07 RA41217EN50GLA0 Power Control

LTE Radio Parameters RL50 Power Control

RA41217EN50GLA0

©2014 Nokia Solutions and Networks. All rights reserved.

Nokia Solutions and Networks Academy

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Contents 1. 2. 3. 4. 5. 6. 7. 8. 9. 10.. 10 11.. 11 12. 13.

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LTE Fu Func nctio tiona naliliti ties es & Fea Featu ture res s Ove Overv rvie iew w Para Pa rame mete terrs Str Struc uctu ture re & SIB SIBs s Phys Ph ysic ical al Cha Chann nnel el Con Confi figu gura rati tion on & Ran Rando dom m Ac Acce cess ss UE St State Ha Handling Bearer Management Admission Control Powe Po werr Co Cont ntro roll & Po Powe werr Se Settti ting ng Adap Ad apti tive ve Mo Modu dula lati tion on & Co Codi ding ng MIMO Mo Mode Co Control Idle Id le Mo Mode de Mo Mobi bilility ty Conn Co nnec ecte ted d Mode Mode Mobil Mobilit ity y Scheduler SON

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Module Contents • • • • • • • • •

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Overview UL-PC: Overview UL-PC: PUSCH UL-PC: PUCCH UL-PC: Control Scheme UL-PC: Closed Loop DL-PC: RL30 DL-PC: PC on PDCCH Graceful Cell Shutdown

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Overview Objective Improve cell edge behaviour, reduce inter-cell interference and power consumption. Downlink (DL) DL ‘Semi‘Semi-static’ Power Setting eNodeB gives fixed power density per PRB scheduled PRB scheduled for transport. Total Tx power is max. when all PRBs are scheduled sc heduled No adaptive/dynamic power control (O&M parameter) Cell Power Reduction level CELL_PWR_RED [0...10] dB attenuation in 0.1 dB steps dlCellPwrRed DL Power Control on PDCCH

Reduction of DL Tx power; deducted from max. antenna TX power. power. LNCEL; 0..10; 0.1; 0 dB

Uplink (UL) Slow Uplink Power Control - Com Combin binati ation on of of open open loop loop PC and and close closed d loop loop PC PC - Open Loop Power Control (OLPC) • Calculated at the UE based on pathloss measurements - Closed Loop Power Control (CLPC) • Based on exchange of feedback data and commands between UE and eNodeB • SW-licensed enhancement (can be switched on and off) 6

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Overview UL-PC: Overview UL-PC: PUSCH UL-PC: PUCCH UL-PC: Control Scheme UL-PC: Closed Loop DL-PC DL-PC: PC on PDCCH Graceful Cell Shutdown

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UL-PC: Overview LTE: orthogonal UL Tx, i.e. near-far-problem much less severe than WCDMA  • UL: dynamic, slow PC – PC – Open Open Loop (OL) & Closed Loop (CL) • need for PL / shadowing etc. compensation  OL PC • need for correction/ correct ion/ adjustments of e.g. open loop inaccuracies  CL PC Signal strength S: Depends on PL, indoor loss etc., i.e. location

Low

High

Interference (I) - main cause: inter-cell Noise (N) = kB T Df + NFeNB

Power control does not control the absolute UE Tx power but the Power Spectral Density (PSD),, power per Hz, for a device. The PSDs at the eNodeB from different users have to (PSD) be close to each other so the receiver doesn’t work over a large range of powers. Different data rates mean different Tx bandwidths so the absolute Tx power of the UE will also change. PC makes that the PSD is constant independently of the Tx bandwidth. 8

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Overview Procedure for Slow UL Power Control - UE cont control rols s the the Tx Tx powe powerr to kee keep p the the transmitted power spectral density (PSD) constant independent constant independent of the allocated transmit bandwidth (#PRBs) - If no feedba feedback ck from eNodeB eNodeB ( in the PDCCH UL PC command) command) the UE performs performs open loop PC based on path loss measurements - If feedback feedback from eNode eNodeB B the UE corre corrects cts the PSD when when receiving receiving PC PC commands from eNodeB ( in the PDCCH UL PC command) command) - PC comma commands nds (up and and down) down) base based d on UL quali quality ty and and signal signal level meas measurem urements ents

