Downlink Dual CarrierLink adaptation
Feature interworking
New parameters
Dimensioning (PCU2-E)
Single carrier allocations in Downlink and Uplink
Up to 5 TSLs in DL - max MS Multislot Class capability supported by
PCU2 (Class 40-45)
Up to 296 kbps (5TSLs @ MCS9) of theoretical peak RLC/MAC
throughput
Up to BSS13
Dual Carrier in Downlink - part of 3GPP Rel.7 GERAN Evolution
BSS14
increased flexibility of TSL allocation
more efficient sharing of the system throughput
Higher number of TLSs allocated for DL TBFs
up to 10 TSLs in DL
Improved user data throughput and reduced user perceived
delay
up to 592 kbps (10TSLs @ MCS9) of theoretical peak RLC/MAC
throughput
c1
c1
c2
Introduction
With Downlink Dual Carrier (DLDC) resources of an EGPRS downlink
TBF can be assigned to a mobile station on two TRXs.
DLDC introduces new (EGPRS) multislot capabilities, and a new MS
hardware is required. A DLDC capable MS has one
transmitter-receiver with two receivers (Rel. 7 terminal
required).
DLDC enables higher data rates through usage of higher timeslot
quantity, DLDC doubles the timeslot quantity. For example a
multislot class 30 MS is capable up to 10 downlink timeslots, five
on each carrier, that is 5+5 dual carrier configuration.
DLDC feature is licensed feature with TRX capacity license. DLDC is
application software.
Maximum number of slots in DL
Maximum throughput at MSC9 [kbps]
Single carrier mode
Dual carrier mode
Single carrier mode
Dual carrier mode
6
12
355
710
MS has to indicate its Dual Carrier capability
Multislot Capability Reduction for Downlink Dual Carrier field in
MS Radio Access Capability IE (3GPP TS 24.008)
the presence of this field means that MS supports DLDC while the
absence means the opposite
this field determines the MS Multislot Capability for Dual Carrier
mode
Particular signaling messages have been modified in order to
support DLDC feature (3GPP TS 44.060), e.g.:
Packet Downlink Assignment and Packet Timeslot Reconfigure have
been extended with new Information Elements describing the
resources for both carriers, e.g.:
Assignment Type (dual or single carrier)
Frequency Parameters C1(C2) or Dual Carrier Frequency
Parameters
Timeslot Allocation C1(C2)
EGPRS Packet Downlink ACK/NACK – two separate EGPRS Channel Quality
Report IEs for both assigned carriers (EGPRS Channel Quality Report
and Secondary Dual Carrier Channel Report)
Presentation / Author
If an MS erroneously indicates DLDC-capability but no EGPRS
multislot class, PCU treats the MS as a non-DLDC-capable MS.
PCU ignores the 'Downlink Dual Carrier for DTM Capability' field of
the MS Radio Capability IE, and it never allocates DLDC resources
for an MS in dual transfer mode
* © Nokia Siemens Networks
Downlink Dual Carrier
MS Multislot Class (3GPP TS 45.002)
the maximum number of DL TSLs (Rx) is applicable to each carrier
separately
the maximum aggregated (over both carriers) number of DL TSLs must
not exceed 2*Rx
the sum of UL TSLs and TSLs on any DL carrier must not be greater
than value of ‘Sum’
Multislot Capability Reduction for Downlink Dual Carrier
based on the indicated MSCR the maximum number of DL TSL is
determined according to the following table
Table 1 Multislot capabilities for particular MS classes
Table 2 Maximum number of DL TSL for Dual Carrier allocations
supported by PCU2
Multislot Class
Maximum number of DL TSL per one carrier
Maximum number of DL TSLs for Dual Carrier for different values of
the ‘Multislot Capability Reduction for Downlink Dual
Carrier’
0
1
2
3
4
5-7
5
10
9
8
7
6
6
4
8
8
8
7
6
6
5
10
10
10
9
8
7
Presentation / Author
The maximum number of DL slots supported by PCU /BSS20084/ differs
from that defined for the multislot class in /45002/, the multislot
capability reduction is subtracted from the maximum aggregate
number of slots as given in the standard, and the reduction affects
timeslot allocation only when the result is less than the maximum
aggregate number defined in Table 1: e.g. in case of multislot
class 35 — for which the standard allows five DL slots per carrier
and an aggregate of ten over two carriers, while PCU supports four
and eight slots, respectively — the multislot capability reduction
is subtracted from the standardised ten aggregate slots, and
therefore a reduction of less than three slots does not affect the
maximum number of DL slots PCU may allocate.
