由於DVB-H技術規格於2004年11月正式成為歐洲電信標準學會(European Telecommunications Standards Institute；ETSI)之標準，使得行動裝置收看數位電視已成為一種可行的服務。手持式數位視訊廣播(Digital Video Broadcasting - Handheld；DVB-H)是以地面數位視訊廣播(Digital Video Broadcasting - Terrestrial；DVB-T)為基礎，為了降低行動裝置的功率消耗及通道雜訊的容忍力，在資料鏈結層新增時間切片(Time-Slicing)及多重協定封裝-向前錯誤更正機制(Multi-Protocol Encapsulation - Forward Error Correction；MPE-FEC)兩項關鍵技術，並且可以向後相容於現有的DVB-T系統。
本論文針對DVB-H在鏈結層新增的兩項關鍵技術，提出一個可同時最佳化這兩項技術的演算法。其中演算法主要是實行在DVB-H的鏈結層及應用層，首先我們利用Greedy Approach在一有限的頻寬下將每一部影片做時間排程，同時經由每一組的時間排程及通道傳輸速率得到每一部影片在鏈結層所能傳送的資料量，接著再估計每一部影片在鏈結層所能傳送的影像(frame)張數，此時需考慮接收端位於應用層的video buffer，應避免傳送的資料量造成buffer overflow及underflow，接著在鏈結層考慮當影像的封包遺失所造成的影像失真度來決定每個封包的重要程度，並利用動態規劃(Dynamic Programming)的方法依據這些重要程度來決定每個MPE-FEC要加多少保護，透過此排程結果來傳送影片，讓使用者可以接收到最好的影像品質。

Since November 2004 the DVB-H specification has become a key criterion of the European Telecommunications Standards Institute (ETSI) which makes the mobile devices to watch a digital television (DTV) becoming a feasibility service. Digital video broadcasting – Handheld (DVB-H) is based on the digital video broadcasting – terrestrial (DVB-T) in order to reduce the power consumption of mobile devices and channel noise toleration. Moreover, the time-slicing of data link layer and multi-protocol encapsulation - forward error correction (MPE-FEC) are two key techniques which can be compatible with the existing DVB-T system.

In this thesis, we add two key techniques in the link layer for DVB-H system and propose an algorithmic method that can simultaneously optimize these two key techniques. Among them, the usefulness of algorithmic method can be implemented in both the link layer and the applied layer of the DVB-H system. First, we utilize the Greedy Approach to sort the video time at a limited resource, and according to the time arrangement and channel transmission rate, we can obtain the data of the link layer in each video. For a estimation of the transmission frame numbers of the link layer in each video, we need to carefully consider the receive terminal in the applied layer based video buffer to avoid the results of buffer overflow and underflow of the data transmission. Next, the link layer considers the loss of the video package resulting in the video distortion to decide the importance of the each package. And we also utilize the dynamic programming method based on the important level to decide how well the MPE-FEC should be protected; hence, we can get through the sort results to transmit videos that help the users to receive the best quality video format.

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