光通信系统中的Super FEC研究
摘要
前向纠错(FEC)技术目前已经被广泛地应用于光通信系统中,以便通过在信号中加入少量的冗余信息来发现并纠正误码,降低接收端的光信噪比(OSNR)容限,从而达到改善系统的误码率性能,提高系统通信的可靠性,延长光信号的传输距离,降低光发射机发射功率以及降低系统成本的目的。
近年来,ITU-T针对光通信系统的迅速发展而开展了FEC码的研究,相继提出了若干与此相关的建议(如ITU-T G.707、G.975、G.709和G.975.1等)。但随着光通信系统向更长距离、更大容量和更高速度的日益发展,光纤中的传输效应就会严重影响传输速率和传输距离的进一步提高。为此,人们不断研究开发性能更好的超强前向纠错(SFEC)方案,使其获得更高的净编码增益(NCG)和更好的纠错性能,满足光通信系统高速发展的需要和尽量避免实施设备昂贵复杂的色散补偿技术等。鉴于光通信系统的这种发展趋势,就有必要深入研究新的SFEC方案,并对其在光通信系统中的应用进行理论分析和实际验证,以期将它更好地应用到光通信系统中来提高光通信系统的通信质量,同时降低系统成本。
本文首先对级联码和交织器进行了研究,主要内容包括级联码系统的编译码结构、常用交织器的分析设计和级联码系统中交织器的设计考虑。然后对ITU-T G.975.1建议中的SFEC方案进行了分析研究,并进行了基于C++平台的计算机仿真。最后,提出了基于级联码系统的新的SFEC方案。
At present, Forward Error Correction(FEC) technologies are widely applied in optical communication systems in order that the error can be found and corrected by adding a small quantity of the redundant information to the signal, as a result, the tolerance of the Optical Signal Noise Ratio(OSNR) for the receiving end is reduced to improve the Bit Error Rate(BER) performance of optical communication systems, enhance the reliability of optical communication systems, extend the transmissiondistance of optical signals, decrease the transmitting power of the optical transmitter and reduce the cost of optical communication systems.
The ITU-T has developed the researches of the FEC codes for the rapid development of optical communication systems for recent years, and the relative recommendations such as ITU-T G.707, G.975, G.709, G.975.1 and so forth have been proposed one by one. However, with the increasing development of optical communication systems toward longer distance, larger capacity and higher bit rate, the further improvements of the transmission rate and distance are heavily limited due to the accumulated optical effects in transmission optical fibers. As a result, it has been becoming necessary to develop the novel more powerful Super Forward Error Correction(SFEC) code type in order to gain the higher Net Coding Gain(NCG) and the better error-correction performance to meet the requirements of the rapid development for optical communication systems, compensate for serious transmission quality degradation and avoid using the dispersion-compensating technologies to need the expensive and complex devices and so forth. Seeing that this developing trend of optical communication systems, it is very necessary to deeply research the novel scheme of the SFEC code type, theoretically analyze and practically verify its application in optical communication systems so as to better and better apply it in optical communication systems to improve the communication quality of optical communication systems and decrease the cost of optical communication systems.
Firstly, concatenated code and interleaver have been researched this dissertation, the main contents are the encoding and decoding structure of concatenated code, the design of interleavers in common use and the rules for designing interleavers in the concatenated code system. Secondly, this dissertation has completed detailed analysis and study on the SFEC schemes in ITU-T G.975.1 proposal, besides, the simulations of three SFEC schemes have been achieved. Finally, the new SFEC schemes based on concatenated code have been designed.
