marizes key (selected) requirements identified for the UTRA con- cept from [18]: Table 1.2 UTRA High Level Requirements Key requirements Description Bearer capabilities Maximum user bit rates Rural Outdoor: at least 144 kbit/s (goal to achieve 384 kbit/s), maximum speed: 500 km/h Suburban Outdoor6 at least 384 kbps (goal to achieve 512 kbit/s), maximum speed: 120 km/h Indoor/Low range outdoor1: at least 2 Mbps, maximum speed: 10 The UTRA definition should allow evolution towards higher bit rates Flexibility Negotiation of bearer service attributes (bearer type, bit rate, de- lay, BER, etc.) Parallel bearer services (service mix), real-/non-real-time communication modes, etc. Circuit and packet oriented bearers Supports scheduling (and pre-emption) of bearers (including control bearers) within priority Adaptability of link to quality, traffic and network load, as well as radio conditions. Wide range of bit rates should be supported with sufficient granu- larity The specified bit rate will be available throughout the operator's service area, with the possibility of large cells. The specified bit rate will be available with complete coverage of a suburban or urban area, using microcells or smaller macrocells. The specified bit rate will be available indoors and localised coverage outdoors. Evolving Mobile Networks Variable bit rate real time capabilities should be provided Bearer services appropriate for speech shall be provided Handover Provide seamless (to user) handover between cells of one opera- The UTRA should not prevent seamless HO between different operators or access networks Efficient handover between UMTS and 2nd generation systems, e.g. GSM, should be possible Operational requirements Compatibility with ser- ATM bearer services vices provided by pre- GSM services sent core transport net- works IP (internet protocol) based services B/N-ISDN services Radio access network If radio resource planning is required, automatic planning shall be planning supported Public network operators It shall be possible to 