Initiation ●
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Switches (on/off) –
SCHO – SDCCH handover
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ASSOC - assignment to other cell
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IHO – intra-cell handovers
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IHOSICH - Intra-cell handover on signalling channel
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IBHOASS - Inter BSC handover during assignment
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IBHOSICH - Inter BSC handover on signalling channel
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FASTMSREG – fast moving MS
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COEXUMTS – switch for IRAT (on/off, BSC)
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SBHOACTIVE – is handover with usage of Service Indicator allowed
Timers –
TINIT – inhibits handovers, until it expires
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TURGEN – inhibits handovers, until it expires, when in urgency
Measurements ●
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RXLEV - signal strength measurement reports as integer values from 0 to 63, corresponds to signal strength of -110 dBm to -47 dBm. ENHANCED MEASUREMENT REPORT - element SCALE is an offset which might add +10 dB to the downlink signal strength resulting in -100 dBm to -37 dBm. RXQUAL - integer value between 0 and 7, where 0 corresponds to good quality (low BER) and 7 to bad quality (high BER) With EMR – MEAN_BEP have a higher granularity, integer value between 0 and 31. The locating algorithm transforms these values to a 0 to 76 scale. MISSNM – maximum number of missing reports, missing measurement reports are replaced by a linear interpolation
Compensations ●
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BSTXPWR - BSPWR –
BSPWR – output power for BCCH
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BSTXPWR – output power for other frequencies
BSTXPWR – PWR_USED –
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PWR_USED – power used when PC active
BSTXPWR(UL) – BSTXPWR (OL) –
when UL/OL structure
Filters ●
SSEVALSI – filter choice SDCCH
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SSEVALSD – filter choice TCH
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SSLENSI and SSLENSD – filter length for filters [6-9]
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[1-5] General FIR Filters –
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straight average filters, with different windows (SACCH periods):2, 6 10, 14, 18
[6] Recursive Straight Average Filter –
As FIR, except for better computational efficiency (minimal load on the BSC)
Filters (2) ●
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[7]Recursive Exponential Filter –
recursive filter with filter coefficient dependent on SACCH periods
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rxlev = α rxlev + (1-α)(ss(t))
[8] Recursive 1st. Order Butterworth Filter –
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[9] Median Filter –
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rxlev = α rxlev + (1-α)(ss(t)+ss(t-1))/2 median value from the set last n measurements
Straight forward average filter for TA
Minimum access requirements ●
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Minimum Signal Strength Condition –
MSRXMIN threshold for downlink signal strength
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BSRXMIN threshold for an estimated uplink signal strength
Penalties –
handover failure - cell to which the handover failed, is punished
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bad quality urgency handover – cell which was abandoned is punished
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excessive timing advance urgency handover – cell which was abandoned, and co-sited ones, are punished
Location ranking ●
EVALTYPE – 1 or 3
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Ericsson 1 –
MSRXSUFF and BSRXSUFF thresholds - sufficient signal levels (to divide cells in K- and L- cells)
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transition hysteresis TRHYST and a transition offset TROFFSET - in cell-to-cell relation
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Signal strength evaluation (K-criterion) ●
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Path loss evaluation (L-criterion) ●
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offset KOFFSET and hysteresis KHYST offset LOFFSET and a hysteresis LHYST
Ericsson 3 –
HYSTSEP – when signal strength for serving cell is high or low
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OFFSET + LOHYST or HIHYST
High level impacting features ●
Fast return to WCDMA after call release
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Fast return to LTE after call release
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NC2 after LTE
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RATPRIO for cell
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HPRIO, HPRIOTHR, LPRIOTHR – hysteresis and thresholds for prioritised RATs
Decisions (priority) ●
Urgency - timing advance
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Intra-cell for BQ
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Urgency - bad quality
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RAT priority
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HCS
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OL/UL + Multiband
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Basic ranking
Urgency – Timing Advance ●
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Limits –
TALIM for normal cell
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TALIMXOL for extended cell (XRANGE =YES)
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MAXTA (to qualify)
Penalty –
value PSSTA, duration PTIMTA
Intra-cell ●
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FQSS is the quality vs. signal strength function –
SSOFFSETUL, SSOFFSETDL - are signal strength offset parameters
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QOFFSETUL, QOFFSETDL - are quality offset parameters
For AMR FR –
SSOFFSETULAFR, SSOFFSETDLAFR
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QOFFSETULAFR, QOFFSETDLAFR
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TINIT – inhibits handovers
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TMAXIHO – time when HO is considered consecutive
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MAXIHO – maximum number of consecutive HO
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TIHO – time when IC-HOs are inibited
Urgency – bad quality ●
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Quality limits –
QLIMUL, QLIMDL – non-AMR
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QLIMULAFR, QLIMDLAFR – AMR FR
It is not allowed to HO to worse cell –
BQOFFSET, BQOFFSETAFR applied to HYST, LHYST, KHYST
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compared with ranking difference (rank(n)-rank(s))
Penalty –
Penalty – value PSSBQ, duration PTIMBQ
Assignment to other cell ●
ASSOC - on or off
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AW - assignment to a worse cell (on/off).
