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A big request for clearing this simple doubt. For an application, I am using antenna arrays(say dipoles and array length is 11 elements). Now, this antenna array will have the beamforming vectors based on the users distance and angle which I calculate using triangulation. I have a few questions on this.

1st question:

Now, that I know user's distance from the antenna, and I know I need to cast my beam onto the user who is at a distance d, I need to adjust my weights of the antenna. The steering angle I give the input from triangulation and get it and the beam rotates in angle. Now, I want to reduce the amplitude of the beam. Can the user distance in meters from the base station be considered directly for the amplitude of the beam ? If not, how can we convert the user distance to the amplitude required for the beam to just cover the user(user should always be in the tip of the beam)

2nd question:

I am also thinking on power saving. I assume that every antenna element will be fed with a current "I". I would like to know the equations(if they exist) for the changes in array weights for a specific user using beamforming, I should be able to get a relation with reduced current values. Because, If the user is close to the base station, I will have a lessen the gain and I will need lesser current for each element for supporting that gain. Is this theory right ?

3rd question:

suppose for a case, weight for one of the antenna array element is 1 and and for another element is 0.5 so is this relation true ? I (w=1) = 2 x I(w=0.5)

Please help me out !

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  • \$\begingroup\$ I have a jargon or nomenclature problem here. 1) By weight, do you mean signal phase? 2) By triangulation do you mean you find the angle by some means other than the antenna? 3) Is your steering angle from rotating the array elements, rotating the whole array, or phased array steering? \$\endgroup\$ – C. Towne Springer Apr 1 '14 at 5:39
  • \$\begingroup\$ Thanks for the comment, 1) By weight, I mean the adjusted antenna array weights for the signal received angle and distance of the user. 2) Yes, I find the angle from base station to the mobile user with the help of matlab "triangulation" and "dsearchn" to get the nearest user to the base station and the angle between him and the base station and the distance. 3) weights by progressive phase, ascan(n) = a(n) * exp(-j*(n-(N-1)/2)*ps0), n = 0,1,...,N-1 \$\endgroup\$ – user3222664 Apr 1 '14 at 9:42
  • \$\begingroup\$ I see. Are you using a book or online tutorial? I would need to see the derivation that uses the complex exponential form of the phases and angles. By the way, you can install Greasemonkey/MathJax in your browser and use LaTex in your questions and comments. Just put double dollar signs around your LaTeX. Something like this I think, which is easier for us old school types to read. $$ ascan_{n} = a_{n} e^{\left( -j\left( n-\frac{\left( N-1 \right)}{2} \right)ps0 \right)},\; n\; =\; 0,1,...,N-1\; – $$ \$\endgroup\$ – C. Towne Springer Apr 2 '14 at 5:23
  • \$\begingroup\$ Thank you. Sure. Yes, I am using the following ebook. Please help me out.google.co.in/… \$\endgroup\$ – user3222664 Apr 2 '14 at 10:18

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