- Applied separately for PUSCH, PUCCH - Scope of UL PC is UE level level ( perform performed ed separate separately ly for each each UE in a cell) 2) SINR measurment 3) Setting new power offset

4) TX power level adjustment with the new offset 1) Initial TX power level

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UL-PC: PUSCH Equation

PPUSCH (i) :PUSCH Power Pow er in subframe i Open Loop (OL)

Closed Loop (CL)

P PUSCH (i)  min { P CMAX ,10 log log10 ( M PUSCH (i))  P O_PUSCH ( j )   ( j )  P PL L  DTF (i)  f (i)} dBm dBm

*PH = Power Headroom 11

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UL-PC: PUSCH

P PUSCH (i)  min { P CMAX ,10 log10 ( M PUSCH (i))  P O_PUSCH ( j )   ( j )  P PL L  D TF (i)  f (i)} dBm dBm PH PH (i)  P CMAX  10 log log10 ( M PUSCH (i))  P O_PUSCH( j )    PL PL  DTF (i)  f (i) PPUSCH (i) :PUSCH Power in subframe i PCMAX: max. allowed UE power (23 dBm for class 3) MPUSCH: number of scheduled RBs (The UE Tx. Power increases proportionally to # of PRBs) PO_PUSCH(j) = PO_NOMINAL_PUSCH (j) + PO_UE_PUSCH(j)

PL: pathloss [dB] = referenceSignalPower referenceSignalPower – – higher higher layer filtered RSRP DTF (i)

= 10 log 10 (2MPR Ks – 1) – 1) for Ks = 1.25 else 0, MPR = TBS/NRE, NRE : number of RE

Ks defined by deltaMCS-Enabled , UE specific

f(i): TPC (Closed Loop adjustment) Semi-persistant: j=0 / dynam dynamic ic scheduling: j=1 PO_NOMINAL_PUSCH (0,1): cell specific (SysInfo) PO_UE_PUSCH(0,1): UE specific (RRC)  (0,1)

= 0.0, 0.4, 0.5, 0.6, 0.7, 0. 7, 0.8, 0.9, 1.0 (partial PL compensation by open loop) loop)

Random access grant: j=2 PO_NOMINAL_PUSCH (2): PO_PRE + DPreamble_Msg3  (2) 12

= 1.0 1. 0 (i.e. full PL compensation) RA41217EN50GLA0

PO_UE_PUSCH(2) = 0 *PH = Power Headroom ©2014 Nokia Solutions and Networks. All rights reserved.

dB

Open Loop PC vs. Closed Loop PC Open Loop Power Control Target: provide a basic operating point for a suitable PSD for an average MCS (average SINR):

Basi B asic c _ Operating _ P Po o int  P O_PUSCH( j )   ( j )  P PL L • Open Loop Power Control takes into account effects like inter-cell interference and shadowing s hadowing • Based on PL (Pathloss) Closed Loop Power Control f(i) adjustments Target: Fine tuning around the basic operating point • Adapt dynamically to the channel conditions (take into account e.g. fast fading) • Correct the estimations of power from the open loop PC ulpcEnable enable UL closed loop PC LNCEL; true, false; false 13

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PSD: Power Spectral Density


Open Loop PC

P PUSCH (i)  min { P CMAX ,10 log10 ( M PUSCH (i))  P O_PUSCH ( j )   ( j )  P PL L  D TF (i)  f (i)} dBm dBm PO_PUSCH(j) = PO_NOMINAL_PUSCH(j) +

PO_UE_PUSCH(j)

j=0 -> PUSCH transmission with semi-persistent grant (not in RL50) j=1 -> PUSCH transmission with dynamic scheduling j=2 -> PUSCH transmission for random access grant

