Binary phase shift keying

Matlab program for Binary phase shift keying.

Matlab code

clc;clear all;close all;

A1=1;   %Amplitude of Carrier Wave

fc=input('Enter the frequency of carrier wave(fc)= ');

n=input('Enter the no of bit= ');

r=input('Enter the Bite Rate (In bits/sec)= ');

tpb=1/r; %Time duration for per bit

x=rand(1,n); x

   for i=1:length(x)

       if x(i)>=0.5

           B(i)=1;

       else

           B(i)=0;

       end;

   end;

B  

t1=0;         %Temporary variable for time

st=[];         %Variable for store time

Sbs=[];      %Variable for store Bit stream

Sbpsk=[];  %Variable for store bpsk signal

for i=1:length(B)

    if B(i)==0                                    % When bit is 0 --

        t=t1:0.001:t1+tpb;                   % for time duration tpb behaviour of--

        Bs=zeros(1,length(t));             % Bit stream and--

        bpsk=A1*sin(2*pi*fc*t+pi);  % bpsk signal.

    else

        t=t1:0.001:t1+tpb;

        Bs=ones(1,length(t));

        bpsk=A1*sin(2*pi*fc*t);

    end;

    st=[st t];                       %storing tpb duration of time

    Sbs=[Sbs Bs];             %storing Bit stream in tpb duration

    Sbpsk=[Sbpsk bpsk];  %storing bpsk signal in tpb duration

    t1=t1+tpb;                   %initial value of next tpb duration for iteration

end;

Sc=A1*sin(2*pi*fc*st);  %Carrier Wave

subplot(4,1,1);

plot(st,Sbs);

axis([0 tpb*n -2 2])

xlabel('Time');ylabel('Amplitude');title('Bit stream');

subplot(4,1,2);

plot(st,Sc);

xlabel('Time');ylabel('Amplitude');title('Carrier wave');

subplot(4,1,3);

plot(st,Sbpsk);

xlabel('Time');ylabel('Amplitude');title('BPSK Signal');

subplot(4,1,4);

plot(st,Sbs);

axis([0 tpb*n -2 2])

hold on;

plot(st,Sbpsk,'-.r');

xlabel('Time');ylabel('Amplitude');title('Bit stream and BPSK Signal');

h=legend('Bit stream','BPSK Signal');

Command window

Enter the frequency of carrier wave (fc) = 1

Enter the no of bit = 15

Enter the Bite Rate (In bits/sec) = 1

x =

  Columns 1 through 9

    0.8147    0.9058    0.1270    0.9134    0.6324    0.0975    0.2785    0.5469    0.9575

  Columns 10 through 15

    0.9649    0.1576    0.9706    0.9572    0.4854    0.8003

B =

     1     1     0     1     1     0     0     1     1     1     0     1     1     0     1

Figure window