Radio network planning for UTRA TDD systems

A new methodology for UMTS Terrestrial Radio Access (UTRA) TDD bit energy-to-noise plus interference power spectral density ratio (PSD) or Eb/NtEb estimation in traffic loading conditions is discussed, the performance evaluation is demonstrated and the results are presented. The approach enables the signal to interference calculation by taking into account the traffic load in a circuit switched multimedia TDD CDMA network with randomly generated mobile users. Circuit switched radio links are considered only, with Monte Carlo generation of user location. It is shown that UTRA TDD is uplink limited, and that lower reuse patterns offer better QoS when the cells are partially loaded. The rules for resource planning are defined and the high level requirements for the development of network planning tools are determined. A further research on the performance of packet switched UTRA TDD radio links is required. A study was presented by Jeong and Jeon (see JSAC, vol.17, no.5, p.939-46), but only the mean value of the "packet" size (average activity) is used. When developing or using network planning tools, the trade off between speed and accuracy should taken into consideration. Indeed, the algorithms described here are also an approximation but its simple form enables quick processing. In general, any dedicated software will never describe accurately the events in the real network, but it will help in speeding up the network roll-out in the initial stages and in further growth as well as its optimisation.