整合訊源與通道編碼調變之研究

Abstract

在這篇論文中，我們考量整合訊源與通道編碼調變(JSCCM)之設計問題，此整合包含高效率的離散且無記憶性的訊源壓縮與其在無記憶性通道上使用 16-QAM調變的穩定傳輸。針對8個可能性的訊源，我們以程式搜尋建立了不同傳輸穩定性要求的JSCCM，並與同樣條件下所建立的VLECPC串接16QAM的系統進行效能比較。我們使用兩種不同的解調器來進行效能驗證，一為基於硬式判定 ，另一則是基於軟式判定。模擬結果顯示不論是在平均碼長或是系統錯誤率上 ，JSCCM 皆優於VLECPC+16QAM系統。

In this thesis, a joint source-channel coded modulation (JSCCM) problem that combines the efficient compression of discrete memoryless sources with their reliable communication over 16QAM based memoryless channels is considered. We construct algorithmically 8-source JSCCMs and compare them with the system of 8-source variable-length error-correcting prefix codes (VLECPC) in connection with 16QAM mapper. We then examine their performances with two different demodulators: one is hard-decision based and the other is soft-decision based. Simulations show that JSCCMs can provide a certain gains over the system with VLECPC+16QAM mapper of comparable free Euclidean distance in terms of average symbol word length and error performance.