近年来,ITU-T针对光通信系统的迅速发展而开展了FEC码的研究,相继提出了若干与此相关的建议(如ITU-T G.707、G.975、G.709和G.975.1等)。但随着光通信系统向更长距离、更大容量和更高速度的日益发展,光纤中的传输效应就会严重影响传输速率和传输距离的进一步提高。为此,人们不断研究开发性能更好的超强前向纠错(SFEC)方案,使其获得更高的净编码增益(NCG)和更好的纠错性能,满足光通信系统高速发展的需要和尽量避免实施设备昂贵复杂的色散补偿技术等。鉴于光通信系统的这种发展趋势,就有必要深入研究新的SFEC方案,并对其在光通信系统中的应用进行理论分析和实际验证,以期将它更好地应用到光通信系统中来提高光通信系统的通信质量,同时降低系统成本。
本文首先对级联码和交织器进行了研究,主要内容包括级联码系统的编译码结构、常用交织器的分析设计和级联码系统中交织器的设计考虑。然后对ITU-T G.975.1建议中的SFEC方案进行了分析研究,并进行了基于C++平台的计算机仿真。最后,提出了基于级联码系统的新的SFEC方案。
At present, Forward Error Correction(FEC) technologies are widely applied in optical communication systems in order that the error can be found and corrected by adding a small quantity of the redundant information to the signal, as a result, the tolerance of the Optical Signal Noise Ratio(OSNR) for the receiving end is reduced to improve the Bit Error Rate(BER) performance of optical communication systems, enhance the reliability of optical communication systems, extend the transmissiondistance of optical signals, decrease the transmitting power of the optical transmitter and reduce the cost of optical communication systems.
The ITU-T has developed the researches of the FEC codes for the rapid development of optical communication systems for recent years, and the relative recommendations such as ITU-T G.707, G.975, G.709, G.975.1 and so forth have been proposed one by one. However, with the increasing development of optical communication systems toward longer distance, larger capacity and higher bit rate, the further improvements of the transmission rate and distance are heavily limited due to the accumulated optical effects in transmission optical fibers. As a result, it has been becoming necessary to develop the novel more powerful Super Forward Error Correction(SFEC) code type in order to gain the higher Net Coding Gain(NCG) and the better error-correction performance to meet the requirements of the rapid development for optical communication systems, compensate for serious transmission quality degradation and avoid using the dispersion-compensating technologies to need the expensive and complex devices and so forth. Seeing that this developing trend of optical communication systems, it is very necessary to deeply research the novel scheme of the SFEC code type, theoretically analyze and practically verify its application in optical communication systems so as to better and better apply it in optical communication systems to improve the communication quality of optical communication systems and decrease the cost of optical communication systems.
Firstly, concatenated code and interleaver have been researched this dissertation, the main contents are the encoding and decoding structure of concatenated code, the design of interleavers in common use and the rules for designing interleavers in the concatenated code system. Secondly, this dissertation has completed detailed analysis and study on the SFEC schemes in ITU-T G.975.1 proposal, besides, the simulations of three SFEC schemes have been achieved. Finally, the new SFEC schemes based on concatenated code have been designed.
引文
1李玉权译, Gerd Keiser著.光纤通信(第三版).北京:电子工业出版社, 2002.
2毛谦.与光纤通信系统设计有关的几个问题(下).邮电设计技术, 2002, 9:1-9.
3 B. Xie, Z. Li, Y. Guan. FEC Performance of PMD-Impaired Optical Communication System with Multiple Wavelength Interleaving. IEEE Pholonics Technology Letters, 2004, 16(3): 936-938.
4 L. Song, M. L. Yu, M. S. Shaffer. A 10 Gb/s and 40 Gb/s forward error correction device for optical communications. In Proc. ISSCC 2002, San Francisco, CA, Feb. 2002, 8(2): 128-129.
5朗讯科技(中国)有限公司光网络部编著.光通信技术.北京:清华大学出版社,北方交通大学出版社, 2003.
6 J.H.Winters and R.Gitlin.Electrical Signal Processing Techniques in Long-haul Fiber-optic Systems. IEEE Transation Communications, May 1990, COM-32: 474-476.
7 Thomas E.Stern, Krishna Bala. Multi-wave-length Optical Networks. America: Addison Wesley Longman, Inc., 1999.
8龚倩,徐荣,叶小华,张民.高速超长距离光通信技术.北京:人民邮电出版社, 2005.
9杨志勇,杨铸.前向纠错码在高速光纤通信系统中的应用.光通信研究, 2001, 105(3): 1-3
10冯建和,纪越峰,管克俭.前向纠错改善高速光传送网性能分析研究.光通信技术, 2001, 25(1): 35-38.
