在最近幾年來，非同調檢測是一種非常受到注目的技術，因為它不需要追蹤任何載波的相位，因此傳送端也不需要傳送任何已知的訊號，藉此減少頻寬的浪費。不過由於接收端並沒有任何東西可以用來作為通道估測的基準，故非同調檢測在使用上會定義一段同調區間(coherence length)，假設訊號在這個區間上所經過的通道變化相同，藉由這個區間中所有的接收訊號，來輔助接收端進行解調和解碼。

針對碼的特性和效能我們採用系統化的分析輔以非固有資訊傳送圖形(EXIT chart)。非固有資訊傳送圖形是一種常被用來分析系統特性的技巧。我們透過外部碼(outer code)和內部調變碼(inner modulaiton code)間的迭代分析，從非固有資訊傳送圖形上我們可以清楚的知道兩者間是否匹配，並進而決定外部碼和內部調變碼的搭配關係。而透過這樣的分析，我們可以去做更進一步的研究。藉由去設計外部碼或內部調變碼，使得兩者在非固有資訊傳送圖形上達到最好的匹配，進而達到系統效能的最佳化。

在這篇論文中，我們的系統是串接了外部碼和內部調變碼，並且這個內部調變碼是專門針對非同調檢設系統去設計的。針對內部調變碼這個部份，我們設計了一種新奇的傳送和接收方法去改善使用傳統內部調變碼的系統的效能，我們稱做"碼字交錯放置傳送和接收方法"。最後，透過模擬的結果得知，藉由使用我們所提出的方法，系統效能可以得到大大的改善。

Noncoherent detection is an attractive technique in this year because it does not require carrier phase tracking. This thesis contains a systematic investigation of practical coding strategies for noncoherent communication over fading channel, guided by explicit comparisons with EXIT chart analysis. Our system is designed into a serial concatenation of a standard binary outer channel code with an inner modulation code amenable to noncoherent detection for noncoherent communication system. Based on the inner modulation codes, we porpose a novel transmission and reeceiving scheme called "Codeword-Interleaved Transmission/Receiving Scheme" to futher improve the noncoherent system. From the simulation result, we can see that the performance improves substantially by using our proposed scheme.

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