Re: [Openbts-discuss] OpenBTS and OsmoTRX - NOHANDOVER message using USRP E310

[Tom T. <tom...@et...>]

Hi Pablo,

On Wed, May 4, 2016 at 12:26 AM, Pablo Colodrón
<pab...@ce...> wrote:
> Device configuration consists of a USRP E310 with the following connections:
> GPS antenna connected to sync signal (GPSDO is locked), GSM antenna
> connected to TRX-A and GSM antenna+40dB attenuator connected to RX2A (for
> preventing RF overrange in RX).

Remove the external attenuator, but set the rxgain setting
appropriately. There is enough gain range on the AD9361 to not require
external attenuation for over the air reception. The exception is if
you connect the UE output to the E310 input directly through a cable;
in that case, external attenuation is necessary.

For the 'rxgain' setting, midpoint is a reasonable starting point. The
log will report when saturation occurs.

> WARNING 3042473040 22:26:06.8 Transceiver.cpp:825:driveControl: NOHANDOVER
> at timeslot 0 subslot 0
> WARNING 3042473040 22:26:06.8 Transceiver.cpp:825:driveControl: NOHANDOVER
> at timeslot 0 subslot 0
>
> Aparrently, they are RACH messages sent by the phone but not processed by
> the transceiver.

Not quite. The NOHANDOVER command is controlled by upper layers of
OpenBTS core and does not indicate reception of RACH bursts.

> root@ettus-e300:/usr/local/bin# ./osmo-trx -f
> linux; GNU C++ version 4.9.1; Boost_105600; UHD_003.008.004-0-unknown

Can you try upgrading to at least UHD 3.9.2 and running the the latest
master for OsmoTRX?

  -TT