無線通訊常傳輸在連續衰退(continuous fading)通道上,而最適合此種通道的通道碼為位元交錯編碼調變(bit-interleaved coded modulation, BICM)。然而,同調BICM需要傳前導符元(pilot symbol)以做通道估測,但當通道變化較快速時,前導符元須傳送較頻繁,所導致的速率損失(rate loss)也較大。如果這時使用非同調編碼(例如相差編碼),在接收端可以使用非同調檢測,這樣就沒有前導符元的速率損失問題。 本計畫目標是針對連續衰退通道,設計比『使用前導符;The common channel model used for wireless communications is the continuous fading channel. Bit-interleaved coded modulation (BICM) is the most powerful channel code for such channel. However, coherernt BICM needs pilot symbols for channel estimation. If ;研究期間:10408~10507