Let's disable category here since we don't care about its formatting here.
In any case, every test relying on logging output validation should
always explicitly state the config to avoid issues in the future if
default values change.
Change-Id: I8713f4e04e92b4d7e211c499fc6e78983edfb139
Related: OS#5034
The only reason why it was not 'const' is that in lchan_new_ul_meas()
we may need to overwrite 'ulm->is_sub'. This can still be done after
memcpy()ing a new set of samples to the destination buffer.
Change-Id: I0cabf75f8e0bf793c01225a4a8433e994c93f562
Related: OS#5024
One part of the algorithm simply provides a _suggested_ 'delta' that
needs to be applied to the current power level, while the other part
ensures that this suggested value does not exceed the limits. Thus
it's possible that some logging messages would state that the power
reduction value remains unchanged, while the 'detla' != 0.
Change-Id: I7496a158b9ac6074a965056d708d8078a98cb1aa
Related: SYS#4918
This change makes BS power control loop:
- take the lower RxQual threshold (L_RXQUAL_XX_P) into account, so
the BS power is increased only if RxQual exceeds this threshold;
- apply the configured increase step size instead of reducing the
current attenuation by half.
MS power loop is not affected, it does not even handle RxQual yet.
Change-Id: Ib3c740b9a0f3ba5dfb027e144dc13f456cb26ae2
Related: SYS#4918
It makes more sense to use a reduce step size that is smaller than
the increase step size. This way both MS/BS power control loops
would be able to react quickly of the signal gets weaker, while
the good signal would not trigger radical power reduction.
Change-Id: Ie358fd828a68bfa1d23559197e8df8478fb4535e
Related: SYS#4918
In change [1] the new power control structures and default params
were introduced. In change [2], the existing VTY commands for MS
power control in the BTS were deprecated and changed to use the
new structures as storage. Finally, in change [3], handling of
the power control parameters on the A-bis/RSL was implemented.
This change is the final logical step in the mentioned chain: it
makes both MS/BS power control loops use the new parameters, and
removes the old structures. The actual implementation of both
power control loops remains the same, however the expected output
of some unit tests for the Downlink loop needs to be changed:
- TC_fixed_mode: disabling dynamic power control becomes a separate
step of the test script since the field 'fixed' is removed;
- TC_rxlev_target: RxLev thresholds are printed 'as-is'.
Not all of the new parameters are used by the power control loops
yet. Further improvements to be done in the follow up commits.
[1] I6d41eb238aa6d4f5b77596c5477c2ecbe86de2a8
[2] Icbd9a7d31ce6723294130a31a179a002fccb4612
[3] I5a901eca5a78a0335a6954064e602e65cda85390
Change-Id: Ib18f84c40227841d95a36063a6789bf63054fc2e
Related: SYS#4918
We already have MS Power Control, which according to 3GPP 45.008
shall be implemented in the MS to minimize the transmit power in
the Uplink direction. The BS Power Control may optionally be
implemented by the network side for the same purpose.
Using Downlink signal measurements reported by the MS, the BSS
(either BSC, or BTS) may control Downlink attenuation in a way
that the transmit power remains as low as possible, or remains
in a specific range corresponding to good RxLev values on the
MS side. This change implements autonomous BS Power Control,
that can optionally be enabled by the BSC.
BS Power Control re-uses parts of the MS Power Control code,
so all parameters can be configured in the same way - via the
VTY interface or a configuration file. This basically means
that features like hysteresis and EWMA based filtering are
also available for BS Power Control.
The only difference is that RxQual values higher than 0 would
trigger the logic to reduce the current attenuation twice.
Note that one of the unit tests ('TC_rxlev_max_min') fails,
as the power step limitations for raising and lowering look
wrong to me, and the related discussion is still ongoing.
Change-Id: I5b509e71d5f668b6b8b2abf8053c27f2a7c78451
Related: SYS#4918
Similar to I3c07cb6e14acd5a988761bbc51a9c3b60fb22d87, this change
is another step towards separating the common delta calculation
logic from lchan_ms_pwr_ctrl(), since this function will loose
access to the averaged values.
On the one hand, the affected logging statements are getting
less precise; on the other, logging the averaged value as the
actual value ('rx-current') may be even more confusing.
Change-Id: I07007e45c859b4080fbbe520ffb5ccc0bb9c4244
Related: SYS#4918
This change would allow to separate the common logic from
lchan_ms_pwr_ctrl() and re-use it for Downlink power control.
The logging statement was quite useful during early stages
of development and testing of hysteresis and filtering,
but now we can sacrifice it.
Change-Id: I3c07cb6e14acd5a988761bbc51a9c3b60fb22d87
Related: SYS#4918
This would allow to pass only two pointers:
- 'struct bts_power_ctrl_params', and
- 'struct lchan_power_ctrl_state',
and get rid of 'struct gsm_lchan' dependency. The later is
exactly where all state variables are supposed to be kept.