PO_NOMINAL_PUSCH(j) -> cell specific component signaled from system information for j=0, 1 This term is a common power level for f or all mobiles in the cell (used to t o control SINR) p0NomPusch Nominal Power for UE PUSCH Tx Power Calculation LNCEL; -126..24dbm; 1; -100 dBm

PO_UE_PUSCH(j) -> UE specific component provided by higher layers (RRC) for j=0,1

This term is a UE specific offset used to correct the errors from the t he estimation of the pathloss. p0NomPusch - This parameter defines the UE-specific nominal power for the PUSCH. Used for P0_PUSCH calculation in UE uplink power control equation (P1) for controlling the mean received SNR for user data during (re)transmission corresponding to a received PDCCH with DCI format 0 associated with a new packet transmission. This parameter is used to control mean received SNR for user data. data . 14

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PUSCH Formula

P PUSCH (i)  min { P CMAX ,10 log10 ( M PUSCH (i))  P O_PUSCH ( j )   ( j )  P PL L  D TF (i)  f (i)} dBm dBm PL: pathloss [dB] = referenceSignalPower referenceSignalPower – – higher layer filtered RSRP

This path loss compensation factor a is adjustable by Alpha

O&M. α is a cell - specific s pecific parameter (broadcasted on BCH).

1.0]] α  [0.0, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1.0 α = 0 , no compensation α = 1 , full compensation ulpcAlpha LNCEL; 0, 0.4..1.0; 0.1; 1.0

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α ≠ { 0 ,1 } , fractional compensation ©2014 Nokia Solutions and Networks. All rights reserved.

Conventional & Fractional PC • Conventional PC schemes: schemes : • Attempt to maintain a constant SINR at the receiver • UE increases the Tx power to fully compensate for increases in the path loss - Fractional PC schemes: schemes : • Allow the received SINR to decrease as the the path loss increases. • UE Tx power increases at a reduced rate as the path loss increases. Increases i n path loss are only partially compensated. • [+] [+]:: Improve air interface efficiency & efficiency & increase average cell throughputs by reducing Inter-cell interference - 3GPP specif specifies ies fractiona fractionall power control control for for the PUSCH PUSCH with the the option option to disable disable it & revert to conventional based on α UL SINR

Conventional Power Control: α=1 If Path Loss increases by 10 dB the UE Tx power increases by 10 dB

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UE Tx Power

UL SINR

UE Tx Power

Fractional Power Control: α ≠ { 0 ,1} If Path Loss increases by 10 dB the UE Tx power increases by < 10 dB


MCS dependent component

P PUSCH (i)  min { P CMAX ,10 log10 ( M PUSCH (i))  P O_PUSCH ( j )   ( j )  P PL L  D TF (i)  f (i)} dBm dBm MPR MPR K s

DTF (i )  10 log10 (2

0

 1)

for

K S

 1.25

Otherwise

deltaTfEnabled Enabled TB size (MCS) impact to UE PUSCH power calculation LNCEL; Yes/No; -

MPR = TBS/NRE with NRE : number of RE, TBS = Transport Transport Block Size

• • •

TF = Transport Format

•

Could be seen as dynamic offset of the TX power: when the BTS changes the MCS for the UE then t hen the UE indirectly may adapt the power

•

Increase the power if the Transport Format (MCS, TBS size, Number of Resource Blocks) it is so selected to increase the number of bits per Resource Element

Ks - Enabling/disabling of the transport format dependent offset on a per UE basis If this parameter is enabled, PUSCH power calculation in UE uplink power control equation takes the Transport Transport Block size in account during the power calculation

Ks - Enabling/disabling of the transport format dependent offset on a per UE basis. If this parameter is enabled, PUSCH power calculation in UE uplink power control equation (P1) takes the Transport Block size in account during the power calculation. 17

