1 Aug
2016
1 Aug
'16
2:57 p.m.
Hi!
I've asked about it before but this seems to have been lost in
communication.
The question is basically how to enable multi-TRX support for
osmo-bts-trx using phy/instance infrastructure similar to other bts?
What I've tried so far is documented in
http://projects.osmocom.org/issues/1648 but it did not result in working
setup yet.
In short, I'd like to configure OpenBSC with 1 BTS with 2 TRX, each with
its own arfcn and set of channels. I'm running "osmo-bts-trx -t 2" and
correspondingly "osmo-trx -c 2" on usrp b210. Any ideas on what's
missing to make this actually work are greatly appreciated.
--
Max Suraev <msuraev(a)sysmocom.de> http://www.sysmocom.de/
=======================================================================
* sysmocom - systems for mobile communications GmbH
* Alt-Moabit 93
* 10559 Berlin, Germany
* Sitz / Registered office: Berlin, HRB 134158 B
* Geschaeftsfuehrer / Managing Director: Harald Welte
1 Aug
1 Aug
10:39 p.m.
Hi Max,
On Mon, Aug 1, 2016 at 7:57 AM, Max <msuraev(a)sysmocom.de> wrote:
I've asked about it before but this seems to have
been lost in
communication.
I do not recall this discussion. My apologies.
The question is basically how to enable multi-TRX
support for
osmo-bts-trx using phy/instance infrastructure similar to other bts?
I use the following configuration.
phy 0
instance 0
instance 1
osmotrx rx-gain 25
bts 0
band 900
ipa unit-id 1234 0
oml remote-ip 127.0.0.1
settsc
gsmtap-sapi ccch
gsmtap-sapi pdtch
trx 0
phy 0 instance 0
trx 1
phy 0 instance 1
$ osmo-bts-trx -c osmo-bts.cfg -t 2
In short, I'd like to configure OpenBSC with 1 BTS
with 2 TRX, each with
its own arfcn and set of channels. I'm running "osmo-bts-trx -t 2" and
correspondingly "osmo-trx -c 2" on usrp b210. Any ideas on what's
missing to make this actually work are greatly appreciated.
You can use "osmo-trx -c 2" or "osmo-trx -m -c 2" to use
dual-channels
of the B210 or multi-ARFCN on one channel respectively.
Note that there are ARFCN restrictions for both cases. Due to a shared
local oscillator for both B210 channels, ARFCN separation can be up
about 25 MHz.
With multi-TRX, ARFCN spacing is fixed at 800 kHz or 4 GSM channels.
So if TRX-0 is set to ARFCN 51, TRX-1 _must_ be set to 55. Up to three
ARFCN's is supported for multi-TRX.
-TT
10 Aug
10 Aug
1:42 p.m.
Hi.
Unfortunately I'm unable to make it work yet:
sudo chrt 20 ./Transceiver52M/osmo-trx -m -c 2 -g
linux; GNU C++ version 4.8.2; Boost_105400; UHD_003.008.004-0-unknown
opening configuration table from path :memory:
Config Settings
Log Level............... NOTICE
Device args.............
TRX Base Port........... 5700
TRX Address............. 127.0.0.1
Channels................ 2
Tx Samples-per-Symbol... 4
Rx Samples-per-Symbol... 4
EDGE support............ Disabled
Reference............... GPS
C0 Filler Table......... Disabled
Multi-Carrier........... Enabled
Diversity............... Disabled
Tuning offset........... 0
RSSI to dBm offset...... 0
Swap channels........... 0
-- Operating over USB 2.
-- Initialize CODEC control...
-- Initialize Radio control...
-- Performing register loopback test... pass
-- Performing register loopback test... pass
-- Performing CODEC loopback test... pass
-- Performing CODEC loopback test... pass
-- Asking for clock rate 32.000000 MHz
-- Actually got clock rate 32.000000 MHz
-- Performing timer loopback test... pass
-- Performing timer loopback test... pass
-- Asking for clock rate 3.200000 MHz
UHD Warning:
The requested master_clock_rate 3.200000 MHz exceeds bounds imposed
by UHD.
