umts induction training (general intorduction to hspa) v1.4

8/10/2019 UMTS Induction Training (General Intorduction to HSPA) v1.4

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1 Nokia Solutions and Networks Baraski/ MBB CS NetEng

For internal use

UMTS Induc t ion train ing

General Introduction to HSPAMichaBaraski

MBB CS NetEng

Network Engineering WCDMA Radio


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For internal use

HSDPA Highlights

Peak data rates increased to significantly higher than 2 Mbps;Theoretically exceeding 10 Mbps

Retransmissions delay reduced

Used Solutions

Adaptive modulation and coding QPSK, 16-QAM and 64QAM

Layer 1 HARQ (Hybrid Automatic Repeat reQuest)

Short frame 2 ms


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For internal use

New Channels introduced with HSDPA

User data is carried on:

high-speed downlink shared channel (HS-DSCH)

Signalling is carried on:

high-speed shared control channel (HS-SCCH)

high-speed dedicated physical control channel (HS-DPCCH) DCH (Rel99)


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For internal use

High-speed downlink shared channel

mapped on the high-speed physical downlink shared channel(HS-PDSCH)

User A

Us

er BUser C

NodeB w/o HSDPA NodeB w/ HSDPA

User CUser B

User A

Fat pipe is shared among UEs

Release 5

Dedicated pipe for every UE

Release `99


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For internal use

Support of higher order modulation than the DCH

HSDPA uses both QPSK, 16-QAM and 64-QAM

16-QAM requires also amplitude estimation from CPICH fordetection

Only turbo-coding is used Different Coding rates possible: from 0.143 to 0.887

High-speed downlink shared channelModulation & Coding

16 QAMRel5

64 QAMRel7

QPSKRel99


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For internal use

High-speed downlink shared channelLink adaptation

Lack of fast power control

Link adaptation selects the suitable combination of codes, coding ratesand modulation to be used


7/598 Nokia Solutions and Networks Baraski/ MBB CS NetEng

Fast Packet Scheduling:

Node B decides allocation of HSDPA resources to UE every TTI = 2 ms

supported Packet Scheduler algorithm*:

Round Robin RR

Proportional Fair PF(requires individual license)

* Type of scheduler set by

HSDPA.BB.Resource.Allocation commissioningparameter

Round Robin (RR)

assigns sub-frames in rotationUser at cell edge served as frequentlyas user at cell centre

doesnt account for UEs channelconditions

Low total throughput in cell

if no data have to be transferred tocertain UE then sub-frame assigned to

next UE

High-speed downlink shared channelPacket schduling (1/2)



TTI 1 TTI 2 TTI 3 TTI 4

USER 1 Es/N0USER 2 Es/N0

Scheduled user

Proportional Fair (PF)

Takes into account multipath fading conditions experienced by UE

Improved total throughput in cell compared to RR

Sub-frames assigned according scheduling metric

Ratio instantaneous data rate / average data rate experienced in the past

User at cell edge served less frequently as user at cell centre

High-speed downlink shared channelPacket schduling (2/2)



For internal use

Example CQI Mapping Table

BTS can map thereceived CQI value forthe data rate to beused in the linkadaptation

Necessary conversionto be done dependingon BTS poweravailability

Reference power

adjustment usedwhen quality wouldallow higher rate thanUE capability



For internal use

UE HS-DSCH Categories

Each UE which isHSDPA capable hasits Category

UE Categories arespecified by 3GPP

UE Categoriesspecifies max UEcapabilities



For internal use

High-speed downlink shared channelHSDPA L1 Retransmissions

Rel99only RLC retransmissions are used

HSDPA physical layer retransmissions and retransmission combining

RLC retransmissions applied when L1 retransmissions failed


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For internal use

High-speed downlink shared channelHSDPA L1 Retransmissions soft combining

Here the rate matching

functionality is identical

between transmissions and

always the same bits remain

after rate matching operation

and are sent.


