It may happen that one or more Downlink bursts are lost on their
way to the MS due to a variety of reasons. Modern transceivers
supporting TRXDv1 protocol would substitute lost bursts with
so-called NOPE indications. Hovewer, neither fake_trx.py nor
grgsm_trx do support this feature at the moment.
We can still detect and compensate TDMA frame loss per logical
channels in the same way as it's already done in osmo-bts-trx.
In short, we should keep TDMA frame number of the last received
burst in the logical channel state, and using the appropriate
multiframe layout, check if there were any gaps between TDMA
frame number of the current burst and the stored one.
Change-Id: I3551d79796a3730565c2c70577e9d134e636f275
Using TDMA frame number of a burst with bid=0 is fine for xCCH,
but not for TCH and FACCH, because they use the block-diagonel
interleaving. A single block on TCH may be interleaved over
8, 4 or even 6 consecutive bursts depending on its type.
Since we now have the measurement history, we can attach TDMA
frame number to each measurement set, and then look up N-th
one when averaging the measurements in sched_trx_meas_avg().
Change-Id: I9221957297a6154edc1767a0e3753f5ee383173f
This allows us to bind the multicast sockets to a given network device
and/or to set the TTL of the multicast frames and hence control their
reach in terms of number of network hops.
Change-Id: Ia74aa381a4c1921cb8c7e263842a864ea8028139
Related: OS#2966
The files are used in both projects, and while the osmo-bts code has
evolved, this copy didn't. Let's sync again (to libosmocore
change-Id I303f2e616d2d32b5a8005c3dcf0f5fad19ad3445).
Change-Id: I189ee28a85a6d7a7a07b062f6b07012478503e8f
Depends: libosmocore.git Ib52d22710020b56965aefcef09bde8247ace4a9c
Related: OS#2966
In case we get assignments to secondary TRXs, the ARFCN of that
TRX must be used, and not the serving cell BCCH ARFCN.
Change-Id: Ief6cf5816969d819ff9506be70bec9b8d0d9d9be
GSMTAP_CHANNEL_VOICE is the mechanism by which GSMTAP can [finally!]
be used to transport circuit-switched voice codec payload, and not
just signalling.
Original patch by Neels Hofmeyr, heavily extended by Harald Welte.
Change-Id: Id72cf23b7c6587efae4cdaa7b50ab4d85b8c8d22
These BFI (Bad Frame Indications) substitute speech frames stolen
by FACCH/F or FACCH/H frames, so there can be no bit errors in
something that was not even transmitted over the air interface.
Change-Id: Icdb6209f75ead6581e3c18aeee0da9831aaa272a
According to 3GPP TS 45.003, clauses 4.2.5 and 4.3.5:
- one FACCH/F frame steals a single speech frame,
- one FACCH/H frame steals two speech frames.
A BFI (Bad Frame Indication) needs to be sent for each stolen
speech frame. This does not apply to CSD (data) channels though.
The BFI frames must have measurement data attached to them, and
due to their virtual nature (they do not actually come from the
air interface), the measurements must be crafted by trxcon.
Assigning a negative value to n_errors makes the code below the
'bfi' label craft fake measurement data. Otherwise, the actual
measurements belonging to the FACCH frame will be used.
Change-Id: Ia2f7c3cf7b1ef3737da6b1818cae2f001ee8768f
So far we used to store the sums of ToA and RSSI measurements in the
logical channel state, and after decoding of a block, we did calculate
the average. This approach works fine for xCCH and PDTCH, but when it
comes to block-diagonal interleaving (which is used on TCH/F and TCH/H
channels), the results are incorrect. The problem is that a burst on
TCH may carry 57 bits of one encoded frame and 57 bits of another.
Instead of calculating the sum of measurements on the fly, let's push
them into a circular buffer (the measurement history), and keep them
there even after decoding of a block. This would allow us to calculate
the average of N last measurements depending on the interleaving type.
A single circular buffer can hold up to 8 unique measurements, so the
recent measurements would basically override the oldest ones.
Change-Id: I211ee3314f0a284112a4deddc0e93028f4a27cef
In Change-Id Ia94ebf22a2ec439dfe1f31d703b832ae57b48ef2 we
introduced a new member to the ccch_mode enum: CCCH_MODE_COMBINED_CBCH,
which is to be used to tell the PHY if a CBCH is present on the combined
CCCH+SDCCH/4+CBCH or not (CCCH+SDCCH4).
This was implemented in trxcon + calypso firmware, but cbch_sniff has
not been updated accordingly.
Related: OS#4439
Change-Id: I429d45cfb181da4a2e767e92f1213ccd08c6d440
Doing so can create a number of warning messages in e.g. 'mobile'
like
<0015> lapd_core.c:1239 Unnumbered frame not allowed. (dl=0x55c632f9f220)
<0015> lapd_core.c:392 sending MDL-ERROR-IND cause 12 from state LAPD_STATE_IDLE (dl=0x55c632f9f220)
<0015> lapdm.c:481 sending MDL-ERROR-IND 12
<0001> gsm48_rr.c:4977 MDL-Error (cause 12) ignoring
Change-Id: I2cf65be5b2f879fe940e08c9f369bc1cada7b0dd
Closes: OS#4439
We so far relied on it being free'd once the TDMA item is free'd,
but let's make it more explicit. After we've unlinked it from the
list, nobody is going to reference it ever again.
