Re: [Discuss-gnuradio] OFDM Preamble

2017-08-25 Thread Edwin Li 
Hi Adhitha,

I haven't used the "OFDM Insert Preamble" module before. But in my
understanding, in tx_ofdm.grc, "OFDM Carrier Allocator" does the job of
"OFDM insert preamble". It uses "sync word" instead of "preamble". I think
they are the same thing. As for FFT length, keep it the same as your other
OFDM modules. Note that the length of a sync word must be the same as FFT
length.

Regards,
Edwin
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[Discuss-gnuradio] OFDM Preamble

2017-08-25 Thread Adhitha Dias 
Hi,

Could anyone please help me to set the input parameters in "OFDM Insert
Preamble" OOT in GNURadio? It has 2 parameters FFT Length, and Preamble.
Where should it be used in the tx_ofdm.grc example. Thank you for the help
in advance.

Regards,
Adhitha Dias
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[Discuss-gnuradio] OFDM preamble

2011-07-01 Thread John Waugh 
Hi.
I wanted to know about the preambles that are inserted in the ofdm packet. I
know they are inserted for the synchronization and frequency offset
purposes.
But I want to know where in the OFDM packet they are inserted. I have
following questions.

1. How can I vary the length of preambles? Can I do that ?

2. On which parameters length of preamble depends?

3. What is the length of preamble sequence if I am using fft-length=512,
occupied carriers=200 cp-length=128, size of ofdm packet=400 bytes,
modulation='bpsk'.

4. Where are they inserted in the OFDM packet? I mean before Payload?

   
  preamble| payload|
   
5.  Both the preambles are inserted at the start ?

6. Which modulation is used for preambles?

Need your help

Regards
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