As the LTE network infrastructure is currently in development, this paper provides an objective assessment of the VoIP performances for an LTE cell deployed in a 3D modeled urban area. Fundamental E-UTRAN technologies have been tested in the LTE cell used at full capacity for the 1.4MHz and 5MHz channel bandwidths. The VoLTE performance improvements are evaluated in terms of QoS and QoE parameters. The simulation results provide useful insights for the operators regarding an efficient LTE network planning.