Change-Id: Idfefca30f4944bc722b4e9d8f1685eb77670a9db
Related: SYS#4918
The logic in measurement.c checks the amount of collected measurement
values. This is done for the total amount of measurements and the amount
of SUB blocks measurements.
The functions that return the expected number of measurement values
currently do not take into account that the mode of a TCH/F or TCH/H has
an effect on the number of expected SUB blocks. (In signalling channels
all blocks count as SUB). Also a TCH/H in signalling mode generates only
half the amount of measurements because the blocks in signalling mode
are sepreded over 6 bursts instead of 4. This also needs to be taken
into account.
Change-Id: I01c7b6cc908c647263ab88f6b6281c4732f88779
Related: OS#4799
Recently we've introduced EWMA based uplink power filtering, that
should reduce Uplink power oscillations. However, the power loop
is still quite sensitive to small deviations from the target power
level: even such an insignificant deviation like 2-5 dBm triggers
the loop to increase or decrease the MS power level. Even if the
EWMA based filtering is enabled with 80% smoothing (alpha = 0.2).
This change introduces a new configuration parameter - 'hysteresis':
uplink-power-target <-110-0> hysteresis <1-25>
that together with the 'uplink-power-target' defines a range:
[target - hysteresis .. target + hysteresis]
in which the MS power loop would not trigger any power changes.
This feature is now *enabled* by default, so given that:
- default 'uplink-power-target' is -75 dBm, and
- default 'hysteresis' is 3 dBm,
the default target Uplink power range is: -78 dBm ... -72 dBm.
Change-Id: Iacedbd4d69d3d74e2499af5622a07a8af0423da0
Related: SYS#4916
It makes no sense to do further calculations if the actual Uplink
signal strength equals the target value configured in the VTY.
Change-Id: Id99c7013a722403e773df8367b1a9d7a856e639b
Related: SYS#4916
So far the Uplink power control loop did not filter the Uplink RSSI
measurements (reported by the BTS) at all. The lack of filtering
makes our implementation too quick on the trigger, so in the real
deployments there will be unneeded Tx power oscillations.
In order to reduce this effect, let's implement a very simple EWMA
(also known as Single Pole IIR) filtering that is defined as follows:
Avg[n] = a * Pwr[n] + (1 - a) * Avg[n - 1]
where parameter 'a' determines how much weight of the latest UL RSSI
measurement result 'Pwr[n]' carries vs the weight of the average
'Avg[n - 1]'. The value of 'a' is usually a float in range 0 .. 1, so:
- value 0.5 gives equal weight to both 'Pwr[n]' and 'Avg[n - 1]';
- value 1.0 means no filtering at all (pass through);
- value 0.0 makes no sense.
This formula was further optimized with the use of '+=' operator.
The floating point math was also eliminated by scaling everything
up (by 100). For more details, see:
https://en.wikipedia.org/wiki/Moving_averagehttps://en.wikipedia.org/wiki/Low-pass_filter#Simple_infinite_impulse_response_filterhttps://tomroelandts.com/articles/low-pass-single-pole-iir-filter
The EWMA filtering is now *enabled by default*, but can be disabled
or (re-)configured over the VTY at any time:
! Completely disable filtering
no uplink-power-filtering
! Enable EWMA smoothing with the given parameters
uplink-power-filtering algo ewma beta <1-99>
Note that the VTY command expects 'beta' instead of 'alpha':
alpha = (100 - beta)
and the value must be in %. This is done for simplicity:
1% means lowest smoothing,
99% means highest smoothing.
Let's say we have EWMA filtering enabled with alpha = 0.4, and get
-98 dBm on the input, while the last output value was -60 dBm.
The new output would be:
Avg[n] = 0.4 * Pwr[n] + 0.6 * Avg[n - 1]
Avg[n] = (0.4 * -98) + (0.6 * -60)
Avg[n] = -75.2 => around -75
Of course, this is not a silver bullet, but better than nothing.
Change-Id: Ib6dcadbf14ef59696c6a546bd323bda92d399f17
Related: SYS#4916
See previous commit adding the unit test about the error description and
expected behavior.
The wrong behavior appeared due to step_size_mdB being unsigned and the
whole addition at the left side of the comparison being turned too as
unsigned, hence a small negative value turning into a big positive
value, and tpp->p_total_cur_mdBm not being updated to speed up the power
ramping.
Change-Id: I36a34362ebc90226fd8e1e190f898c3718fd923a
The test code is extended to support testing more than one ramping loop.
A new test ramping test is added, which shows buggy behavior, since
being in -10dBm and targeting 10dBm with max_initial_pout_mdBm=0 should
immediatelly jump -10->0 and then slowly ramp up (2dB) 0->10dB.
The issue will be fixed in next commit.
