Handover in Sony Ericsson P1, GSM to Umts | Sony Ericsson specification

White paper Sony Ericsson P1

•Continuity of active circuit switched services when moving within UMTS Radio Access Net- work, within GSM/GPRS and between UMTS Radio Access Network and GSM/GPRS cover- age areas.

√`çåíáåìáíó=çÑ=~ÅíáîÉ=~åÇ=é~ÅâÉí=ëïáíÅÜÉÇ=ëÉëJ

ëáçåë=ïÜÉå=ãçîáåÖ=ïáíÜáå=rjqp=o~Çáç=^ÅÅÉëë=

kÉíïçêâI=ïáíÜáå=dpjLdmop=~åÇ=ÄÉíïÉÉå=

rjqp=o~Çáç=^ÅÅÉëë=kÉíïçêâ=~åÇ=dpjLdmop=

ÅçîÉê~ÖÉ=~êÉ~ëK

General operational considerations

Mechanisms defined to support service continuity between different radio systems or radio access modes should effectively cope with a number of coverage scenarios:

•Limited coverage in a “sea” of coverage pro- vided by another radio system or radio access mode.

•Selective operation at a geographical boundary,

with extensive UMTS Radio Access Network coverage on one side, and extensive coverage from another radio system on the other side.

√dÉçÖê~éÜáÅ~ääó=ÅçäçÅ~íÉÇ=~êÉ~ë=çÑ=rjqp=o~Çáç=

^ÅÅÉëë=kÉíïçêâ=ÅçîÉê~ÖÉ=~åÇ=~åçíÜÉê=ê~Çáç=

ëóëíÉãK

Performance requirements

qÉãéçê~êó=ÇÉÖê~Ç~íáçå=çÑ=ëÉêîáÅÉ=Å~ìëÉÇ=Äó=

Ü~åÇçîÉê

During intra-UMTS Radio Access Network handover or handover from UMTS Radio Access Network to GSM/GPRS, degradation of service should be no greater than during intra-GSM/GPRS handover. The duration of the discontinuity experienced by packet switched and circuit switched real time services should be shorter than that in the handover of voice calls over GSM/ GPRS.

oÉèìáêÉãÉåíë=çå=ãìäíáéäÉ=ÄÉ~êÉê=ëÉêîáÅÉë=

Ü~åÇçîÉê=Ñêçã=rjqp=ê~Çáç=~ÅÅÉëë=åÉíïçêâ=íç= dpjLdmop

Consideration must be given to services that may involve multiple bearer services (and simultaneous sessions). The mapping between UMTS Radio Access Network bearer services and GSM/GPRS bearer services depends on many factors such as

data rate, delay constraints, error rate etc. In the event that certain UMTS Radio Access Network bearer services cannot be handed over to GSM/ GPRS, the handover of some of the bearers to maintain the service should not be precluded.

In the case where a user equipped with a dual mode terminal is in UMTS Radio Access Network coverage, and has multiple PDP contexts activated (for instance to support multimedia), then it is preferable to handover one PDP context, rather than dropping all of them.

As a first priority only the PDP contexts which have an associated QoS that can be supported by the GSM/GPRS should be candidates for handover.

If there are still multiple PDP contexts as “handover candidates”, then the operator should choose which PDP is maintained. When roaming, the serving network should make this decision. The operator may choose to either:

• Drop all of the PDP contexts.

√`ÜççëÉ=çåÉ=Ä~ëÉÇ=ìéçå=ÅêáíÉêá~=ëìÅÜ=~ë=Çìê~J

íáçåI=~ãçìåí=çÑ=íê~ÑÑáÅ=íê~åëÑÉêêÉÇI=ÉíÅK