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For internal use

High-speed downlink shared channelHSDPA L1 ReTX incremental redundancy

Requirement more

memory at UE

The relative number ofparity bits to

systematic bits varies

between

retransmissions

Uses a different ratematching between

retransmissions


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For internal use

High-speed downlink shared channelMulticodes

All codes to which

HSDPA transmission

is mapped

(5 in this example)

Data to UE #1 Data to UE #2 Data to UE #3 CodeCode

Time

SF=8

SF=16

SF=4

SF=2

SF=1

P hysicalchannels (codes) to which HS-DSCH is mapped

SFHSDPA = 16

Number of codes to which HSDP A t ra nsm issi on ismapped: 12 (exam ple)

TTI = 2 ms

Multicode operation with a fixed spreading factor SF=16


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For internal use

High-speed downlink shared channelMulticodes

Exemplary codes allocation:


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For internal use

High-speed downlink shared channelOther properties

User allocation with base station based scheduling every

2 ms, with fast physical layer signalling.

Lack of soft handover. Data are sent from one serving HS-DSCH cell only.

Lack of physical layer control information on the HS-PDSCH.

This is carried instead on the HS-SCCH for HSDPA use andon the associated DCH (uplink power control, etc.)

No discontinuous transmission (DTX) on the slot level. TheHS-PDSCH is either fully transmitted or not transmitted at allduring the 2-ms TTI.


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For internal use

High speed shared control channel(HS-SCCH)

carries time-critical signalling information which allows the

terminal correctly read HS-DSCH

Information that allows to

de-spread of correct codesand apply right modulation

ARQ process is being

transmitted

Redundancy version andconstellation

Transport block size


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For internal use


Only one HS-SCCH needed if only time multiplexingis used

More than one HS-SCCH needed if time & code multiplexingis used


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For internal use


Up to 4 HS-SCCH codes in cell (4 users simultaneously)

Using spreading factor 128

Modulated with QPSK

No pilot or power control bits are carried phase reference is always the same as for the HS-DSCH

One-third convolutional coding turbo-coding does not make sense with such a small amount of

information

ARQ (Automatic Repeat reQuest ) info is additionally

protected with CRC Wrong HARQ process number can cause buffer corruption


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For internal use

High-speed dedicated physical controlchannel (HS-DPCCH)

Uplink channel that carries the uplink HSDPA related L1

control information to the BTS

HS-DPCCH uses a fixed spreading factor of 256

Timing from downlink packet to uplink feedback (ACK/NACK)is fixed thus network knows for which packet the info is

related to


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For internal use

High-speed dedicated physical controlchannel (HS-DPCCH)

The HARQ feedback informs the base station whether the

packet was decoded correctly or not

Channel quality information (CQI), respectively, tells the basestation scheduler the data rate the terminal expects to be ableto receive at a given point in time.

the CQI transmission frequency is parameterized CQI information can be also repeated, valid for cell edge operation:

the available power would not ensure sufficient quality for feedbackreception

when terminal has to reduce the uplink transmission power level if any ofthe cells in the active set sends a power-down command


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For internal use

HSDPA & Soft Handover

In case of DCH all data is sent from all active set BTSs

In case of HSDPA, HS-DSCH sent from one BTS only,associated DCH (can be low rate if only signalling) from allcells


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For internal use

HSDPA & Compressed mode

The inter-frequency measurement is handled by scheduling

HS-SCCH/HS-PDSCH are always trasnsmitted fully or thennot at all if there is any overlapp during the 2 ms TTI

Alternatively one can switch back to DCH for inter-frequencymeasurements


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For internal use

HSDPA functionalities In Network Elements

Scheduling Dynamic resource

allocation QoS provision Load and overload

control Data buffering Flow control towards

RNC

QoS parameters mapping Handover control

Admission control Radio resource reservation DL code allocation and

code three handling Load and overload control


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For internal use

UMTS Induc t ion train ingHSUPA Rel.6

High Speed Uplink Packet Access


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For internal use

HSUPA Highlights

Peak data rates increased to significantly higher than 2 Mbps;

Theoretically reaching 5.8 Mbps Reduced delay from retransmissions.