‘Multislot Capability Reduction for Downlink Dual Carrier’ field
value 7 is reserved for future use, but in case PCU erroneously
receives value 7, it handles the MS as if the reduction indicated
were 6.
* © Nokia Siemens Networks
Downlink Dual Carrier
Table 4 Exemplary DC MS configurations for Multislot Classes
30-33
Table 1 Multislot capabilities for exemplary MS classes
Table 2 Maximum number of DL TSL for Dual Carrier allocations
supported by PCU2
MS indicating High Multislot Class 30 and MSCR=2 is to be assigned
resources in DLDC mode
At max 8 DL TSLs in total (on both carriers) may be assigned and 1
TSL in UL
Multislot Class
Maximum number of DL TSL per one carrier
Maximum number of DL TSLs for Dual Carrier for different values of
the ‘Multislot Capability Reduction for Downlink Dual
Carrier’
0
1
2
3
4
5-7
5
10
9
8
7
6
6
4
8
8
8
7
6
6
5
10
10
10
9
8
7
TRX selection
Determination of the Rx/Tx-window size
the number of TSLs to be allocated to TBF(s)
Determination of DLDC allocation candidates
all configurations which could be assigned to MS considering
current resources availability
Selection of the highest-capacity DLDC allocation
Selection of the highest-capacity SC allocation
Final allocation selection
the best one of the previously determined DLDC and SC
allocations
ready
Single Carrier allocation selection (capacity criterion)
Final allocation selection (SC and DC comparison)
start
DLDC Channel Allocation – BTS selection
In BTS selection algorithm for a DLDC MS both the best SC and the
best DLDC BTS capacities are calculated
DLDC BTS capacity is calculated as the maximum sum of capacities
offered by a pair of TRXs which can be used for DLDC resource
allocation
TRX capacity is calculated taking into account GPRS territory size,
load resulting from ongoing TBFs and MS Multislot
capabilities
BTS offering the highest capacity is selected whether this capacity
is SC or DLDC
among BTSs providing the same capacity the one with lager GPRS
territory is selected
If the highest capacity calculated for the selected BTS was DLDC,
the pair of TRXs providing the best DLDC capacity is identified in
the BTS selection output
additionally the TRX providing the best SC resources is identified
- the TRX providing the best SC capacity may not be one of the DLDC
TRXs
If the BTS has been chosen due to its higher SC capacity, only SC
resources are looked for in channel allocation procedure – DLDC
channel allocation is not proceeded
ready
Single Carrier allocation selection (capacity criterion)
Final allocation selection (SC and DC comparison)
start
Presentation / Author
BTS selection in a segment is done when a new TBF is created or the
existing TBF is getting reallocated.
Calculation of the best DLDC BTS capacity is followed by the
calculation of the best single carrier BTS capacity, which is
carried out as required for S13. For DLDC activated BTSs, both the
best DLDC and the best single carrier capacities are therefore
calculated; for BTSs which are not DLDC activated, only the best
single carrier capacity is calculated. When BTS is being selected
for a non-concurrent TBF, the better of the calculated DLDC and
single carrier capacities is kept for comparison with other BTSs;
in concurrent cases, the best DL and UL capacities are first
selected from the respective DLDC and single carrier
configurations, and then the lower of these two capacities is kept
for comparison with other BTSs.
When the highest capacity calculated for the selected BTS was
single carrier, when BTS is selected for a non-concurrent UL TBF or
when resources are being allocated from the extended or super
extended coverage areas of an extended cell, no TRXs are identified
in the BTS selection output
Furthermore, when a DL TBF is being created for a DLDC-capable MS,
PCU carries out BTS selection also when it holds existing resources
for the MS provided that these resources are only in UL and they
are allocated from a BTS which is not DLDC activated.
