List Of Formulae Used In Customised Scripts

= 6 Formulas related: Nbr of paging groups = 3-AG*MFR ;if combined control channel Nbr of paging groups = 9-AG*MFR ;if non-combined control channel Paging_Buffer_Size = free buffers max

LIST OF FORMULAE USED IN

CUSTOMISED SCRIPTS

1

1 FORMULAE USED IN D1 SCRIPT 6

1.1 BH 6

1.2 agchb – AGCH Blocking (blck_13) 6

1.3 rachl – RACH Loading (rach_4) 6

1.4 minpagbuffer – Minimum Paging buffer space (pgn_2) 6

1.5 shldt – SDCCH Holding time (trf_4) 7

1.6 asa – Avg SDCCH availability (ava_4) 7

1.7 bst – BH SDCCH Traffic (trf_11a) 7

1.8 ast – Avg SDCCH Traffic (trf_11a) 8

1.9 asmtc – SDCCH for MTC 8

1.10 asmoc – SDCCH for MOC 8

1.11 asl – SDCCH for Location Updates 8

1.12 asd – Avg SDCCH drop % (sdr_1) 8

1.13 asdrf – Avg SDCCH RF drop % 9

1.14 asdabis – Avg SDCCH abis drop 9

1.15 bsblk – BH SDCCH Blocking % (blck_5a) 9

1.16 thht – TCH Holding Time (trf_5) 9

1.17 ata – Average TCH Availability (ava_1d) 10

1.18 btt – BH TCH Traffic (trf_1) 10

1.19 att – Avg TCH Traffic (trf_1) 10

1.20 btblk – TCH Raw blocking % (blck_1) 10

1.21 btblk2 – TCH Call blocking % (blck_8d) 11

1.22 atd2 – Avg TCH drop % (dcr_4f) 11

1.23 atd – Avg TCH drop (dcr_4e) 12

1.24 atdtr – Avg TCH Tr drop 12

1.25 atdrf – Avg TCH RF drop 12

1.26 atdabis – avg TCH abis drop 13

1.27 atdaif – Avg A-i/f drop 13

1.28 atdlapd – avg TCH Lapd drop 13

1.29 acsf – Avg Call Setup Failure Rate (cssr_2) 13

1.30 dhatt1 – Total HO attempts (out + in) (ho_13a) 13

1.31 dhfail1 – Avg HO failure rate (hfr_1) 14

1.32 dhatt2 – Total HO attempts (out + Intra cell) (ho_13c) 14

1.33 dhpb – Avg PBGT HO % 15

1.34 dhdr – Avg DR HO % 15

1.35 dhumbr – Avg Umbrella HO % 15

1.36 dhuq – Avg HO% due to ULQ 15

2

1.37 dhul – avg HO% due to UL Level 15

1.38 dhui – Avg HO% due to UL Interference 15

1.39 dhdq – Avg HO% due to DL Quality 15

1.40 dhdl – Avg HO% due to DL Level 15

1.41 dhdi – Avg HO% due to DL Interference 16

1.42 Call Attempt – No of Call Attempts 16

1.43 tch db hold – Avg TCH Dualband holding time 16

1.44 tch sing hold – Avg TCH singleband holding time 16

1.45 tch db srv – Avg TCH dualband reservation 16

1.46 tch sing srv – Avg TCH singleband reservation 16

1.47 btd2sum – denominator of BH TCH drop 16

1.48 atd2sum – denominator of Avg TCH drop 16

1.49 btdsum – denominator of BH TCH drop 17

1.50 atdsum - denominator of Avg TCH drop 17

1.51 AVG_TCH_OUTGO - Avg successful TCH outgoing HO 17

1.52 BH_TCH_OUTGO – BH successful TCH outgoing HO 17

1.53 itf_1 – Avg interference band (itf_1) 17

1.54 ho_8 – MSC Controlled incoming HO (ho_8) 18

1.55 ho_9 – MSC Controlled outgoing HO (ho_9) 18

1.56 ho_10 – BSC Controlled incoming HO (ho_10) 18

1.57 ho_11 - MSC Controlled outgoing HO (ho_11) 18

1.58 hfr_4a – MSC Controlled incoming HO failure% 18

1.59 hfr_5a – MSC Controlled outgoing HO failure % 19

1.60 hfr_6a – BSC Controlled incoming HO failure % 19

1.61 hfr_7a – BSC Controlled outgoing HO failure % 19

2. FORMULAE USED IN Q1 SCRIPT 21

2.1 Ulstr – Avg UL signal strength 21

2.2 Dlstr – Avg DL signal strength 21

2.3 Mspwr – Avt MS transmit power 21

2.4 Dist – Avg MS-BS distance 21

3. FORMULAE USED IN TRX_Q1 SCRIPT 22