Solutions:

Layer 1 hybrid ARQ

Node B based scheduling for uplink

Frame sizes 2ms & 10 ms SF2 and SF4, and multicode transmission


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For internal use

New Channels introduced with HSUPA

User data is carried on:

enhanced dedicated physical data channel (E-DPDCH)Signalling is carried on:

enhanced dedicated physical control channel (E-DPCCH)

E-DCH absolute grant channel (E-AGCH) (scheduling support)

E-DCH relative grant channel (E-RGCH) (scheduling support) E-DCH HARQ indicator channel (E-HICH) (retransmission support)

DCH (Rel99)


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For internal use

HARQ

Synchronous N-process SAW HARQ

Timing of the uplink packet defines to which HARQ process it belongs to

Timing of the downlink ACK/NACK defines which packet is referring to

E-DPCCH carrying HARQ information to the Node B

E-HICH carrying HARQ ACK/NACK back to the UE


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For internal use

HARQ in soft handover

If the single Node B part of the active set sends an ACK the

transmission is consider as a successful. NACKs are transmitted from all of same E-DCH radiolink set

cells in order to enable combining in the receiver

MAC-es in the RNC to reorder the packets arriving in disorder

due to HARQ


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For internal use

Node B Controlled HSUPA Scheduling

Many To Onescheduler type

Scheduled resource is not power like in HSDPA case butnoise raise

Schedulers target is to keep interferences as close tomaximum as possible via controlling gain (over E-DPCCH)

factor the UE may use for E-DPDCH transmission.


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For internal use

E-DCH dedicated physical datachannel (E-DPDCH)

Used to transmit the coded E-DCH transport channel

Turbo coding, 24 bit CRC, HARQ with incrementalredundancy

SF from 2 to 256

Supports simultaneous transmission of two SF2 and two SF4


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For internal use

E-DCH dedicated physical datachannel (E-DPDCH)

The E-DPDCH is not a standalone channel, but requires

simultaneous transmission of the DPCCH with followinginformation:

pilot bits are needed for channel estimation and signal to interferenceratio (SIR) estimation purposes in the receiver

power control bit needed for downlink power control

Two TTI lengths supported, 2 ms and 10 ms


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For internal use

E-DCH dedicated physical controlchannel (E-DPCCH)

Uplink channel, used for transmitting out-of-band information

about E-DPDCH like: required for power control and uplink channel estimation

SF used is 256

Tailored to work with 2 ms TTI, when 10 ms TTI is used the

data is repeated five times, allowing reduction of power level

C


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For internal use

E-DCH dedicated physical controlchannel (E-DPCCH)

Information bits on the E-DPCCH

Retransmission Sequence Number for HARQ, 2 bits informing the HARQ sequence number of the transport block currently

being sent on E-DPDCHs

Happy-bit for scheduling, 1 bit

indicates whether the UE is content with the current data rate E-TFCI 7 bits

tells the receiver the transport block size coded on the E-DPDCH

Indicating the transport format being transmitted simultaneously on E-DPDCHs

Knows bases on upper functionality how many E-DPDCHs aretransmitted in parallel and what spreading factor is used

E HICH/E RGCH


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For internal use

E-HICH/E-RGCH

E-DCH HARQ indicator channel

Downlink physical channel used for transmitting ACKs and NACKs for uplinkpacket transmission

In SHO, each BTS sends ACK, retransmission until at least one cellresponds with an ACK

Only serving cell can send NACK saving DL transmission power

E-DCH relative grant channel Downlink physical channel used for transmitting single step-up/ downscheduling commands

Commands are affect the relative transmission power the UE is allowed to usefor data channel transmission (E-DPDCH), thus effectively adjusting the uplinkdata rate up/down.