DLDC Channel Allocation is proceeded only if the selected BTS was
chosen on the basis of its max DLDC capacity
* © Nokia Siemens Networks
Downlink Dual Carrier
DLDC Channel Allocation – TRX selection
In case the resource (re)allocation does not involve BTS selection,
the pair of TRXs providing the best DLDC capacity and the TRX
offering the best SC capacity are selected within the current
BTS
TRXs capacity is calculated as the sum of capacities offered by all
TSLs which can be assigned to a TBF (GPRS territory size and MS
Multislot capabilities)
TSL capacity is calculated taking into account load resulting from
ongoing TBFs
Only a pair of TRXs with the best DLDC capacity and a TRX providing
the best SC capacity are used in further phase of DLDC channel
allocation procedure
ready
Single Carrier allocation selection (capacity criterion)
Final allocation selection (SC and DC comparison)
start
DLDC Channel Allocation – Rx/Tx-window
Rx/Tx-window is a set of DL/UL contiguous TSLs determined based on
MS Multislot Capabilities
Either PS territory size or the MSCR do not affect the size of the
Rx/Tx-window
these two factors are taken into account in the further phase of
channel allocation procedure
In case of concurrent (UL+DL) TBFs the distribution of TSLs between
the Rx- and Tx-windows is determined according to the
CONC_UL_TBF_FAVOR_DIR and CONC_DL_TBF_FAVOR_DIR parameters (PRFILE)
and the observed UL and DL data transfer intensities
For DLDC allocations the Rx-window size is the same and it
comprises the same timeslots on both carriers
For DLDC concurrent allocations Tx-window is limited to 2 TSLs
since Extended Dynamic Allocation (EDA) is not supported with
DLDC
Example: MS of Multislot Class 33 indicating MSCR=0
for non-concurrent DLDC allocation the Rx-window equals 5
TSLs
for concurrent DL favored allocation Rx-window equals 5 TSLs while
Tx-window comprises 1 TSLs
for concurrent UL favored non-EDA allocation Rx-window equals 4
TSLs while Tx-window comprises 2 TSLs
ready
Single Carrier allocation selection (capacity criterion)
Final allocation selection (SC and DC comparison)
start
Presentation / Author
In case of non-EDA UL TBF the concurrent DLDC TBF establishment may
trigger the re-allocation of the UL resources – the preference is
given to DLDC configuration
* © Nokia Siemens Networks
Downlink Dual Carrier
DLDC Channel Allocation – DLDC allocation candidates (1)
Rx-window (together with Tx-window) is slid over the pair of the
selected TRXs and for each position DLDC allocation candidate is
determined
for each Rx-window position PCU allocates on both carriers the
maximum possible number of TSLs within the Rx-window
all the available PS TSLs covered by the Rx-window are selected as
a DLDC allocation candidate
Different amount of TSLs and different TSL numbers may be allocated
on different TRXs
If MS indicates MSCR different than zero, the number of DL TSLs in
Rx-window is limited according to table 2 or table 3
PCU excludes TSLs one-by-one selecting the TSL which is closest to
the CS/PS territory border
PS TSLs of the DLDC allocation candidate which cannot serve more
TBFs due to multiplexing limits (determined by two attributes
pcuMaxNoULtbfInCH and pcuMaxNoDLtbfInCH) are excluded
ready
Single Carrier allocation selection (capacity criterion)
Final allocation selection (SC and DC comparison)
start
Presentation / Author
When DLDC resources are searched, the Rx window is of equal size on
both carriers and it comprises the same timeslots on both carriers
but during selection of TSLs configuration different number of TSLs
and different TSL numbers on different TRXs are possible.
* © Nokia Siemens Networks
Downlink Dual Carrier
DLDC Channel Allocation – DLDC allocation candidates (2)
In case of concurrent allocation, if at either end of the Rx-window
there are TSLs which cannot be allocated on either TRX (e.g. TSLs
which are not part of the PS-territory), they may be shifted to the
opposite direction
the number of TSLs shifted from the Rx-window to the Tx-window must
not increase Tx-window to more than 2 TSLs (EDA is not supported
with DLDC)
if TSLs cannot be shifted the Rx/Tx-windows are reduced
UL TSLs cannot overlap DL allocation even if allocated on different
carriers
Multislot class physical restrictions defined in 3GPP TS 45.002
(TSLs required by an MS for switching between transmission,
reception and measurements) must be respected
Allocation candidates having TSLs on only one DL carrier are just
ignored
Exemplary DLDC allocation candidates for MS class 33: Rx-window=5
and Tx-window=1
Presentation / Author
if TSLs cannot be shifted the Rx/Tx-windows are reduced
this reduction is done only for the currently considered allocation
candidate
after shifting to the next position the Rx- and Tx- windows are
restored to the original sizes
* © Nokia Siemens Networks
Downlink Dual Carrier
DLDC Channel Allocation – DLDC allocation selection
Among all DLDC allocation candidates the one providing the highest
capacity is selected
The capacity offered by the TSLs of a DLDC allocation candidate is
calculated as a sum of the capacities of each timeslot included in
the DLDC allocation candidate
In case of concurrent TBFs, both UL and DL capacity are
considered