The master_clock_rate has been forced to 5.000000 MHz.
-- Actually got clock rate 5.000000 MHz
-- Performing timer loopback test... pass
-- Performing timer loopback test... pass
ALERT 3036182272 15:41:43.1 UHDDevice.cpp:546:set_master_clk: Failed to
set master clock rate
ALERT 3036182272 15:41:43.1 UHDDevice.cpp:546:set_master_clk: Failed to
set master clock rate
ALERT 3036182272 15:41:43.1 UHDDevice.cpp:547:set_master_clk: Requested
clock rate 3.2e+06
ALERT 3036182272 15:41:43.1 UHDDevice.cpp:547:set_master_clk: Requested
clock rate 3.2e+06
ALERT 3036182272 15:41:43.1 UHDDevice.cpp:548:set_master_clk: Actual
clock rate 5e+06
ALERT 3036182272 15:41:43.1 UHDDevice.cpp:548:set_master_clk: Actual
clock rate 5e+06
ALERT 3036182272 15:41:43.1 osmo-trx.cpp:530:main: Failed to create
radio device
ALERT 3036182272 15:41:43.1 osmo-trx.cpp:530:main: Failed to create
radio device
Shutting down transceiver...
On 08/02/2016 12:39 AM, Tom Tsou wrote:
Hi Max,
On Mon, Aug 1, 2016 at 7:57 AM, Max <msuraev(a)sysmocom.de> wrote:
--
Max Suraev <msuraev(a)sysmocom.de> http://www.sysmocom.de/
=======================================================================
* sysmocom - systems for mobile communications GmbH
* Alt-Moabit 93
* 10559 Berlin, Germany
* Sitz / Registered office: Berlin, HRB 134158 B
* Geschaeftsfuehrer / Managing Director: Harald Welte
I've asked about it before but this seems to
have been lost in
communication.
I do not recall this discussion. My apologies.
The question is basically how to enable multi-TRX
support for
osmo-bts-trx using phy/instance infrastructure similar to other bts?
I use the
following configuration.
phy 0
instance 0
instance 1
osmotrx rx-gain 25
bts 0
band 900
ipa unit-id 1234 0
oml remote-ip 127.0.0.1
settsc
gsmtap-sapi ccch
gsmtap-sapi pdtch
trx 0
phy 0 instance 0
trx 1
phy 0 instance 1
$ osmo-bts-trx -c osmo-bts.cfg -t 2
In short, I'd like to configure OpenBSC with
1 BTS with 2 TRX, each with
its own arfcn and set of channels. I'm running "osmo-bts-trx -t 2" and
correspondingly "osmo-trx -c 2" on usrp b210. Any ideas on what's
missing to make this actually work are greatly appreciated.
You can use
"osmo-trx -c 2" or "osmo-trx -m -c 2" to use dual-channels
of the B210 or multi-ARFCN on one channel respectively.
Note that there are ARFCN restrictions for both cases. Due to a shared
local oscillator for both B210 channels, ARFCN separation can be up
about 25 MHz.
With multi-TRX, ARFCN spacing is fixed at 800 kHz or 4 GSM channels.
So if TRX-0 is set to ARFCN 51, TRX-1 _must_ be set to 55. Up to three
ARFCN's is supported for multi-TRX.
-TT
5:26 p.m.
On Wed, Aug 10, 2016 at 6:42 AM, Max <msuraev(a)sysmocom.de> wrote:
sudo chrt 20 ./Transceiver52M/osmo-trx -m -c 2 -g
linux; GNU C++ version 4.8.2; Boost_105400; UHD_003.008.004-0-unknown
...
-- Asking for clock rate 3.200000 MHz
UHD Warning:
The requested master_clock_rate 3.200000 MHz exceeds bounds imposed
by UHD.
The master_clock_rate has been forced to 5.000000 MHz.
There is a UHD version requirement to clock the B200/B210 below 5 MHz,
which is preferred for timing reasons.
