大多數現有或開發中的IoT通信標準是基於以下假設：IoT服務僅需要低數據速率傳輸，因此限制了其通訊的頻段，使用較小，和瑣碎的資源來提服務像是Narrow-band 頻道。此假設明顯無法負荷具有突發流量，關鍵任務和低延遲要求的IoT服務。 在本文中，利用物聯網網絡中的空閒設備，通過多個物聯網設備的轉發傳輸，提高了傳輸數據效率。這種方法虛擬擴展了IoT使用的Narrow-band 頻寬，利用載波聚合，從而實現物聯網網絡中緊急任務的低延遲服務。我們提出任務平衡方法（TBM）和第一鏈路降序（FDO）來決定物聯網裝置其轉送的順序和其各裝置傳送資料的數據量。我們證明了可以在polynomial time中導出最小化上傳延遲的最優轉送配置，且提出了另一種情況，需要選擇轉送裝置的問題，提出了Greedy algorithm，並證明此演算法至少近似於最佳解的1/2之效能。最後，模擬結果表明，與傳統方法相比，所提出的方法可以將傳輸任務的延遲降低76％

Most existing or developing IoT communication standards are based on the assumption that IoT services only require low data rate transmission and therefore can be supported by limited resources such as narrow-band channels. This assumption rules out those IoT services with burst traffic, critical tasks, and low latency requirements. In this
aper, we propose to utilize idle devices in IoT networks to boost the transmission data rate for critical tasks through multiple concurrent transmissions. This approach virtually expands the existing narrow-band IoT protocols to support channel aggregation in order to realize low latency services for critical tasks in IoT networks.
We propose task-balance method (TBM) and first-link descending order (FDO) to determine the relay order and data partition in a given relay set. We theoretically prove that the optimal relay configuration that minimizes the uploading latency can be derived in polynomial time.
We establish the hardness of the relay selection
problem and propose a greedy algorithm to approximate the optimal solution within a $1/2$ performance lower bound. The simulation results shows that the proposed approach can reduce the latency of critical tasks up to 76\% comparing with traditional approaches.

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