A general setup for simulating a WCDMA cellular system has been developed to estimate the performance, in terms of both Signal-to-Interference Ratio (SIR) and error burst statistic. Here, the analysis has been focused on closed loop power control in order to characterize the performance as a function of the control delay and the step size in different conditions. The simulator takes into account a hexagonal geometry with spatially uniform user distribution and a propagation channel characterized by distance attenuation, log-normal slow fading, and Rayleigh fast fading. The system is based on a wideband CDMA radio interface with Rake receiver, convolutional coding with Viterbl decoding, and interleaving to counter-act burst error occurrences. A relationship between the power control loop and the Doppler frequency trend is underlined in the numerical investigation. In particular, a power control delay increase could be related to an "equivalent" Doppler frequency increase. Furthermore, t...
Some Results on Power Control in Wideband CDMA Cellular Networks
GIOVANARDI, Alessandra;MAZZINI, Gianluca;TRALLI, Velio;ZORZI, Michele
2000
Abstract
A general setup for simulating a WCDMA cellular system has been developed to estimate the performance, in terms of both Signal-to-Interference Ratio (SIR) and error burst statistic. Here, the analysis has been focused on closed loop power control in order to characterize the performance as a function of the control delay and the step size in different conditions. The simulator takes into account a hexagonal geometry with spatially uniform user distribution and a propagation channel characterized by distance attenuation, log-normal slow fading, and Rayleigh fast fading. The system is based on a wideband CDMA radio interface with Rake receiver, convolutional coding with Viterbl decoding, and interleaving to counter-act burst error occurrences. A relationship between the power control loop and the Doppler frequency trend is underlined in the numerical investigation. In particular, a power control delay increase could be related to an "equivalent" Doppler frequency increase. Furthermore, t...I documenti in SFERA sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