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IBHOASS – assignment to other cell, inter-BSC (on/off) AWOFFSET - candidates for Assignment to Worse Cell must be stronger than current cell decreased by this offset CAND – possible candidate: –
AWN - not at normal handover.
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NHN - to better cell and at normal handover
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BOTH - at normal handover
High level impacting features ●
Fast return to WCDMA after call release
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Fast return to LTE after call release
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NC2 after LTE
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RATPRIO for cell
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HPRIO, HPRIOTHR, LPRIOTHR – hysteresis and thresholds for prioritised RATs
HCS ●
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BSC –
LAYER , PLAYER
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HCSBAND - defines the priority for group of layers
Cell –
LAYERTHR, PHCSTHR - signal strength threshold to rank cells in different layers
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LAYERHYST - hysteresis
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HCSBANDTHR - signal strength threshold for HCS band criterion
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MAXCELLSINLAYER, MAXDBDEVINLAYER - number of cells of same layer prioritized by HCS, and max deviation from best one
Load –
HCSTRAFDISSTATE - activate HCS traffic distribution
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HCSCHAVAILTIMER - time for checking of idle TCHs
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HCSOUT, HCSIN – limits for idle TCH to HO out or in
Fast moving ●
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FASTMSREG – on/off THO - minimum time that an MS shall remain on a higher layer cell NHO – number of inter-cell handovers within THO to consider MS fast moving
OL/UL structure ●
LOL - path loss threshold (OL)
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TAOL - timing advance threshold (OL)
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LOHYST, TAOLHYST – hysteresis for TA and PL
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DTCBSC – Distance to Cell Border switch (on/of)
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DTCBSCDTCB - distance (OL)
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DTCBHYST - hysteresis for distance
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NDIST – additional threshold if neighbour should be on the BA list NNCELLS - number of non-cosited neighbouring cells that must be within NDIST from DTCB + DTCBHYST of OL subcell to trigger a DTCB evaluation
OL/UL structure ●
LOL - path loss threshold (OL)
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TAOL - timing advance threshold (OL)
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LOHYST, TAOLHYST – hysteresis for TA and PL
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DTCBSC – Distance to Cell Border switch (on/of)
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DTCBSCDTCB - distance (OL)
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DTCBHYST - hysteresis for distance
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NDIST – additional threshold if neighbour should be on the BA list NNCELLS - number of non-cosited neighbouring cells that must be within NDIST from DTCB + DTCBHYST of OL subcell to trigger a DTCB evaluation
OL/UL Load Distribution ●
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SCLD – on/off switch SCLDTIMEINT - cycle time of the subcell load monitoring SCLDLUL, SCLDLOL - percentage of idle full rate capable TCHs in the UL/OL subcell to attempt load out, or accept load in SCLDSC - preferred subcell.
MultiBand Cells ●
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OL/UL as prerequisite FBCHALLOC - prioritise different frequency bands/subbands in respect to BSSH FBOFFS - difference in pathloss between the BCCH frequency band group and the non-BCCH frequency band group. SCALLOC - restrict GPRS to OL/UL or set preferences PDCHALLOC - non-hopping TCHs on BCCH frequency shall be selected as first choice
Cell Load Sharing ●
GPRSPRIO on-demand PDCHs shall be treated as idle or busy
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CLSLEVEL - percentage of idle TCHs – to HO out
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CLSACC - percentage of idle TCHs – for HO in
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HOCLSACC - incoming handover due to load sharing (on/off)
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RHYST - final hysteresis reduction
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CLSRAMP - interval for hysteresis to be ramped
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CLSTIMEINTERVAL- cycle time of the load monitoring.
GSM-WCDMA ●
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COEXUMTS – switch for IRAT (on/off, BSC) SBHOACTIVE – is handover with usage of Service Indicator allowed COEXUMTSLSH – allows rejection of incoming handovers from UTRAN due to load in GSM COEXUMTSTINT – interval for load checking QSI, QSC, QSCI – strategy for measurements in idle/active FDDQMIN - minimum quality of UTRAN cell FDDQOFF - offset between signal quality of UTRAN and GSM cells
GSM-WCDMA HO ●
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FDDMRR - # of measured neighbouring UTRAN cell in measurement reports ISHOLEV - traffic load threshold of the serving GSM cell to evaluate UMTS measurements MAXISHO - defines the maximum number of allowed handovers to trigger to UTRAN per second MRSL - defines a minimum threshold for the "quality" measure Ec/No for handovers to UTRAN. SPRIO - indicates if 3G cells may be searched when BSIC decoding is required
