隨著時代的需求及技術的演進，多媒體傳輸技術已漸漸成為現今及未來的研究主流，傳輸技術將整合語音(Voice)、影像(Video)及數據資料(Data)等，而非單一重視語音方面而已。目前使用最廣泛的GSM（Global System for Mobile Communication）無線網路系統,只能提供語音服務及少量的數據傳輸服務,已經不能滿足使用者的需求,於是以GSM網路架構為主的GPRS(General Packet Radio Service)網路系統,由此應運而生。由於GSM與GPRS兩個系統是使用共用頻道資源,對數據傳輸方式GSM是採用固定分配方式,而GPRS則採用動態分配方式,所以GPRS網路系統可提供比GSM網路系統更快的數據傳輸速度,及更有效率使用頻道的資源。因數據服務進入系統資料量增加,勢必會影響到語音服務品質QoS(Quality of Service)，所以如何在語音服務與數據服務取得平衡點及有效管理頻道資源將是一個重要課題。本論文針對GPRS動態頻道資源分配的特性，提出過去文獻研究更為周密的頻道資源分配機制,這些機制所採用的技術包括佇列優先序、服務優先序、門檻值控制、頻道保留、頻道釋放、頻道搶奪等策略的組合。論文中所設計的機制利用馬可夫鏈方法進行理論分析,機制效能評估基準包含新進呼叫阻斷機率、交遞呼叫中斷機率、封包遺失機率、接受延遲時間等，並以模擬方式來驗證理論分析結果的準確度。此外，我們也觀察不同的機制在不同參數(如佇列大小、門檻值、數據資料服務時間及資料大小、交遞快慢),對效能的影響。
最後,適合GPRS系統的機制，可透過論文的分析及比較後而得知。

As time goes and technologies evolve, multimedia transmission has gradually become one of the main topics in the contemporary and future research areas. Therefore, transmission technology has the trend to integrate voice, video, and data simultaneously in one system, but not offers voice service only. At present, GSM (Global System for Mobile Communication) wireless network systems that
provide voice services and a small amount data services are most widely used in many nations/regions. The systems have not satisfied users' requirements. Consequently, GPRS (General Packet Radio Service) network system is evolved from GSM network infrastructure as a result of both GSM and GPRS shared channel resource. As for data transmission method, GSM employs fixed channel allocation while GPRS employs dynamic channel allocation. Hence, data transmission rate of GPRS is faster than GSM, and channel allocation is efficient for GPRS. With the traffic of data service increase, quality of service (QoS) of voice service is surely affected. Therefore, how to obtain balance point between voice and data services and how to
efficiently manage channel resource are important issues. In this dissertation, we take a comprehensive approach for channel allocation schemes of GPRS compared with the past studying. The schemes employ the following techniques including buffering priority, service priority, threshold control, de-allocation, preemption strategies etc. We use Markov chain approach to build an analytic model. The performance metrics include blocking/forced-termination/dropping probabilities, and delay times.
Analytical results are validated by simulation. In addition, we observe the impact of performance when changing parameters, e.g., buffer size, the values of threshold, data service time and data size, mobility rate etc. At last, better schemes suitable for the GPRS system are suggested after a thorough comparison on system performance.

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