Matlab Programs about Antenna Theory

can u send me the matlab code to srikanth_joshi2k6@yahoo.co.in plz ..urgent

hi friend
any body have matlab code for two arm archimedean spiral antenna.

plz can you send it to kallyany@gmail.com

thank you

hi ... i have to generate radiation patterns for a dipole using closed form equations in matlab and i have the equations.

the equation for radiation pattern are in balanis for Eθ

ive attached the equation for Eθ please help me to plot this equation to getthe radiation pattern. ive done some matlab code but it says matlab dimensions does not agree. dont know how to do .....

code :
n=376; % intrinsic impedence %
c=3*10^8;
f=2*10^9; % frequency
lamida=c/f;
k=(2*pi)/lamida; % wave number
Io=1; % current
r=18; % range length

delta=.01*lamida+0.0035; %displacement factor

e=exp(-j*k*r);


for
thetaa=1:1:360
E(thetaa)=(j*n)*((Io*e)/(2*pi*r))*((cos(k*delta)*cos((pi/2)*cos(thetaa))+sin(k*delta)-(sin(k*delta)*cos(thetaa)*sin((pi/2)*cos(thetaa))))/sin(thetaa));
end
polar(thetaa,E(thetaa));






equations are

https://obrazki.elektroda.pl/8_1281508293.jpg

Added after 2 minutes:

hi ... i have to generate radiation patterns for a dipole using closed form equations in matlab and i have the equations.

the equation for radiation pattern are in balanis for Eθ

ive attached the equation for Eθ please help me to plot this equation to getthe radiation pattern. ive done some matlab code but it says matlab dimensions does not agree. dont know how to do .....

code :
n=376; % intrinsic impedence %
c=3*10^8;
f=2*10^9; % frequency
lamida=c/f;
k=(2*pi)/lamida; % wave number
Io=1; % current
r=18; % range length

delta=.01*lamida+0.0035; %displacement factor

e=exp(-j*k*r);


for
thetaa=1:1:360
E(thetaa)=(j*n)*((Io*e)/(2*pi*r))*((cos(k*delta)*cos((pi/2)*cos(thetaa))+sin(k*delta)-(sin(k*delta)*cos(thetaa)*sin((pi/2)*cos(thetaa))))/sin(thetaa));
end
polar(thetaa,E(thetaa));






equations are

https://obrazki.elektroda.pl/8_1281508293.jpg


my email address : suntosh2i@yahoo.com
suntosh2i@gmail.com

Optimum design of 2D and 3D antenna arrays for wireless systems.am doing my 3rd year project on this

Can any one help me plzzzzz

Re: matlab antenna

Thankz a LOT

hey guys,

can someone send me the file for microstrip antennas in matlab at pavel_mc2@hotmail.it ??
I really need them and I cannot get the cd from my library...

Thanks a lot

Re: matlab avaxhome 2009

hello ,how to find snr for this program array_factor_1136.doc (20.5 KB) Can anyone help me

Re: matlab avaxhome 2009

SNR is your signal to noise ratio. You need more information to figure this out. The things you need are Bandwidth, incoming power, and overall antenna gain, as well as any losses or NF additions to the system in question.

The noise floor is dependent on thermal noise which is a function of kBT where k is Boltzmann's constant, B is your bandwidth, a T is the temperature of what the antenna is looking at. If you know this all you need is the Received signal strength of the signal you are looking for, this can be found if you know enough about what is transmitting by using Friis transmission equation, if you don't know about the transmitter than you either need volts / meter and run that with your antenna to get Received signal strength.

Once you have all this the difference between the noise floor (kBT) and your received signal strength is your SNR.

Hope this helps,
Babbage.

Hello, can anyone help me on how to find the amplitude and weightage for this program array_factor_1136.doc? Thank you

- - - Updated - - -

Hello, can anyone help me on how to find the amplitude and weightage for this program array_factor_1136.doc? Thank you

- - - Updated - - -

Hello, can anyone help me on how to find the amplitude and weightage for this program array_factor_1136.doc? Thank you

The amplitude of each individual element and the weighting of each individual element is An which is defined on line 16 of that code.

This program only looks at the phase difference of each element wrt the spacing of the elements in the array.

You will notice if you change An to 2 the gain doubles from 5 to 10, this same thing will happen if you keep An the same but double the number of elements (N) in the system.

Hope this helps,
Babbage

Thank you Mr Babbage.

I have to do the design of digital beamforming for transmitter. When transmitting, a beamformer controls the phase and relative amplitude of the signal at each transmitter, in order to create a pattern of constructive and destructive interference in the wavefront. Do you have any ideas on the matlab coding?

ira,

This is relatively simple to do. All you need to do is follow this example
https://www.antenna-theory.com/arrays/weights/uniform.php

I have changed the code to do what you are asking to do and now you have a scan angle and a weighting, there are more complicated ways to do this but this will work:
% Origional code from: Department of Engineering, University of Fukui
% Coded by Chan Sokthai (sokthai@msn.com)
% Edit by Babbage 10/30/2012

clear all;

% element numbers
N = 5;

% element spacing
d = 0.7;

% theta zero direction
% 90 degree for braodside, 0 degree for endfire.
Scan_angle = 90;

An = [.5,.7,1,.7,.5];
% An = [1,1,1,1,1]
j = sqrt(-1);
AF = zeros(1,360);

for theta=1:360

% change degree to radian
deg2rad(theta) = (theta*pi)/180;

%array factor calculation
for n=0:N-1
AF(theta) = AF(theta) + An(n+1)*exp(j*n*2*pi*d*(cos(deg2rad(theta))-cos(Scan_angle*pi/180))) ;
end
AF(theta) = abs(AF(theta));

end

% plot the array factor
polar(deg2rad,AF);

Hello everyone, I want to ask a question. I run the simulation of beampattern, and then I try to change the value of theta. But why when I check the weight of the element the value remain the same? For example: theta=60, w=0.0076 , phase= 45 then change theta=80 , w=0.0076, phase=172.
Wasn't the weight should change too? Please help me. Thank you.

Hello,
Does anybody here have the design of simple beamforming system for transmitter? I already have the coding to generate the radiation pattern but I have to implement the coding into digital beamforming system. Can anybody here help me please. Thank you.

Re: matlab avaxhome 2009

hi can anybody help me to make a code for signal detection for direction finding
....

Re: antenna theory book download

If u dont have WinRar software install it, OR is it asking some password ?? Which file are u talking about ??