為因應多媒體服務需求的日益增長，多媒體廣播╱群播服務和正交分頻多工技術已被利用在許多無線通訊系統中，以增進頻寬使用效率。此外，為求增加系統吞吐量，多媒體廣播╱群播服務同時支援多重解析度服務的資料串流。不過，儘管多媒體廣播╱群播服務支援多重解析度服務，但對應於不同解析度服務的資料串流則是被視為不同的服務而獨立地處理，並且在不同的無線電資源上進行傳送，因此，降低了資源使用效率。在接收端的角度，傳送在高解析度服務通道上的資料中，有部份寶貴的資料是可以用來提昇低解析度服務的接收訊號品質。
在這篇博士論文的第一個部份，我們提出了一套新的調變技術，名為多階層結合調變法，主要目的在增進多解析度多媒體廣播╱群播服務系統的總吞吐量及擴展服務範圍。我們所提出的多階層結合調變法可以完整地應用所有在不同解析度通道中所傳送的資料，來增進各解析度的接收服務品質。此外，在白高斯通道和多路徑衰褪通道下，我們推導出多階層結合調變技術的訊號錯誤率的理論值。再者，不同解析度服務之間的最佳功率分配也在這篇博士論文中探討，基於我們所提出的位元錯誤率近似函數，我們找到了最佳功率分配的解。在觀察分析和模擬的結果，多階層結合調變技術可以很有效地增進系統吐吞量和增進服務範圍，而吐吞量的增加量可超過傳統方法的118%。
在近幾年中，許多的適應資源分配法已被提出來最佳化群播正交分頻多工系統的吞吐量，但是，這些方法皆忽略了多解析度服務的概念，在此篇博士論文中，我們公式化了多解析度群播正交分頻多工系統的資源分配問題。此外，利用高解析度通道傳送低解析度資料的方式，及透過頻率分集結合，必須合併於多解析度群播正交分頻多工系統的資源分配問題中。在此篇博士論文中，我們提出了三階段演算法來解決此一資源分配的問題。由模擬的結果可知，我們所提出的資源分配法可以有效地增進系統吞吐量，而其中頻率分集結合的技術，是有效增進多解析度群播正交分頻多工系統效能的因素之一。

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