I am looking at the versioning. UHD master is obviously up to date.
-TT
6:08 p.m.
Hi Tom,
There is a UHD version requirement to clock the
B200/B210 below 5 MHz
Can you tell which version it is?
I am using 3.9.4
Regards,
Csaba
----- Eredeti üzenet -----
Feladó: "Tom Tsou" <tom(a)tsou.cc>
Címzett: "Max" <msuraev(a)sysmocom.de>
Másolatot kap: "OpenBSC Mailing List" <openbsc(a)lists.osmocom.org>
Elküldött üzenetek: Szerda, 2016. Augusztus 10. 19:26:26
Tárgy: Re: multiple phy with osmo-trx
On Wed, Aug 10, 2016 at 6:42 AM, Max <msuraev(a)sysmocom.de> wrote:
sudo chrt 20 ./Transceiver52M/osmo-trx -m -c 2 -g
linux; GNU C++ version 4.8.2; Boost_105400; UHD_003.008.004-0-unknown
...
-- Asking for clock rate 3.200000 MHz
UHD Warning:
The requested master_clock_rate 3.200000 MHz exceeds bounds imposed
by UHD.
The master_clock_rate has been forced to 5.000000 MHz.
There is a UHD version requirement to clock the B200/B210 below 5 MHz,
which is preferred for timing reasons.
I am looking at the versioning. UHD master is obviously up to date.
-TT
11 Aug
11 Aug
2:14 a.m.
On Wed, Aug 10, 2016 at 11:08 AM, Sipos Csaba
<sipos.csaba(a)kvk.uni-obuda.hu> wrote:
Unfortunately, the requirement turns out to be master. I'm testing a
workaround for prior UHD versions.
-TT
There is a UHD
version requirement to clock the B200/B210 below 5 MHz
Can you tell which version it is?
I am using 3.9.4
13 Oct
13 Oct
11 a.m.
What's the situation with UHD version support now?
I've tried running "./Transceiver52M/osmo-trx -m -c 2 -e -l INFO -g"
from recent osmo-trx master ang got following errors with different UHS
version:
linux; GNU C++ version 4.8.4; Boost_105400; UHD_003.010.000.000-release
-- Loading firmware image: /usr/share/uhd/images/usrp_b200_fw.hex...
INFO 3032143616 12:57:24.6 UHDDevice.cpp:786:open: Using discovered UHD
device type=b200,name=MyB210,serial=30AC26A,product=B210
ALERT 3032143616 12:57:25.8 UHDDevice.cpp:790:open: UHD make failed, device
ALERT 3032143616 12:57:25.8 UHDDevice.cpp:790:open: UHD make failed, device
ALERT 3032143616 12:57:25.8 osmo-trx.cpp:530:main: Failed to create
radio device
ALERT 3032143616 12:57:25.8 osmo-trx.cpp:530:main: Failed to create
radio device
Shutting down transceiver...
linux; GNU C++ version 4.8.2; Boost_105400; UHD_003.008.004-0-unknown
INFO 3036346112 12:51:39.9 UHDDevice.cpp:786:open: Using discovered UHD
device type=b200,name=MyB210,serial=30AC26A,product=B210
-- Operating over USB 2.
-- Initialize CODEC control...
-- Initialize Radio control...
-- Performing register loopback test... pass
-- Performing register loopback test... pass
-- Performing CODEC loopback test... pass
-- Performing CODEC loopback test... pass
-- Asking for clock rate 32.000000 MHz
-- Actually got clock rate 32.000000 MHz
-- Performing timer loopback test... pass
-- Performing timer loopback test... pass
INFO 3036346112 12:51:43.3 UHDDevice.cpp:743:parse_dev_type: Using USRP1
type transmit window for B-Series Device B210
-- Asking for clock rate 3.200000 MHz
UHD Warning:
The requested master_clock_rate 3.200000 MHz exceeds bounds imposed
by UHD.
The master_clock_rate has been forced to 5.000000 MHz.