The allocation providing the best capacity is selected whether it
comprises the most TSLs or not
If more than one configuration yields the same capacity, the
configuration with the most TSLs is preferred
ready
Single Carrier allocation selection (capacity criterion)
Final allocation selection (SC and DC comparison)
start
DLDC Channel Allocation – Final allocation selection
Following DLDC allocation selection the best SC allocation is
searched on the TRX providing the best SC capacity within the
selected BTS
the highest-capacity SC allocation is then considered in the final
resource selection
The best DLDC allocation is compared with the best SC one and the
configuration providing higher capacity is finally chosen
if the capacity of DLDC and SC allocations is the same, the one
with higher number of TSLs is chosen
if the capacity and number of TSLs of DLDC and SC allocations are
the same, DLDC allocation is selected
in case of concurrent UL-favored EDA allocation the SC allocation
is selected
In case of non-concurrent DLDC TBF the carrier farther from the
PS/CS territory border is selected as carrier 1
In case of a concurrent TBFs, if UL resources are available on both
DLDC carriers, the carrier providing higher UL capacity is selected
as carrier 1
ready
Single Carrier allocation selection (capacity criterion)
Final allocation selection (SC and DC comparison)
start
Presentation / Author
In case the number of allocated TSLs is lower than the number
required in DLDC configuration a territory upgrade is
triggered
* © Nokia Siemens Networks
Downlink Dual Carrier
PS territory upgrades
For DLDC-capable MS having SC allocation the standard (legacy) PS
territory upgrade procedure is applied
the territory is extended so that the MS capability on one carrier
can be fulfilled
PCU does not indicate whether territory upgrade is requested for
DLDC-capable MS or non-DLDC-capable one
For DLDC TBF the PS territory upgrade may be requested if the
following conditions are fulfilled (all legacy criteria must be met
as well)
the number of allocated TSLs is less than the number of TSLs the MS
could use in DL (considering the Rx-window size and indicated
MSCR)
PS territory of the selected BTS includes TSLs on no more than 2
TRXs
the number of TSLs in the PS territory limited by the border
between the PS and CS territories is lower than minimum of
Rx-window and Max_MSCR – Rx-window
Max_MSCR is the maximum number of DL TSLs the MS could use on both
TRXs according to its multislot class and MSCR (tables 1, 2 and
3)
Example: MS Class 33 with MSCR=2 -> Rx-window=5, Max_MSCR=8;
number of TSLs on TRX-2 < Max_MSCR – Rx-window
Presentation / Author
In the downgrade procedure, BTS selection and Channel Allocation
algorithm may lead reallocation of TBF from Dual Carrier to Single
Carrier, Dual Carrier to Dual Carrier or Single Carrier to Dual
Carrier
* © Nokia Siemens Networks
In case of PS territory upgrade for DLDC TBF the number of
requested TSLs is the maximum of the following two numbers:
the number of TSLs needed to reduce the average number of TBFs per
PDCH to the value defined by PRFILE parameter
PR_NR_T_PSW_UPGRADE_TAR_TBF_NB
the number of TSLs necessary to increase the number of PS territory
TSLs to the value of min(Rx-window, Max_MSCR – Rx-window)
Example: the PS/CS territory border limits the PS territory on
TRX-2 to 2 TSLs
MS Class 33 with MSCR=0 -> Rx-window=5, Max_MSCR=10, Max_MSCR –
Rx=5 -> upgrade of 3 TSLs is requested (not considering the
average TBFs per TSL rule)
MS Class 33 with MSCR=2 -> Rx-window=5, Max_MSCR=8, Max_MSCR –
Rx=3 -> upgrade of 1 TSLs is requested (not considering the
average TBFs per TSL rule)
Downlink Dual Carrier
PS territory upgrades
Presentation / Author
These territory upgrade rules apply both for initial TBF creation
and for TBF reallocations
PRFILE parameter PR_NR_T_PSW_UPGRADE_TAR_TBF_NB (default 1.0 TBFs
per TSL)
* © Nokia Siemens Networks
Downlink Dual Carrier
Link Adaptation
With DLDC a single TBF is split on two independent carriers
there are no constraints on the two carriers paired in DC mode -
they may have very different frequency reuses and different hopping
laws (it is possible that only one of them performs FH)
One common Link Adaptation instance is applied to both
carriers
LA provides TBF (not carrier) specific MCS variables (Commanded
MCS, Initial MCS and Max MCS for Retransmissions)
MCS to be applied is determined using the Commanded MCS, Initial
MCS and Max MCS for Retransmissions variables as in the current
implementation
In case of higher asymmetry (e.g.: MCS-9 vs. MCS-5) MS would even
experience throughput degradation after switching to DC mode;
however, in case of lower asymmetry (e.g.: MCS-9 vs. MCS-7) MS
would experience the throughput gain even with common LA
Presentation / Author
The EGPRS PACKET DOWNLINK ACK/NACK message may contain two channel
quality reports, namely EGPRS Channel Quality Report IE and
Secondary Dual Carrier Channel Report IE. The EGPRS PACKET DOWNLINK
ACK/NACK message may contain only one channel quality report and it
can be either EGPRS Channel Quality Report IE or Secondary Dual
Carrier Channel Report IE. The EGPRS PACKET DOWNLINK ACK/NACK
message may be received without any channel quality reports.
