Author Topic: Problems with libusb!!  (Read 8669 times)

marian

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Re: Problems with libusb!!
« Reply #30 on: February 17, 2016, 01:54:14 AM »
Properly calibrating the board would help to have a cleaner signal.
It won't help with your issue.
On earlier log I noticed the transceiver dropped almost all bursts due to low SNR (signal to noise ratio):
ARFCN[0]: Radio power off. RX: bursts=820604 passed=2 (0.00%) dropped=820602 (100.00%) (LowSNR=820500 LowPeakMin=19 LowPower=82 NullRMS=1) ellapsed=473sec avg=1734.89 bursts/sec

Try setting in ybts.conf
[transceiver]
snr_threshold=4

If not working try a greater value.
Most probably the bursts are not ok, but let see what happens...

Jambo

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Re: Problems with libusb!!
« Reply #31 on: February 18, 2016, 09:49:25 AM »
I tried to reconfigure ybts.conf in the proper way and I've managed to gsmtap packets to wireshark.
Actually this does work but I'm not able to understand what happens with GSMTAP packets on localhost.
Should I give you a sample of it?

I've set snr_threshold to 4, 10, 100, 400 but nothing changes.
Anyway what do you specifically mean by 'bursts' and why they're 'not ok'?
Why does this antenna seem to drop them all?
The last try I made I got this:
Code: [Select]
2016-02-18_16:45:28.829099 <gsmtrx:NOTE> ARFCN[0]: Radio power off. RX: bursts=16754 passed=0 (0.00%) dropped=16754 (100.00%) (LowSNR=16754) ellapsed=9sec avg=1861.56 bursts/sec [0xb670ad08]

marian

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Re: Problems with libusb!!
« Reply #32 on: February 19, 2016, 02:02:22 AM »
Can you dump some raw data received from the board?
Just to take a look at it.

Start YateBTS.
Wait a minute.

In telnet console type:
output on
control <device_name> bufoutput tx=false count=20

Type control and then <tab> to let the module complete the device name (usually bladerf/1).
Wait for another minute and repeat the command.

This will output the raw buffer data read from device.
Please post it here.

Jambo

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Re: Problems with libusb!!
« Reply #33 on: February 29, 2016, 10:44:17 AM »
Thanks marian for the reply.
Here's the output of the command with bladerf/1 as device.

http://pastebin.ca/3384950

I think raw data can be seen. What now?

marian

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Re: Problems with libusb!!
« Reply #34 on: March 01, 2016, 02:11:03 AM »
Something is wrong with the data.
I'm not a radio engineer but:
The values are 'linear'.
As you can see the samples have almost the same value.
Something is wrong with the board.

Jambo

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Re: Problems with libusb!!
« Reply #35 on: March 24, 2016, 04:02:26 AM »
Ok, thank you for the reply anyway.
I was guessing if I'm wrong though because I'm trying to connect my phone but my sim's not unlocked.
Could this be the problem?
And if so, is there a way to see my phone's Location Update routine anyway?
(I mean, is there a way to find my phone's IMSI even if I cannot accept it/the phone cannot register to the network?)

marian

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Re: Problems with libusb!!
« Reply #36 on: March 24, 2016, 04:08:02 AM »
In a working scenario you may enable debug on ybts module.
ybts.conf, section [ybts]
print_msg=yes

This will show received messages.
You may see the IMSI in Location Update or Identity Response messages.

andrew77

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Re: Problems with libusb!!
« Reply #37 on: April 25, 2016, 01:50:08 PM »
Ciao Jambo,

ho visto solo ora il tuo messaggio
puoi scrivermi al mio indirizzo di posta personale:
ag001@inwind.it

Andrea



afk

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Re: Problems with libusb!!
« Reply #38 on: November 28, 2017, 03:43:35 AM »
Hello Jambo,

Please try from rmanager (telnet 0 5037) to set 'debug ybts level 9'
It will give you information about the subscriber that wants to attach to the BTS. (There you will have an <imsi> </imsi> field containing the IMSI)


david.burgess

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Re: Problems with libusb!!
« Reply #39 on: November 29, 2017, 06:50:59 AM »
The timestamp jumps usually mean that the CPU is not keeping up with the radio signal. If they are not too severe, YateBTS will still work. If your phone sees the beacon, then it might be OK. You say "a lot" of timestamp jumps? How often do they happen?