-- Actually got clock rate 5.000000 MHz
-- Performing timer loopback test... pass
-- Performing timer loopback test... pass
ALERT 3036346112 12:51:45.0 UHDDevice.cpp:546:set_master_clk: Failed to
set master clock rate
ALERT 3036346112 12:51:45.0 UHDDevice.cpp:546:set_master_clk: Failed to
set master clock rate
ALERT 3036346112 12:51:45.0 UHDDevice.cpp:547:set_master_clk: Requested
clock rate 3.2e+06
ALERT 3036346112 12:51:45.0 UHDDevice.cpp:547:set_master_clk: Requested
clock rate 3.2e+06
ALERT 3036346112 12:51:45.0 UHDDevice.cpp:548:set_master_clk: Actual
clock rate 5e+06
ALERT 3036346112 12:51:45.0 UHDDevice.cpp:548:set_master_clk: Actual
clock rate 5e+06
ALERT 3036346112 12:51:45.0 osmo-trx.cpp:530:main: Failed to create
radio device
ALERT 3036346112 12:51:45.0 osmo-trx.cpp:530:main: Failed to create
radio device
Shutting down transceiver...
On 08/11/2016 04:14 AM, Tom Tsou wrote:
On Wed, Aug 10, 2016 at 11:08 AM, Sipos Csaba
<sipos.csaba(a)kvk.uni-obuda.hu> wrote:
Unfortunately, the requirement turns out to be master. I'm
testing a
workaround for prior UHD versions.
-TT
--
Max Suraev <msuraev(a)sysmocom.de> http://www.sysmocom.de/
=======================================================================
* sysmocom - systems for mobile communications GmbH
* Alt-Moabit 93
* 10559 Berlin, Germany
* Sitz / Registered office: Berlin, HRB 134158 B
* Geschaeftsfuehrer / Managing Director: Harald Welte
There is
a UHD version requirement to clock the B200/B210 below 5 MHz
Can you tell which
version it is?
I am using 3.9.4
6:02 p.m.
On Thu, Oct 13, 2016 at 4:00 AM, Max <msuraev(a)sysmocom.de> wrote:
linux; GNU C++ version 4.8.2; Boost_105400;
UHD_003.008.004-0-unknown
...
INFO 3036346112 12:51:43.3
UHDDevice.cpp:743:parse_dev_type: Using USRP1
type transmit window for B-Series Device B210
-- Asking for clock rate 3.200000 MHz
UHD Warning:
The requested master_clock_rate 3.200000 MHz exceeds bounds imposed
by UHD.
The master_clock_rate has been forced to 5.000000 MHz.
The 3.2 MHz setting was used to get around a timestamp conversion bug
in UHD, but that's not supported in versions below 3.9.0. I don't like
to keep raising the minimum UHD requirement, but that seems to be the
best choice in the current situation.
-TT
10 Aug
10 Aug
2:17 p.m.
Ok, with
sudo chrt 15 ./src/osmo-bts-trx/osmo-bts-trx -t 2 -c
~/.config/osmocom/osmo-bts-mtrx.cfg -d DRTP:DCC:DRSL:DL1C
it starts but phone fails to see the network - openbsc gives following
error:
<0004> bsc_init.c:287 bootstrapping RSL for BTS/TRX (0/0) on ARFCN 878
using MCC=1 MNC=64 LAC=1 CID=0 BSIC=63
<001d> input/ipa.c:265 accept()ed new link from 192.168.122.1 to port 3003
<0004> bsc_init.c:287 bootstrapping RSL for BTS/TRX (0/1) on ARFCN 880
using MCC=1 MNC=64 LAC=1 CID=0 BSIC=63
<0000> abis_rsl.c:1835 (bts=0,trx=1,ts=0,ss=0) ERROR INDICATION
cause=SABM frame with information not allowed in this state in state=ACTIVE
<0002> gsm_04_08.c:472 Subscriber 1640000005666: LOCATION UPDATING
REJECT LAC=1 BTS=0
<0002> gsm_subscriber.c:309 Subscriber 1640000005666 ATTACHED LAC=1
<001d> input/ipaccess.c:277 Bad signalling message,sign_link returned error
<001d> input/ipaccess.c:277 Bad signalling message,sign_link returned error
<0000> abis_rsl.c:1835 (bts=0,trx=1,ts=0,ss=0) ERROR INDICATION
cause=Timer T200 expired (N200+1) times in state=RELEASE REQUESTED
Could you share which versions/branches have you used in your tests?