If the DL DC configuration (TRX-x and TRX-y) is reallocated to DL
DC configuration (TRX-z and TRX-w) and if EPDAN message is received
during the reallocation, then it may happen that BEP values
measured on old resources (TRX-x and TRX-y) are fed into the LA
algorithm and the resulting MCS is then used on the new resources
(TRX-z and TRX-w). This is accepted.
If a DL DC configuration (TRX-x and TRX-y) is reallocated to single
carrier mode (TRX-z) and if EPDAN message is received during the
reallocation, then it may happen that the BEP measured on old
carrier-1 (TRX-x) is fed into the LA algorithm (the BEP measured on
old carrier-2 (TRX-y) is ignored) and the resulting MCS is then
used on the new resources (TRX-z). This is accepted.
If a TBF operating in single carrier mode (TRX-x) is reallocated to
dual carrier configuration (TRX-z and TRX-w) and if EPDAN message
is received during the reallocation, then it may happen that the
BEP measured on old resources (TRX-x) is fed into the LA algorithm
and the resulting MCS is then used on the new resources (TRX-z and
TRX-w). This is accepted.
When the channel quality measurements (C_VALUE, GMSK_MEAN_BEP
and/or 8PSK_MEAN_BEP) are used in other than LA purposes, then the
PCU shall aply the values received in the EGPRS Channel Quality
Report IE as in the existing implementation. The channel quality
measurements received in the Secondary Dual Carrier Channel Report
IE are used only for LA purposes.
* © Nokia Siemens Networks
Downlink Dual Carrier
EGPRS
EGPRS must be enabled if DLDC feature is wanted to be used.
No support of simultaneous DLDC and DTM
DLDC mode cannot be established if DLDC capable MS is having a DTM
connection
If for a (DLDC and DTM capable) MS being in DLDC mode a DTM request
is received, PCU releases the DLDC TBF and initiates the SC TBF
establishment
No support of simultaneous DLDC and Extended Dynamic
Allocation
DLDC mode cannot be established if DLDC capable MS is having a EDA
allocation
UL EDA TBF may be established only if DLDC-capable MS is not in
DLDC mode
When an UL-favored concurrent TBF allocation leads to an UL EDA TBF
allocation, an existing DLDC TBF needs to be reallocated as a SC
TBF
No support of DLDC in Extended Area and Super Extended Area
DLDC is always disabled for E- and S-TRXs
No support of Flexi EDGE Dual TRX Automatic Power Down
if DLDC is used the territory is not moved to another TRX in order
to be able to shut down TRXs
Presentation / Author
Possibility of activation cannot be guaranteed on PCU2-U/D, PCU2-E
itself will not restrict the possibility of activation.
