Upconverting of OFDM and Dota.

Dear sirs;
I have a question about OFDM signal spectrum. I will be so glad if you answer to that. If we have 200 carriers with 100Hz carrier spacing, after OFDM, what's the band width of signal on the RF=1300kHz. is it 20kHz or 40kHz? and why?

WITH THE BEST REGARDS
Maryam Sedaghat

Miss Sedaghat,

Up converting a signal to RF or carrier frequency doesn't change the bandwith of your signal: it is just a frequency translation. If we look at your system in baseband, we see that you have 200 subcarriers witha frequency spacing of 100 Hz so a BW = 20 KHz. This
answer is valid when you up convert by multiplication with exp(-j*2*pi*fc*t) where fc is your carrier frequency (1300 KHz).

On the other hand if you upconcvert real part and imaginary part of your baseband signal by multiplying thzm respectively by cos (2*pi*fc*t) and sin(2*pi*fc*t), you have 2*20 KHz= 40 KHz of BW.

Good luck,
Seyed Sajad Sadough

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I had been playing a lot of dota. To date, i joined a total of 3 tournament;
- irelax 2004?
- MMU GDC LGC 2005/06
- WCG College Preliminary 2006

and i am about to join another one. next week, organized by APIIT, the ICCG (InterCollege Cyber Games).

sigh, hope i can win this time.

Amount of competitions that we could've but didn't join;
- SMM N9, SMM Revenge.
- BananaNet.

i.need.to.finish.up.simulating.my.OFDM.codes