The cells not belonging to the E-DCH serving radio link set may only transmitdown command

Only the serving cell and the other cells belonging to the same E-DCH radiolink set can increase the UEs allowed maximum relative transmission power

E DCH b l t t h l


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For internal use

E-DCH absolute grant channel(E-AGCH)

Downlink physical channel used for transmitting an absolute value of the Node B

schedulers decision UE is informed about the relative transmission power it is allowed to use for (E-DPDCH)(which in fact means the maximum transmission data rate UE may use)

SF256 channel transmitting 6 information bits and a 16-bit UEspecific CRC

5 bits for E-DPDCH/DPCCH power ratio

1 bit for process applicability

16-bit CRC used to identify to which UE the AG is for Sub-frame is repeated 5 times when 10 ms E-DCH TTI is used

HSUPA P k D t R t


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For internal use

HSUPA Peak Data Rates

Theoretical peak bit rate up to 5.76 Mbps

Two SF2 and two SF4 codes in parallel No channel coding, 0% initial transmission BLER

Initial capability Category 5 with 2 x SF2 providing 2 Mbps with 10 ms TTI

UE Category # of codes Supported TTIs 10ms 2ms

1 1 x SF4 10ms 0.73 -

2 2 x SF4 10ms and 2ms 1.45 1.45

3 2 x SF4 10ms 1.45 -

4 2 x SF4 10ms and 2ms 2.00 2.91

5 2 x SF4 10ms 2.00 -

62 x SF4

+ 2 x SF210ms and 2ms 2.00 5.76

72 x SF4

+ 2 x SF210ms and 2ms 2.00 11.20

Max L1 Data Rate [Mbps]

16QAM has

to be appliedto achieve

11.20Mbps

HSUPA f ti liti I N t k El t


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42 Nokia Solutions and Networks Baraski/ MBB CS NetEngFor internal use

HSUPA functionalities In Network Elements

Fast power control Scheduling QoS provision Load and overload

control

QoS parameters mapping Handover control Outer loop power control Packet Reordering

Admission control Initial power/SIR setting Radio resource

reservation Load and overloadcontrol


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UMTS Induc t ion train ingUTMS Summary And The Near Future

DCH HSDPA HSUPA


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DCH vs. HSDPA vs. HSUPA


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UMTS Induc t ion train ingFeatures

HSPA Data Rate Evolution


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HSPA Data Rate Evolution

14

Mbps

21-28Mbps

3GPP R53GPP R6

3GPP R7

42 Mbps84 Mbps

3GPP R83GPP R9

168 Mbps

3GPP R10

14

Mbps

0.4

Mbps

5.8

Mbps

11

Mbps

11

Mbps

23

Mbps

DC-HSDPA,

+ 64QAM

MIMO

(2x2)

DC-HSDPA

+ 64QAM

+ MIMO

(2x2)

4-carrierHSDPA

+ 64QAM

+ MIMO(2x2)

DC-HSUPA

+ 16QAM16QAM

64QAM or

16QAM

+ MIMO

(2x2)

3GPP R11

336 Mbps

8-carrierHSDPA

+ 64QAM

+ MIMO (2x2)

or4-carrierHSDPA

+ 64QAM

+ MIMO (4x4)

23Mbps

DC-HSUPA

+ 16QAM16QAM

70Mbps

DC-HSUPA

+ 64QAM

+ MIMO (2x2)

Feature


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FeatureFractional DPCH (Enhancement of Associated-DCH)

Reduced spreading codes and power overhead due to A-DCH

channels used by HSDPA users HSDPA average cell throughput can be increased due to improved

spreading code efficiency and increased number of availableHS-PDSCH (and DPCH) codes