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UL-PC: PUCCH

P PUCCH(i)  min{ P MAX , P 0_PUCCH  P PL L  h(nCQI , n HAR dBm m HARQ )  D F_PUCCH( F )  g (i)} dB PPUCCH: PUCCH Power in subframe i Pmax: max. allowed power P0_PUCCH = P0_NOMINAL_PUCCH + P0_UE_PUCCH

p0NomPucch Nominal Power for UE PUCCH Tx Power Calculation LNCEL; -126..-96; 1; -100 dB

P0_NOMINAL_PUCCH : cell specific (SysInfo) P0_UE_PUCCH : UE specific (RRC) PL: pathloss pathloss [dB] = referenceSignalPower referenceSignalPower – – higher higher layer filtered RSRP H(nCQI, nHARQ ) • PUCCH format 1, 1a, 1b: h(n) = 0

* For PUCCH higher degree of orthogonality could be assumed due to the usage of the orthogonal codes so alpha=1 (full compensation)

• PUCCH format 2, 2a, 2b and : h(n) = 0 if nCQI < 4 h(n) = 10log10 (nCQI/4) otherwise (here: normal CP, CP, for f or extended CP also nHARQ to be considered, n:number of information bits) F_PUCCH (F) (see next slide)

: dFListPUCCH

g(i): TPC (closed loop adjustment) 19

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Compensation Factor for different PUCCH formats For example if format 1a (1ACK) is having offset 0 then format 1b (2ACK) could have offset 3dB ©2014 Nokia Solutions and Networks. All rights reserved.

deltaFListPUCCH Parameters

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Name

Object

Abbreviation

Range

Description

Default

DeltaF PUCCH List

LNCEL

dFListPucch

n/a

dFListPucch: SEQUENCE (see values below)

n/a

DeltaF PUCCH Format 1

LNCEL

dFpucchF1

-2, 0, 2 dB

Used to define the PUCCH format 1

0 dB

DeltaF PUCCH Format 1b

LNCEL

dFpucchF1b

1, 3, 5 dB

Used to define the PUCCH format 1b

1 dB

DeltaF PUCCH Format 2

LNCE

dFpucchF2

-2, 0, 1, 2 dB

Used to define the PUCCH format 2

0 dB

DeltaF PUCCH Format 2a

LNCE

dFpucchF2a

-2, 0, 2 dB

Used to define the PUCCH format 2a

0 dB

DeltaF PUCCH Format 2b

LNCEL

dFpucchF2b

-2, 0, 2 dB

Used to define the PUCCH format 2b

0 dB

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Module Contents • • • • • • • • • •

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Overview UL-PC: Overview UL-PC: PUSCH UL-PC: PUCCH UL-PC: Control Scheme UL-PC: Closed Loop UL-PC: Parameters DL-PC: RL30 DL-PC: PC on PDCCH Graceful Cell Shutdown

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UL-PC: Control Scheme Open loop: level based Interference: considered by P 0 values  not need for explicit signaling RRC-BCCH:: RRC-BCCH P0_NOMINAL_PUSCH, P 0_NOMINAL_PUCCH, ALPHA, deltaFListPUCCH, deltaPreambleMsg3

PDCCH:: DELTA_PUSCH, DELTA_PUCCH PDCCH MPUSCH taken from scheduling grant

Data

RRC-DCCH: P0_UE_PUSCH, P0_UE_PUCCH, RRC-DCCH: DELTA_TF_ENABLED, ACCUMULATION_ENABLED, P_SRS_OFFSET, P_SRS_OFFSET, filterCoefficient

UE: PL SIB1, UE class: P CMAX

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UL-PC: Closed loop - PUSCH (example)

Closed loop adjustments: f(i) = f(i-1) +

PUSCH (i

- KPUSCH)

i.e. recursive determination

ulpcEnable enable UL closed loop PC LNCEL; true, false; false

or

f(i) = where

PUSCH (i PUSCH is

- KPUSCH) i.e. absolute setting

the signaled TPC in subframe i-K PUSCH

For FDD: KPUSCH = 4

P (closed loop)

t 24

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UL-PC: Closed Loop - Process ulpcUpqualSch High Thresh. For SINR for PUSCH LNCEL; -47...80dB; 1dB ; 11dB