Also could elaborate on '-m' - what's this option for and when it's
necessary? How it's support to affect osmo-bts configuration?
On 08/02/2016 12:39 AM, Tom Tsou wrote:
Hi Max,
On Mon, Aug 1, 2016 at 7:57 AM, Max <msuraev(a)sysmocom.de> wrote:
--
Max Suraev <msuraev(a)sysmocom.de> http://www.sysmocom.de/
=======================================================================
* sysmocom - systems for mobile communications GmbH
* Alt-Moabit 93
* 10559 Berlin, Germany
* Sitz / Registered office: Berlin, HRB 134158 B
* Geschaeftsfuehrer / Managing Director: Harald Welte
I've asked about it before but this seems to
have been lost in
communication.
I do not recall this discussion. My apologies.
The question is basically how to enable multi-TRX
support for
osmo-bts-trx using phy/instance infrastructure similar to other bts?
I use the
following configuration.
phy 0
instance 0
instance 1
osmotrx rx-gain 25
bts 0
band 900
ipa unit-id 1234 0
oml remote-ip 127.0.0.1
settsc
gsmtap-sapi ccch
gsmtap-sapi pdtch
trx 0
phy 0 instance 0
trx 1
phy 0 instance 1
$ osmo-bts-trx -c osmo-bts.cfg -t 2
In short, I'd like to configure OpenBSC with
1 BTS with 2 TRX, each with
its own arfcn and set of channels. I'm running "osmo-bts-trx -t 2" and
correspondingly "osmo-trx -c 2" on usrp b210. Any ideas on what's
missing to make this actually work are greatly appreciated.
You can use
"osmo-trx -c 2" or "osmo-trx -m -c 2" to use dual-channels
of the B210 or multi-ARFCN on one channel respectively.
Note that there are ARFCN restrictions for both cases. Due to a shared
local oscillator for both B210 channels, ARFCN separation can be up
about 25 MHz.
With multi-TRX, ARFCN spacing is fixed at 800 kHz or 4 GSM channels.
So if TRX-0 is set to ARFCN 51, TRX-1 _must_ be set to 55. Up to three
ARFCN's is supported for multi-TRX.
-TT
5:35 p.m.
On Wed, Aug 10, 2016 at 7:17 AM, Max <msuraev(a)sysmocom.de> wrote:
<0002> gsm_subscriber.c:309 Subscriber
1640000005666 ATTACHED LAC=1
<001d> input/ipaccess.c:277 Bad signalling message,sign_link returned error
<001d> input/ipaccess.c:277 Bad signalling message,sign_link returned error
<0000> abis_rsl.c:1835 (bts=0,trx=1,ts=0,ss=0) ERROR INDICATION
cause=Timer T200 expired (N200+1) times in state=RELEASE REQUESTED
Could you share which versions/branches have you used in your tests?
I was using master branch at the time. I will test with more recent
master branch updates later today.
Also could elaborate on '-m' - what's this
option for and when it's
necessary? How it's support to affect osmo-bts configuration?
There are two ways to implement multi-ARFCN with the B210 - using
independent, direct channels for each ARFCN and mutiplexing multiple
ARFCN's onto a single RF channel.
The direct approach uses separate physical channels of the B210 (one
ARFCN each for side A and side B). Note that channels are not 100%
independent on the B210 because they share a single local oscillator
(LO). For that reason ARFCN channel separation is limited to roughly
25 MHz. This is the configuration if '-m' is not specified.
The 'multi-carrier' approach multiplexes up to 3 ARFCN channels onto a
single physical RF channel (side A) on the B210. Channel spacing is
fixed at 800 kHz, or 4 ARFCN channels. ARFCN settings from OpenBSC
must match accordingly. The '-m' option enables this configuration.