Improved capacity in the Network and operators revenues

SLOT = 2560 chips

RX off TPC RX off

TPC

UE1

UE3

TPC

UE3TX offTX off

RX off TPC RX off

UE1

UE2T1

T1+256chips

Node B TX

RX off TPC RX off

T1+512 chips

TPC

UE2

DL L1 signaling of up to 10

HSDPA users are time

multiplexed on the sameSF256 DL code channel

Feature


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FeatureCS Voice over HSPA

transport channel DCH -> HS-DSCH / E-DCH

dejitter buffer introduced number of Voice UEs increased

battery consumption reduction

spectral efficiency increased

Feature


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FeatureHSDPA 64QAM

64 QAM modulation uses 6 bits per symbol

64 QAM can provide 3 to 15 % higher average HSDPA cell and userthroughput

Can be used only for good radio conditions - 64 QAM is more sensitive tothe quality of radio channel than 16 QAM

Peak data rate increased to 21.1 Mbps (depending on radio interfaceconditions)

16 QAM

II

Q Q

64 QAM

Feature


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FeatureHSDPA 64QAM

64QAM 16QAM QPSK 16QAM 64QAM

Serving

CellChange

Enter Soft

Handover

0%

2%

4%

6%

8%

10%12%

14%

16%

18%

20%

1 3 5 7 9 11 13 15 17 19 21 23 25 27 29CQI

0%

10%

20%

30%

40%

50%60%

70%

80%

90%

100%

PDF

CDF

QPSK 64QAM16QAM

Channel Quality

distr ibut ion fo r an

example macrocel l

Leave Soft

Handover

64QAMusage area

Feature


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FeatureMIMO

Multiple Input Multiple Output

Max UE Data Rate increased 28Mbps with 16QAM

42Mbps with 64QAM

Transmission mode

Single stream: both streams carrying same TBS TBS 1 = TBS 2

Dual stream: each stream carries different TBS

TBS 1 TBS 2 UL unchanged

TBS 1

TBS 2

Feature


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Possibility of DL scheduling of HSDPA UE within one TTI across two cells/carriers

Max UE Data Rate increased 28Mbps with 16QAM

42Mbps with 64QAM

UL unchanged (within single cell)

FeatureDual Cell HSDPA

HS - SCCH

HS - PDSCH

HS - DPCCH (ACK/CQI for both carriers)

F - DPCH

E - DPDCH/E - DPCCH

HS - SCCH

HS - PDSCH

Serving HS - DSCH cellprimary carrier

Secondary serving HS -(

UL - DPCCH

Secondary Serving High Speed Cell

Primary Serving Cell

HS-SCCH

HS-PDSCH

F-DPCH (RAN1201)

HS-

DPCCH

E-DPDCH/E-

DPCCH

UL DPCCH

+ common CHs + E-AGCH,

E-RGCH, E-HICH

HS-SCCH

HS-PDSCH

+ common CHs + E-AGCH,

E-RGCH, E-HICH

UEBTS

Feature


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FeatureDual Cell HSDPA + MIMO + 64QAM

HS-DSCH 2 HS-DSCH used, one on each carrier for DC HSDPA.

For MIMO on both these carriers :

For Dual Stream, 2 Transport Blocks are sent per TTI on each HS-DSCH (onecarrier each)

For Single Stream, 1 Transport Block is sent per TTI on each HS-DSCH

Max UE Data Rate increased 56Mbps with 16QAM 84Mbps with 64QAM


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Frequency Domain Equalizer FDE - Basics

Brief description / Motivation:

Before FDE: Node B receiver based upon RAKEreceiver technology

RAKE unable to receive high data rates even in total absence of other cellinterferenceshort spreading codes (SF2) vulnerable to ISI

FDE captures the energy from all multipath components and allows up to 2x

higher 16QAM data rates compared to a RAKE receiver

FDEcan remove ISI, leaving other users of same cell & surrounding cells to be

main limiting factors for UL data rates

Interference from other users of the own cell can reduced by HSUPA IC FDE is prerequisite for HSUPA 16QAM