Decis ion ma matri rixx

1dB SINR

+ 1 dB or + 3 dB

ulpcUpqualCch High Thresh. For SINR for PUCCH LNCEL; -47...80dB; 1dB ; 4dB

- 1 dB

- 1 dB

1

2

3

UP_QUAL_**

+ 1 dB or + 3 dB

ulpcLowqualCch Low Thresh. For SINR for PUCCH LNCEL; -47...80dB; 1dB ; 1dB

+ 1 dB or + 3 dB

+ 1 dB or + 3 dB 7

LOW_LEV_**

ulpcLowlevSch Low Thresh. For RSSI for PUSCH LNCEL; -127...0dBm;1dBm ;;-103dBm RA41217EN50GLA0

5

6

1dB

ulpcLowlevCch Low Thresh. For RSSI for PUCCH LNCEL; -127...0dBm;1dBm ;;-103dBm

25

-1 dB

4

LOW_QUAL_**

ulpcLowqualSch Low Thresh. For SINR for PUSCH LNCEL; -47...80dB; 1dB ; 8dB

0 dB

Decision whether to +1dB or +3dB

+ 1 dB or + 3 dB 8

UP_LEV_**

9

RSSI

ulpcUplevCch High Thresh. For RSSI for PUCCH LNCEL; -127...0dBm;1dBm ;;-98dBm ulpcUplevSch High Thresh. For RSSI for PUSCH LNCEL; -127...0dBm;1dBm ;;-98dBm



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Overview UL-PC: Overview UL-PC: PUSCH UL-PC: PUCCH UL-PC: Control Scheme UL-PC: Closed Loop DL-PC:RL30 DL-PC: PC on PDCCH Graceful Cell Shutdown

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DL-PC RL20: (static) cell power reduction • based on single parameter CELL_PWR_RED = 0.0, 0.1 … 10.0 dB •  cell size adjustment and coverage control • flat Power Spectral Density (PSD) • semi-static MIMO_COMP (if enabled)

RL30: optional power boost: PCFICH, PHICH, DL RS

PSD

PSD

PSD = (Max_TX_Pwr – – CELL_PWR_RED) – 10*log10( 12*# PRBs)

Alloca Allocated ted DL PRBs PRBs

Frequency

DL Pilots 27

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dlCellPwrRed Reduction of DL Tx power; deducted from max. antenna TX power. power. LNCEL; 0..10; 0.1; 0 dB pMax Maximum output power LNCEL; 37.0 (0), 39.0 (1), 40.0 (2), 41.8 (3), 43.0 (4), 44.8 (5), 46.0 (6), 47.8 (7);(7); 37.0 dBm = 5 W 39.0 dBm = 8 W 40.0 dBm = 10 W 41.8 dBm = 15 W 43.0 dBm = 20 W 44.8 dBm = 30 W 46.0 dBm = 40 W 47.8 dBm = 60 W

PSD = (Max_TX_Pwr – – CELL_PWR_RED) – 10*log10( 12*# PRBs)

PDCCH

Time

PDSCH, PCH BCH, SCH ©2014 Nokia Solutions and Networks. All rights reserved.

DL-PC: Power Reduction Cell Power Reduction PSD = (pMax - CELL_PWR_RED) CELL_PWR_RED) - 10*log10( # PRBs_DL PRBs_DL *12) - MIMO_COMP MIMO_COMP [dBm]

PSD: Power Spectral Density, which specifies the constant absolute Power per 15kHz Resource Element (RE) • pMax: maximum eNodeB transmit power per Antenna in [dBm] • CELL_PWR_RED:

O&M parameter

• # PRBs_DL: maximum Number of downlink PRBs in given LTE Carrier Bandwidth • MIMO_COMP: Compensation Factor • MIMO_COMP = 0 dB for SISO/SIMO • MIMO_COMP MIMO_COMP = 0...12 dB for MIMO Diversity and for MIMO Spatial Multiplexing - PS D g iven per ante antenna nna (R F ampl amplifier ifier output output)) - PR B s not sc hedule heduled d are are blan blanked ked

dlpcMimoComp Determines the power compensation factor for antennaspecific maximum power in case of a downlink transmission using at least two TX antennas LNCEL; 0..10; 0.01; 0 dB

