RRCTL is a simple protocol (inspired by Osmocom's L1CTL) that allows
an external NAS entity to control the RRC layer of srsUE. The most
notable primitives are PLMN search, selection, and PDU transfer.
The protocol assumes traditional master-slave communication, where
one side (an external NAS entity) initiates various processes,
while the other (srsUE) executes them and indicates the outcome.
Each RRCTL message starts with a header that can be defined as follows:
+-------------------------------+--------------------------+
| Message type | 6 bits |
+-------------------------------+--------------------------+
| Message sub-type | 2 bits |
+-------------------------------+--------------------------+
| Spare (RFU) | 8 bits |
+-------------------------------+--------------------------+
| Payload length | 2 octets (big endian) |
+-------------------------------+--------------------------+
| Payload (optional) | (see payload length) |
+-------------------------------+--------------------------+
The following message types are defined at the moment:
- RRCTL_RESET - reset internal state of the external NAS interface
(does nothing for now, may be useful in the future);
- RRCTL_PLMN_SEARCH - initiates PLMN (carrier) search on pre-configured
EARFCN (Absolute Radio Freqency Number);
- RRCTL_PLMN_SELECT - binds the UE to one of the previously detected
carriers (see RRCTL_PLMN_SEARCH) defined by a
given pair of MCC and MNC;
- RRCTL_CONN_ESTABLISH - establishes connection to the serving cell
(previously selected using RRCTL_PLMN_SELECT)
with a given cause and NAS PDU;
- RRCTL_CONN_RELEASE - releases previously established dedicated connection
(currently does nothing because the RRC layer does
not expose any API for that);
- RRCTL_DATA - encapsulates a received (Downlink) or to be transmitted
(Uplink) NAS PDU (the former also contains LCID).
Each message type has at least two of the following sub-types:
- RRCTL_REQ - request (usually comes from an external NAS entity),
used to initiate some process (e.g. PLMN search);
- RRCTL_IND - indication that something has happened without a prior
request (for example, a Downlink NAS PDU was received);
- RRCTL_CNF - confirmation (positive conslusion) of the requested task;
- RRCTL_ERR - negative conslusion of the requested task (error).
The protocol definition (enums ans structs) and codec functions are
defined in a separate namespaces: 'rrctl::proto' and 'rrctl::codec'
respectively. The codec functions may throw exceptions of type
'rrctl::codec::error' if something goes wrong.
This function does not modify the input buffer. Let's make it
possible to pass 'const uint8_t *' pointers without loosing
the const qualifier and making GCC unhappy.
This function does not modify any fields of the structure. Without
the 'const' qualifier it's impossible to call to_number() through
a const pointer of type 'struct plmn_id_t'.
when releasing PUCCH/SRS (see 5.3.13 in 36.331) we need to reset the SR config as well.
In our case, SR is handled by MAC so we need to (re-)configure MAC, not all of
MAC though, just SR.
- s1 handover composite state simplified
- the eNB now starts a HO cancellation when it receives an invalid
Handover Command
- the FSM log now prints the current state when it receives an unhandled
event
this patch adds a check to drop all PDCP control PDUs
in order to prevent handling them as data PDUs.
This could happen when the size exceeded the arbitrary length check.
This should fix#1787
* Fix deadlock caused by update_measurements calling in_sync
* Fix overlapping SRS condition
* Do not use shortened PUSCH in transmissions and retx from RAR
* Revert "Fix deadlock caused by update_measurements calling in_sync"
This reverts commit f58c8c8c766f8f95baa3a3bf8287d8e25b2057ba.
* Take into account CRS from neigbhour cells when measuring interference
* fix std::isnormal compilation
* Fixed compilation of test
* Address comments
* Remove unused overrides
* Make PHY non-blocking and fefactor HO procedure
* makes entire PHY non-blocking through command interface
* adds dedicated queue for cell_search/cell_select commands
* refactor HO procedure to run faster, in one stack cycle. Looks closer to the specs
* force ue to always apply SIB2 configuration during reestablishment
* Run update_measurements in all workers
Co-authored-by: Ismael Gomez <ismagom@gmail.com>
before epoll can handle signals, the calling thread needs to block
them. the blocking needs to happen before any other threads get
spawned so they inherit the mask.
the Tx SDU has been set to 128 PDUs because this gives approx.
150kByte UL buffer state (max value for Rel 8 BSR).
Previously, however, we've always reported too much pending UL
data because we weren't subtracting the transmitted data from
the reported data.
with this newer BSR reporting, however, even with full buffers we would
never report full buffers because the queues size is too short.
This seems to cause issues for iperf TCP sessions not resulting
in full DL rate, see isse #1703. It seems that the TCP bandwitdh
probing works better with larger buffers (in our case this can
only be achieved with more PDUs in the pool).
This should fix#1703
Vadim Yanitskiy
Sylvain Munaut