msmart.m

This file contians three programs which used for Smart antenna simulation,including DOA estimation b

%------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------%
%                               This Program is Designed To Simulate The Smart Antenna System  On A BTS Receiver ( Uplink )                                %
%                                                             General Constraints For Using This Software                                                                                                     %
%Antenna Array Of Four Elements Operating On 2 GHz With A Separation Distance 0.075 Meters                                                                %
%Narrowband ( Uncorrelated Or Partially Correlated ) Signals Are Assumed                                                                                                         %
%An Authentication Code Of 10 Bits Is Sent First                                                                                                                                                               %
%Two Users Are Served Only In The Presence Of Additive White Gaussian Noise Only                                                                                      % 
%Operation Is Subdivided Into Three Stages : Angle Of Arrival Estimation ( MUSIC ) , Adaptive Beamforming , Signal Regeneration  %
%--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------%
%Input Received Signals Arrival
P = input ('The Channel Signal To Noise Ratio : ') ;
for I = 1 : 2
    A ( I ) = input ('The Signal Arrival Phase Angle : ') ;
    A ( I ) = A ( I ) * pi / 180 ;
end
H = randint ( 2 , 10 ) ;
%Estimation of The Covariance Matrix
S = zeros ( 4 , 2 ) ;
R = zeros ( 4 , 4 ) ;
ZZ = zeros ( 4 , 10 ) ;
for K = 1 : 10
    for J = 1 : 2
        for I = 1 : 4
            S ( I , J ) = exp ( i*( pi  * ( I - 1 ) * cos ( A ( J ) ) ) )  ;  
        end
    end
    S = awgn ( S * H ( : , K ) , P ) ;
    ZZ ( : , K ) = S ;
    R = R + S * S' ;
end
R = R / 10 ;
[ V , E ] = eig ( R , 'nobalance' ) ;
%MUSIC Algorithm Estimation
for J = 1 : 4
    for I = 1 : 2 
        VV ( J , I ) = V ( J , I ) ;
    end
end
I = 1 ;
F = zeros ( 1 , 629 ) ;
for T = 0 : 0.005 : pi 
    K = 0 : 3 ;
    B = exp ( j .* K * pi * cos ( T ) ) ;
    C = B.' ;
    F ( I ) = ( C' * C ) / ( C' * VV * VV' * C ) ;
    I = I + 1 ;
end
%Plot of The MUSIC Angular Pseudo Spectrum
T = 0 : 0.005 : pi ;
T = ( T * 180 ) / pi ;
FF = 10 * log10 ( abs ( F ) / max ( abs ( F ) ) ) ;
figure ( 1 ) , plot ( T , FF ) , xlabel ('The Phase Angle In Degrees') , ylabel ('The Angular Pseudo Spectrum') , title ('The Spatial MUSIC Spectrum') , grid on ;
%Estimation The Angle of Arrival For The Received Signals
for I = 1 : 629
    if FF ( I ) == 0 FF ( I ) = 1000 ;
    end
end
FF = imregionalmax ( FF ) .* FF ;
for I = 1 : 629
    if FF ( I ) == 0 FF ( I ) = -1000 ;
    end
end
for I = 1 : 2
    Y = max ( FF ) ;
    for J = 1 : 629
      if Y == FF ( J )  ;
         G ( I ) = ( T ( J ) * pi ) / 180 ;
         FF ( J ) = -1000 ;
      end
    end
end
%Estimation The Weight Vector of A Null Steering Beamformer
for I = 1 : 2
   for J = 1 : 4
       SS ( I , J ) = exp ( i*( pi * ( J-1 ) * cos ( G ( I ) ))) ;
  end
end
B = eye ( 2 ) ;
for J = 3 : 4
    Z = B ( J-2  , : ) ;
    W = SS \ Z' ;
    MM = 0 ;
    %Plot of The Output Radiation Pattern And The Output Valid Digital Data of The Null Steering Beamformer
    TT = 0 : 0.005 : pi ;
    for I = 1 : 4
       HH = exp ( i*( pi * ( I-1 )*cos ( TT ))) ;
       MM = MM + ( HH * W(I) ) ;
    end
    TT = ( TT * 180 ) / pi ;
    MM = 20 * log10 ( abs ( MM )/ max ( abs ( MM ) ) ) ;
    for K = 1 : 10
       OO ( K ) = W.' * ZZ ( : , K ) ;
    end
    OO = abs ( OO / max ( OO )) ;
    OO ( 11 ) = 0 ;
    U = J - 1  ;
    UU = J + 1 ;
    UUU = J + 3 ;
    figure ( U ) , plot ( TT , MM ) , xlabel ('Phase Angle In Degrees') , ylabel ('Electric Field In dB') , title ( 'A Choice Radiation Pattern Of A Spatial Beamformer') ,  axis ( [ 0 180 -10 0 ] ) , grid on ;     
    figure ( UU ) , stairs ( OO , 'linewidth' , 2 ) , title ('A Choice Output Digital Data') ,  xlabel ('The Bit Transition Period') , ylabel  ('The Output Digital Signal') , grid on ;
    %Comparator Operation
    for I = 1 : 10
        if OO ( I ) > 0.5 OO ( I ) = 1 ;
        else OO ( I ) = 0 ;
        end
    end
    figure ( UUU ) , stairs ( OO , 'linewidth' , 2 ) , title ('The Output Valid Digital Data') ,  xlabel ('The Bit Transition Period') , ylabel  ('The Output Digital Signal') , grid on ;
end