第五代(5G)無線通訊系統中， 使用毫米波之裝置間通訊是一項極具前
景及發展潛力的技術；其能夠以較大的頻寬及傳輸指向性大幅度的提升端對端之間的通道容量。然而，毫米波眾所皆知的高路徑衰退及阻斷問題嚴重限制了裝置間通訊的可達性。因此，中繼傳輸便成為了有效克服毫米波傳輸技術難題的必要解決方案。在本篇論文中，我們致力於提升全雙工中繼協助之毫米波裝置間通訊系統的能源效益。為了達到此目標，我們首先採用非線性分式規劃的迭代功率配置演算法進行能源效益的最佳化。再者，我們進一步提出了瓶頸效應消除之功率調配方法以期在維持端對端間通道容量的情況之下減少無謂的傳輸功率。結合迭代功率配置演算法、瓶頸效應消除之功率調配方法與適當的配對演算法，我們提出了能源效益中繼之瓶頸效應消除功率調配演算法。經由模擬結果之驗證，本篇論文所提出之方法確能有效提升全雙工中繼協助之毫米波裝置間通訊系統的能源效益。

In the fifth-generation (5G) of the wireless communication systems, the millimeter wave (mmWave) based device-to-device (D2D) communication is a promising technique to boost the end-to-end capacity. However, the well-known blockage and high path loss problems of the mmWave severely restrict the reachability of the D2D communication. Therefore, the relaying transmission scheme becomes a necessary component to complete the puzzle of the technologies for 5G. In this thesis, we aim to boost the energy efficiency (EE) of the full duplex relay-aided mmWave D2D communications. To achieve this goal, the nonlinear fractional programming (NFP) based iterative power allocation (IPA) algorithm is firstly developed to optimize the EE. Then, on top of it, the bottle-neck effect elimination power (BEEP) adjusting method is proposed to further reduce the transmission power while maintaining the end-to-end capacity. By combining these techniques with properly designed matching algorithm, we propose the EE relaying with BEEP (BEEPER) algorithm. Via the simulation results, the superior performance of the BEEPER algorithm is verified.

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