function msg = bpsk(x,fc)



onebit=101; %number of samples per bit

n=(length(x))/onebit; %number of bits transmitted

b=onebit;

c=1;

msg=[];



for m=1:n; %iteration from 1 to number of bits

    y=x(c:b); % take the needed signal for one bit

    f=cos(2*pi*fc*(0:100));%reference signal for Quadrature

    g=cos(2*pi*fc*(0:100)+pi);%reference signal for Inphase

    a=y.*f; % (received signal) . (reference signal for Quadrature)

    d=y.*g; % (received signal) . (reference signal for Inphase)

    t= sum(a)-sum(d); %constellation

    if t>0;

        msg = [msg 1]; %accumulate the value of output into msg

    else

        msg = [msg -1]; %accumulate the value of output into msg

    end

    b=b+onebit; %update the value of b for the next input

    c=c+onebit; %update the value of c for the next input

end