Change-Id: I5adc9008ac415eb23274755fc8270df8eebdc6fb
Some backends like osmo-bts-trx require exchanging messages like
POWEROFF to close the TRX, and hence need some time. Switch the function
to expect result asynchronously by calling a callback.
This will be used later to wait until all TRX are really powered off
before exiting the process.
Change-Id: I7d76b600fc06e1114b35bf0c2d08eff5bbd1b69a
According to 3GPP TS 08.58, section 9.3.4, BS Power IE indicates
the transmission power attenuation on a particular channel:
+--------------+---------+-----------------+
| Reserved (3) | FPC (1) | Power level (4) |
+--------------+---------+-----------------+
so let's change handling of this IE as follows:
- s/bs_power/bs_power_red/g, so it reflects 'reduction';
- store power attenuation value in dB, not in 2 db steps;
- get rid of ms_power_ctrl.bts_tx_pwr, it's always 0 anyway;
- fix rsl_tx_meas_res(): use lchan->bs_power_red;
- always check if FPC (Fast Power Control) flag is set;
- we don't support it, so reject messages containing it;
- fix rsl_rx_chan_activ(): properly apply the bitmask.
Change-Id: I16cc50dfca102030380a06e16c234d5f6698f38f
It was a very bad idea to mix "public" BTS features, that are
reported to the BSC via OML, and those features, that are used
locally (and exclusively) in osmo-bts.
Why? At least because we already have the BTS feature manipulation
API in libosmocore, that is used by osmo-bsc, but for some reason
not by osmo-bts. New features added to libosmocore would clash
with the existing "internal" ones like BTS_FEAT_MS_PWR_CTRL_DSP.
So what this change does can be described as follows:
- remove duplicate definition of the "public" features,
- use libosmocore's API for the "public" features,
- separate both "internal" and "public" features:
- the "public" features continue to live in bitvec,
- the "internal" features become flags,
- s/BTS_FEAT/BTS_INTERNAL_FLAG/g.
Change-Id: Icf792d02323bb73e3b8d46384c7890cb1eb4731e
The function ts45008_83_is_sub rougly decides if a frame is a SUB frame
or not. This works by checking the frame number against against lookup
tables. This works fine for codecs where the occurrence of SUB frames is
fixed. However for AMR this is not the case as the DTX periods are
dynamic. Here it is the responsibility of the lower layers (phy,
frame decoding) to tag SUB frames early since making the decision later
based on the frame number is not possible.
The parameter is_amr_sid_update was probably added as a placeholder. It
is set to falls by the callers of the function. Lets remove this
parameter as a late decision if an AMR frame is a SUB frame will never
work.
Change-Id: I125d5ff592218a9e98130a6a7b6bbc6378ce4132
Related: OS#2978
/usr/bin/ld: /home/laforge/projects/git/osmo-bts/tests/sysmobts/../../src/osmo-bts-sysmo/tch.c:584: undefined reference to `femtobts_tch_pl_names'
/usr/bin/ld: l1_transp_hw.o:/home/laforge/projects/git/osmo-bts/src/osmo-bts-sysmo/femtobts.h:108: multiple definition of `pdch_msu_size'; main.o:/home/laforge/projects/git/osmo-bts/src/osmo-bts-sysmo/femtobts.h:108: first defined here
/usr/bin/ld: l1_transp_hw.o:/home/laforge/projects/git/osmo-bts/src/osmo-bts-sysmo/femtobts.h:71: multiple definition of `femtobts_l1prim_type'; main.o:/home/laforge/projects/git/osmo-bts/src/osmo-bts-sysmo/femtobts.h:71: first defined here
see also: https://alioth-lists.debian.net/pipermail/debian-mobcom-maintainers/Week-of-Mon-20200413/000651.html
Change-Id: I4a9896153876fcda496365776883827746205f00
The variable irssi_full_sum is not populated with a dummy value when we
are not able to compute irssi_full_sum. Instead we mistakenly write
MEASUREMENT_DUMMY_IRSSI to ber_full_sum, which is wrong
Change-Id: I44d7cb48e3c68ab1b48c78cceb9381ce3e39d7e8
Related: OS#2987
The timing advance controller that is implemented in loops.c of
osmo-bts-trx only works for osmo-bts-trx and not for any of the phy
based bts. Lets move the timing advance controller into the common part
and make it available for every bts. Also lets add a unit-test.
Change-Id: If7ddf74db3abc9b9872abe620a0aeebe3327e70a
Related: SYS#4567
It's not a good idea to request big changes in MS Power based on
sporadic bad signal received, let's instead change announced MS power
levels more smoothly to avoid possible big signal strength fluctations,
similar to what is already done in osmo-bts-trx specific loop (loops.c).
Related: OS#1851
Change-Id: Iecc4ec7e21471ec853ad2d5659af4052aba5444c
Pau Espin
Vadim Yanitskiy
Philipp Maier
Harald Welte