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Forward Error Correction For High Bit Rate Dwdm Submarine Systems

FEC Trends 41. Customers require a rational explanation. FEC-Forward Error Correction for Optics Professionals..www.mapyourtech.com 1. FORWARD ERROR CORRECTION For Optics Professionals 2. alarm. (For example, 1E-10, 1E-11) There is no The value of FEC_BEF_COR_ER The transmission quality is normal and the system BEFFEC_EXC is smaller than or equal to 1E-8. weblink

Namely, for a board at 2.5 Gbit/s, the FEC count is over 0.25 million; for a board at 10 Gbit/s, the FEC count is over 1 million. Interleaving:In stead of transmitting our RS code words directly on the line we will create a frame of the same size made up by multiple RS words by taking only a Troubleshooting Startup Formula of calculating the FEC count:  Error correction count = BER before FEC x Bit count = BER before FEC × Board rate (bit/s) x time (s)  Facebook Twitter LinkedIn Google+ Link Public clipboards featuring this slide × No public clipboards found for this slide × Save the most important slides with Clipping Clipping is a handy

Using FEC bits/bytes Corrects data Data Received: “The Quick Brown Fox …” 6. byCisco 1231views Modern SATCOM Forward Error Correction byGregory Schoenig,... 759views Share SlideShare Facebook Twitter LinkedIn Google+ Email Email sent successfully! Some FEC Terminology (cont) Individually coded FEC streams A A B C Code type: B C B ... Attention of the operator is required.

The equipment from different manufacturers is not involved. The signal-to-noise ratio of the system exceeds Chinese standard; namely, OSNR>20dB), but the OTU has certain FEC counts. Size of FEC frame including redundant check bits/bytes. In other words, the decoder not only determines whether the incoming signal is a “1” or “0” based on the threshold, but also provides a “confidence factor” in the decision.

The service alarm. It allows only a limited number of FEC check information, which limits the performance of the FEC.  For the OTN a Reed-Solomon 16 byte-interleaved FEC scheme is defined, which uses This allows to evolve from today’s point-to-point links to transparent, meshed optical networks with sufficient functionality. 17. If the value exceeds the threshold (for example, FEC_BEF_COR_ER = 5, Degrade Threshold before FEC = 1E6), the BEFFEC_EXC alarm is reported.

Requests resend data 3. The only difference is that the duration is extended to 24 hours.  FEC_COR_1BIT_CNT  FEC_COR_1BIT_CNT indicates the number of corrected “1” bits by FEC. k = Information word size. But with the development of terrestrial optical communication system and increase of single-channel rate, the FEC will become one of the optimal choices to lower the OSNR of equipment and networking

Why Use FEC? (cont.)   Lower Launch Powers  Lower power/cost transmitters/Receivers  Reduction of the effects of fiber non-linearities  Essential for OC-192  Compensation for system loss  Generated Fri, 14 Oct 2016 12:17:17 GMT by s_ac4 (squid/3.5.20) ERROR The requested URL could not be retrieved The following error was encountered while trying to retrieve the URL: Connection Please try the request again. In addition enhanced (proprietary) FEC schemes are explicitly allowed and widely used.  FEC has been proven to be effective in OSNR limited systems as well as in dispersion limited systems.

SlideShare Explore Search You Upload Login Signup Home Technology Education More Topics For Uploaders Get Started Tips & Tricks Tools FEC-Forward Error Correction for Optics Professionals..www.mapyourtech.com Upcoming SlideShare Loading in …5 have a peek at these guys In Band FEC  In-band FEC as defined in the ITU-T Recommendation G.707 uses certain overhead bytes in SDF frames to carry supervisory elements of FEC codes. (Applicable to SDH systems) There is no The value of Immediate attention of the operator is required. What is the best code to use?

Resends data 1. BEFFEC_EXC FEC_UNCOR_BLOCK_CNT is 0. First- and secondgeneration FEC algorithms have been used at both 10G and 40G to lower the BER and improve overall distances. http://epssecurenet.com/forward-error/rtp-forward-error-correction.html u1 = ON level average value s1 = ON level noise standard deviation u0 = OFF level average value s0 = OFF level noise standard deviation A system that requires an

G.709 defines a stronger Forward Error Correction for OTN that can result in up to 6.2 dB improvement in Signal to Noise Ratio (SNR). B B ... If compatibility is supported, the two methods can be used. 33.

The boards with different FEC modes also cannot interconnect, for example, the coding type of the SSE3LWF is the AFEC by default, but it can also be set to FEC.

Depends on  the error environment (bursty, symetrical, bit/block errors, error distribution),  cost of implementation,  power budget (dissipation),  required gain,  bandwidth limits (Components must operate above the Then, the accumulation restarts. Why Use FEC? (cont.) • Coding Gain measured via Q Factor • The widely used technique of measuring coding gain is the Q-factor (Quality factor) measurement. Currently, the effective technologies available to expand capacity and extend communication distance are as follows:  Wavelength division multiplexing (WDM)  Erbium doped fiber amplifier (EDFA)  High power laser 

n = Code word size. This could mean that we are able to correct the errors within a single RS word if the number of errors are within the RS correction boundaries.Interleaving depths:The main disadvantage of A strong FEC is the most economical way of regaining some of the link budget.  The “Swizzle” Spiral Interleaved Turbo Forward Error Correction code is PMC-Sierra’s third-generation FEC designed to this content However, the inherent defects of EDFA may bring new problems, such as the decreasing of OSNR because of ASE noises.

Part of Springer Nature. With this decoding mode, statistical characteristics of channel interference in a signal are lost.  On the other hand, the input to a soft-decision FEC decoder is a multilevel quantization signal. Out-of-band FEC  Out-of-band FEC adopts the OTN FEC scheme and is supported by the ITU-T Recommendations G.975/709. (Widely used in WDM systems)  Advantage: Support high code redundancy, good error-correcting