30 Dec
2013
30 Dec
'13
8:38 a.m.
Hi guys,
For the multiple dongles synchronization in signal level instead of
bits/packets level, I setup a working repo in github, and write a initial
demo framework. See below:
https://github.com/JiaoXianjun/multi-rtl-sdr-udp-relay.git
You may find information and instruction of demo quickly by reading the
README.
My initial purpose is performing in-fly calibration for multiple dongles
according to some pre-known signal (GSM, ADS-B?) to let them work together
coherently.
An ideal scheme may be that we should generate a very narrow band and very
week signal in (or just located at the edge of) target working band of
dongles, and perform the software in-fly calibration in background (or
driver level). This would be user friendly.
I know it is far from final state currently, and many things are not clear
yet (See TODO). But please join me if you also think this is a good idea.
Just check out the demo and run it to have a look.
Currently I just test the demo in Ubuntu-Linux.
BR
Jiao Xianjun
On Mon, Sep 2, 2013 at 8:23 PM, Sylvain AZARIAN
<sylvain.azarian(a)gmail.com>wrote;wrote:
Thanks.
sylvain
2013/9/2 Sdr Guru <sdrguru1(a)gmail.com>
The second way, use MLAT enabled dump1090
https://github.com/antirez/dump1090/pull/23
http://www.satsignal.eu/raspberry-pi/dump1090.html
On Sun, Aug 25, 2013 at 4:13 PM, Jiao Xianjun <putaoshu(a)gmail.com> wrote:
Hi,
I want to use multiple rtl-sdr dongles to do some multi-antenna
experiments.
Is it possible to read IQ samples from multiple rtl-sdr dongles in a
synchronized manner?
I already have a glance at dump1090 codes, which is a project using
rtl-sdr to decode aircraft broadcasting ADS-B messages in 1090MHz.
Seems that I should use rtlsdr_read_async() instead of
rtlsdr_read_sync(), because that if rtlsdr_read_sync() is used, I have to
call it multiple times sequentially. That looks not synchronized.
But rtlsdr_read_async() function only accept one rtl-sdr device as input
parameter, and it will be blocked after it is called. So seems that it also
can't be used for my purpose directly.
Also welcome any opinion on how to improve rtl-sdr lib/driver to
support this feature.
Thank you.
BR
Jiao Xianjun