無線通訊系統之能量效率頻寬分配機制之研究

A Study on Energy Efficient Bandwidth Allocation Schemes for Wireless Communication Systems

李哲豪(Che-hao Li)

指導教授 ： 黃永發

朝陽科技大學/資訊學院/資訊與通訊系/碩士(2014年)

摘要

本文基於正交分頻多工(Orthogonal Frequency Division Multiplexing,OFDM)系統，探討一個有效的「頻寬資源分配」之議題，並在有限的頻寬和能量效率(Energy Efficient)下，適當的分配頻寬方案。因此本論文中，在兩位使用者時，提出改善能量效率頻寬擴張(Improved Energy Efficient Bandwidth Expansion, IEEBE)分配法，在頻寬未到達滿負載之情況下可將剩餘頻寬作有效之分配，其能量效率比起相同頻寬擴張(Same Bandwidth Expansion, SBE)法要佳，由模擬結果可知，改善能量效率頻寬擴張法可提升能量效率。此外在多用戶環境下，本文基於IEEBE經過用戶排序後，提出配對(Pairs)、分群(Grouping)、二層分群(Two Layer Grouping)三種用戶配對法互相比較，由模擬結果可得知，二層分群可減少較多訊號功率(Signal Power)。
本論文最後，設計一模糊理論系統，由用戶需求頻寬與SNR推論出適當用戶之權重值，將頻寬分配給用戶，由模擬結果可知，我們提出模糊機制之能量效率頻寬擴張(Fuzzy of Energy Efficient Bandwidth Expansion,FEEBE)，可減少系統複雜度，而提升系統能量效率。

關鍵字

模糊機制之能量效率頻寬擴張 ； 改善能量效率頻寬擴張法 ； 正交分頻多工 ； 相同頻寬擴張法 ； 二層分群 ； 分群 ； 配對

並列摘要

In this thesis, the effective bandwidth expansion and allocated issues are investigated to improve the energy efficiency for the Orthogonal Frequency Division Multiplexing (OFDM) wireless communication systems. At first, an Improved Energy Efficient Bandwidth Expansion (IEEBE) method is proposed to save the energy consumption for two users with some avalible bandwidth. With an exghousted method, the energy efficient Bandwidth Expansion Factor (BEF) is found for proposed IEEBE. Thus the energy efficient performance of the IEEBE is superior to the simple Same Bandwidth Expansion (SBE). Moreover, when the number of user is more than two, three methods of pairs, grouping and two-layer grouping are proposed to effectively find the BEF for users based on IEEBE. Simulation results show that two-layer grouping outperforms the other two methods.
Finally, a Fuzzy Based Energy Efficient Bandwidth Expansion (FBEEBE) scheme is proposed to fast infer the BEFs for users based on fuzzy inference systems. The proposed fuzzy inference system can infer the BEFs from the two inputs of SNR and bandwidth requirement of users. Simulation results show that the proposed FBEEBE can improve the energy efficiency comparing to that of SBE scheme.

並列關鍵字

Fuzzy based energy efficient bandwidth expansion ； Energy efficiency ； Same bandwidth expansion ； Improved energy efficient bandwidth expansion ； Orthogonal frequency division multiplexing syste ； Fuzzy inference system ； Two-layer grouping

參考文獻

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