DL TBF operating in DLDC configuration can be either in RLC ack
mode or in RLC unack mode
* © Nokia Siemens Networks
Downlink Dual Carrier
DLDC Enabled
object: BTS unit: - range: 0 (N) 1 (Y) step: 1 default: 0
This parameter determines the Downlink Dual Carrier feature status
(enabled/disabled) in the BTS Note: Setting this parameter to its
default value means that feature is disabled in the BTS. When
enabling the DLDC, the following pre-requirements are checked by
the system: DLDC license is in ON state and there is enough
capacity EGPRS is enabled in the cell (egprsEnabled=1) BTS is
served by PCU2 The following checking must be done by the operator:
BTS has 2 normal area TRXs which are EGPRS enabled
(gprsEnabledTrx=1) and belong to same EDAP and the same DSP Default
GPRS Capacity (defaultgprsCapacity) is configured in such a way
that the GPRS territory is split onto two TRXs; to fully exploit
supported MS multislot capabilities, PS territory should comprise
of at least 5 TSLs on each TRX. It is also recommended to enable
the High Multislot Class feature. After enabling/disabling the DLDC
the operator must trigger updating of the PCU (new MML command) in
order to get the PCU DSP resources reallocated. O&M updates to
RNW database the DLDC update info to value “update needed” in order
to tell the user that PCU must be updated.
Presentation / Author
* © Nokia Siemens Networks
Downlink Dual Carrier
PCU up to date
object: BTS unit: - range: Update needed Update done step: -
default: Update needed
DLDC update info for BTS object to tell operator whether DLDC
information is updated to PCU or not after DLDC modification. Only
system can modify this parameter. Note: This is not user adjustable
attribute – it’s rather kind of system indicator whether the PCU
update after DLDC feature activation should be done by the user or
not.
PUTD
PCU up to date
object: PCU unit: - range: Update needed Update done step: -
default: Update needed
DLDC update info for PCU object to tell operator whether DLDC
information is updated to PCU or not after DLDC modification. Only
system can modify this parameter. Note: This is not user adjustable
attribute – it’s rather kind of system indicator whether the PCU
update after DLDC feature activation should be done by the user or
not.
DOP
object: BSC unit: - range: 0..80 step: 1 default: 0
With this parameter operator can change the behavior of the PCU
selection algorithm in cases when DLDC is used and the pool
contains both PCU2-E and PCU2-D/U type cards. Note: The higher
value of this parameter the higher preference for PCU2-E (PCU2-E
cards are allowed to get higher load than other PCU2 types).
Presentation / Author
DLDC OFFSET FOR PCU2-E – is taken into account in PCU load
calculations. If the value for DLDC offset for PCU2-E
selection(DOP) parameter is different than 0 (meaning that PCU2-E
cards are then preferred for DLDC DAPs) it is allowed that PCU2-E
cards gets higher load than other PCU2 types.
BTS: With this parameter system informs user whether or not DLDC
information of the BTS is updated to PCU
PCU: With this parameter system informs user whether or not DLDC
information of all BTSs using this PCU is updated to PCU
Operator gives the new PCU update command which causes following
steps to be done by system:
Territories of the whole PCU are downgraded
EDAP table is updated
Territories of the whole PCU is upgraded so that DLDC enabled BTSs
are handled first
DLDC update infos are updated to “update done” value
* © Nokia Siemens Networks
Downlink Dual Carrier
BTS DLDC TSL BALANCE THRESHOLD
PRFILE parameter object: BSC unit: % range: 0..100 step: 1 default:
100
This parameter determines the threshold for triggering an intra-BTS
load reallocation for a DLDC-capable MS having single carrier DL
TBF when DLDC resources are available within the BTS. Note: The
DLDC intra-BTS reallocation may be triggered if three following
conditions are met MS does not have a concurrent EDA UL TBF DLDC is
activated in BTS average capacity of DL allocated TSLs ≤ average
capacity of all BTS DL PS TSLs*BTS_DLDC_TSL_BALANCE_THRESHLD Rule:
The lower the value of this attribute the more stringent condition
for DLDC intra-BTS reallocation. Setting this parameter to e.g. 50%
means that DLDC intra-BTS reallocation will be triggered if the
average capacity of DL allocated TSLs is twice lower than average
free capacity of all DL PDCHs in BTS.
