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HSUPA (E-DCH) introduction & parameters Jens Kuhr – Network Engineering COO RA RD SA NE

For internal use 1 © Noki Nokia a Siem Siemen ens s Netw Networ orks ks

HSUP HSUPA A / JKuh JKuhrr / Sept Septem embe berr 2007 2007

Outline HSUPA Channels HSUPA Scheduling mechanism HARQ Process HSUPA RAB-Handling HSUPA Mobility aspects HSUPA Admission Control HSUPA Congestion Control HSUPA OLPC UE categories + E-TFCI selection



Outline HSUPA (High Speed Speed Uplink Packet Packet Access) is used to improve improve uplink uplink data rates in • HSUPA WCDMA networks. using enhanced techniques (e.g. • It is reusing the available infrastructure by using adaptive coding) thus allowing to make better use of the available ressources. peak rates and increases coverage coverage for high datarates • Provides higher peak WCDMA network more interesting interesting • Shorter round trip times (RTT) make the HSPA WCDMA for real time applications like online gaming dedicated transport channel in uplink (E-DCH), (E-DCH), unlike • HSUPA uses an enhanced dedicated HSDPA, where only one downlink channel is shared among the users. HSUPA is specified specified for data rates of up to 5.76 Mbps • HSUPA



Comparison between HSUPA and HSDPA Similarities with HSDPA: - NodeB controlled scheduling - HARQ process - Shorter TTI than classic DCH (10ms, 2ms (HSDPA 2ms TTI only)) - Fast link adaptation techniques

Differences to HSDPA: - dedicated channel (E-DCH) instead of shared channel in HSDPA - no adaptive modulation - full mobility (soft handover possible)

Like HSDPA, HSUPA is based on scheduling in the NodeB, link adaptation and HARQ process For internal use 4 © Noki Nokia a Siem Siemen ens s Netw Networ orks ks


In UMR and RAS currently only 10ms TTI implemented.

HSUPA Princ Principles iples

1-4 Code Multi-Code transmission

TTI TTI = 2 / 10 10 ms

Hybrid ARQ with incr. redundancy

Fast Power Control

Benefit Higher Uplink Peak rates: 2-5.76 Mbps Higher Capacity: +50-100% Reduced Latency: ~50-75 ms



Scheduling

HSPA Scheduling

- A H C D - B H C D - C H C D

Node B Rel. 99

Dedicated pipe for every UE

i n g l u d h e c S

- A

B H C D E H C D E

C , B , A

Node B w/ HSDPA HSDPA 3GPP Rel. 5

Fast pipe is shared among UEs For internal use 6 © Noki Nokia a Siem Siemen ens s Netw Networ orks ks

H C D E


- C

Node B w/ HSUPA 3GPP Rel. 6

Dedicated pipe for every UE in UL Pipe (codes and grants) changing with time E-DCH scheduling

HSUPA Channels - Uplink



Channel mappin mapping g introduced as a new transport transport channel • For HSUPA, the E-DCH is introduced for carrying user data on the uplink.

• On physical layer, this translates translates into 2 new uplink uplink channels.

E-DCH

E-DPDCH



Transport channel

E-DPCCH

Physical channel

E-DCH: Enhanced Dedicated Channel Dedicated uplink transport channel • Dedicated uplink

• Dedicated to 1 UE • 2ms or 10ms TTI • Controlled by NodeB scheduling process • Holds one or more dedicated physical data channels (E-DPDCH)



E-DPDCH: E-DCH Dedicated Physical Data Channel uplink physical channel • Dedicated uplink 10ms TTI TTI • 2ms or 10ms

• Controlled by NodeB NodeB scheduling process • The E-DPDCH E-DPDCH is used by E-DCH for the transmissi transmission on of user data and Scheduling information (SI) E-DPDCH per radio link link for higher throughpu throughputt • Up to 4 E-DPDCH handover • Supports soft handover



E-DPCCH: E-DCH Dedicated Physical Control Channel Dedicated uplink physical channel. • Dedicated uplink

• Transmits control information about the E-DPDCH transmission: – E-TFCI (Transport block format combination indicator) – RSN (Retransmission sequence number) for the HARQ process – Happy Bit

• There is at most one E-DPCCH on each radio link. • Carries the „Happy Bit“



With the Happy Bit the UE tells the NodeB scheduler every 2ms whether the ressource allocation was sufficient to transmit all data or not.

