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[Discuss-gnuradio] State of HDTV 2

From: Charles Swiger
Subject: [Discuss-gnuradio] State of HDTV 2
Date: Wed, 05 Apr 2006 17:27:51 -0400

On Wed, 2006-04-05 at 10:16 -0700, Eric Blossom wrote:

> I moved it all to a new module, gr-atsc in CVS.
> It's already autoconfiscated and ready to go.  There's a file,
> README.signal_flow in the top level directory that tells how the old
> code was connected together.  There are loopback tests for the first
> two blocks in each direction in the python directory.
> The normal:
>   ./bootstrap
>   ./configure
>   make && make check && make install

Ok, found it - If I understand correctly, it looks like the next block
to finsh is the convolutional interleaver, and it's reverse the 
convolutional de-interleaver.

Existing 2.0 layers:

Src (mpeg transport)                Dst
       v                               ^
Randomizer                          Derandomizer
       v                               ^
Reed-Soloman Encoder      ----->    RS Decoder

Yet to be done:

       v                                     ^
Convolutional Interleaver     ->      De-Interleaver
       v                                     ^
Trellis Encoder               ->      Viterbi Decoder
       v                                     ^
Field Sync Multiplexor        ->      Field Sync Demux
       v                                     ^
Symbol Mapper                         Equalizer
       v                                     ^
Weaver Modulator Head                 Field Sync Checker
       v                                     ^
FIR Filter (lp root raised cosine)    Bit Timing Loop3
       v                                     ^
Weaver Modulator Tail                 Remove DC 
       |                              FIR Filter, Image Remove
       |                                     ^
       |                              FPLL Carrier Tracking PLL 
       |                                 and down converter
       |        IF                           ^
       +----------------->            FIR Filter (lp root raised

Actually the FIR filters already exist, as does the carrier tracking
PLL and mixer. Since we start with a complex source already (usrp
in place of the mc4020 'short' data source) image removal won't be
necessary (I guess). So really all we need is the logic from 6 blocks
repackaged for a receiver, and 6 for a transmitter to do stage-by-stage
testing.  IIUC.


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