This test showcases the current issue where the loop keeps bouncing
between 2 good MS Power Level values due to the loop "accepting" and
"reporting back" the previously considered good MS Power Level
announced/used by the MS. Hence, upon report back from the network, the
MS will switch to this new MS Power Level, and same thing will ocurr
over and over.
Related: SYS#4917
Change-Id: I16ed7fe8a123b99008e0c041d2f3e4232057d55c
TS 45.008 section 4.7.1:
"""
Upon receipt of a command from an SACCH to change its power level on the corresponding uplink channel, the MS
shall change to the new level at a rate of one nominal 2 dB power control step every 60 ms (13 TDMA frames), i.e. a
range change of 15 steps should take about 900 ms. The change shall commence at the first TDMA frame belonging to
the next reporting period (as specified in subclause 8.4). The MS shall change the power one nominal 2 dB step at a
time, at a rate of one step every 60 ms following the initial change, irrespective of whether actual transmission takes
place or not.
"""
Since the reported MS_PWR in L1 SACCH Header is, according to specs, the
one used for the last block of the previous SACCH period, it becomes
clear the first SACCH block after a requested MS Power Level change by
the network may contain mismatches between the announced MS_PWR by the
MS and the measured Rxlev/RxQual. Hence, let's better use a
P_CON_INTERVAL of 1 which retriggers the MS Power Control Loop every second
SACCH block.
Change-Id: If6cb8945645a2031f2b2ee65d9b9f51e75cd9af1
Related: SYS#5371
The bug showed up in previous commit and is fixed in this commit. It can
be seen how rounding error is carried over time in the average
measurement, and affects final values.
Change-Id: I680d1c94bd4bae179b14b26662a819fa1462a5c8
Before this comits, averaging and delta calculation was done in RSSI,
but stored the averaging cached state in variables named "rxlev", which
was really confusing. Let's keeping averaging and delta calculations
based on RxLevels.
Some of the tests change results due to test passing RSSI -45, which is
an invalid Rxlev (only up to -47 is supported).
Others fail due to an unrelated bug showing up now. Basically the averaging algo
is doing rounding the wrong way when downscaling the values. It will be
fixed in a follow-up commit.
Change-Id: I4cff8394f22b5d47789163051364ff594b2bcd74
This commit extends existing MS Power Control Loop algorithm to take
into account computed C/I values on the UL, received from MS. The
related C/I parameters used by the algorithm are configured at and
provided by the BSC, which transmits them to the BTS similar to already
existing parameters.
Using C/I instead of existing RxQual is preferred due to extended
granularity of C/I (bigger range than RxQual's 0-7).
Furthermore, existing literature (such as "GSM/EDGE: Evolution and Performance"
Table 10.3) provides detailed information about expected target values,
even different values for different channel types. Hence, it was decided
to support setting different MS Power Parameters for different channel
types.
These MS Power Parameters are Osmocom specific, ie. supported only by
newish versions of osmo-bts. Older versions of osmo-bts should ignore
the new IEs added just fine. The new IEs containing the MS POwer
Parameters are not send for non osmo-bts BTSs, hence this commit is
secure with regards to running osmo-bsc against an ip.access BTS such
as nanoBTS.
Related: SYS#4917
Depends: libosmocore.git Change-Id Iffef0611430ad6c90606149c398d80158633bbca
Change-Id: I5dfd8ff9ab6b499646498b507624758dcc160fb6
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
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
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
Pau Espin
Vadim Yanitskiy