The purpose is to support RSSI measurements even when we can't decode a burst.
This commit also cleans up and abstracts some of the code in scheduler.c
This is a hack, but it's the easiest way to make BTS level loopback to work.
Another way to implement this is to have BSC/NITB to send the OML command.
Note, that the current code hardcode the channel to be TCH/F which is what we
need for the BER testing.
A known issue with this code is that BER is not updated for lost TCH frames,
because osmo-trx doesn't send any indication for them and we don't have
a callback to handle this.
Otherwise the code seem to work fine.
3GPP TS 05.03 "Channel coding" specifies the puncturing matrix (1,0,1)
for class 1 information bits and tail bits valued u(0) to u(103) for a
maximum puncturing index of 311. The puncturing index 313 exceeds the
maximum index and causes osmo_conv_get_output_length() to output the
improper length of 210 instead of 211.
Signed-off-by: Thomas Tsou <tom@tsou.cc>
If frame number is out of range (>= 2715648), the scheduler's process
would end up in an infinite loop. This is because the loop would schedule
bursts until the indicated frame number is reached, which would not be
possible.
The openbts, calypso-bts and osmo-trx might send out out of range clock
indications every 3.5 hour.
RTS (ready-to-send) must be issued in advance, so BTS core and especially
osmo-pcu can provide downlink data frames early enough. In some cases PCU
might provide frames too late, so they must be dropped. If PCU provides
frames too late, due to high system load, this "RTS advance" setting must
be increased.
Instead of limiting the number of TRX at VTY to the actual number of
supported TRX, VTY allows to configure any possible number of TRX. If a
TRX is configured, which is not supported by BTS model, an error message is
returned, which states that the given TRX is not supported.
Handover and assignment may activate channels with ciphering already set,
so we need to tell scheduler to enable/disable ciphering and set the
correct cipher state.
Alexander Chemeris
Martin Hauke