無線隨意網路上通道與功率參數整合研究

Abstract

在傳輸媒介共享的無線網路研究中，提出許多的傳輸功率控制協定來增加多 重傳輸的數量以及減少干擾的影響。在本篇論文中，我們不嘗試提出一個新的傳 輸功率控制協定，而是研究在每個通道都配置無線電傳輸設備的多通道無線網路 環境中，在多重跳躍通訊環境下，如何應用傳輸功率控制協定。單一無線電傳輸 設備的傳輸端降低傳輸功率，將會導致較低的網路連結率以及較長的傳輸路徑長 度及傳輸媒介利用率，這兩個參數對增加無線網路容量顯的更為重要。由於此動 機，我們提出了一個可以應用在無線電傳輸介面並且獲得多重連結密度的傳輸功 率控制協定，使的一個多重的網路拓樸在多個無限干擾的通道中擁有漸層式連結 度，稱之為漸層式傳輸功率控制協定 (GradPC)。 在我們提出的漸層式傳輸功率控制協定 (GradPC) 中，基本通道被指定預設 的傳輸功率 (無功率控制協定)，而在其他非基本通道中，我們採用鄰近節點傳 輸功率控制的方法來實現漸層連結密度，在漸層式傳輸功率控制協定配置於所有 無線電傳輸介面後，配合 G-mcDSR 路由協定，選擇適當的傳送路徑和分配合適 之傳輸通道。由於漸層式傳輸功率控制協定 (GradPC) 同時考慮路徑長度和傳輸媒介利用率因素。由模擬結果顯示出，漸層式傳輸功率控制協定 (GradPC) 的確優於其他功率控制協定。

Various power control techniques have been proposed to boost aggregate network throughput by reducing the interference impact and encouraging more concurrent transmissions in medium-shared wireless systems. In this paper, we do not intend to devise new power control mechanisms. Rather, we investigate the interoperability of two performance-related parameters, transmit power and radio channel, in a wireless ad hoc network. In our proposed GradPC protocol, a base channel is designated to use default transmit power (no power control on this radio). For other non-base radios, we adopt neighbor-based power control techniques to tailor the connectivity degree for each radio channel. Imagine several superposed network topologies having gradational connectivity levels over multiple non-interfering channels, hence the name, gradational power control (abbreviated as GradPC), is given. A corresponding multi-channel routing protocol, entitled G-mcDSR, is devised to judiciously mix short and long hops over appropriate channels in a multi-hop path. Simulation results demonstrate that the proposed GradPC mechanisms along with G-mcDSR routing protocol outperform other strategies by imposing gradational power levels on radios to balance the requirements for short route and high medium utilization.