diff options
| -rw-r--r-- | include/osmocom/bsc/handover_cfg.h | 7 | ||||
| -rw-r--r-- | src/osmo-bsc/handover_decision_2.c | 13 | ||||
| -rw-r--r-- | tests/handover/test_rxqual.ho_vty | 22 | ||||
| -rw-r--r-- | tests/handover_cfg.vty | 3 |
4 files changed, 44 insertions, 1 deletions
diff --git a/include/osmocom/bsc/handover_cfg.h b/include/osmocom/bsc/handover_cfg.h index 2bd26812e..7d68e6317 100644 --- a/include/osmocom/bsc/handover_cfg.h +++ b/include/osmocom/bsc/handover_cfg.h @@ -268,6 +268,13 @@ static inline int bool2i(bool arg) "Time to suspend re-assignment after an lchan was re-assigned because of low RxQual\n" \ "Seconds\n") \ \ + HO_CFG_ONE_MEMBER(int, hodec2_penalty_low_rxqual_ho, 60, \ + "handover2 ", "penalty-time low-rxqual-ho", "<0-99999>", atoi, "%d", as_is, \ + HO_CFG_STR_HANDOVER2 \ + HO_CFG_STR_PENALTY_TIME \ + "Time to suspend handover back to a cell after bad RxQual caused handover away from it\n" \ + "Seconds\n") \ + \ HO_CFG_ONE_MEMBER(int, hodec2_retries, 0, \ "handover2 ", "retries", "<0-9>", atoi, "%d", as_is, \ HO_CFG_STR_HANDOVER2 \ diff --git a/src/osmo-bsc/handover_decision_2.c b/src/osmo-bsc/handover_decision_2.c index 14bc2d4b0..8627910e8 100644 --- a/src/osmo-bsc/handover_decision_2.c +++ b/src/osmo-bsc/handover_decision_2.c @@ -914,6 +914,19 @@ static int trigger_local_ho_or_as(struct ho_candidate *c, uint8_t requirements) full_rate ? "TCH/F" : "TCH/H", ho_reason_name(global_ho_reason)); handover_request(&req); + + /* Apply penalty timer hodec2_penalty_low_rxqual_ho */ + if (global_ho_reason == HO_REASON_INTERFERENCE + || global_ho_reason == HO_REASON_BAD_QUALITY) { + struct gsm0808_cell_id bts_id; + struct gsm_subscriber_connection *conn = c->current.lchan->conn; + int timeout = ho_get_hodec2_penalty_low_rxqual_ho(c->current.bts->ho); + gsm_bts_cell_id(&bts_id, c->current.bts); + LOGPHOCAND(c, LOGL_DEBUG, "Applying penalty-time low-rxqual-ho %d s on bts %u (%s), reason: %s\n", + timeout, c->current.bts->nr, gsm0808_cell_id_name_c(OTC_SELECT, &bts_id), + ho_reason_name(global_ho_reason)); + penalty_timers_add(conn, &conn->hodec2.penalty_timers, &bts_id, timeout); + } } return 0; } diff --git a/tests/handover/test_rxqual.ho_vty b/tests/handover/test_rxqual.ho_vty index f64de525d..6f86cf47f 100644 --- a/tests/handover/test_rxqual.ho_vty +++ b/tests/handover/test_rxqual.ho_vty @@ -10,6 +10,10 @@ # See Performance Enhancements in a Frequency Hopping GSM Network (Nielsen Wigard 2002), Chapter # 2.1.1, "Interference" in the list of triggers on p.157. +# first show undesired oscillation when penalty-time low-rxqual-ho is disabled +network + handover2 penalty-time low-rxqual-ho 0 + create-n-bts 2 set-ts-use trx 0 0 states * TCH/F - - - - - - meas-rep repeat 9 lchan 0 0 1 0 rxlev 40 rxqual 6 ta 0 neighbors 30 @@ -20,10 +24,26 @@ expect-ts-use trx 0 0 states * - - - - - - - expect-ts-use trx 1 0 states * TCH/F - - - - - - # Now the channel is on bts 1, which has lower rxlev than bts 0. -# The result is an undesired ho oscillation +# The result is an undesired ho oscillation, because the penalty timer is zero meas-rep lchan 1 0 1 0 rxlev 30 rxqual 0 ta 0 neighbors 40 expect-ho from lchan 1 0 1 0 to lchan 0 0 1 0 + +# Set a proper penalty timeout and report bad-rxqual again +network + handover2 penalty-time low-rxqual-ho 10 meas-rep repeat 10 lchan 0 0 1 0 rxlev 40 rxqual 6 ta 0 neighbors 30 expect-ho from lchan 0 0 1 0 to lchan 1 0 1 0 + +# This time the penalty timer prevents oscillation +meas-rep repeat 10 lchan 1 0 1 0 rxlev 30 rxqual 0 ta 0 neighbors 40 +expect-no-chan + +# After the penalty timeout passes, we do go back to the cell with stronger rxlev +wait 10 meas-rep lchan 1 0 1 0 rxlev 30 rxqual 0 ta 0 neighbors 40 expect-ho from lchan 1 0 1 0 to lchan 0 0 1 0 +# If the rxqual is still bad here after the penalty timeout, well, then we quickly snap back to the weaker cell, once +meas-rep repeat 10 lchan 0 0 1 0 rxlev 40 rxqual 6 ta 0 neighbors 30 +expect-ho from lchan 0 0 1 0 to lchan 1 0 1 0 +meas-rep repeat 10 lchan 1 0 1 0 rxlev 30 rxqual 0 ta 0 neighbors 40 +expect-no-chan diff --git a/tests/handover_cfg.vty b/tests/handover_cfg.vty index eb3ec3ed7..fb3c73c49 100644 --- a/tests/handover_cfg.vty +++ b/tests/handover_cfg.vty @@ -190,6 +190,7 @@ OsmoBSC(config-net)# list handover2 penalty-time failed-ho (<0-99999>|default) handover2 penalty-time failed-assignment (<0-99999>|default) handover2 penalty-time low-rxqual-assignment (<0-99999>|default) + handover2 penalty-time low-rxqual-ho (<0-99999>|default) handover2 retries (<0-9>|default) handover2 congestion-check (disabled|<1-999>|now) ... @@ -389,6 +390,7 @@ OsmoBSC(config-net)# handover2 penalty-time ? failed-ho Time to suspend handover for a subscriber after a failed handover into this cell; see also 'handover2 retries' failed-assignment Time to suspend handover for a subscriber after a failed re-assignment within this cell; see also 'handover2 retries' low-rxqual-assignment Time to suspend re-assignment after an lchan was re-assigned because of low RxQual + low-rxqual-ho Time to suspend handover back to a cell after bad RxQual caused handover away from it OsmoBSC(config-net)# handover2 penalty-time max-distance ? <0-99999> Seconds @@ -613,6 +615,7 @@ OsmoBSC(config-net-bts)# handover2 penalty-time ? failed-ho Time to suspend handover for a subscriber after a failed handover into this cell; see also 'handover2 retries' failed-assignment Time to suspend handover for a subscriber after a failed re-assignment within this cell; see also 'handover2 retries' low-rxqual-assignment Time to suspend re-assignment after an lchan was re-assigned because of low RxQual + low-rxqual-ho Time to suspend handover back to a cell after bad RxQual caused handover away from it OsmoBSC(config-net-bts)# handover2 penalty-time max-distance ? <0-99999> Seconds |