自從DVB-H規範被制定出來後,數位電視也進入手持式的應用,DVB-H是以DVB-T為基礎,再另外制定時間切片機制、MPE-FEC錯誤更正機制、OFDM 4k mode,並且相容於現存的DVB-T機制。 時間切片機制主要是針對手持式系統電量消耗問題而提出的解決方案。而MPE-FEC錯誤更正機制則是針對行動裝置在接收訊號時,因為傳輸過程的雜訊干擾造成傳送資料的損毀而提出的更正策略,採用的是更正能力相當優秀的Reed-Solomon Code理德所羅門碼。DVB-H的影音資料不同於DVB-T直接封裝於MPEG-2傳輸串流中,而是採用IP廣播封包封裝影音串流,再載送於MPEG-2串流之中,也因此能達到相容於DVB-T的目的。 本論文主要實踐播放器系統,從傳輸串流中依序拆解封包,最終將RTP封包內容中的影音資訊取出,進行解碼並影音同步播放。軟體撰寫以C語言實現。
Since the European Telecommunication Standart Institute standardizes the DVB-H standard, the digital TV intrudes into application of handheld device.The fundamental of DVB-H standard is based on DVB-T and additionally incorporates with the techniques of COFDM, Time-slicing,and MPE-FEC for compatible with the existing broadcasting standard. In the application of handheld device, the problem of power consumption is always a design issue. The Tme-Slicing can effectively reduce the most serious power consumption problem of DVB-H demodulator. The MPE-FEC is used to recover the data. This research implements the mechanism of the DVB-H IPDC-Decapsulation. After decoding the A/V data from RTP stream, using Lip Sync to play the A/V data on the Linux environment.