 measured/analysed and optimised. These parameters can be divided into various groups based on the functions they affect the most. These groups may include parameters affecting handover control, packet scheduling, power control, call admission control, etc. Handover Optimisation Soft handover gain is one of the parameters in the link budget calculations. SHO gives some protection against both slow and fast fading. With regard to slow fading, because of the Table 7.7 PS service requirements and drive test results Conditions Required Performance Downlink Downlink Uplink 64kb/s Airlink capacity BLER Data session Data session Session Average Peak Data rate DPCH.Eb/ DPCH_Eb/ [kb/s per (uplink and drop rate activation activation Throughput (uplink [kb/s] No [dB] No [dB] carrier/sector] downlink) 1 drop/N hours failure rate delay time 17 and downlink) 18 R1.5.2 N> 15 hours >50 kb/s R1.5.2 > 3.5 N> 15 hours > 101 kb/s R1.5.2 >5.0 > 3.5 N> 15 hours > 303 kb/s Drive Test Results Summary 6.34% No drop/ 1.41% 89.40% 57.06kb/s (UL) 15 hours 341.36kb/s (DL) Sample Size 12320 14711 (UL) 1194 (DL) WCDMA RADIO NETWORK OPTIMISATION lack of correlation between base stations, a mobile is able to select a better base station (based on the measurements analysed in the RNC). With regard to fast fading, through the effect of macro diversity combining, the required Eb/No is reduced. Soft handovers also induce overhead in capacity calculations, as at a given time a mobile is connected to more than one cell, thereby increasing the capacity requirements. Thus, both the overheads and the gain should be optimised. The idea behind optimising the overheads is to save on downlink capacity. A typical value of the SHO overhead is 30-40%. SHO gain, on the other hand, can be estimated by using parameters such as DCR, CSR (call success rate), transmit and receive powers. For capacity and coverage optimisation, it is very important to optimise the handover control feature in these networks. One important parameter to mention is the transmitting power 