PrxMaxTargetBTS

UL

Noise

PowerPrxMaxTargetBTS

4 Mbps 8 Mbps

RAKE FDEULNoise

Power

FDE: Frequency Domain Equalizer

IC: Interference Cancellation

ISI: Inter-Symbol-Interference

removes ISI

enables higher

throughput

prerequisite for

HSUPA 16QAM


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HSUPA Interference Cancellation Receiver - Basics

Brief description / Motivation:

reduces UL Intra-cell interference with non-linear Interference Cancellation

ICmethod called Parallel Interference Cancellation (PIC)

Basic PIC decreases interference from HSUPA 2 ms TTI users to other UL

channels improved coverage e.g. for AMR calls existing in parallel with peak rate users

Enhanced PICdecreases interference from HSUPA 2 ms TTI users on each

other

larger peak HSUPA data rates (also 16-QAM) Improving features FDE & HSUPA 16QAM

IC users: Users mapped on E-DCH with 2ms TTI

for which Interference Cancellation IC isappliedusually users with the highestpower

IC users do not get any direct benefit fromIC (indirectly from lower Tx power of otherusers)

Non-IC users: Rest of 2ms TTI E-DCH users, all 10ms

TTI E-DCH usersand all DCH users Interference is reduced for non-IC users

only

PIC state change of cells with PIC-Automatic is controlled by BTS

Cells with highest traffic shall be selected for ICCell are deselected for IC if traffic has decreased


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HSUPA Downlink Physical Channel Power Control:


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HSUPA Downlink Physical Channel Power Control:

RAN971 Included in RU40 basic software packageno license required

HW prerequisites: Flexi rel.2

Can be used if: Basic HSUPA, HSUPA BTS Packet Scheduler and HSUPA BasicRRM are active

Brief description:

This feature introduces power control for followingdownlink physical control channels:

E-DCH Absolute Grant Channel (E-AGCH) E-DCH Relative Grant Channel (E-RGCH)

E-DCH Hybrid ARQ Indicator Channel (E-HICH)

Fractional Dedicated Physical Channel (F-DPCH)

Controlling the transmit powers of the HSUPA downlink control channels based onthe feedback received from UE

Motivation and benefits:

Reduction of average downlink power need

The coverage area for 2ms E-DCH TTI may be increased

Increased number of CS Voice over HSPA (RU2072 users, RU40128 users)

C ti P k t C ti it CPC (2/2)


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Concept of UL Discontinuous Transmission UL GatingContinuous Packet Connectivity CPC (2/2)

UL Gating (UL DTX): reduces UL control channel (DPCCH) overhead

no data to sent on E-DPDCH or HS-DPCCH UE switchs off ULDPCCH

DPCCH Gating is precon dit ion for o ther 3 sub-features

DPDCH

DPCCH

E-DPDCH

DPCCH

E-DPDCH

DPCCH

Rel99 Service

Voice (20ms)

Rel6 Voice 2ms

(Rel6 VoIP)

Rel7 Voice 2ms

(Rel7 VoIP)

UL DPCCH

Gating

UE Categories


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UE Categories

Below is the chart for 3GPP UE categories which allow MIMO, DC HSDPA & 64 QAM to operate together.

UEcategories 16 QAM 64 QAM DC HSDPA MIMO DC HSDPA+

MIMO

DC HSDPA+

64 QAM

MIMO+

64 QAM

DC HSDPA +MIMO +

64 QAM

13 - - - - - - -

14 - - - - - - -

15 - - - - - -

16 - - - - - -

17 - - - - - -

18 - - - - - -

19 - - - -

20 - - - -

21 - - - - - -

22 - - - - - -

23 - - - -

24 - - - -

25 - - - -

26 - - - -

27 -

28 -

umts induction training (general intorduction to hspa) v1.4

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