Applied to UE / cell specific channels and signals: • PSD_CELL_CTRL for BCCH i.e. PBCH+PDSCH, PCFICH and PCH • PSD_CELL_RS for reference signals (RS) / pilots • PSD_CELL_SYNC for synchronization synchronization channel • PSD_UE_PDSCH for UE specific part of PDSCH

dlCellPwrRed Reduction of DL Tx power; deducted from max. antenna TX power. LNCEL; 0..10; 0.1; 0 dB

• PSD_UE_CTRL for PDCCH and PHICH 28

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PRS power boosting

OTDOA – related OTDOA – related - PR PRS S po pow wer bo boos osti ting ng • Goal: Improve hearability of the PRS • Reuse of 6 and with respect to the allocation in frequency domain of OFDM symbols carrying PRS -

PRS boosti tin ng: 10*log 10 (6) = 7.78dB

prsPowerBoost

LNCEL, -3.. .7.78 dB, 0 dB

• De-boosting up to 3 dB is possible (in case there are interference problems with PRS signals)

PRS = PRS = Positioning Reference Signals 29

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DL-PC: DL power boosting for control channels • Power offsets to the PCFICH, PHICH, DL RS. • Introduced with RL30 (LTE430). • Better detection of PCFICH indicating the number of OFDM symbols for the PDCCH. • Better channel estimation in case of RS boosting may im prove HO performance. • Higher reliability reliabili ty of ACK/NACK transmission transmission via PHICH.

PCFICH OFDM symbols

The eNB ensures that total Tx power is not exceed, i.e. the sum power for any OFDM symbol must not exceed the committed maximum power, otherwise all the configured boosts (PHICH) may not be applied. Subcarrier power boosting is only allowed if the excess power is withdrawn withdrawn from the remaining subcarriers. Coverage in LTE LTE is very ver y often limited by UL, and in such cases it does not make much sense to improve the coverage in DL. UL coverage should be checked before applying DL control channels power boost. RS OFDM 30

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symbols


DL-PC: DL power boosting for control channels PCFICH power boosting PCFICH provides information about the number of OFDM symbols for the PDCCH. The eNB supports dedicated power control settings for the PCFICH in order to ensure that especially cell edge UEs can pr operly receive the PCFICH.

dlPcfichBoost Downlink PCFICH transmission power boost LNCEL; 0..6; 0.1; 0.1; 0 dB

A relative relative offset between between the flat PSD (Power Spectral Spectral Density) on PDSCH and PCFICH can be configured by O&M on cell level.

PHICH power boosting The PHICH provides ACK/NACK information for the uplink transmission. The eNB supports dedicated power control settings for the PHICH in order to ensure that the UE can properly receive the PHICH.

dlPhichBoost Downlink PHICH transmission power boost LNCEL; 0..6; 0.1; 0 dB

PHICH power boost may not be (fully) applied if PDCCH PSD goes too low in the first OFDM symbol. In that case, the eNB rises the PHICH Power Boost not applied warning. A maximum maximum relative offset between the flat PSD on PDSCH and PHICH PHICH can be configured configured by O&M on cell cell level.

Downlink reference signal boosting The downlink reference symbols are used by the UE for

dlRsBoost

channel estimation and cell measurements (Level, Quality) for mobility.

Downlink RS transmission power boost LNCEL; 0dB (0), 1.77dB (1), 3dB (2), 4.77dB (3), 6dB (4); 0 dB

The eNB supports relative RS / PDSCH power control settings. A relative relative offset between between the PDSCH and RS can be configured by O&M on cell level. The eNB ensures that total Tx power is not exceed.

