Adding guard interval in OFDM Matlab simulation

[Antonio_Magma]

ofdm guard interval in matlab

How do i add a guard interval (cyclic prefix) for an OFDM simulation in Matlab?

Coz in matlab the datas are represented in a matrix, however guard interval is in us (micro-seconds)..so how do i code it in matlab? and since the guard interval is a cyclic prefix, how do i copy the end and append it to the front of the OFDM symbol?

Thx in advance...

 

[bpu]

guard intervall matlab

data - [(A)*(symb_duration)x1] data vector in matlab

1) data = reshape(data,symb_duration,[]);

2) data = [data((end-guard_int+1):end,; data];

3) data = reshape(data,[],1);

that all. now we have the data with the guard interval

 

[Antonio_Magma]

guard interval in ofdm matlab

data - [(A)*(symb_duration)x1] data vector in matlab

Why is it '-' ? is it typo?

data - [(A)*(symb_duration)x1] data vector in matlab

Does symb_duration mean d lenght of my baseband data?

Which part does the code copies d end of the symbol? Since i need it to be a cyclic prefix

I'm sorry i'm a little weak with these..can u break it down n explain it 2 me? Appreciate it...

 

[bpu]

ofdm matlab simulation

Why is it '-' ? is it typo?

yes. data IS a [(A)*(symb_duration)x1] data vector in matlab.
symb_duration is a duration of the OFDM symbol. duration in any units, i.e. seconds, samples or etc.

Does symb_duration mean d lenght of my baseband data?

What is the d? data vector?

Which part does the code copies d end of the symbol? Since i need it to be a cyclic prefix

2) data = [data((end-guard_int+1):end) ; data];
guard_int is a guard interval duration in any units.

1) break the data vector to OFDM symbols
2) add the guard interval
3) combine OFDM symbols with the guard interval to the data vector

 

[Antonio_Magma]

matlab guard interval

bpu, i've got it...trial and error...thx man...