Presentation / Author
REQ 9 TSL DL
This counter provides the number of requests for 9-TSL DL TBF
allocation or reallocation Trigger event: request for 9 TSLs for DL
TBF (re)allocation. Use case: calculations of the 9-TSL Allocations
Requests Ratio (REQ 9 TSL DL/REQ x TSL DL; x=1-12)
REQ 10 TSL DL
This counter provides the number of requests for 10-TSL DL TBF
allocation or reallocation Trigger event: request for 10 TSLs for
DL TBF (re)allocation. Use case: calculations of the 10-TSL
Allocations Requests Ratio (REQ 10 TSL DL/REQ x TSL DL;
x=1-12)
REQ 11 TSL DL
This counter provides the number of requests for 11-TSL DL TBF
allocation or reallocation Trigger event: request for 11 TSLs for
DL TBF (re)allocation. Use case: calculations of the 11-TSL
Allocations Requests Ratio (REQ11 TSL DL/REQ x TSL DL;
x=1-12)
REQ 12 TSL DL
This counter provides the number of requests for 12-TSL DL TBF
allocation or reallocation Trigger event: request for 12 TSLs for
DL TBF (re)allocation. Use case: calculations of the 12-TSL
Allocations Requests Ratio (REQ 12 TSL DL/REQ x TSL DL;
x=1-12)
These counters are updated regardless of the status of DLDC
feature. Counters for 1-8 TSL DL TBF allocations/reallocations have
been introduced in previous BSS releases
Presentation / Author
Updated When nine TSLs are requested for a TBF in DL
(re)allocation. The number of requested TSLs is determined based on
MS multislot class.
* © Nokia Siemens Networks
Downlink Dual Carrier
ALLOC 9 TSL DL
This counter provides the number of 9-TSL DL TBF allocations or
reallocations Trigger event: 9 TSLs for DL TBF has been
(re)allocated. Use case: calculations of the 9-TSL Allocations
Ratio (ALLOC 9 TSL DL/ALLOC x TSL DL; x=1-12) REMARK: counters for
1-8 TSL DL TBF allocations/reallocations have been introduced in
previous BSS releases
ALLOC 10 TSL DL
This counter provides the number of 10-TSL DL TBF allocations or
reallocations Trigger event: 10 TSLs for DL TBF has been
(re)allocated. Use case: calculations of the 10-TSL Allocations
Ratio (ALLOC 10 TSL DL/ALLOC x TSL DL; x=1-12) REMARK: counters for
1-8 TSL DL TBF allocations/reallocations have been introduced in
previous BSS releases
DL TSL REQUEST FOR DLDC CAPABLE MS
This counter provides the number of TSL allocation requests
(initial or reallocation) for DLDC Trigger event: updated
regardless of DLDC feature activation status upon receiving of the
DL TBF allocation request from DLDC capable MS Use case:
calculations of the Potential DLDC Users Ratio (DL TSL REQUESTS FOR
DLDC CAPABLE MS / REQ x TSL DL (x=1..12)) Note: This KPI may be
monitored before DLDC feature activation
Presentation / Author
Updated When nine TSLs are requested for a TBF in DL
(re)allocation
* © Nokia Siemens Networks
Downlink Dual Carrier
DLDC TSL REQUEST IN DLDC ENABLED CELL
This counter provides the number of TSL allocation requests
(initial or reallocation) for DLDC. Trigger event: Incremented by
one when allocation is requested by DLDC capable MS in a cell where
DLDC enabled BTS is available. Use case: calculations of the DLDC
TBF Allocation Success Ratio
DLDC TSL ALLOCATION CREATED
This counter provides the number of created DLDC TSL allocations
Trigger event: TSL allocation contains TSLs from two TRXs. Amount
of allocated TSLs may be equal or lower than amount of requested
TSLs. Use case: calculations of DLDC Allocation Success Ratio (DLDC
TSL ALLOCATION CREATED / DLDC TSL REQUEST IN DLDC ENABLED
CELL)
DLDC ATTEMPT FAILED DUE TERRITORY
This counter provides the number of failed DLDC allocation requests
due to lacking DLDC territory in DLDC enabled BTS Trigger event:
two TRXs of the DLDC BTS are not in one EDAP or not handled by the
same DSP in PCU or there are no free resources in PS territory, and
as a result a single carrier allocation is performed. Use case:
calculations of the Ratio of DLDC Allocation Failures due to No
Territory (DLDC ATTEMPT FAILED DUE TERRITORY/ DLDC TSL REQUEST IN
DLDC ENABLED CELL)
Presentation / Author
Updated When nine TSLs are requested for a TBF in DL
(re)allocation
* © Nokia Siemens Networks
Downlink Dual Carrier
VOLUME WEIGHTED LLC THROUGHPUT FOR DLDC NUMERATOR
This counter provides the numerator for Volume Weighted (VW) LLC
throughput for DLDC capable MSs with at least 4-TSL DL allocations.
The unit of the counter is 100 bytes2/10 ms. Trigger event: this
counter contains the sum of the throughputs weighted by the volume
of each LLC transmission burst within the TBF. An LLC transmission
burst is a transmission period between two transmission breaks.
