I just pulled a new copy and make test still fails for me with various
missing .dat files.
Can anyone else confirm that make test is working ok for them with the
latest version?
On Thu, Dec 19, 2013 at 3:07 PM, Johannes D. [email protected] wrote:
Currently synchronization doesn’t support fractional CPs. Besides this,
reducing the sample rate helps a lot to make it run faster. Only thing to
keep in mind though, having a different number of blocks than used by the
base station will only allow you to decode PBCH. But for a start. That’s not
much of a problem.
The fractional CP is a pain to deal with. Performing acquisition at
1.92 Msps, though, is quite reasonable and is appropriate for 1.4 MHz
LTE channels anyways.
UE side LTE decoding is inherently a multirate process. PBCH decoding
should ideally be performed at the reduced sample rate because any
data outside of the inner 6 RBs provides no useful information to the
search and decoding process. The same concept extends to any channel
configurations below the full LTE 30.72 Msps rate. But, since the
channel bandwidth is unknown until PCBH acquisition, the receiver
should, ideally, support all rates and dynamically switch between them
as needed.
Practically speaking, the issue with real-time operation on USRP type
devices is that we can’t switch device sample rates without breaking
symbol timing or slot alignment. That means running a fixed device
rate and multiple resampling chains to cover the desired channel
bandwidths.
But yes, sticking with one sample rate avoids all of the above, and is
a much simpler way to start. Perhaps multirate handling is something
to consider for future development. If there were only more hours in a
day…
it would be really helpful if you posted the error message. If it is
more than a few lines, pastebin’ing would be good. Also can you tell
on which branch you’re on? I’m worried about missing ‘.dat’ because
they shouldn’t be there. I thought I removed all references to them a
while ago.
Mike
note that a few tests fail when I run make test, is that to be
<mailto:[email protected]mailto:[email protected]>> wrote:
messages in this thread for details).
Hi everybody,
into this.
Decode PBCH and
flowgraph. If you opened a flowgraph with missing blocks, as
On Wed, Dec 18, 2013 at 3:49 AM, Ralph A. Schmid, dk5ras
has missing blocks, at least LTE estimator
Just wanted to put this all together in my lunch
<mailto:[email protected] mailto:[email protected]
Hello GNU Radio enthusiasts,
Now, all current blocks are moved to the GNU Radio
installation process. mailto:[email protected]
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.12 (GNU/Linux)
Comment: Using GnuPG with Thunderbird - http://www.enigmail.net/
Do you have the possibility to upload the file to my server? It is on a
VDSL50 line (50Mbps in, 10 Mbps out), so upload from the university
(DFN)
network should be fast enough. Then I could post a link for direct
download
(well, only 10 Mbps) and provide the file via bittorrent…
Ralph.
On 12/19/2013 03:24 AM, Ralph A. Schmid, dk5ras wrote:
-----Original Message-----
Happy hacking
Johannes
On 18.12.2013 23:54, Mike C. wrote:
Hi Johannes,
With regard to my earlier message regarding the crash I’m seeing, I
note that a few tests fail when I run make test, is that to be
expected?
Also do you think it would be possible to publish the reference
waveform that you are using ?
That way I could check to see if the crash occurs with your known
‘good’
I had the same problem at first myself, there is no need to
On 19 December 2013 18:27, Johannes D.
<[email protected] mailto:[email protected]> wrote:
Hi everybody,
I added screenshots for all the hierarchical flowgraphs and
the
top
flowgraph to the docs directory. I hope this helps to build
the
block. These
least this
> Hi,
>
> Just wanted to put this all together in my lunch break,
but seems
> too big for such a short break anyway :)
>
> Ralph.
>
>
> > -----Original Message-----
> > From:
regarding the different parameters. ‘tx_diversity’ should always be left
as
it is. In case of a 1x1 MIMO configuration it will just have no effect.
This parameter reflects the LTE standard with its two options
‘tx_diversity’ and ‘spatial_multiplexing’. The latter isn’t used for
control channels.
In order to specify a certain bandwidth, use the parameter ‘N_rb_dl’,
which
specifies the number of resource blocks used. This will also set the
bandwidth as this is the unit given by the system to determine the
bandwidth. e.g. have a look at the paper which is included in the
project
there is a table which shows the dependencies.
25 RBs --> 25*12 = 300 subcarrier --> 15kHz * 300 + spacing = 5MHz.
The FFT length can be chosen freely as long as it provides sufficient
bins
to match the current number of subcarriers. It will be used to determine
the input sample rate. I suggest you stick with power of 2 values. Those
are the only ones I tested and the numbers the system is designed for.
One
more thing, a FFT length shorter than 256 results in fractional CP
lengths,
which should be avoided. LTE’s CP use is already quite tricky and the
introduction of fractional CP lengths will not ease the situation.
PBCH decoding is handled for one and two antenna configurations, so you
don’t have to worry about configuring the flowgraph there.
PCFICH decoding will receive a message on runtime which sets the decoded
antenna configuration.
I’m back at work after the new year break and have had a chance to try
this
again, and I think I have it working !!
The problem was with my test waveform, I’ve captured a new test waveform
and I can now sync to the DL signal and decode the MIB.
thank you very much for updating your gr-lte package. I could compiled
all .grc files succesfully. Now I would like to test your receiver with
a LTE signal saved to a file with the following settings.( 5 MHz, RB 25,
fft 512, occupied carriers 300, no tx diversity). So I have started to
change the parameters in your grc files.
