Title: 高速光纖系統應用波長編碼之研究
WDM Coding for High-Speed Lightwave Systems
Authors: 邵守國
Shou-Kuo Shao
高銘盛
Ming-Seng Kao
電信工程研究所
Keywords: 高速光纖系統;分波多工;編碼;High-speed Lightwave Systems; WDM; Coding
Issue Date: 1992
Abstract: 錯誤更正碼在高速光纖通訊系統中尚未被廣泛使用, 其原因如下: 1) 編
碼通常會改變系統的傳輸速率, 2) 編碼所需的訊號處理過程在高速光纖
通訊系統上很難完成。3) 編碼所得的效益在光通訊系統``功率-限制''模
式下很低。在本篇論文中, 我們提出一種應用光通訊波長領域,並列式,頻
道間的錯誤更正碼系統 -- 波長編碼系統。此種方法不同於傳統串列式編
碼系統而可提供許多優點。首先,資料完全未被編碼過程改變,使得波長
編碼系統極適用於實際的光纖通訊系統。其次,波長編碼系統的編碼方式
較串列式編碼系統簡單。與串列式編碼系統比較之,波長編碼系統 可以大
量地減少編碼器及解碼器的數量。再者,波長編碼系統在光 纖通訊系統
``波散-限制'' 操作模式下可以提供無限大的編碼增益。最後, 波長編碼
系統可以更正發生在一個頻道上的成串錯誤。 然而, 波長編碼系統受限
於資料編碼數目而無法於少量資料頻道的環境中有效使用。我們於第三章
提出另一種改良式的波長編碼系統。改良式波長編碼系統保有絕大部份波
長編碼系統的優點,並可將同位元檢查頻道的數目由原波長編碼系統的 r
個降低到一個,因而大大地提高了同位元檢查頻道的效率。另外, 改良式
波長編碼系統亦提供更彈性化的編碼方式而能滿足使用者的需求。
FEC are rarely used in practical lightwave systems because: 1)
coding in general changes system bit rate, 2) the required
signal processing in encoding/decoding processes is difficult
in high-speed lightwave systems, and 3) coding gain is small in
power-limited lightwave systems. Nevertheless, some practical
applications of forward error correction (FEC) code at the rate
of DS-3 and STS-1 are presented by Grover and Moore. They
intelligently put the parity-check bits in the unused stuffed
bits and unassigned overhead fields in DS-3 and STS-1 in order
not to alter the system bit rate. However their approaches
demand accurate timing control and complicated coding
processes, therefore they can only be implemented at the STS-1
level. We propose an interchannel parallel coding scheme in the
wavelength domain--the WDM coding system. The system differs
from usual serial coding systems and provides many advantages.
First, data channels are completely unaltered in the coding
Secondly, parallel encoding/decoding are simpler than those of
coding systems.Thirdly, comparing to serial coding, WDM coding
is able to reduce heavily the number of encoding/decoding
pairs. Finally, WDM coding systems could correct single channel
burst We have evaluated the system performance and analyzed the
system limitation imposed by bit-skew among wavelength
channels. To reach an efficient and flexible WDM coding system,
we further propose a modified WDM coding system with single
parity-check channel in Chapter 3. The system provides most of
the advantages of original WDM coding systems and can much
increase the of the parity-check channel. We have evaluated the
system and analyzed the performance of frame synchronization
needed for modified WDM coding system.
URI: http://140.113.39.130/cdrfb3/record/nctu/#NT810436015
http://hdl.handle.net/11536/56996
Appears in Collections:Thesis