在本文中，我們探討在第五代行動網路整合傳輸及回傳網路(Integrated Access
and Backhaul) 中下行傳輸的資源分配問題。為了提供更高的系統流量，我們採用多
連結傳輸來增加傳輸彈性。基地台透過毫米波傳輸資料，然而毫米波容易因為堵塞
而傳輸失敗，因此我們提出的模型會考慮該連結的堵塞機率。若系統決定服務使用
者，則基地台必須分配足夠的資源塊，使資料能夠經由多跳路由傳至使用者，目標
是最大化系統流量我們將問題轉換為分層多背包問題，並提出一個三階段的演算
法。首先，給定使用者需求，我們通過考慮通道品質以及堵塞機率決定要服務的使
用者。接下來，由於多連結的使用者資料可以透過多個已連結的基地台傳輸，我們
需要決定資料如何分流。此兩步驟會不斷執行至沒有額外的資源塊能夠分配。最後
我們收回分配給未完全服務的使用者的資源塊，並使用這些資源塊服務更多使用
者。模擬結果顯示，我們所提出的演算法在系統流量方面優於候選演算法。

This work examines the resource allocation for downlink transmission in the Integrated Access and Backhaul (IAB) networks with mmWave. To increase system throughput, we adopt multi-connectivity to increase transmission flexibility. Since mmWave is vulnerable to blockage, the transmission can fail if the link is blocked. Therefore, we consider the blockage probability of the link in our model. In our system, downlink traffic is transmitted hop-by-hop to the end user equipment (UE). Each UE has a service request, and the base station (BS) has to decide which UEs to satisfy. If a BS intends to serve a UE, it will reserve its physical resource blocks (PRBs) for downlink traffic. Our objective is to maximize the total throughput of the system. We modeled the problem as a hierarchical multiple-knapsack problem and proposed a three-phase algorithm. First, we decide the UEs served by the BS, considering channel quality and blockage probability. Next, we split the traffic of the multi-connected UEs to their associated BSs. These two steps will run iteratively until no PRBs can be allocated to UEs. Finally, we will check if the request of each UE is satisfied. If not, the BS will take back the allocated PRBs and try to serve other UEs with these PRBs. The simulation results show that the proposed algorithm outperforms the candidate algorithms in total throughput.

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