摘要(英) |
Customer complaints usually come from cell edge users. For 2G/3G complaints, one of the most commonly used improvement methods by on-site personnel is to adjust the correlation power of the covered area. This is relatively similar to the technologies within LTE, which are CRE (cell range expansion) and SFR (soft frequency reuse). This thesis is an in-depth study of the usability of pico cell SFR and also performs an integrated study of both the SFR and CRE technologies, analyzing their influences, restrictions, and interrelations for the down links and differences between urban areas and rural areas. And finally, conclude a simple adjustment method and recommended value for on-site personnel to use as a reference to improve the throughput of cell edge users.
Our analysis and simulation results indicated that the adjusted value of both SFR and CRE should not be too large. Also, although SFR is able to improve the throughput of cell edge users, it’s usually a trade-off with the average throughput. However, at rural areas where there are better pico cell channel qualities, a suitable adjusted value of pico cell SFR was able to improve the throughput for 5% of pico cell users by 18% and improve the average throughput by 2%. The throughput of 5% of the users and the average throughput in the overall system were able to be increased by almost 2%. In addition, for pico cell CRE problems that caused the user to get blocked or dropped, when used with pico cell SFR, there was an approximately 1~4% improvement. As for the simple adjustment method that we concluded, simulation results showed that it was usable. |
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