3.1 Trf- Call time per TRX (trf_32a) 22

3.2 Time – Call time per TRX 22

3.3 Itf – Avg Band of TCH interference (itf_4) 22

3

1 FORMULAE USED IN D1 SCRIPT

Gives the TCH busy hour during the day.

Use: A BSC sends to a BTS an immediate assignment or immediate assignment

rejected commands If the AG buffer in the BTS is full, it will respond with a delete indication Thus the ratio of delete indications to the sum of immediate assignment and immediate assignment rejected describes the AG blocking After receiving the delete indication message the BSC releases the SDCCH.

Formula:

100 * sum(del_ind_msg_rec)/ sum(imm_assgn_rej+imm_assgn_sent)

Counters from table(s):

p_nbsc_res_acc

Use: This PI indicates how high the RACH load is on average.

Experiences on use: If the value is to the order of tens of per cent there probably are access problems

and MS users get, more often than usual, 3 beeps when trying to start calls Probable reason is UL interference.

Formula:

avg(ave_rach_busy/res_acc_denom3)

100 * - %

avg(ave_rach_slot/res_acc_denom1)

Counters from table(s):

p_nbsc_res_access

Use: To have an idea of how close to problems the BTS has been.

Known problems: It is difficult to say when the problems start Even if the counter 3018 does not yet

show the 0 value, there may have been the situation in one or some of the buffers that the capacity has run out.

Formula:

avg(min_paging_buf)

Counters from table(s):

p_nbsc_res_access

Parameters related:

Number of Blocks for AGCH (AG): e.g = 2

Number of MultiFrames (MFR): e.g = 6

Formulas related:

Nbr of paging groups = (3-AG)*MFR ;if combined control channel

Nbr of paging groups = (9-AG)*MFR ;if non-combined control channel

Paging_Buffer_Size = free buffers (max 8) * Nbr of paging groups

Min Paging Buffer (counter 3018) = min(Paging_Buffer_Space)

= min(Paging_Buffer_Size/2)

4

Paging Buffer Space is sent by BTS in the CCH_Load_Ind message to a BSC every 30 s A BSC sends current paging load as Paging_Buffer_Size to a statistical unit The minimum value of this is recorded as counter 3018 If Min Paging Buffer (counter 3018) equals to zero, paging blocking has occurred.

Use: The holding time may change due to modification of the timers or perhaps

software This time is part of the call setup time.

Experiences on use: The counters get 0 values if the BTS is locked Typically values from 2 to 3 sec

but over 4 sec with satellite Abis.

Formula:

sum(ave_sdcch_hold_tim)

- sec

sum(res_av_denom16)*100

Counters from table(s):

p_nbsc_res_avail

Use: Indicates how big share of all SDCCH resources have been available for traffic.

Failures (downtime) of TRX containing SDCCH affect this KPI.

Known problems: Affected by locked TRX under unlocked BCF and BTS

Formula:

sum(ave_sdcch_sub/res_av_denom3)

100 * - %

sum(ave_sdcch_sub/res_av_denom3)+ sum(ave_non_avail_sdcch)

Counters from table(s):

p_nbsc_res_avail

Gives the SDCCH traffic in the busy hour of the SDCCH

Known problems: SDCCH seizures are too short to be counted using 20s sampling if traffic is low

(less than 0,5Erl)

Note: Gives same results as trf_11 Experiments showed that results match well with

trf_45.