11 J.G.Proakis. Digital Communications, 3rd edition. New York: McGraw-Hill, 1995.
12 ITU-T Recommendation G.975.Forward error correction for submarine systems. 1996.
13 ITU-T Recommendation G.707.Network node interface for the synchronous digital hierarchy (SDH). 1996.
14 ITU-T Recommendation G.709.Network node interface for the optical transport network (OTN). 2001.
15刘爱珊,杨名. Super FEC技术.光通信研究, 2002, 112(4): 13-14.
16王从国,王俊华,万红,李苹.速率DWDM海底光纤通信系统中的前向纠错编码技术.光通信技术, 2004, 51(2): 62-64.
17张强,席申娥,杨名.超强FEC技术在超长距离光通信系统中的应用.光通信研究. 2004, 121(1): 29-30.
18 ITU-T Recommendation G.975.1.Forward error correction for high bit rate DWDM submarine systems. 2003.
19 J.X.Cai, M.Nissov, C.R.Davidson. Long-haul 40Gb/s DWDM transmission with aggregate capacities exceeding 1Tb/s. Lightwave Technol., 2002, 20:2247-2258.
20梁钊.长距离高速光纤通信中的前向纠错编码技术.光通信技术, 2004, 28(11): 52-55.
21 O.A.Sub. FEC evolution in submarine transmission systems. Presented at the SubOptic 2004, Monaco, Mar. 2004.
22 Y.Cai. Forward error correction codes and line-coding schemes in optical fiber communications. Ph.D.dissertation, Univ. of Maryland Baltimore County, Baltimore, May 2001.
23 T.Mizuochi, K.Kubo, M.Akita, et al. Transparent multiplexer featuring super FEC for optical transport networking. Presented at the SubOptic 2001, Kyoto, Japan, May 2001.
24 E.Yeo, B.Nikolic, V.Anantharam. Iterative decoder architectures. IEEE Commun. Mag.
25 S.R.Weller, S.J.Johnson. Iterative decoding of codes from oval designs. Presented at the Defense Applications of Signal Processing, Workshop (DASP), Adelaide, S.A., Australia, Sep.16-20, 2001.
26 I.B.Djordjevic, B.Vasic. MacNeish–Mann theorem based iteratively decodable codes for optical communication systems. IEEE Commun, Lett., 2004, 8(8): 538-540.
27 K.Seki, K.Mikami, A.Katayama, et al. Single-chip FEC codec using a concatenated BCH code for 10 Gb/s long-haul optical transmission systems. Custom Integrated Circuits Conference, 2003, Proceedings of the IEEE 2003, 279-282.
28 P.Robertson. Illuminating the structure of parallel concatenated recursive systematic (TURBO) codes. In Proc.Globecom, San Francisco, CA, Nov. 1994, 1298-1303.
29 Y.Katayama, T.Yamane. Concatenation of Interleaved Binary/Non-binary Block Codes for Improved Forward Error Correction. OFC2003, Mar. 2003, 391-393.
30 G.D.Forney, Jr.. Concatenated Codes. Cambridge, MA:MIT Press, 1966.
31 S.Benedetto, G.Montorsi.Serial concatenation of block and convolutional codes . Electron.Lett., May 1996, 32(10): 887-888.
32 R.H.Deng, D.J.Costello. High rate concatenated coding systems using bandwidth efficient trellis inner codes. IEEE Trans. Commun., May 1989, 37(5): 420-427.
33 Jinhong Yuan, Wen Feng, B.Vucetic. Performance of Parallel and Serial Concatenated Codes on Fading Channels. IEEE Transactions onCommunications, 2002, 50(10): 1600-1608.
34 D.Divsalar, F.Pollara. Hybrid concatenated codes and iterative decoding. In Proc. Int. Symp. on Inform. Theory, Feb.1997, 32(6): 314-315.
35 S.Benedetto, et al.Serial concatenation of interleaved codes: performance analysis, design, and iterative decoding[J].IEEE Trans.Inform.Theory,May 1998,44(3): 909-926
36袁建国,蒋泽,毛幼菊,叶文伟,王巍. DWDM系统中的前向纠错级联码.激光杂志, 2007, 28(2): 67-69.
