近年來，智慧型行動裝置的普及化，使得每個人幾乎都有智慧型行動裝置，行動通訊服務也隨著這股潮流下蓬勃發展，而後因為行動通訊網路的成熟，促使更多物聯網(Internet of Thing, IoT)服務應用應運而生，像是智慧家庭、智慧工廠、車聯網(Vehicle-to-Everything, V2X),等都是現在熱門的議題與服務應用，然而快速成長的行動裝置數量，導致現有行動通訊網路框架下的基地台負載越來越重，使得行動通訊網路必須要更加提升，以提供更好的服務品質、有效率利用有限頻譜資源、擴展網路覆蓋率、裝置節能等多面向的改善與進步，提供用戶更優質的服務品質與體驗。
裝置間通訊技術(Device-to-Device Communication, D2D Communication)是其中一項改善現有網路的方式，可以達到多面向服務品質的改善，提供用戶複用有限的頻譜資源進行通訊，不需基地台轉送資料，減輕基地台的負載，且裝置間中繼通訊藉由中繼用戶的協助通道品質較差的用戶資料轉傳，解決基地台的邊緣用戶通道品質較差的問題。
本論文主要透過意願評估機制，找出意願度較佳的用戶擔任中繼用戶，不只考量中繼用戶本身的條件，並且中繼用戶幫助其他用戶之後，其他用戶幫助中繼的意願度將會提升，未來當中繼用戶需要被幫助時將會更容易被幫助，對於通道品質較差的用戶利用中繼轉送資料的方式，進而提升服務品質，對於系統、中繼用戶、通道品質較差的用戶都同時獲得好處，並且在分配頻譜資源時，藉由頻譜的複用使有限的頻譜資源能更有效率被利用，更利用循環排程演算法使得每個用戶都有機會進行傳輸。
由模擬結果顯示，本論文藉由中繼用戶幫助通道品質較差的用戶進行轉傳，提升頻譜資源的利用率，相同的頻譜資源下，能夠傳輸更多資訊量，提升整體系統的傳輸量。中繼選擇的演算法中考量到中繼的意願程度，如果是依照用戶的位置區分成中心用戶與邊緣用戶，邊緣用戶無法選擇到最好的中繼用戶進行轉傳，但是效能上與其他最好的方法相差不遠，如果是依照用戶的特質區分成熱情用戶與冷漠用戶，熱情用戶樂於幫助他人轉傳資料，也容易被他人幫助，因此效能上相較於冷漠用戶好。
關鍵字：裝置間通訊、裝置間中繼通訊、中繼選擇、社交關係、意願評估機制、循環排程演算法

In recent years, the popularity of smart mobile devices has led almost everyone to have smart mobile devices, making mobile communication services evolve with the trend, and because of the maturity of mobile communication networks, more Internet of Thing (IoT) applications are expected to be shipped, such as smart homes, smart factories, and Vehicle-to-Everything (V2X), are hot topics and applications, the number of fast-growing mobile devices has also led to an increase in load on the base stations of mobile communication networks. The mobile communication network must be upgraded to provide better service quality, efficient spectrum utilization, network coverage, and energy efficiency to provide users with better service quality and experience.
Device-to-Device (D2D) communication technology is one of the ways to improve the existing networks. It can achieve much quality improvement, provide users to reuse the limited spectrum resources, eliminate the need for base station to transfer data, reduce the load on the base station, and the relay-assisted D2D communication can better solve the problem of user of poor channel quality in base stations.
This thesis mainly uses the willingness assessment mechanism to identify users with better willingness to serve as relays. Not only the conditions of the relay users themselves, but also the relay users help other users, and it will be easier to be assisted when the relay users need to be helped in the future, thus encouraging the general users to use as relays. It uses relay for users with poor channel quality. The data approach improves service quality and benefits the users of systems, relays, and poor channels at the same time. When spectrum resources are allocated, limited spectrum resources can be used more efficiently. Using a cyclic scheduling algorithm gives each user an opportunity to transmit.
The simulation results show that this thesis helps users with poor channels to transmit and improve the utilization of spectrum resources. Under the same spectrum resources. Although the transmission amount can’t be greatly improved when considering the degree of willingness of the relay user, it can effectively consider the willingness of the relay user, and is not far from the performance of other best methods. In the relay selection algorithm, the willingness of the relay is considered. If the user is divided into the center user and the edge user according to the user's location, the edge user can’t select the best relay user to transfer, but the performance is the same as the other. If they are divided into enthusiastic users and indifferent users according to the characteristics of users, enthusiastic users are willing to help others to transfer data, and are also easily helped by others, so the performance is better than that of indifferent users.
Key words: Device-to-device Communication, Relay-assisted D2D Communication, Relay Selection, Social Relations, Willingness Assessment Mechanism, Round-robin Scheduling Algorithm

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