Updated at the TBF release or reception of FLUSH-LL, if the size of
the TBF was 1560 bytes or more. Use case: calculations of the
Average Volume Weighted LLC Throughput for DLDC (VOLUME WEIGHTED
LLC THROUGHPUT FOR DLDC NUMERATOR/ VOLUME WEIGHTED LLC THROUGHPUT
FOR DLDC DENOMINATOR)
VOLUME WEIGHTED LLC THROUGHPUT FOR DLDC DENOMINATOR
This counter provides the denominator for Volume Weighted (VW) LLC
throughput for DLDC capable MSs with at least 4-TSL DL allocations.
Trigger event: this counter contains all the bytes transmitted
within the TBFs. Updated at the TBF release or reception of
FLUSH-LL, if the size of the TBF was 1560 bytes or more Use case:
calculations of the Average Volume Weighted LLC Throughput for DLDC
(VOLUME WEIGHTED LLC THROUGHPUT FOR DLDC NUMERATOR/ VOLUME WEIGHTED
LLC THROUGHPUT FOR DLDC DENOMINATOR)
Presentation / Author
Transmission burst – continuous data flow - the transmission period
between two transmission breaks
* © Nokia Siemens Networks
Downlink Dual Carrier
Dimensioning
The DLDC dimensioning (planning) activities on top of (E)GPRS are
listed below:
Operators’ business plan investigation
Good understanding of current and future business plans (traffic
figures with service types) for creating the most suitable BSS plan
with DLDC or supports the operator to investigate the possible
business scenarios for PSW and DLDC services.
Operators’ BSS network structure audit
Current and future CS and PS BSS network structure investigation of
the hardware usage, software usage and capacity figures /
limits.
Deployment plan preparation
The proper (E)GPRS BSS deployment plan is needed to find the way
how the highest (E)GPRS – DLDC data rate with as less quality
decrease as possible on CSW traffic can be achieved.
Capacity calculations based on deployment plan
Available / required air interface capacity and network element
connectivity calculations
Parameter setting
Presentation / Author
IP/MPLS/IPoATM
IP v.s. FR
SGSN
RLC/MAC TSL data rate
The aim behind the preparation of deployment plan:
Maximize the TSL data rate (RLC/MAC), multislot usage and dual
carrier usage
Minimize the impact of PSW services on CSW services (and vice
versa)
Take all the hardware and software considerations into
account
Controlled investment
Cell / segment option creation
The options can cover most of the cell/segment configurations of
the network
These options can be analyzed in details, so the time consuming
cell/segment based analysis is not needed
All the options are examples and can have different channel
configuration
Detailed analysis is based on layer, signaling, CS and PS traffic
point of view
Presentation / Author
S13 -> S14 conversions are required.
A valid DLDC license is required. Also PCU2 license and EGPRS
license are needed.
GPRS and EGPRS are enabled in segment and DLDC is enabled in
BTS.
BTS has 2 normal area TRXs which are EGPRS enabled and they belongs
to same DAP
The first GPRS territory TRX must be selected from such an EDAP
that contains at least two GPRS TRXs.
When selecting the next GPRS territory TRX to be upgraded, TRX from
same EDAP is selected, if possible.
Value of parameter Prefer BCCH frequency GPRS (BFG) is taken into
account also in DLDC enabled BTS even if it would mean that EDAP
selection is not optimal from DLDC point of view.
BTS parameter CDEF has that kind of value that the PS territory is
split onto two TRXs
S
a
a
a
a
a
d
d
d
d
S
S
d
d
d
d
d
D
B
B = BCCH
S = SDCCH
Layer planning, signaling, CS and PS traffic
PCU type
In PCU2-D/U, the DLDC territory on the BCCH TRX gives higher
connectivity capacity than one in non-BCCH TRX: the DSP channels
are used more efficiently better user throughput in BCCH TRX
In PCU2-E, however, the non-BCCH TRX gives higher connectivity
capacity (full usage of 16 RTSL) better site throughput in non-BCCH
TRX
Recommended and minimum CDEF values for DLDC cells as number of
RTSL
Presentation / Author
PCU2-E dimensioning – 90% table
PCU2-E Abis channel 90% utilization leaves 102 channels available
for dynamic allocation (territory upgrades)
This is sufficient for most cases especially for large EGPRS site
configurations
The table indicates the maximum number of DAPs (~(E)GPRS sites) or
DAP groups per PCU2-E as a function of DAP [TSL] and CDEF sum
[RTSL]
Presentation / Author