########### GR-DRM, A SOFTWARE DRM/DRM+ TRANSMITTER FOR GNU RADIO ##############

CONTENTS: 	1: Installation
			2: Usage
			3: Features
			4: (Current) Constraints
			5: Known Bugs


1 INSTALLATION

Dependencies:		GNU Radio, UHD, FAAC, FAAD2

For installation instructions for GNU Radio and UHD please visit 
http://www.gnuradio.org (there is a build script making things really easy!).

FAAC:	

wget http://downloads.sourceforge.net/faac/faac-1.28.tar.gz
tar zxf faac-1.28.tar.gz
cd faac-1.28
. bootstrap
./configure --with-pic --disable-shared --without-mp4v2 --enable-drm
make
sudo cp include/faaccfg.h  include/faac.h /usr/include
sudo cp libfaac/.libs/libfaac.a /usr/local/lib
cd ..
		
FAAD2:	

wget http://downloads.sourceforge.net/faac/faad2-2.7.tar.gz
tar zxf faad2-2.7.tar.gz
cd faad2-2.7
. bootstrap
./configure --disable-shared --without-xmms --without-bmp --with-drm --without-mpeg4ip --with-pic
make
sudo cp include/faad.h include/neaacdec.h /usr/include
sudo cp libfaad/.libs/libfaad.a /usr/local/lib
cd ..
		
gr-drm:	

git clone git://github.com/fewu/gnuradio_drm.git
cd gnuradio_drm/gr-drm
git checkout stable
mkdir build
cd build
cmake ../
make
sudo make install
sudo ldconfig
ctest # (optional) at the moment this has to be done after make install as there is a problem with proper importing of drm_swig
../../misc/set_grc_path.sh # this replaces the hardcoded home folder in the hier block XML defs with yours
cp ../../hier_blocks/* ~/.grc_gnuradio/ # or wherever you store your hier blocks (GRC has to be run once before executing this command)
		
		
2 USAGE

There are various, fully configured flow graphs under gnuradio_drm/flow_graphs 
that can be used pretty much as-is. The DRM+ flow graph does not crash but is
completely untested.

Of course you have to set the path to your USRP (or leave it blank for 
autodetection) and a source wav-file (either 12 or 24 kHz). There are also 
several other parameters you can change (see section Features). It is also 
possible to record a wav-file that can be decoded with DREAM.

As wav files usually aren't sampled with 12 or 24 kHz, I use sox for convenient
resampling.
Syntax: 'sox <mysong.wav> -r <new_sample_rate> <mysongresampled.wav> resample'


3 FEATURES

This project features a DRM/DRM+ software transmitter fully integrated into GNU Radio
Companion.

You are also free to play around with several robustness modes (RM) and spectrum 
occupancies (SO, signal bandwidth) ranging from 4.5 to 20 kHz. The corresponding
bit rates vary from below 5 kbps to about 55 kbps. Among other parameters, the
station label and a text message can also be set by simply adapting the 
correspondent blocks.


4 (CURRENT) CONSTRAINTS

As this project is still under development, there are some features of the DRM
standard that are not (yet) available. The most important are:
- Unequal Error Protection (UEP)
- Hierarchical mapping (HMsym and HMmix)
- multiple audio/data streams (currently only one audio stream in AAC Mono (no 
  SBR) is possible)
- Reconfiguration


5 KNOWN BUGS

- text message corrupted for SO 5 / RM A (and possibly other modes) 

################################################################################
If you find any bugs or have great ideas you think the project could benefit 
from, just write me: uncnr[at]student.kit.edu

last updated on: 2012/08/24