Pengaruh Jumlah Elemen Array Terhadap Speed Of Convergence Adaptive Beamforming Pada Smart Antenna

(1)

LAMPIRAN

clc;

close all;

clear all;

c= 300e6;

f= 800e6;

lambda = c/f;

d=lambda/2;

% INPUT DATA

A= input('masukkan jumlah array = ');

B= input('masukkan sudut sinyal datang (derajat)= ');

C= input('masukkan sudut interferensi(derajat) = ');

% TIME SETTINGS

sampel = 50; % Jumlah sampling

BitRate = 200;

% DATA YANG AKAN DIKIRIMKAN

theta = pi*[-1:0:1];

fsimulasi = 4*BitRate; %frekuensi simulasi

Ts = 1/fsimulasi; % periode simulasi

for k=1:sampel

q=randperm(2);

Data(k)=-1^q(1);

end

Data = upsample(Data, fsimulasi/BitRate);

t = Ts:Ts:(length(Data)/fsimulasi);

x=(cumsum(Data))/8;

% SINYAL INTERFERENSI

sinyal_interferensi = normrnd(0,1,1,length(t)).*exp

(j*(unifrnd(-pi,pi,1,length(t))));

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% RESPON ARRAY TERHADAP SUDUT DATANG DAN SUDUT INTERFERENSI

Kd = pi; %

respon_datang = zeros(1,A);

respon_interferensi = zeros(1,A);

for k = 0:A-1,

respon_datang(k+1) = exp(j*k*Kd*cos(B));

respon_interferensi(k+1) = exp(j*k*Kd*cos(C));

end;

% TOTAL SINYAL TERIMA

datang = zeros(A, length(t));

interferensi = zeros(A, length(t));

sinyal_terima =cos(pi*x)+j*sin(pi*x);

for i = 0:A-1,

datang(i+1,:) = sinyal_terima .* respon_datang(i+1);

interferensi(i+1,:) = sinyal_interferensi .* respon_interferensi(i+1); %

end;

total_sinyal = (datang + interferensi);

% HITUNG BEBAN UNTUK ARAH YANG DIINGINKAN

y = zeros(1,length(t)); % output

mu = 0.05; % step size

e = zeros(1,length(t)); % error

w = zeros(1,A); % weights

for i=0:length(t)-1,

y(i+1) = w * total_sinyal(:,i+1);

e(i+1) = sinyal_terima(i+1)-y(i+1);

w = w + mu *e(i+1)*(total_sinyal(:,i+1))';

end;

%PLOT

close all;

figure;

plot(abs(y),'r');

hold;

plot(abs(sinyal_terima),'--b');

ylabel('desired signal');

xlabel('iterasi');

legend('magnitude(d)','magnitude (y)')

hold off;