The sum power for any OFDM symbol must not exceed the committed maximum power, otherwise all the configured boosts (PHICH) may not be applied. 31

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Module Contents • • • • • • • • • •

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Overview UL-PC: Overview UL-PC: PUSCH UL-PC: PUCCH UL-PC: Control Scheme UL-PC: Closed Loop UL-PC: Parameters DL-PC DL-PC: PC on PDCCH Graceful Cell Shutdown

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Main target of DL-PC-CCH

- DL Powe Powerr Control Control for PDCCH is an additi additional onal mechanism mechanism interact interacting ing with with DL AMC for PDCCH in order to make the signaling as robust as possible - DL-PCDL-PC-CCH CCH aims aims at 1% targe targett BLER but cannot cannot modify modify AGG assignm assignments ents - Ma Main in actio actions ns perfo perform rmed ed by DL-P DL-PC-C C-CCH CH • Power reduction on reduction on CCEs with assigned AGG level higher than required (or equal • Power boosting on boosting on CCEs with assigned AGG level lower than required • Equal power relocation among relocation among all scheduled CCEs



• Macro cell case #1 • Uniform UE distribution

Very good CCEs (CQI CCEs (CQI highly above 1% BLER target) 

Bad CCEs (AGG CCEs (AGG level too high to meet 1% BLER target) 

If still some power available, available , relocate equally among all CCEs

4-CCE 8-CCE

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2-CCE

1-CCE

enableLowAgg Enable lower aggregation selection for PDCCH LA . LNCEL; True/False; False


Principles of DL-PC-AMC - PDCCH PDCCH Po Powe werr Con Contr trol ol ca can n be be enabled/disabled by O&M switch - Maximum transmit power of the Power Amplifier cannot be exceeded ( exceeded ( pMax pMax ; O&M) - Reduct Reduction ion and and boosting boosting range is strictl strictly y defined defined and and is always always consider considered ed as the limit for power level modification - DL-P DL-PC-CC C-CCH H oper operates ates toget together her with DL-AM DL-AMC-C C-CCH CH on TTI basis - DCI mess message ages s with with mor more e than than one one CCE (AG (AGGG-…>1) …>1) have a flat PSD, thus all CCEs belonging to one scheduled UE are transmitted with the same power Short Name

34

Description

Range/ Step

Default Value

Parameter Scope

true, false

true

Cell

Changing parameter requires object locking. Operator configurable.

Remark

enablePcPdcch

Enabling/disabling PC for PDCCH. In case the parameter is disabled, a flat downlink PSD is used.

pdcchPcBoost

Maximum power boost per CCE.

0...10 dB, step 0.1 dB

4 dB

BTS

Not modifiable. Vendor configurable.

pdcchPcRed

Maximum power reduction per CCE.

0...10 dB, step 0.1 dB

6 dB

BTS


pdcchPcReloc

Maximum limit on the equal power relocation per CCE.

0...10 dB, step 0.1 dB

3 dB

BTS


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Graceful Cell Shutdown Reduced Service Impact

• Stepwise downlink power reduction in order to enforce active and idle mode mobility to other cells layers

• Operator configurable settings

enableGrflShdn The parameter enables the feature 'Graceful Cell Shutdown'. LNBTS; Disabled (0), Enabled (1); Enabled (1)

DL power

time handover or cell reselection

Change administrative state of a cell to ‘shutting down’ Automatic lock feature 36

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Graceful Cell Shutdown

• The eNode B reduces stepwise the DL power to a minimum power level • The number of steps and the shutdown time is operator configurable • The broadcasted power for the reference symbols is not changed, i.e. UE assumes that the eNode B power is unchanged

• A wait timer of 10 seconds is applied after the last power down step before the administrative state is set to locked and the operational state is set to disabled.

shutdownStepAmount Number of Steps for Graceful Cell Shutdown LNBTS; 1...16;1; 6

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RA41217EN50GLA0

shutdownWindow Time Interval for Stepwise Output Power Reduction for Graceful Cell Shutdown LNBTS; 6...180;6; 60


07 RA41217EN50GLA0 Power Control

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