Call Flow

A comparison between the call flow in GSM and UMTS

Handover/Clear

Call to a MS

Paging

Call from a MS

ImmediateAssignment

Assignment / Change of

Mode

Supervision

on CCCH/PCH

on CCCH/AGCH

Immediate assignment of SDCCH

on SDCCH

on TCH

Assignment of TCH

on RACH

Locating

Initiations

Filtering

Urgency

Basic Ranking

Aux RadioNetwork

Function Eval(HCS)

Organizing List

Sending List

Allocation Reply

MEASUREMENTS

• Immediate

Assignmenton TCH

• ACLC

• ASSOC

• AW• CL

S• DH

RA

Handover• Inter

cell/BSC• Intra

cell/BSC• OL/UL• Bad

Quality• Urgency• HCS

Channel Administration

(SDDCH Perform.)

(Random Access)

(Assignment Fail.)

(Traffic Erlangs)

(Call Quality)

(Handover Perf.)

(Dropped Calls)

(Available TCH)

(Paging Perf.)

GSM Call Flow

Soft/SofterHandover/

Clear

Call to a MS

Paging

Call from a MS

RRC Connection

RABAssignment

Supervision

on PICH/SCCPCH

on FACH/ SCCPCH Predefined Signaling

RAB Selected

on FACH/SCCPCH

on DPDCH

Assignment of DPDCH

on RACH

ActivateAlgorithms

Power Ctrl.

Code Ctrl.

Admission Ctrl.

RAB Selection

MEASUREMENTS

• Directed Retry

• Load Sharing

Soft Handover• Inter

cell/BSC• Intra

cell/BSC• OL/UL• Bad

Quality• Urgency• HCS

Inner Loop/Outer Loop Power Control

(RRC Connect. Perform.)

(Random Access)

(RAB Establish. Fail.)

(Traffic Erlangs)

(Call Quality)

(Handover Perf.)

(Dropped Calls)

(Available TCH)

(Paging Perf.)

UMTS Call Flow

Open LoopPower Control

(Throughput)

Open Loop on Access Channel