細胞式行動服務的需求日益增加。一旦對於頻寬的需求大於供給，系統就會發生壅塞，使得使用者的服務品質下降，且收益也會減少。因此，以最有效率的方式使用有限的資源是非常重要的。連結允入控制是一項策略，它可以控制使用者進入網路的數目，進而減少壅塞的發生。然而，只有連結允入控制不能夠提供誘因促得使用者有效率地與理性地使用網路資源。解決此問題的常見方法之一為壅塞定價，其中藉著改變價格去影響使用者的行為。在這篇研究中，我們研究如何在細胞式網路裡結合連結允入控制和壅塞定價去達到最大的效用。我們假設效用是加權阻塞機率的一個函數，而加權阻塞機率是新連結阻塞機率和交遞連結失敗機率的加權總和。我們考慮兩種情境：單細胞以及多細胞。在單細胞情境下，交遞連結抵達速率和新連結抵達速率是獨立的。在多細胞情境下，交遞連結抵達速率和新連結抵達速率以及其他系統參數有關。另一方面，交遞失敗會比新連結失敗更讓人難以接受。因此，系統可保留一些保護通道給交遞連結使用。我們提出一個基於效用的連結允入控制，其中當佔用通道數超過一定門檻時，系統將收取比較高的壅塞價格。我們推導所考慮系統的解析模型。我們開發一疊代演算法去找出穩態機率分佈和我們有興趣的效能量度。有興趣的效能量度包括新連結阻塞機率，交遞連結失敗機率，放棄機率，加權阻塞機率，整體效用，以及收益。我們研究各種系統參數對於不同效能量度的影響，為了比較起見，我們也呈現實施或不實施壅塞價格的傳統方案的效能量度。最後但並非最不重要的，我們使用電腦模擬去驗證解析結果的正確性。

The demand for cellular mobile services is rapidly growing. When the demand for bandwidth exceeds the supply, congestion will occur so that the QoS of users degrades and the revenue is reduced. Hence, it is important to use the limited bandwidth in the most efficient way. Call Admission Control (CAC) is a strategy to control the number of users into the networks to achieve congestion reduction. Nevertheless, only CAC cannot provide incentives to the users to use the network resources rationally and efficiently. One of the common approaches to deal with the problem is congestion pricing, where the behavior of users are affected by changing the charged price. In this work, we study how to maximize the utility by combining call admission control and congestion price in cellular networks. It is assumed that the utility is a function of the weighted blocking probability, which is a weighted sum of the new call blocking probability and the handoff failure probability. We consider two scenarios: single-cell and multi-cell. In single-cell scenarios, the handoff call arrival rate is assumed to be independent of the new call arrival rate. In multi-cell scenarios, the handoff call arrival rate depends on the new call arrival rate and other system parameters. On the other hand, the handoff call droppings are assumed to be less acceptable than new call blockings. Therefore, some guard channels may be reserved for handoff calls exclusively. We propose a utility-based CAC which adopts a higher congestion price when the channel occupancy exceeds a threshold. We derive the analytical models for the systems considered. An iterative algorithm is developed to find the steady state probability distribution and the performance measures of interest. The performance measures of interest are the new call blocking probability, the handoff failure probability, the give-up probability, the weighted blocking probability, the aggregate utility, and revenue. We study the effect of various system parameters on different performance measures. For comparison, we also present the performance of the traditional schemes with or without congestion price. Last but not least, the computer simulation is used to verify the accuracy of the analytical results.

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