37杨志勇,杨铸,肖定中.光纤通信中级联码的码型.通信学报, 2004, 25(2): 82-88.
38熊华,曾常安,王峰.分组、随机交织器相关系数仿真分析.华北电力大学学报, 2007, 12(01): 103-105.
39毕成余,赵力.交织在信道编码中的应用.信息技术与信息化, 2005, 16(02): 45-46.
40徐元欣,王匡,仇佩亮.实现卷积交织的几种实用方法.电路与系统学报. 2001: 829.
41焦耀斌,陈自力,刘云庭.利用N阶幻方设计一种具有低相关特性的交织器.军械工程学院学报, 2003, 20(04): 156-158..
42李轶,范跃祖,李道本,李永会.串行级连卷积码内交织器的优化设计.北京航空航天大学学报, 2003, 2(02): 204-207
43白宝明,马啸,王新梅.随机交织器的设计与实现.通信学报, 2000, 18(06): 20-21.
44顾烊,张萌,孙伟,杨东.一种面向RS码的卷积交织与解交织器的设计.电子器件, 2006, 29(02): 109-111.
45马飞,谢建菲.通信系统的交织器技术.兵工自动化, 2006, 106(04): 19-21.
2毛谦.与光纤通信系统设计有关的几个问题(下).邮电设计技术, 2002, 9:1-9.
3 B. Xie, Z. Li, Y. Guan. FEC Performance of PMD-Impaired Optical Communication System with Multiple Wavelength Interleaving. IEEE Pholonics Technology Letters, 2004, 16(3): 936-938.
4 L. Song, M. L. Yu, M. S. Shaffer. A 10 Gb/s and 40 Gb/s forward error correction device for optical communications. In Proc. ISSCC 2002, San Francisco, CA, Feb. 2002, 8(2): 128-129.
5朗讯科技(中国)有限公司光网络部编著.光通信技术.北京:清华大学出版社,北方交通大学出版社, 2003.
6 J.H.Winters and R.Gitlin.Electrical Signal Processing Techniques in Long-haul Fiber-optic Systems. IEEE Transation Communications, May 1990, COM-32: 474-476.
7 Thomas E.Stern, Krishna Bala. Multi-wave-length Optical Networks. America: Addison Wesley Longman, Inc., 1999.
8龚倩,徐荣,叶小华,张民.高速超长距离光通信技术.北京:人民邮电出版社, 2005.
9杨志勇,杨铸.前向纠错码在高速光纤通信系统中的应用.光通信研究, 2001, 105(3): 1-3
10冯建和,纪越峰,管克俭.前向纠错改善高速光传送网性能分析研究.光通信技术, 2001, 25(1): 35-38.
11 J.G.Proakis. Digital Communications, 3rd edition. New York: McGraw-Hill, 1995.
12 ITU-T Recommendation G.975.Forward error correction for submarine systems. 1996.
13 ITU-T Recommendation G.707.Network node interface for the synchronous digital hierarchy (SDH). 1996.
14 ITU-T Recommendation G.709.Network node interface for the optical transport network (OTN). 2001.
15刘爱珊,杨名. Super FEC技术.光通信研究, 2002, 112(4): 13-14.
16王从国,王俊华,万红,李苹.速率DWDM海底光纤通信系统中的前向纠错编码技术.光通信技术, 2004, 51(2): 62-64.
17张强,席申娥,杨名.超强FEC技术在超长距离光通信系统中的应用.光通信研究. 2004, 121(1): 29-30.
18 ITU-T Recommendation G.975.1.Forward error correction for high bit rate DWDM submarine systems. 2003.
19 J.X.Cai, M.Nissov, C.R.Davidson. Long-haul 40Gb/s DWDM transmission with aggregate capacities exceeding 1Tb/s. Lightwave Technol., 2002, 20:2247-2258.
20梁钊.长距离高速光纤通信中的前向纠错编码技术.光通信技术, 2004, 28(11): 52-55.
21 O.A.Sub. FEC evolution in submarine transmission systems. Presented at the SubOptic 2004, Monaco, Mar. 2004.
22 Y.Cai. Forward error correction codes and line-coding schemes in optical fiber communications. Ph.D.dissertation, Univ. of Maryland Baltimore County, Baltimore, May 2001.