Also note that the above configurations cannot be combined.
-TT
11 Aug
11 Aug
9:50 a.m.
Thanks for the explanation. See some comment inline.
On 08/10/2016 07:35 PM, Tom Tsou wrote:
The 'multi-carrier' approach multiplexes up to 3 ARFCN channels onto a
single physical RF channel (side A) on the B210. Channel spacing is
fixed at 800 kHz, or 4 ARFCN channels. ARFCN settings from OpenBSC
must match accordingly. The '-m' option enables this configuration.
Could you give an example of necessary openbsc and osmo-bts
configuration for both cases?
Also note that the above configurations cannot be
combined.
So I should not run "./Transceiver52M/osmo-trx -c 2 -g -m"?
Only "./Transceiver52M/osmo-trx -c 2 -g" or "./Transceiver52M/osmo-trx
-g -m"?
Or you referring to the incompatibility of configuration of openbsc? Or
Osmobts?
-TT
--
Max Suraev <msuraev(a)sysmocom.de> http://www.sysmocom.de/
=======================================================================
* sysmocom - systems for mobile communications GmbH
* Alt-Moabit 93
* 10559 Berlin, Germany
* Sitz / Registered office: Berlin, HRB 134158 B
* Geschaeftsfuehrer / Managing Director: Harald Welte
12 Aug
12 Aug
7:05 p.m.
On Thu, Aug 11, 2016 at 2:50 AM, Max <msuraev(a)sysmocom.de> wrote:
You cannot support, for example, 6 ARFCN operation on B210 using 3 TRX
on side A and another 3 TRX on side B.
Whether you use '-c 2 -m' or just '-c 2' depends on whether you want
to feed two ARFCN channels through 1 or 2 PA's respectively.
-TT
On 08/10/2016 07:35 PM, Tom Tsou wrote:
Config files and README are attached. Note that the osmo-trx
multi-carrier '-m' option requires UHD master. I'm still backporting
the needed settings.
The 'multi-carrier' approach multiplexes
up to 3 ARFCN channels onto a
single physical RF channel (side A) on the B210. Channel spacing is
fixed at 800 kHz, or 4 ARFCN channels. ARFCN settings from OpenBSC
must match accordingly. The '-m' option enables this configuration.
Could you give an example of necessary openbsc and osmo-bts
configuration for both cases? Also note that
the above configurations cannot be combined.
So I should not run "./Transceiver52M/osmo-trx -c 2 -g -m"?
Only "./Transceiver52M/osmo-trx -c 2 -g" or "./Transceiver52M/osmo-trx
-g -m"?
Or you referring to the incompatibility of configuration of openbsc? Or
Osmobts?
13 Oct
13 Oct
2:34 p.m.
Hi.
After updating uhd to UHD_003.010.000.000-release I got it partially
working. It's summarized in https://projects.osmocom.org/issues/1648
If I understood correctly there are 2 possibilities for multi-trx setup
with osmo-trx: multiplexed and non-multiplexed. The command to run
osmo-bts-trx is the same in both cases: you've got to specify number of
trx like in "./src/osmo-bts-trx/osmo-bts-trx -c
~/.config/osmocom/osmo-bts-mtrx.cfg -t 2". From osmo-trx, the difference is:
non-multiplexed: ./Transceiver52M/osmo-trx -c 2 -l INFO
multiplexed: ./Transceiver52M/osmo-trx -m -c 2 -l INFO
The question is - is there any difference between multiplexed and
non-multiplexed mode for osmo-bts-trx config file? I've got multiplexed
mode working with following setup:
...
phy 0
instance 0
instance 1
...
trx 0
phy 0 instance 0
trx 1
phy 0 instance 1
...
Should it look differently for non-multiplexed mode? Are there some
other command-line options or config files adjustments missing to make
non-multiplexed mode working? Did I got the overall setup right?
