本研究著眼於解決WiMAX系統中，上傳以及下載所需頻寬的分配問題。目前大多數有關頻寬分配機制的研究多半不同時考量上傳和下載的頻寬分配問題，此外，自私使用者的問題也鮮少被提及。這些自私使用者會藉由傳送誇大的頻寬需求企圖去影響頻寬分配的結果，使自己獲得較多的頻寬，而這樣的行為會侵害到其他使用者的權益而降低資源分配的效率以及公平性。這種自私使用者的問題在一般的日常生活中也存在著。經濟學家們針對這個問題已經有很長期的研究，他們根據經濟學的賽局理論提出了一套數學的方法解決了這個問題。這樣的一套經濟學的方法目前已經被少數研究者應用在無線網路的頻寬分配問題進而使頻寬分配能夠更加公平。然後，由於這樣一套方法是一個使用者與管理者不斷溝通協調的機制，因此它需要花費很長的一段時間才能達到一個穩定的解。此外，這樣的機制也無法完全去除自私使用者對整體公平性所帶來的負面影響。為了解決自私使用者所帶來的問題，我們提出了另一套以搜尋為基礎的價格機制。我們試圖運用我們的機制去減少頻寬使用者和頻寬管理者所需的溝通協調的時間並且儘可能消除自私使用者所帶來的影響。在我們的模擬結果中可以發現，我們的方法確實可以大幅減少溝通協調所需的次數，同時也能矯正和補償自私使用者所帶來的負面效應，使非自私的使用者的權益獲得更大的保障，整體的頻寬分配也更加公平，有效率。

This work addresses the problem of joint uplink and downlink bandwidth allocation in a WiMAX network consisting of a base station (BS) and a number of non-collaborative subscriber stations (SSs). Most of the existing bandwidth allocation mechanisms do not take into account joint rate allocation uplink and downlink streams. Besides, the selfish behaviors of SSs were seldom considered. The selfish users can affect the results of bandwidth allocation by misrepresenting their bandwidth demands to the BS, leading to unfair bandwidth allocation. The economists have studied this issue for a long time and proposed game theoretical approaches to solve this problem. The game theoretical approaches have been adopted by a few research works to solve the problems caused by the selfish users for video transport over WLANs. However, this mechanism is a negotiation process and often needs to take quite a few time to converge to a stable solution and may not completely prevent the negatively effects caused by these strategic users. To overcome these problems, we propose a Search Based Pricing Mechanism based on the game theoretical approaches to reduce the communication time and effectively mitigate the negative effect caused by strategic behavior. Our simulation results show that the proposed mechanism can reduce the communication time significantly as well as converges stably to optimal solutions in small number of iterations.

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