Formula:

avg(ave_busy_sdcch / res_av_denom15)

Counters from table(s):

p_nbsc_res_avail

Same as bst but gives the average value over the day

Gives the percentage of SDCCH seized for mobile terminated calls

SDCCH for MTC = sum(succ_seiz_term)/(total SDCCH true seizures)

5

sum(succ_seiz_term)

=

succ_seiz_term + succ_seiz_orig + sdcch_call_re_est + sdcch_emerg_call +

sdcch_loc_upd + IMSI_detach_sdcch + succ_seiz_supplem_serv)

Counters from p_nbsc_res_access

Gives the percentage of SDCCH seized for mobile originated calls

SDCCH for MOC = sum(succ_seiz_orig)/ (total SDCCH true seizures),

sum(succ_seiz_orig)

=

(succ_seiz_term + succ_seiz_orig + sdcch_call_re_est + sdcch_emerg_call +

sdcch_loc_upd + IMSI_detach_sdcch + succ_seiz_supplem_serv)

Counters from p_nbsc_res_access

Gives the percentage of SDCCH seized for Location updates

SDCCH for LU = sum(sdcch_loc_upd)/(total SDCCH true seizures),

sum(sdcch_loc_upd)

=

(succ_seiz_term + succ_seiz_orig + sdcch_call_re_est + sdcch_emerg_call +

sdcch_loc_upd + IMSI_detach_sdcch + succ_seiz_supplem_serv)

Counters from p_nbsc_res_access

sum(sdcch_radio_fail + sdcch_rf_old_ho + sdcch_user_act+

sdcch_bcsu_reset + sdcch_netw_act + sdcch_abis_fail_old + sdcch_abis_fail_call + sdcch_bts_fail + sdcch_lapd_fail + sdcch_a_if_fail_call+ sdcch_a_if_fail_old)

avg_sdcch_drop = - * 100

sum(sdcch_assign+sdcch_ho_seiz)

Counter from p_nbsc_traffic table.

Problem:1.sdcch_abis_fail is included When ghost access, a SDCCh is allocated and cause sdcch_abis_fail failure, which will bring high drop rate in low traffic network

2.In sdcch failure counter, it is not possible to separate LU and call seizures.

sum(a.sdcch_radio_fail+a.sdcch_rf_old_ho)

avg_sdcch_drop_rf = - *100

6

sum(a.sdcch_assign+a.sdcch_ho_seiz)

a=p_nbsc_traffic

sum(a.sdcch_abis_fail_call+a.sdcch_abis_fail_old) avg_sdcch_drop_Abis = -*100 sum(a.sdcch_assign+a.sdcch_ho_seiz)

a=p_nbsc_traffic

Formula:

100 - csf_1a =

sum(SDCCH_busy_att-tch_seiz_due_sdcch_con)

100* - %

sum(SDCCH_seiz_att)

Counters from table(s):

p_nbsc_traffic

Use: The holding time may change due to modification of the timers or perhaps

software You can use this PI to follow the impact of the modifications.

Experiences on use: The counters get 0 values if the BTS is locked Value higly dependant on number

of handovers that again is network plan dependent.

Formula:

sum(ave_ftch_hold_tim)

- sec

sum(res_av_denom17)*100

Counters from table(s):

p_nbsc_res_avail

Use: Failures (downtime) of TRXs cause loss of TCH and affect this KPI

Known problems: 1) If TRXs are locked and BTSs and BCFs are unlocked, the TCHs appear as

unavailable This means that both system and user can affect this KPI and make

it less useful

Formula:

available TCH

100 * - %

all TCH (traffic and GPRS)

sum(ave_avail_TCH_sum/ave_avail_TCH_den

+ ave_GPRS_channels_sum/ave_GPRS_channels_den)

=100 * - %

sum(ave_avail_TCH_sum/ave_avail_TCH_den

+ ave_GPRS_channels_sum/ave_GPRS_channels_den+ave_non_avail_TCH)

Counters from table(s):

p_nbsc_res_avail

7

1.18 btt – BH TCH Traffic (trf_1)

Experiences on use: If counted over one hour, Erlang is shown Counting Erlangs over a longer period

requires that the Erlang values per hour are first counted and then averaged Formula:

sum(ave_busy_tch / res_av_denom14)

Counters from table(s):

p_nbsc_res_avail

Unit: Erlang hours if measurement period is 1 hour

Same as atd but gives average over the day

Experiences on use: Was earlier (before blck_8a ) widely used on the cell and the area level.

Known problems: This PI does not take Directed Retry into consideration Rather, it shows only raw

blocking including also HOs Blocked HOs are normally not so serious because there are alternatives to go to Blocked new calls can be lost calls if Directed Retry is not in use.

Formula:

sum(tch_req_rej_lack)

100* - %

sum(tch_request)

Counters from table(s):

p_nbsc_traffic

Use: Applicable on area or BTS level.

