TR 21.910 identifies multi-mode User Equipments categories and describes the consequences on roaming capabilities and service availability (e.g. handover) of such multi-mode UEs while roaming in various regions implemented with various network configurations. The latter objective consists of case studies for each of the possible scenarios in reference to existing specifications. In these studies it has been important to make sure that no duplication of text has been made or that inconsistencies have been created between specifications. The initial version of this TR is limited to UEs implementing release 99 of the various modes roaming in regions implementing specifications up to and including release 99 of the associated specifications (e.g. a rel 99 multi-mode UE in a release 97 GSM network should be covered). In particular, the release 99 of this TR is focused on the type of UE that only can camp on one cell and be in active communication in only one mode at the same time. When the UE is in active communication in one mode it should be able to listen to the other radio access technologies and make e.g. measurements reports on this radio access technology and send them to the network, but no simultaneous active communication should be possible. This corresponds to a type 2 UE, as defined in the report in ch. 4. The scope of this TR is the type of terminal implemented with at least the following modes: UTRA FDD and/or TDD mode GSM mode The content of the scenarios could be used for other combinations of modes in a multi-mode UE. These are not considered in this version of this report. Regarding the GSM mode, it encompasses the capabilities offered by the GSM technical specifications, i.e. MSC services, GPRS, EDGE. This means that the sub-categories as offered by GSM should be considered e.g. GPRS only terminals, circuit switched only terminal, dual capability terminals. The present report is built on and references specifications/reports being produced in 3GPP or within other relevant foras e.g. ETSI SMG.