23 T.Mizuochi, K.Kubo, M.Akita, et al. Transparent multiplexer featuring super FEC for optical transport networking. Presented at the SubOptic 2001, Kyoto, Japan, May 2001.
24 E.Yeo, B.Nikolic, V.Anantharam. Iterative decoder architectures. IEEE Commun. Mag.
25 S.R.Weller, S.J.Johnson. Iterative decoding of codes from oval designs. Presented at the Defense Applications of Signal Processing, Workshop (DASP), Adelaide, S.A., Australia, Sep.16-20, 2001.
26 I.B.Djordjevic, B.Vasic. MacNeish–Mann theorem based iteratively decodable codes for optical communication systems. IEEE Commun, Lett., 2004, 8(8): 538-540.
27 K.Seki, K.Mikami, A.Katayama, et al. Single-chip FEC codec using a concatenated BCH code for 10 Gb/s long-haul optical transmission systems. Custom Integrated Circuits Conference, 2003, Proceedings of the IEEE 2003, 279-282.
28 P.Robertson. Illuminating the structure of parallel concatenated recursive systematic (TURBO) codes. In Proc.Globecom, San Francisco, CA, Nov. 1994, 1298-1303.
29 Y.Katayama, T.Yamane. Concatenation of Interleaved Binary/Non-binary Block Codes for Improved Forward Error Correction. OFC2003, Mar. 2003, 391-393.
30 G.D.Forney, Jr.. Concatenated Codes. Cambridge, MA:MIT Press, 1966.
31 S.Benedetto, G.Montorsi.Serial concatenation of block and convolutional codes . Electron.Lett., May 1996, 32(10): 887-888.
32 R.H.Deng, D.J.Costello. High rate concatenated coding systems using bandwidth efficient trellis inner codes. IEEE Trans. Commun., May 1989, 37(5): 420-427.
33 Jinhong Yuan, Wen Feng, B.Vucetic. Performance of Parallel and Serial Concatenated Codes on Fading Channels. IEEE Transactions onCommunications, 2002, 50(10): 1600-1608.
34 D.Divsalar, F.Pollara. Hybrid concatenated codes and iterative decoding. In Proc. Int. Symp. on Inform. Theory, Feb.1997, 32(6): 314-315.
35 S.Benedetto, et al.Serial concatenation of interleaved codes: performance analysis, design, and iterative decoding[J].IEEE Trans.Inform.Theory,May 1998,44(3): 909-926
36袁建国,蒋泽,毛幼菊,叶文伟,王巍. DWDM系统中的前向纠错级联码.激光杂志, 2007, 28(2): 67-69.
37杨志勇,杨铸,肖定中.光纤通信中级联码的码型.通信学报, 2004, 25(2): 82-88.
38熊华,曾常安,王峰.分组、随机交织器相关系数仿真分析.华北电力大学学报, 2007, 12(01): 103-105.
39毕成余,赵力.交织在信道编码中的应用.信息技术与信息化, 2005, 16(02): 45-46.
40徐元欣,王匡,仇佩亮.实现卷积交织的几种实用方法.电路与系统学报. 2001: 829.
41焦耀斌,陈自力,刘云庭.利用N阶幻方设计一种具有低相关特性的交织器.军械工程学院学报, 2003, 20(04): 156-158..
42李轶,范跃祖,李道本,李永会.串行级连卷积码内交织器的优化设计.北京航空航天大学学报, 2003, 2(02): 204-207
43白宝明,马啸,王新梅.随机交织器的设计与实现.通信学报, 2000, 18(06): 20-21.
44顾烊,张萌,孙伟,杨东.一种面向RS码的卷积交织与解交织器的设计.电子器件, 2006, 29(02): 109-111.
45马飞,谢建菲.通信系统的交织器技术.兵工自动化, 2006, 106(04): 19-21.
© 2004-2018 中国地质图书馆版权所有 京ICP备05064691号 京公网安备11010802017129号 地址：北京市海淀区学院路29号 邮编：100083 电话：办公室：(+86 10)66554848；文献借阅、咨询服务、科技查新：66554700 |