Performance Evaluation of Considering D2D Relay User’s Willingness in LTE-A

• Main Authors: Kai-Cheng Ji, 紀凱程
• Other Authors: Bih-Hwang Lee
• Format: Others
• Language: zh-TW
• Published: 2018
• Online Access: http://ndltd.ncl.edu.tw/handle/vgk7kp

碩士 === 國立臺灣科技大學 === 電機工程系 === 106 === 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