s. The NMS should have the capability to handle the various aspects of the WCDMA radio network, which is in a multi-technology and multi-vendor environment. 7.7.3 Coverage, Capacity and Quality Enhancements Coverage Enhancements Coverage is directly related to link performance. An increase in coverage will demand an increase in the average TX power of a base station in the downlink direction. If the system capacity is downlink-limited, then an increase in coverage will lead to a decrease in capacity. If the system is uplink-limited, then the capacity is not affected. Thus, link performance increase is directly related to the increase in coverage. There are many ways to improve the coverage. We have already seen the main parameters affecting link performance. Parameters such as block error rate, Eb/No, power control headroom, etc., directly affect the power budget and hence the coverage. Uplink coverage can be improved by decreasing the interference margin or by reducing the base station noise figure, or even by increasing the antenna gain. However, the processing gain and Eb/No are the two major values affecting coverage. So a reduction in Eb/No increases the coverage of the network. This is because, for a lower Eg/No, less power is required for the same performance, SO a bigger area can be COV- ered. The performance of Eb/No is dependent on a number of factors such as the bit rates, channel accuracy, SIR algorithms, etc. Uplink coverage becomes an issue at higher bit rates in WCDMA networks, SO accurate traffic distribution will play a major role in coverage improvement. However, if the bit rate of the uplink direction can be reduced, the coverage Table 7.6 Drive test result summary for Video Requirements Conditions Required Performance DPCH_Eb/ DPCH_El Loading Drop Call Call setup Call set-up delay8 No (downlink) No (uplink) (downlink) Rate 6 failure rate7 95th percentile9 Mobile Mobile Mobile Mobile originated terminated originated terminated R1.5.2 > 6.5 <3.5% <2.5% <2.5% <5 sec <5 sec Drive test Results Summ