Hi all,
I’m doing a spacecraft link budget analysis in MATLAB. I have a function that calculates the link margin, which I call in a main script. As I wish to limit the margin to a certain range I use a While Loop that alters the transmission power (P_t) until the condition is satisfied.
P_t=5;
flag_para=0;
flag_helix=0;
flag_horn=0;
flag_array=1;
S=S_epsilon*1000;
R_b=20e+6;
BER=8e-6;
dl=3;
A=0.1; % phase array
D_t=0; % Parabolic
eta=0.7;
f_t=8e+9;
lamda=3e+8/f_t; % Operating Wavelength in metres
L_com=0; % horn
margin=-inf;
j=1;
while margin<6 && margin>12
[margin,M_com,P_com,L_ant]=comm_payload(flag_para,flag_helix,flag_horn,flag_array…
,P_t,eta,lamda,D_t,f_t,L_com,A,S,dl,R_b,BER);
if margin<6
P_t=P_t*1.1;
j=j+1;
elseif margin>12
P_t=P_t*0.9;
j=j+1;
end
end
This doesn’t seem to be working. The code runs but J stays at 1 and the margin also remains at -inf. Any ideas what is wrong? The function 100% works, tested it many times without the while loop.
CheersHi all,
I’m doing a spacecraft link budget analysis in MATLAB. I have a function that calculates the link margin, which I call in a main script. As I wish to limit the margin to a certain range I use a While Loop that alters the transmission power (P_t) until the condition is satisfied.
P_t=5;
flag_para=0;
flag_helix=0;
flag_horn=0;
flag_array=1;
S=S_epsilon*1000;
R_b=20e+6;
BER=8e-6;
dl=3;
A=0.1; % phase array
D_t=0; % Parabolic
eta=0.7;
f_t=8e+9;
lamda=3e+8/f_t; % Operating Wavelength in metres
L_com=0; % horn
margin=-inf;
j=1;
while margin<6 && margin>12
[margin,M_com,P_com,L_ant]=comm_payload(flag_para,flag_helix,flag_horn,flag_array…
,P_t,eta,lamda,D_t,f_t,L_com,A,S,dl,R_b,BER);
if margin<6
P_t=P_t*1.1;
j=j+1;
elseif margin>12
P_t=P_t*0.9;
j=j+1;
end
end
This doesn’t seem to be working. The code runs but J stays at 1 and the margin also remains at -inf. Any ideas what is wrong? The function 100% works, tested it many times without the while loop.
Cheers Hi all,
I’m doing a spacecraft link budget analysis in MATLAB. I have a function that calculates the link margin, which I call in a main script. As I wish to limit the margin to a certain range I use a While Loop that alters the transmission power (P_t) until the condition is satisfied.
P_t=5;
flag_para=0;
flag_helix=0;
flag_horn=0;
flag_array=1;
S=S_epsilon*1000;
R_b=20e+6;
BER=8e-6;
dl=3;
A=0.1; % phase array
D_t=0; % Parabolic
eta=0.7;
f_t=8e+9;
lamda=3e+8/f_t; % Operating Wavelength in metres
L_com=0; % horn
margin=-inf;
j=1;
while margin<6 && margin>12
[margin,M_com,P_com,L_ant]=comm_payload(flag_para,flag_helix,flag_horn,flag_array…
,P_t,eta,lamda,D_t,f_t,L_com,A,S,dl,R_b,BER);
if margin<6
P_t=P_t*1.1;
j=j+1;
elseif margin>12
P_t=P_t*0.9;
j=j+1;
end
end
This doesn’t seem to be working. The code runs but J stays at 1 and the margin also remains at -inf. Any ideas what is wrong? The function 100% works, tested it many times without the while loop.
Cheers while loop MATLAB Answers — New Questions

​