Queuing and Directed Retry are the BSS features that can reduce blocking.

It is the failed call attempts that the MS user will notice, caused by the lack of

radio resources It is therefore one of the most critical KPIs.

On the cell level may appear in the busiest cells The cell needs an urgent capacity extension or has lost part of capacity due to a fault MS user usually hears three beep tones when call is rejected due to blocking.

Experiences on use: On the cell level, for example, 2 % blocking on Busy Hour has been used as a

criterion for design This KPI can be followed statistically e.g as nbr of cells in which the value exceeds the given threshold.

Known problems: 1) NOTE: If Trunk Reservation is used then HO and Call blocking can not be

counted precisely (there is only one counter for Trunk Res Invocation Refused case)

2) If dadlb_start_due_exeed_load is triggered and the dadlb handover fails the tch_call_req will be triggered twice This problem will be corrected in S10.

100-csf_3l =

sum(a.tch_call_req-a.tch_norm_seiz)

- sum(b.msc_o_sdcch_tch+ b.bsc_o_sdcch_tch+b.cell_sdcch_tch); DR calls

+ sum(a.tch_succ_seiz_for_dir_acc) ;ref.2

- sum(a.tch_rej_due_req_ch_a_if_crc ; Aif type mismatch or congestion

-(b.bsc_i_unsucc_a_int_circ_type ; Aif circuit pool handover failures

+b.msc_controlled_in_ho

+b.ho_unsucc_a_int_circ_type))

100-100* - %

8

sum(a.tch_call_req)

- sum(a.tch_rej_due_req_ch_a_if_crc ; Aif type mismatch or congestion

-(b.bsc_i_unsucc_a_int_circ_type ; Aif circuit pool handover failures

+b.msc_controlled_in_ho

+b.ho_unsucc_a_int_circ_type))

Counters from table(s):

a = p_nbsc_traffic

b = p_nbsc_handover

Ref.2 Compensation needed since in case of Direct Access to super reuse TRX

the tch_norm_seiz is triggered in parallel with the cell_sdcch_tch

Use: On the BTS level To rank cells by the share of TCH drop call failures per TCH

seizure (normal or HO) Intra-cell HO is excluded, which is meaningful in the case of IUO Inter-cell HOs are counted only as a netto value.

Known problems: See dcr_3g

Formula:

sum(a.tch_radio_fail+a.tch_rf_old_ho+a.tch_abis_fail_call+

a.tch_abis_fail_old+a.tch_a_if_fail_call+ a.tch_a_if_fail_old+

a.tch_tr_fail+ a.tch_tr_fail_old+a.tch_lapd_fail+ a.tch_bts_fail+

a.tch_user_act+ a.tch_bcsu_reset+a.tch_netw_act+a.tch_act_fail_call)

100* - %

sum(a.tch_norm_seiz) ;(normal calls)

+ sum(c.msc_i_sdcch_tch+c.bsc_i_sdcch_tch+c.cell_sdcch_tch) ;(DR calls)

- sum(a.succ_tch_seiz_for_dir_acc) ;ref.2

+ sum(a.tch_seiz_due_sdcch_con) ; (FACCH call setup calls)

+ sum(c.msc_i_tch_tch+c.bsc.bsc_i_tch_tch)

- sum(c.msc_o_tch_tch

+c.bsc.bsc_o_tch_tch) ;(TCH-TCH Ho netto in from other cells)

Counters from table(s):

a = p_nbsc_traffic

c = p_nbsc_ho

Ref.2 Compensation needed since in case of Direct Access to super reuse TRX the

tch_norm_seiz is triggered in parallel with cell_sdcch_tch.

Use: On the BTS level To rank cells by the share of TCH drop call failures per TCH

seizure (normal or HO) Intra-cell HO is excluded, which is meaningful in the case of IUO, for example.