Change-Id: I57a596428be10ce720e0b528ecfc44a70e3e3078
That function encapsulates the RTP payload in an MNCC header, but the l1ctl dl
header has to be removed first to get only the RTP payload in the MNCC
structure.
Change-Id: Id6ddc9b1da43e88c5b9468d4397a39953bdf533a
This pointer cs->si stores an address to the System Information of
a currently selected cell. When we release System Information,
ensure that it does not point to free()d memory.
Change-Id: Ife2ddf7274a48447a9ded9035f9dd01befaf2e6c
Some applications (e.g. ccch_scan) may not initialize ms->cellsel.si,
some (e.g. mobile) may need some time to initialize it. Let's assume
that 'bs_ag_blks_res' is 1 if System Information is not available.
Change-Id: Ie695d9700c01ee1e6778950a2f3c8610b69d2143
During 3.19->3.20 dev cycle, some fields were transformed from
timestamp_t or double to timespec_t. See for instance gpsd.git
f7c230fceb6d64483757f8c32afb98e6a2cb9413.
Change-Id: Ie8ba19d030b6f46f2d8afc270a732ce8c26c438f
In several code paths we put / push structures from 'gsm48_mm.h' into
the message buffers, so then they're unpacked by the message receivers.
The AddressSanitizer complains about unaligned pointer access and
potentially unexpected behaviour. Let's fix this by explicitly
marking those structures as 'packed'.
Change-Id: I6af7475c609b3293af708540d569fe1616fab43f
In some cases (e.g. at start up) ms->rrlayer may not be initialized.
Let's access ms->settings directly since we already have a pointer
to struct osmocom_ms.
Change-Id: Ia9720132fcda960dcecefab9ae48398946503dc4
Due to recent include dependency tree change in libosmocore, trxcon
fails now to build since it uncovered it's missing a header inclusion
for a symbol it is using:
osmocom-bb/src/host/trxcon/sched_trx.h:204:20: error: ‘GSM_MACBLOCK_LEN’ undeclared here (not in a function)
204 | uint8_t mr_cache[GSM_MACBLOCK_LEN];
| ^~~~~~~~~~~~~~~~
Change-Id: Ide22e525c106342b00171a8c08bb7265d19a651b
This feature may be useful for our TTCN-3 testing infrastructure.
By default it's disabled, and can be enabled using command line
arguments of the main binary:
./trxcon -g 127.0.0.1 ...
Change-Id: Iab4128fee5f18d816830fdca6c5ebebaf7451902
According to 3GPP TS 45.010, section 5.6.2, for packet-switched
channels the BTS shall monitor the delay of the Access Bursts
sent by the MS on PTCCH and respond with timing advance values
for all MS performing the procedure on that PDCH.
According to 3GPP TS 45.002, section 3.3.4.2, PTCCH (Packet Timing
advance control channel) is a packet dedicated channel, that is
used for continuous Timing Advance control (mentioned above).
There are two sub-types of that logical channel:
- PTCCH/U (Uplink): used to transmit random Access Bursts
to allow estimation of the Timing Advance for one MS in
packet transfer mode.
- PTCCH/D (Downlink): used by the network to transmit
Timing Advance updates for several MS.
As per 3GPP TS 45.003, section 5.2, the coding scheme used for
PTCCH/U is the same as for PRACH as specified in subclause 5.3,
while the coding scheme used for PTCCH/D is the same as for
CS-1 as specified in subclause 5.1.1.
The way we used to handle both PTCCH/U and PTCCH/D is absolutely
wrong - it has nothing to do with xCCH coding. Instead, we need
to use rx_pdtch_fn() for Downlink and tx_rach_fn() for Uplink.
Also, since we only have a shared RSL channel number for PDCH
(Osmocom-specific RSL_CHAN_OSMO_PDCH), there should be a way
to distinguish both PDTCH and PTCCH logical channels. Let's
introduce TRX_CH_LID_PTCCH for that.
Change-Id: I2d1e9b8a66f027047f8d7bdc3f82ff9d8ebcc25e
Since March 15th 2017, libosmocore API logging_vty_add_cmds() had its
parameter removed (c65c5b4ea075ef6cef11fff9442ae0b15c1d6af7). However,
definition in C file doesn't contain "(void)", which means number of
parameters is undefined and thus compiler doesn't complain. Let's remove
parameters from all callers before enforcing "(void)" on it.
Change-Id: I25baaa30b097dad2fae507c5321778f43e863611
Related: OS#4138
According to GSM TS 04.08, section 10.5.4.11, location and coding
standard are encoded before the cause value, not vice-versa!
Also, coding standards other than "1 1 - Standard defined for the
GSM PLMNs" shall not be used if the cause can be represented with
the GSM standardized coding.
Change-Id: Ic6abcfb9a9589f5b0c9c40def863f15ae04d0bdd
Vadim Yanitskiy
Harald Welte
Pau Espin
Martin Hauke