無線隨意網路中針對接收端阻隔問題提出適應性收端傳送協定之設計與分析

Abstract

分散式的無線網路環境中，因缺乏統籌管理無線資源的協調者， 因此媒體存取控制(MAC)協定之設計會是重要的議題。無線隨意網路 在吞吐量上的效能表現不彰，尤其接收端阻隔問題更進一步惡化無線 隨意網路的效能，因此本論文提出多重收端傳送機制(MRT)以及快速 網路配置向量截斷機制(FNT)來減緩接收端阻隔問題而不必額外再採 用控制通道以及傳輸天線。為了進一步提升MRT 以及FNT 之系統效能，本論文尚提出適應性收端傳送協定(ART)，以及可支援動態收端數目調整之演算法(ART-DA)。爾後，本研究針對ART 通訊協定建立數學模型分析其效能，透過電腦模擬亦驗證了分析結果的準確性。此外，模擬結果同時也與已存在對抗接收端阻隔問題的通訊協定進行比較，顯示本研究提出的通訊協定以及搭配的演算法能更有效率的解決接收端阻隔問題，提升整體無線隨意網路的系統吞吐量。

Due to the lack of a centralized coordinator for wireless resource allocation, the design of medium access control (MAC) protocols is considered crucial for throughput enhancement in the wireless ad-hoc networks. The receiver blocking problem, which has not been studied in most of the MAC protocol design, can lead to severe degradation on the throughput performance. In this paper, the multiple receiver transmission (MRT) and the fast NAV truncation (FNT) mechanisms are proposed to alleviate the receiver blocking problem without the adoption of additional control channels. The adaptive receiver transmission (ART) scheme is proposed to further enhance the system throughput with dynamic adjustment of the selected receivers. Analytical model is also derived to validate the effectiveness of the proposed ART protocol. Simulations are performed to evaluate and compare the proposed three protocols with existing MAC schemes. It can be observed that the proposed ART protocol outperforms the other schemes by both alleviating the receiver blocking problem and enhancing the system throughput for the wireless multi-hop ad-hoc networks.