untitled2.m

uwb的信号产生以及几种调制方法

t=(0:0.1:1);
k=[5,6,2.8];

Tm=0.5e-9;
b=[0.7,0.001,0.15];

r(t)={k+4*k*exp(-b*t)/[(k*x)/2+(1-k)/2*k-(b*t*x)/4]};
[r1]=r(k1,Tm,b1);
[r2]=r(k2,Tm,b2);
[r3]=r(k3,Tm,b3);
time=linspace(-Tm/2,Tm/2,length(b1));

dt = 1 / fc;            % reference sampling period
OVER = floor(Tm/dt);    % number of samples representing
                        %  the pulse

e = mod(OVER,2);
kbk = floor(OVER/2);
tmp = linspace(dt,Tm/2,kbk);
s = (1-4.*pi.*((tmp./tau).^2)).* ...
     exp(-2.*pi.*((tmp./tau).^2));

if e                % OVER is odd
    for k=1:length(s)
        y(kbk+1)=1;
        y(kbk+1+k)=s(k);
        y(kbk+1-k)=s(k);
    end
else                % OVER is even
    for k=1:length(s)
        y(kbk+k)=s(k);
        y(kbk+1-k)=s(k);
    end
end

E = sum((y.^2).*dt);     % pulse energy
w0 = y ./ (E^0.5); 
  fc=5e10;
Tm=0.5e-9;
tau1=0.2333e-9;
[a1]=s(fc,Tm,tau1);

time=linspace(-Tm/2,Tm/2,length(a1));

yy=conv(s,r);
p=plot(time,b1,k1,time,b2,k2,time,b3,k3);
grid on 
legend('刚','波','是');
xlabel('时间(ns)');
ylabel('幅度');