidelobes and Beamwidths - An Antenna Tutorial]
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| [[Category:Antennas]]
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| [[Category:Radio frequency propagation]]
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| [[de:Antennendiagramm#Elemente eines Antennendiagramms]]
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He'll also want to know where you are and what you're doing. Yet even in the darkest of scenarios, there's still some light at the end of the tunnel. He'll want to know what you're up to and why you suddenly dropped off the face of the earth and didn't fight for the relationship. Avoid using an old text that you sent them before because it will not work. Combine these three tips with the rest of a time tested formula for getting your ex back into your arms and you will be able to build yourself up while building up what could be a lasting relationship with the man of your dreams.
One has to fully accept the breakup since without this anyone can never revert back to the path of reconciliation. Keep in touch by sending light hearted text messages and making less frequent phone calls. This week: Dear Abiola, Should I Try To Get Back Together With My Ex. And for a list of signs that your ex wants you back, visit Winning Your Ex Back. I hope that during your no contact period that you've improved as a person both physically and mentally.
For now, just keep advancing until you get a front row seat for an execution. These people end up getting back together and giving things another shot, because they loved and missed each other - and the times they shared. It takes a long time to establish a deep connection so it only makes sense that it would take a long time to untangle the connection. Lastly - and one of the most effective ways to create jealousy - is simply to be as social as possible. In time, he will come to realize what he's lost in you, and this will work out well in your efforts to get him back.
His web page has by significantly the best data out there, for a fraction of the price tag that some folks are charging. I am going to put far more effort into dressing up for him for a great night out. Once a man realizes that you are perfectly ok without him, he begins to wonder if there is something valuable that he has lost. This of course is very destructive for all parties involved and another down fall of not trying to get back with an ex before moving on to a new relationship. With the above techniques, you can really effectively say "Now, I know the very best way to win back my ex.
Show her how much you miss her, and how sorry you are. You'll give yourself the preferred chance of getting back closely with that special someone. If your ex withdraws away from you, then it is a sign that you need to work harder. Word just may get back to your partner that you're out having fun without her. One of the most obvious methods of showing that you want to win back your boy or girl is by constantly telling him or her that you are still single.
If you have any queries concerning wherever and how to use get ex boyfriend back, you can get in touch with us at our own internet site.