在基於正交分頻多工技術的系統裡，細胞間干擾是相當重要之研究議題。此干擾會影響基地台和用戶端設備通訊之訊號品質，當用戶端設備在細胞邊緣時更為嚴重。為了改善干擾的問題，3GPP在進階長程演進系統(LTE-A)裡定義了高干擾指(HII)和過載指示(OI)來協調上行傳輸的細胞間干擾。高干擾指示提供負向回饋來避免不當的資源分配。過載指示用來通知基地台在相鄰細胞有干擾過載的事件發生。
在本論文中，我們分析以高干擾指示和過載指示為基礎的現有方法的效能，並提出藉由引進正向回饋的指示，搭配原有的高干擾指示和過載指示之方法，確保系統效能的提升。模擬結果顯示，我們的方法可有效提升細胞邊緣使用者及所有使用者的平均上行吞吐量。

In Orthogonal Frequency Division Multiplex based system, inter-cell interference is an important issue, which impacts signal quality between evolved NodeBs and user equipments (UEs), especially for UEs at cell edge. In order to relieve this issue for uplink in Long Term Evolution-Advanced system, Third Generation Partnership Project defines high interference indicator (HII) and overload indicator (OI) to coordinate interference. HII provides negative feedback to prevent inappropriate resource allocation. OI is used to notify neighboring cells of an interference overload event.
In this thesis, we investigate the performance of existing schemes based on HII and OI. Then we propose a scheme with positive feedback by introducing a new indicator to work with HII and OI to ensure improvement of system performance. Simulation results show that our scheme can effectively enhance average uplink throughput of cell edge UEs as well as the total uplink throughput.

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