Hi,
I was following your mails about your results for the ouput power but I
don't understand how you change it. I was checking the code but I didn't
find how to change TX0 output power.
I tried to change the line :
abis_nm_bs11_set_trx_power(&bts->trx[0], BS11_TRX_POWER_GSM_30mW);
with
abis_nm_bs11_set_trx_power(&bts->trx[0], BS11_TRX_POWER_GSM_250mW);
in the "create_objects" fonction but I don't know how the fonction is
loaded, I don't know how the bs11 enter the state
"BS11_STATE_WAIT_MIN_CFG_2"
case BS11_STATE_WAIT_MIN_CFG_2:
bs11cfg_state = STATE_SWLOAD;
rc = create_objects(g_bts);
break;
If anyone can help me
Thanks a lot
Eric Cathelinaud
Hello,
I try to give a short summary of the MS and BS power settings.
It is not intended to replace the GSM specs, it just contains
the important things for the current BS-11 configuration.
MS power:
- The MS power is usually specified as an absolute value,
a lower value means higher power. Some values for GSM 900
(GSM 1800 has a different encoding):
15 -> 13 dBm (0.02 W)
10 -> 23 dBm (0.2 W)
5 -> 33 dBm (2 W)
- The power used to access the RACH before any channel is active,
is defined by a Cell Selection parameter in SYSTEM INFORMATION
TYPE 3 and 4.
Remark: bsc_hack currently uses "2" which should be increased
(lower power) to avoid interference with the public networks.
- When the BTS activates a channel, it sets the MS power.
bsc_hack currently sets it to 15 which should be OK for testing
(see rsl_rx_chan_rqd() in abis_rsl.c).
- Dynamic power control of the MS power by the BTS is currently
not enabled.
BS power:
- For the BS-11 the PA power can be configured to 0.03W, 0.08W,
0.25W or 2W (b11_config can be used for this purpose).
- The attribute NM_ATT_RF_MAXPOWR_R of each TRX of the BS-11
can be set to a value from 0 (0dB) to 6 (12dB) to reduce
the power in steps of 2dB (see bsc_hack.c).
- for the TRX which carries the BCCH, there is no dynamic
BS power control possible. In the meantime I have read
at several places that the BCCH TRX has to use a fixed power
and additionally cannot use a different ARFCN for example
for the TCH (which also means that no hopping is possible).
To use hopping or dynamic BS power control, the second TRX
has to be used and configured in a way that it does not carry
a BCCH.
Best regard,
Dieter
--
Dieter Spaar, Germany spaar(a)mirider.augusta.de
harald,
i checked the msg_4 array. i found the power info in the description,
but i cannot see where the values are in the array. also i don't really
know the maximum power value for BS11 (GSM 900). is 0db maximum? is it
relative to the BS power class?
> Check
> * the 'MS POWER' attribute in the ACTIVATE CHANNEL
> * the cell selection parameters in SYSTEM INFORMATION TYPE 4 (max tx
power for CCH)
anyway, i found the bug about holding the location update process. i
fixed it, but before i supply a patch, i will check if this really works
when the link fails during location update again.
regards,
andreas
hi,
how can i advice the phone to use the "full" power level according to the power class of the bs11? what parameter and what value is required?
currently we have "kieler woche", an event with up to 3.000.000 visitors over one week.
for the "mobile base station" i use a standard PC with E1/S0 card, a BS11, a laptop, an ISDN phone, and an UPS with 4 * 200Ah batteries.
andreas
-----Ursprüngliche Nachricht-----
Von: Dieter Spaar [mailto:spaar@mirider.augusta.de]
Gesendet: Dienstag, 23. Juni 2009 10:36
An: Andreas.Eversberg
Cc: openbsc(a)lists.gnumonks.org
Betreff: Re: location update problem
Hello Andreas,
On Mon, 22 Jun 2009 19:40:17 +0200, "Andreas.Eversberg" <Andreas.Eversberg(a)versatel.de> wrote:
>
> after location update fails. "DB: Failed to find the Subscriber...", get
> an "ERROR INDICATION" with cause 1. it seems that the mobile just stops
> sending on the channel. the channel ressource hold by location update
> process is not freed. the last messages show that.
