i am new at CVX. this problem is convex and i stimulate it ，the result shows convex programing error. plz somebody help me that where is my problem(or give me some advice). thanks sincerely！

```
clc
clear all
H = 120;Ws = [0,0];Wn = [300,300];Wf = [500,500];Wr = [400,400];
Pt = 4; B0 = 10^(-3);a = 2;N = 10^(-10);
ksr = 0.01;krn = 0.01;krf = 0.01;
dsr = sqrt(H^2+norm(Wr-Ws)^2);
drn = sqrt(H^2+norm(Wr-Wn)^2);
drf = sqrt(H^2+norm(Wr-Wf)^2);
hsr = B0/dsr^(-a);
hrn = B0/drn^(-a);
hrf = B0/drf^(-a);
b1 = 1+ksr^2; b2 = 1+krf^2; b3 = 1+krn^2;
d1 = (ksr^2+krf^2+ksr^2*krf^2);
d2 = (ksr^2+krn^2+ksr^2*krn^2);
cvx_begin
variable Ps
variable Pr
variable an
variable af
variable haha
maximize haha;
subject to
0.5*log2(1+an*Ps/N*hsr^2*Pr/N*hrn^2/(d2*Ps/N*hsr^2 ...
*Pr/N*hrn^2+b1*Ps/N*hsr^2+b3*Pr/N*hrn^2+1)) + ...
0.5*log2(1+af*Ps/N*hsr^2*Pr/N*hrf^2/((an+d1)*Ps/N*hsr^2 ...%R1 = log2(1+SINR)
*Pr/N*hrf^2+b1*Ps/N*hsr^2+b2*Pr/N*hrf^2+1)) >= haha;%sum(R1 + R2) >= haha
0 < an;
an < 1;
0< af;
af < 1;
an + af == 1;
Ps + Pr == Pt;
Ps >= 0;
Pr >= 0;
Rn >= 1;
Rf >= 1;%objective function and constraints are convex
```

cvx_end