越來越多使用者要求在移動時可進接大型多媒體檔案，例如，高解析度音頻，視訊與圖像。因此無線數據網路的行動性頻寬需求以指數成長。為了滿足使用者的需求，現在的多頻帶無線路由器被設計成為可同步支援多於一個頻帶。目前的多頻帶無線路由器使用二個不同頻帶，但卻沒有充分利用低使用率的頻帶。無線頻譜是稀有的資源。另一方面，不同封包可能有不同的服務品質需求。因此，為了確保系統資源使用率最大化和對於不同類別之封包提供服務差異化，我們必須針對多頻帶行動路由器提出一個適合的排程和佇列管理機制。我們研究具有三個頻帶或佇列的多頻帶路由器效能。我們考慮三種不同類別的封包：控制更新、即時和非即時。首先，我們考慮傳統的多頻帶行動路由器，其中在不同佇列之間不支援溢流。再來，我們考慮第一類分享式多頻帶行動路由器，其中在不同佇列之間支援溢流，且在相同佇列之中不同類別的封包有著相同的平均服務時間。最後，我們考慮第二類分享式多頻帶行動路由器，其中在不同佇列之間支援溢流，且在相同佇列之中不同類別的封包有著不同的平均服務時間。對於第一類和第二類的分享式多頻帶行動路由器，在每一個佇列之中不同類別的封包被給與對應的非占先優先權。針對每個我們考慮的多頻帶行動路由器，我們開發對應的解析模型。對於第一類分享式多頻帶行動路由器，我們比較提出模型和近似模型的結果。我們研究不同系統參數，例如新封包抵達速率，對於效能指標的影響。我們感興趣的效能指標包含每一類別封包的封包遺失機率、成功送達率、通道利用率和平均系統延遲。我們也呈現傳統、第一類和第二類的多頻帶行動路由器之間的效能差異。最後但不是最不重要的，我們使用visual C++來撰寫電腦模擬程式以驗證解析結果的準確性。

More and more users demand mobility in accessing large multimedia files, such as high definition audio, video, and images. Thus, bandwidth demand with mobility in wireless data networks is increasing exponentially. In order to satisfy users’ needs, today multi-band wireless routers are designed to simultaneously support more than one frequency band. Current multi-band Wi-Fi routers utilize two different bands without exploiting the under-utilized spectrum. The wireless spectrum is a scarce resource. On the other hand, different packets may have a different quality of service requirement. Therefore, it is necessary to come up with an appropriate scheduling and queue management scheme for the multi-band mobile routers to ensure the maximum possible utilization of the system resources and provide service differentiation among different classes of packets. We investigate the performance of multi-band mobile routers (MBMR) with three frequency bands or queues. There are three classes of packets: binding-update, real-time, and non-real-time. First, we consider the traditional MBMR (TMBMR), where no overflow is allowed among different queues. Second, we consider the class-1 shared MBMR (SMBMR-I), where overflow is allowed among different queues and the average service times of different packets at the same queue is identical. Third, we consider the class-2 shared MBMR (SMBMR-II), where overflow is allowed among different queues and the average service times of different packets at the same queue may be different. For SMBMR-I and SMBMR-II, the non-preemptive priority is assigned to different classes of packets at each queue. We develop the analytical model for each MBMR considered. We compare the results of the proposed model and the approximation scheme for SMBMR-I. We study the effect of various system parameters, e.g., the new packet arrival rate, on the performance measures of interest. The performance measures of interest include the packet loss probability, throughput, utilization, and average system delay of each class of packets. We also present the performance difference of TMBMR, SMBMR-I, and SMBMR-II. Last but not least, simulation programs are written in visual C++ to verify the accuracy of the analytical results.

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