tailieunhanh - Radio network planning and optimisation for umts 2nd edition phần 10

Yêu cầu này được thúc đẩy bởi một thực tế rằng việc triển khai các ăng-ten nhiều trong các thiết bị đầu cuối di động hoặc BS để hỗ trợ các kỹ thuật MIMO là không đơn giản do mối quan tâm của chi phí, phức tạp và tác động thị giác. Điều này là đặc biệt đúng với các thiết bị đầu cuối di động ngày nay | Advanced Analysis Methods and Radio Access Network Autotuning 561 Table Micro 46-cell scenario results for circuit switched speech and packet switched traffic. Measure Parameter setting PtxTarget 33 dBm fixed offset PtxTarget 33 dBm DL link maxima tuned PtxTarget dBm fixed offset dB PtxTarget dBm DL link maxima tuned Number of ended RT CS calls 14472 13696 15057 14674 Probability of degraded RT CS BLER RT CS blocking probability 13 RT CS throughput kbps cell 500 473 520 507 NRT PS throughput kbps cell 264 255 542 494 DL total throughput kbps cell 764 728 1063 1001 The conclusion drawn from the results is that the autotuning of cell-based downlink link maxima and load targets improves significantly the system performance as measured with throughput particularly in comparison with cautious or incorrect parameter settings. Therefore the feature is a promising candidate for implementation into the NMS. Capacity Optimisation and Traffic Balancing In the following sections some mechanisms to share resources between circuit switched and packet switched traffic or between cells is discussed. A similar logic can be applied to GPRS as demonstrated in Chapter 10. The traffic control mechanism between systems inter-system handover is introduced in Chapter 4. Autotuning of P-CPICH Power The primary objective of the methods presented in this section is to minimise the usage of power resources for the P-CPICH while ensuring good enough P-CPICH coverage. This is even more important if the power levels of all other common channels are set with respect to P-CPICH power - . higher amounts of power resources can be saved and more traffic served. The original work is presented in 36 . Method for Autotuning P-CPICH defines the power of the P-CPICH in the cell. Increasing or decreasing the pilot power makes the cell larger or smaller. Thus the tuning of pilot powers can be applied to balance cell load among .