Known problems: See dcr_3g

Formula:

100-csf_4y=

sum(a.tch_radio_fail+a.tch_rf_old_ho+a.tch_abis_fail_call+

a.tch_abis_fail_old+a.tch_a_if_fail_call+ a.tch_a_if_fail_old+

a.tch_tr_fail+ a.tch_tr_fail_old+a.tch_lapd_fail+ a.tch_bts_fail+

a.tch_user_act+ a.tch_bcsu_reset+a.tch_netw_act+a.tch_act_fail_call)

100* - %

sum(a.tch_norm_seiz) ;(normal calls)

+ sum(c.msc_i_sdcch_tch+c.bsc_i_sdcch_tch+c.cell_sdcch_tch) ;(DR calls)

- sum(a.tch_succ_seiz_for_dir_acc) ;ref.2

+ sum(a.tch_seiz_due_sdcch_con) ; (FACCH call setup calls)

+ sum(c.msc_i_tch_tch+c.bsc.bsc_i_tch_tch) ;(TCH-TCH Ho from other cells)

Counters from table(s):

a = p_nbsc_traffic

c = p_nbsc_ho

Ref.2 Compensation needed since in case of Direct Access to super reuse TRX the tch_norm_seiz is triggered in parallel with cell_sdcch_tch.

9

1.24 atdtr – Avg TCH Tr drop

sum(a.tch_tr_fail+ a.tch_tr_fail_old)

100* - %

sum(a.tch_norm_seiz) ;(normal calls)

+ sum(c.msc_i_sdcch_tch+c.bsc_i_sdcch_tch+c.cell_sdcch_tch) ;(DR calls)

- sum(a.succ_tch_seiz_for_dir_acc) ;ref.2

+ sum(a.tch_seiz_due_sdcch_con) ; (FACCH call setup calls)

+ sum(c.msc_i_tch_tch+c.bsc.bsc_i_tch_tch)

- sum(c.msc_o_tch_tch

+c.bsc.bsc_o_tch_tch) ;(TCH-TCH Ho netto in from other cells)

Counters from table(s):

a = p_nbsc_traffic

c = p_nbsc_ho

sum(a.tch_radio_fail+a.tch_rf_old_ho)

100* - %

sum(a.tch_norm_seiz) ;(normal calls)

+ sum(c.msc_i_sdcch_tch+c.bsc_i_sdcch_tch+c.cell_sdcch_tch) ;(DR calls)

- sum(a.succ_tch_seiz_for_dir_acc) ;ref.2

+ sum(a.tch_seiz_due_sdcch_con) ; (FACCH call setup calls)

+ sum(c.msc_i_tch_tch+c.bsc.bsc_i_tch_tch)

- sum(c.msc_o_tch_tch

+c.bsc.bsc_o_tch_tch) ;(TCH-TCH Ho netto in from other cells)

sum(a.tch_abis_fail_call+ a.tch_abis_fail_old)

100* - %

sum(a.tch_norm_seiz) ;(normal calls)

+ sum(c.msc_i_sdcch_tch+c.bsc_i_sdcch_tch+c.cell_sdcch_tch) ;(DR calls)

- sum(a.succ_tch_seiz_for_dir_acc) ;ref.2

+ sum(a.tch_seiz_due_sdcch_con) ; (FACCH call setup calls)

+ sum(c.msc_i_tch_tch+c.bsc.bsc_i_tch_tch)

- sum(c.msc_o_tch_tch

+c.bsc.bsc_o_tch_tch) ;(TCH-TCH Ho netto in from other cells)

sum(a.tch_a_if_fail_call+ a.tch_a_if_fail_old)

100* - %

sum(a.tch_norm_seiz) ;(normal calls)

+ sum(c.msc_i_sdcch_tch+c.bsc_i_sdcch_tch+c.cell_sdcch_tch) ;(DR calls)

- sum(a.succ_tch_seiz_for_dir_acc) ;ref.2

+ sum(a.tch_seiz_due_sdcch_con) ; (FACCH call setup calls)

+ sum(c.msc_i_tch_tch+c.bsc.bsc_i_tch_tch)

- sum(c.msc_o_tch_tch

+c.bsc.bsc_o_tch_tch) ;(TCH-TCH Ho netto in from other cells)

sum(a.tch_lapd_fail)

100* - %

sum(a.tch_norm_seiz) ;(normal calls)

+ sum(c.msc_i_sdcch_tch+c.bsc_i_sdcch_tch+c.cell_sdcch_tch) ;(DR calls)

- sum(a.succ_tch_seiz_for_dir_acc) ;ref.2

+ sum(a.tch_seiz_due_sdcch_con) ; (FACCH call setup calls)

+ sum(c.msc_i_tch_tch+c.bsc.bsc_i_tch_tch)

- sum(c.msc_o_tch_tch

+c.bsc.bsc_o_tch_tch) ;(TCH-TCH Ho netto in from other cells)

10