oth FDD and TDD modes of radio interface. UTRA/E-UTRA network in its two It is also responsible for handling physical layer related UE modes, FDD and TDD. capabilities and physical layer related parameters used in UE test developed in the RAN working group. RAN WG2 This group is in charge of the radio interface architecture and protocols, the specification of the radio resource control protocol, the strategies of radio resource management, and the services provided by the physical layer to the upper layers. RAN WG3 This group is responsible for the overall UTRAN/E-UTRAN architecture, the specification of inter-base station protocols, and the interface between the mobile station and base station. RAN WG4 This group works on the radio aspects of UTRAN/E-UTRAN It performs simulations of diverse radio system scenarios and derives the minimum requirements for transmission and reception parameters. Once these requirements are set, the group defines the test procedures that will be used to verify them (only for base stations). (Continued) Table 1-5 3GPP Organization iii Continued RAN WG5 This group works on the specification of conformance testing at the radio interface for the user equipment. The test specifications are based on the requirements defined by other groups, such as RAN WG4 for the radio test cases, and RAN WG2 and CT WG1 for the signaling and protocols test cases. Service and System Aspects (SA) SA WG1 (Services) The Service and System Aspects This group works on the services and features for 3G. The group is responsible for the overall group sets high-level requirements for the overall system and architecture and service capabilities provides this in a Stage 1 description in the form of of systems based on 3GPP specifications and reports. specifications, and has SA WG2 (Architecture) a responsibility for inter-group This group is in charge of developing Stage 2 of the 3GPP coordination. network, and identifies the main functions and entities of the network, how these entities are linked to each other, and