>
> i will look on this the next days and report if i found something. if
> you have any idea, please tell me. the way to test any change/fix is
> quite complicated. the bug only occurrs when many phones are available
> and when they move from a different network to my network (built in a
> car, moving arround.)
Just a wild guess: Could it be a reception problem ? If you have set
the BS-11 to a high power level, many phones will see it. Currently the
BS-11 advises the phones to use a very low power level when activating
a channel. So the BS-11 might receive the phone with a low signal
strength and the receiption is just too bad (although the phones will
receive the BS-11 quite well). The measurement reports should indicate
if this is the problem.
Out of interest, do you also have a PC with an E1 card in the car or
do you use a laptop with an USB (or PCMIA) to E1 interface ?
Best regards,
Dieter
--
Dieter Spaar, Germany spaar(a)mirider.augusta.de
Hallo Kai,
On Tue, 23 Jun 2009 14:19:20 +0200, "=?ISO-8859-15?Q?Kai_M=FCnz?=" <squ(a)tent.at> wrote:
>
> There is an even lighter setup possible.
>
> I'm using an old IBM Thinkpad R50p with a Thinkpad DockII (Ebay, 30Eur)
>
> http://www.bildschirmtext.org/thinkpad-e1.jpg
>
> Just connect the BTS and play %)
Nice, and it even has DECT connnectivity (looks like a COM-ON-AIR card
in the background :-)
Best regards,
Dieter
--
Dieter Spaar, Germany spaar(a)mirider.augusta.de
Hello Andreas,
On Tue, 23 Jun 2009 13:30:17 +0200, "Andreas.Eversberg" <Andreas.Eversberg(a)versatel.de> wrote:
>
> picture!
Even more cool :-). I expected a bigger car, maybe a van, to but all
the stuff inside. Really nice GSM war-driving setup ;-)
Best regards,
Dieter
--
Dieter Spaar, Germany spaar(a)mirider.augusta.de
Hello Andreas,
On Tue, 23 Jun 2009 10:12:38 +0200, "Andreas.Eversberg" <Andreas.Eversberg(a)versatel.de> wrote:
>
> how can i advice the phone to use the "full" power level according to
> the power class of the bs11? what parameter and what value is required?
Currently the BS power is set in rsl_rx_chan_rqd() (file abis_rsl.c),
its the "lchan->ms_power" assignment. Currently the value 0x0F (13 dBm)
is used (I am not sure if this is still true for the latest version of
OpenBSC). If you set this value to 0, the MS will use the maximum
power (usually only 5 is supported for GSM900, 2 Watt). I did only
a few tests, but I could see that my phone uses the modified value.
You can of course also look at the measurement report and check the
used values.
> currently we have "kieler woche", an event with up to 3.000.000 visitors
> over one week.
>
> for the "mobile base station" i use a standard PC with E1/S0 card, a
> BS11, a laptop, an ISDN phone, and an UPS with 4 * 200Ah batteries.
Cool, do you have some pictures of the setup ? :-)
Best regards,
Dieter
--
Dieter Spaar, Germany spaar(a)mirider.augusta.de
Hello Andreas,
On Mon, 22 Jun 2009 19:40:17 +0200, "Andreas.Eversberg" <Andreas.Eversberg(a)versatel.de> wrote:
>
> after location update fails. "DB: Failed to find the Subscriber...", get
> an "ERROR INDICATION" with cause 1. it seems that the mobile just stops
> sending on the channel. the channel ressource hold by location update
> process is not freed. the last messages show that.
>
> i will look on this the next days and report if i found something. if
> you have any idea, please tell me. the way to test any change/fix is
> quite complicated. the bug only occurrs when many phones are available
> and when they move from a different network to my network (built in a
> car, moving arround.)
Just a wild guess: Could it be a reception problem ? If you have set
the BS-11 to a high power level, many phones will see it. Currently the
BS-11 advises the phones to use a very low power level when activating
a channel. So the BS-11 might receive the phone with a low signal
strength and the receiption is just too bad (although the phones will
receive the BS-11 quite well). The measurement reports should indicate
if this is the problem.
Out of interest, do you also have a PC with an E1 card in the car or
do you use a laptop with an USB (or PCMIA) to E1 interface ?
Best regards,
Dieter
--
Dieter Spaar, Germany spaar(a)mirider.augusta.de
