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HSDPA radio network planning
S-72.4210 PG Course in Radio Communications
Tommi Heikkilä (45444T)

21.2.2006

S-72.4210 PG Course in Radio Communications

1

Tommi Heikkilä

Outline

• Introduction
• HSDPA Deployment
• HSDPA Cell Planning
• Summary
• References
• Homework

21.2.2006

S-72.4210 PG Course in Radio Communications

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Tommi Heikkilä

Introduction
HSDPA(High Speed Downlink Packet Access)
• Described in 3GPP Release 5 specifications
– Enhances peak download data rate from current 384 kbps up to a theoretical
maximum downloading peak rate of 14.4 Mbps (10,7 Mbps with ¾ coding rate)
– Aimed for interactive and background services but streaming is also considered

• HSDPA brings benefits for both operators and end-users
– Higher data ratesfor end-users
– Larger and cost efficient capacity in the radio network
– Opportunity to deliver services - existing ones and new ones - at a lower cost of bit

• Requires investments to R99/R4 UMTS (WCDMA) network
– Affects radio network HW and SW, core network SW, and transmission network HW
– Can be deployed using small upgrades, not required for all BSs, RNCs
– Does not require acompletely new network structure
– Protecting the current investments made to the network

21.2.2006

S-72.4210 PG Course in Radio Communications

3

Tommi Heikkilä

Introduction
HSDPA Basics
• In order to reduce Round Trip Time (RTT) new features have been implemented in BS,
closer to the air interface
• Adaptive Modulation and Coding (AMC) Included in
Enhanced in
Excluded
–
–
–
–Depending on UE channel conditions (CQI)
QPSK, 16QAM
Coding rate (1/4 – 3/4)
Data rate adapted on 2 ms time basis

• Fast Retransmission
– Hybrid Automatic Repeat reQuest (HARQ)
– UE soft-combines data
– Reduced RTT

• Fast Packet Scheduling (PS)

HSDPA

HSDPA

AMC

Multi-code
operation

from
HSDPA

SHO
H-ARQ
Basic WCDMA
Technology

PC

TTI = 2 ms

Variable SFFast PS

– Scheduling of users on 2 ms time basis

• New radio channels included for HSDPA
– DL: HS-(P)DSCH, HS-SCCH
– UL: HS-DPCCH

• It is important to note that downlink HSDPA is a shared data channel
– End user throughput depends on the number of the other users on the same HSDPA cell
– Capacity planning and dimensioning of HSDPA is different to non-real time (NRT) DCH bearer21.2.2006

S-72.4210 PG Course in Radio Communications

4

Tommi Heikkilä

Introduction
Key Network Impacts and Investments of HSDPA

Reference [4]
21.2.2006

S-72.4210 PG Course in Radio Communications

5

Tommi Heikkilä

HSDPA Deployment
Process
Assessment of existing R99 network

Analysis of existing R99 network
performance

HSDPA performance target definition
andselection of deployment strategy

Configuration and capacity planning

Definition of parameter sets for HSDPA
capable cells
21.2.2006

• Hardware configuration audit used to verify suitability for HSDPA

• Field measurement surveys to evaluate HSDPA performance
• Monitor and analyse network performance and used resources
• Average used BS power for existing traffic
• Mixed or separatecarrier for HSDPA?
• BS processing card, RNC, and Iub usage
• Need for new elements?
• SHO areas and overhead analysis provide information for
planning HSDPA mobility and performance

• Several design and upgrade options for coverage and capacity
• Depends on strategy and traffic load in existing R99 network
• When, how and where HSDPA is deployed into the network
• Iub interface and BaseStation configurations based on
• Selected HSDPA deployment strategy
• Cell average throughput requirements
• For each Base Station
• Carrier configuration (single or multi?)
• HSDPA capable HW for traffic processing
• Iub capacity and ATM or IP configurations
• RNC
• Feature activation and management on cell basis
• HW processing capacity, interface capacity
• Parameter values should be...