upt0zer0
Newbie level 1
Hi
First of all sry for bad english.
I hope I am right here. So I have made a simulink model of an ofdm system.
Modulator, FFT, etc no problem, ... the time synchronization works, too. But the frequency synchronization don't.
Every step I produce one ofdm symbol. So a vector has for examples 64 elements. Next there is the FFT,... next step there is a second ofdm symbol etc etc... i hope you understand it.
So now i want to make frequency synchronization / estimation. For this, I send to preamble blocks (A|A) and than my Simulink level-2 S-function multiply first element of first block with first element of second block, than second element of first block with second element of second block etc....
To get the phase difference, I used the command "angle".
And now my problem starts, i want to calculate the frequency out of the phase difference, for that, I have this formula:
f = (phase_difference) / 2*pi*(delta_T)
So what is delta_T??? It should be the time between the two symbols I multiply. But I don't know this time.... where can I get it from?
Thx for any help
Another question:
For testing the frequency synchronization, i need a frequency offset. I tried it with the block "Phase/Frequency Offset" but that didn't work.
First of all sry for bad english.
I hope I am right here. So I have made a simulink model of an ofdm system.
Modulator, FFT, etc no problem, ... the time synchronization works, too. But the frequency synchronization don't.
Every step I produce one ofdm symbol. So a vector has for examples 64 elements. Next there is the FFT,... next step there is a second ofdm symbol etc etc... i hope you understand it.
So now i want to make frequency synchronization / estimation. For this, I send to preamble blocks (A|A) and than my Simulink level-2 S-function multiply first element of first block with first element of second block, than second element of first block with second element of second block etc....
To get the phase difference, I used the command "angle".
And now my problem starts, i want to calculate the frequency out of the phase difference, for that, I have this formula:
f = (phase_difference) / 2*pi*(delta_T)
So what is delta_T??? It should be the time between the two symbols I multiply. But I don't know this time.... where can I get it from?
Thx for any help
Another question:
For testing the frequency synchronization, i need a frequency offset. I tried it with the block "Phase/Frequency Offset" but that didn't work.