On 08/12/2016 09:05 PM, Tom Tsou wrote:
On Thu, Aug 11, 2016 at 2:50 AM, Max
<msuraev(a)sysmocom.de> wrote:
You cannot support, for example, 6 ARFCN operation on B210 using 3 TRX
on side A and another 3 TRX on side B.
Whether you use '-c 2 -m' or just '-c 2' depends on whether you want
to feed two ARFCN channels through 1 or 2 PA's respectively.
-TT
--
Max Suraev <msuraev(a)sysmocom.de> http://www.sysmocom.de/
=======================================================================
* sysmocom - systems for mobile communications GmbH
* Alt-Moabit 93
* 10559 Berlin, Germany
* Sitz / Registered office: Berlin, HRB 134158 B
* Geschaeftsfuehrer / Managing Director: Harald Welte
On 08/10/2016 07:35 PM, Tom Tsou wrote:
Config files and README are attached. Note that the
osmo-trx
multi-carrier '-m' option requires UHD master. I'm still backporting
the needed settings.
The 'multi-carrier' approach multiplexes
up to 3 ARFCN channels onto a
single physical RF channel (side A) on the B210. Channel spacing is
fixed at 800 kHz, or 4 ARFCN channels. ARFCN settings from OpenBSC
must match accordingly. The '-m' option enables this configuration.
Could
you give an example of necessary openbsc and osmo-bts
configuration for both cases? Also note
that the above configurations cannot be combined.
So I should not run
"./Transceiver52M/osmo-trx -c 2 -g -m"?
Only "./Transceiver52M/osmo-trx -c 2 -g" or "./Transceiver52M/osmo-trx
-g -m"?
Or you referring to the incompatibility of configuration of openbsc? Or
Osmobts?
6:16 p.m.
On Thu, Oct 13, 2016 at 7:34 AM, Max <msuraev(a)sysmocom.de> wrote:
The question is - is there any difference between
multiplexed and
non-multiplexed mode for osmo-bts-trx config file? I've got multiplexed
mode working with following setup:
...
phy 0
instance 0
instance 1
...
trx 0
phy 0 instance 0
trx 1
phy 0 instance 1
...
I used the same configuration.
Should it look differently for non-multiplexed mode?
Are there some
other command-line options or config files adjustments missing to make
non-multiplexed mode working? Did I got the overall setup right?
Multiplexed and non-multiplexed configurations should look the same to
osmo-bts. The main difference will be on ARFCN settings.
Multiplexed (MCBTS) - TRX0 is the primary ARFCN. Channel spacing is
fixed at 4, so TRX1 and TRX2 must be set 4 and 8 ARFCN channels higher
than TRX0 respectively.
Non-multiplexed - ARFCN for each channel can be set within the
limitations of the RF device. This will vary depending on the
particular RF product.
-TT
12 Aug
12 Aug
8:33 p.m.
On 10/08/2016 19:35, Tom Tsou wrote:
There are two ways to implement multi-ARFCN with the
B210 - using
independent, direct channels for each ARFCN and mutiplexing multiple
ARFCN's onto a single RF channel.
oo.. Possible silly question, but then is
this multiplexing single RF
channel mode possible on the N210?
k/
9:07 p.m.
On Fri, Aug 12, 2016 at 1:33 PM, Keith Whyte <keith(a)rhizomatica.org> wrote:
On 10/08/2016 19:35, Tom Tsou wrote:
Not a silly question at all. In fact, it's a very good question.
Yes and no. The N210 device is capable of operating in a similar
configuration, but the implementation is more complicated and, more
importantly, does not exist.
The reason is that the N210 uses a fixed FPGA clocking frequency that
doesn't match up well with the polyphase channelizer used for
multiplexing. The B200/B210 has configurable clocking so that the
desirable sampling rate for GSM channel spacing can be used.
-TT
There are two ways to implement multi-ARFCN with
the B210 - using
independent, direct channels for each ARFCN and mutiplexing multiple
ARFCN's onto a single RF channel.
oo.. Possible silly question, but then is
this multiplexing single RF
channel mode possible on the N210?
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Tom Tsou