Tham khảo tài liệu 'cellular networks positioning performance analysis reliability part 6', kỹ thuật - công nghệ, cơ khí - chế tạo máy phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | An Insight into the Use of Smart Antennas in Mobile Cellular Networks 139 Fig. 4. SDMA system with Duplicate at First Policy . From figures 5-6 it is possible to observe that the blocking probability is almost insensible to the residence time and to the call admission control policy. However from figures 7-8 it is possible to observe that call forced termination probability is very sensible to the mobility. As the mean residence time decreases call forced termination probability increases exponentially. This is because of the handoff probability also increases. Notice that when no Fig. 5. Blocking Probability for a system with Duplicate at Last Policy. No link unreliability is considered. 140 Cellular Networks - Positioning Performance Analysis Reliability Fig. 6. Blocking Probability for a system with Duplicate at First Policy . No link unreliability is considered. Fig. 7. Call Forced Termination Probability for a system with Duplicate at Last Policy. No link unreliability is considered. An Insight into the Use of Smart Antennas in Mobile Cellular Networks 141 Fig. 8. Call Forced Termination Probability for a system with Duplicate at First Policy. No link unreliability is considered. mobility is considered call forced termination is zero for all cases. This is because there are no causes of forced termination. Figures 7-8 show that the Duplicate at First policy is more sensible to the mobility. This is because in the scenario where there is more mobility there are also more handoff requests. The impact of radio environment in SDMA cellular systems Figures 9-12 show the impact of radio environment in blocking and call forced termination probabilities for different scenarios. Mean beam overlapping time E Xoi 4000 8000 No link unreliability . Evaluations presented in this section do not consider link unreliability due to the excessive co-channel interference. Figures 9-12 show how the link unreliability due to the co-channel interference brought within the cell .