RB 25 instead 50
fftlen 512 instead 2048(is it right?)
occupied carriers 300 instead 600.
So I have realized the files decode_pcfich_37.grc and decode_pbch_37
.grc are designed for tx_diversity with two antennas. How can I change
it? Removing the blocks for the second antenna perhaps?
Thank you very much.
A. Baier
I m trying to generate the LTE_flowgraph_top_level.grc but the Decode
PBCH block is missing due to an error in decode_pbch_37.grc .
The error is the following:
Correlating the grc with the images at docs folder, I can see that the
input is a vector with length 240 and the input of PBCH Descrambler is a
vector with length 480.
Also some tests failed due to this error:
import lte_swig as lte
ImportError: No module named lte_swig
This sounds like an interface mismatch between blocks. To answer your
question accurately it would be very helpful to know which version of
GNU Radio and which gr-lte version you use. Branch and day of last
commit should be sufficient. Also tell us about your general setup.
Which OS are you using?
happy hacking
Johannes
On 13.02.2014 18:40, Passas Virgilios wrote:
size “1920” does not match sink IO size "7680.
to try this again, and I think I have it working !! The problem
Sorry for not mentioned the versions.
GNU Radio 3.7.2.1
gr-lte branch-master, latest
commit 3ded865f40cc43224eca66a6692fa90655a25b62
Ubuntu 13.04 64-bit
Virgilios
Στις 8:24 μ.μ. Πέμπτη, 13 Φεβρουαρίου 2014, ο/η Johannes D. [email protected] έγραψε:
-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1
Hi Virgilios,
This sounds like an interface mismatch between blocks. To answer your
question accurately it would be very helpful to know which version of
GNU Radio and which gr-lte version you use. Branch and day of last
commit should be sufficient. Also tell us about your general setup.
Which OS are you using?
happy hacking
Johannes
On 13.02.2014 18:40, Passas Virgilios wrote:
size “1920” does not match sink IO size "7680”.
to try this again, and I think I have it working !! The problem
This sounds very close to my setup. I checked everything on my machine
and couldn’t find a reason for that to happen.
Your error says that the QPSK soft demod block has 480 float items as
output which corresponds to 1920 bytes. This is exactly as it is
supposed to be. Thus something went wrong with the descrambler. I
suggest you check this hier block for problems. The problem is
somewhere in there. Maybe delete the generated files and regenerate
them. Also make sure that all the values fit.
One other thing about vector lengths. The QPSK soft demod block’s
vector length corresponds to its input. So for every complex input
sample 2 float output samples are generated. Thus the vector length of
480 for the descrambler input.
I hope this brings you closer to a solution.
happy hacking
Johannes
On 13.02.2014 19:53, virgil passas wrote:
happy hacking Johannes
lte_pbch_descrambler_vfvf_0 - PBCH
import lte_swig as lte ImportError: No module named lte_swig
Hi Johannes,
will just have no effect. This parameter reflects the LTE
match the current number of subcarriers. It will be used to
compiled all .grc files succesfully. Now I would like to test
i have installed gr-lte in gnuradio 3.7.2 .All hier blocks are generated
and flow graph is complete upto unpack MIB.Is that it?.But when i run
this i get following error
Using Volk machine: sse4_2_32
pbch_pre_decoder_vcvc_1 set N_ant to 2
pbch_pre_decoder_vcvc_1 set decoding style to “tx_diversity”
pbch_pre_decoder_vcvc_0 set N_ant to 1
pbch_pre_decoder_vcvc_0 set decoding style to “tx_diversity”
pbch_layer_demapper_vcvc_1 set N_ant to 2
pbch_layer_demapper_vcvc_1 set decoding style to “tx_diversity”
pbch_layer_demapper_vcvc_0 set N_ant to 1
pbch_layer_demapper_vcvc_0 set decoding style to “tx_diversity”
RS GENERATOR cell_id pilots 1
RS GENERATOR cell_id pilots 0
Traceback (most recent call last):
File “/home/cdot/top_block.py”, line 218, in
tb = top_block(N_rb_dl_0=options.N_rb_dl_0)
File “/home/cdot/top_block.py”, line 92, in init
self.decode_bch_hier_gr37_0 = decode_bch_hier_gr37()
File “/root/.grc_gnuradio/decode_bch_hier_gr37.py”, line 46, in init
self.bch_lte_bch_viterbi_vfvb_0 = lte.bch_viterbi_vfvb()
File “/usr/local/lib/python2.7/dist-packages/lte/bch_viterbi_vfvb.py”,
line 42, in init
self.vtss = blocks.vector_to_streams(1* gr.sizeof_float, 120,
“bch_viterbi_vector_to_streams_0”)
File
“/usr/local/lib/python2.7/dist-packages/gnuradio/blocks/blocks_swig1.py”,
line 369, in make
return _blocks_swig1.vector_to_streams_make(*args, **kwargs)
TypeError: vector_to_streams_make() takes at most 2 arguments (3 given)
Hi. I downloaded the latest version of gnuradio(3.7.8.1) and complied
the code for the LTE Receiver framework. However I am having problems
with the results. I have attached the screenshot of the final output of
the LTE top level flowgraph. I am getting this “gr::log :INFO: MIB0 -
MIB decoding_rate = -nan” as an output. Is there a problem with my
input signal I generated it from Matlab LTE toolbox.Thanks
I got the LTE flowgraph up Unpack MIB ,but i am not able to see output
since i dont have .dat file.Can someone give link for sample .dat file?
At the end of the unpack MIB what is the expected output?
