在第五代行動通訊所使用的毫米波頻段中，由於毫米波的穿透性比較薄弱，傳送 的訊號很容易被環境所吸收，因此遮蔽效應在第五代行動通訊中是個嚴重的問題。 在室內場景中，由於環境與室外相比較為複雜造成較高的散射，因此在室內中遮蔽 效應會更加的明顯。本碩論從載波頻率、基地台高度、波束寬度與遮蔽物密度等四 個因素來分析不同因素與室內的遮蔽效應的關係。藉由分析上述四種不同的因素使室內的遮蔽效應可以有更深入的探討。目前用來解決遮蔽效應的方法為波束管理，當正在傳送的波束對被遮蔽後，藉由波束管理重新搜尋遮蔽後此基地台與手機中最好的波束對，並進行切換。然而波束管理會受限於能對於正在連結的基地台下的波束進行切換，而這樣的切換並不能有效的補回遮蔽效應造成的能量衰減。這篇碩論使用了聯合傳輸來解決毫米波頻段中的遮蔽效應，聯合傳輸為協調多點收發的其中 一個方法，使多個基地台可以同時傳送訊號給同一個手機。此碩論考量了現行通訊系統的限制，傳送端一個時間單元內只能啟用一個傳送單元，為了克服此限制，此碩論提出了排程方法來解決，使所有的手機無論是否受遮蔽效應的影響皆能被基地台服務。這篇碩論所提出的排程方法是模擬於系統層級模擬器中並且遵循第三代合作夥伴計劃的規範，使室內場景的遮蔽效應可以更貼近真實的世界，並且呈現了排程後聯合傳輸對系統的效益。

Blockage is a serious issue in 5G New Radio (NR) operating on the Millimeter Wave (mmWave) band. Due to directional transmission and the severe penetration loss of mmWave, transmission is more likely blocked by the surrounding environment. Particularly, mmWave links in the indoor scenario with rich scatters are expected to be more vulnerable to the blockage effect. In this work, we analyse the blockage effect caused by different factors including carrier frequency, Base Station (BS) height, beamwidth and the density of blockers. With the factors described above, the blockage effect in the indoor scenario can be evaluated more thoroughly. To alleviate the blockage effect, beam management has been proposed to allow beam switching but it is restricted to the beams of the serving BS when the transmission beam pair link (BPL) is blocked. Since the initial BPL is the strongest among all the available ones, it may not be always effective to recover the power loss of a blocked BPL by changing the existing beam management scheme. In this work, Joint Transmission (JT) is considered as a potential means to solve the blockage effect in mmWave. As a branch of Coordinated Multi-point (CoMP) technique, JT allows a User Equipment (UE) being served by multiple BSs simultaneously. In practice, the transmission side can only activate one transceiver units (TXRU) with one beam direction per time unit. In order to serve the UE who encounters blockage and the UE without blockage, we design a scheduling method by taking the physical constraint of future BS into account. The proposed scheduling scheme is implemented in a system-level simulator that fully complies with the 3GPP specifications. We evaluate the impact of blockage effect in an realistic indoor environment and also the performance of the proposed scheduling scheme based on JT.

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