E-DPDCH & E-DPCCH

E - -D P D D P C D H C H ( u us s

e er r d d a at t a a, S I I) )

E - -D P D C ( c P C co n C H o nt t r C H ro l l d o d a at t a a, e .g H H a ap p p py B y B i it t ) )



E-DCH serving cell • E-DCH and HSDPA serving link is always assigned by RNC to the same cell (Best Cell) based on UE measurements.

NodeB 1

Non Serving RLS (1 RL)

NodeB 2

Serving RLS Serving E-DCH Cell

same RG information information (per RLS)

RG information per RL HICH information per RLS

same HICH information information (per RLS)

E-HICH E-AGCH E-RGCH



HSUPA Channels - Downlink



E-AGCH: E-DCH Absolute Grant Channel • Common downlink physical channel channel • Time-multiplexed shared channel with explicit UE addressing addressing using ERNTI

• On the E-AGCH, E-AGCH, the NodeB NodeB tells the UE an absolute power absolute power level (alsolute grant, AG) AG ) for the E-DPDCH relative the DPCCH (precise value, thus also more information to be transmitted)

• In soft handover handover state, state, the E-AGCH E-AGCH is transmitted by the serving E-DCH cell only

• Uses SF256 E - - AG C C H H ( a ab b

s so ol l u t t e u p e p w wr r ) )

E - -R R G GC CH ( H u u p p

,d o o w wn , h o o l ld ) d )

E - -D P D D P C D H C H

( u us e r r d d at a) For internal use 15 © Noki Nokia a Siem Siemen ens s Netw Networ orks ks


d ) l d w n, h o o d ( C H

E - R G

D C H E - D P t a a )

d a ( u s e r

E-AGCH: primary & secondary absolute grant allocated (primary (primary & secondary secondary E-RNTI) E-RNTI) that it needs • An UE can get two E-RNTIs allocated to listen to on the E-AGCH. follows the AG transmitted transmitted for the primary primary E-RNTI (primary (primary AG). • The UE always follows – It can be commanded commanded to follow the AG transmitted transmitted for the secondary secondary E-RNTI E-RNTI as well.

mechanism can be used to control a group of UEs together (which (which will then • This mechanism all have the same secondary E-RNTI assigned) – E.g. group of “always on” UEs, that only occasionally send data – They will then be controlled controlled as a group by a limited “secondary “secondary AG” AG” – If one of that UE that UE have needs to send more uplink data , it will then get an primary an primary grant assigned grant assigned via the primary R-RNTI.

– As soon the primary primary grant is not needed anymore, anymore, the UE can be switched to secondary grant again.



E-AGCH power settings in RNC Name

Q3-Name

Shortname

Longname

LMT-Name

Type

Range

Unit

R/ W

Default

E-AGCH Power Offset

sbs3gRanAg chPwrOffset

AGCHPWR OFF

agchPower Offset

po_agch

Integer

0..255 (0..2.55)

LMT: dB

RW

128 (RC)

Mapping to -32..+31.75 by step of 0.25 Indicates the Power offset relative to the pilot bits on the DL DPCCH

Example of command execution (hmi): cre hsupa cellid=1 hsupa cellid=1 nodebid=1 no_rgch_hich=4 po_agch=1.25 no_rgch_hich=4 po_agch=1.25 po_hich=1.25 po_hich=1.25 po_rgch=1.25 pr_edch=30



RC: 0.01*d B

1.28 (LMT)

Scheduler in NodeB, O&M parameter description Name

Range

Unit

R/W

Default

hsupaPowerOffsetEAGCH

Range: -32..31.75

dB

V

76 (-13 dB)

Step: 0.25 Mapped in database to range 0..255 Power offset of E-AGCH (secondary (secondary E-RNTI) (configurable only at CHC start-up start-up time). Relative to CPICH power. Vendor power. Vendor parameter: not recommended to be changed by the operator. Name

Range

Unit

R/ W

Default

maxSecondAbsGrant

Value range: [0…31]

-

R

5

5 ~ 32 kbps 9 ~ 128 kbps 9 shall not be exeeded

index value of 3GPP 25.212, section4.10.1A.1, table 16B Upper limit to the Secondary AG that may be assigned to all UEs in a radio cell. When doing RTT ("ping") measurements, note that the default value of 5 will have negative impacts on the RTT, as it does not allow a ping of 32 bytes to be sent within one MAC-e PDU: 2 PDUs are needed. To have an optimal RTT, either ensure that you have a Primary Grant active or set this value to a minimum of 7. Name maxNumberPrimaryGrantUe

Range 0..255

Unit

R/W

Default

-

V

4

Example of command execution (xml):

Maximum number of simultaneous UEs with Primary_Grant_Available = “True” Vendor parameter: not recommended to be changed by the operator.

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