# Voice Communication with USRP through OFDM

**URL:** <https://www.ruby-forum.com/t/voice-communication-with-usrp-through-ofdm/232434>\
**Category:** GNU Radio\
**Created:** [October 9, 2014, 10:33am UTC](https://www.ruby-forum.com/t/voice-communication-with-usrp-through-ofdm/232434 "2014-10-09T10:33:06Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![addis\_a](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/a/c4cdca/32.png) [@addis\_a](https://www.ruby-forum.com/u/addis_a)\
**Post date:** [October 9, 2014, 10:33am UTC](https://www.ruby-forum.com/t/voice-communication-with-usrp-through-ofdm/232434/1 "2014-10-09T10:33:06Z")

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Hello all,

I want to make a test communication system with USRP for narrow band HF  
range voice transmission and reception. Also I am interested in using  
OFDM  
scheme for that.

I need some guidance about what packages I should use for HF freq range  
and  
OFDM multiplexing…?

If someone could provide me any tutorial links for establishment of OFDM  
and HF communication link with USRP.

Thanks in advance.

–  
_Usman A._

_Electrical (Telecom) Engineering_  
_National University of Sciences and Technology (NUST)_

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<div class="post-metadata">

**Author:** ![ajaonchat](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/a/ed655f/32.png) [@ajaonchat](https://www.ruby-forum.com/u/ajaonchat)\
**Post date:** [October 9, 2014, 11:40am UTC](https://www.ruby-forum.com/t/voice-communication-with-usrp-through-ofdm/232434/2 "2014-10-09T11:40:16Z")

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Start with setting up the OFDM Transmitter and -Receiver blocks using  
random data. Make sure you’ve understood all the concepts along the way  
(tagged streams etc.).

Once that works, I recommend using the vocoder blocks to generate  
compressed digital voice data and pipe that into the OFDM codes.

Cheers,  
M