1. T IME - AND W AVELENGTH -D IVISION M ULTIPLEXED P ASSIVE O PTICAL N ETWORK (TWDM-PON) FOR N EXT -G ENERATION PON S TAGE 2 (NG-PON2) Speaker ： Pu-Yu Yu Advisor ： Dr. Ho-Ting Wu ​ Date: 2016/1/21

2. OUTLINE PREVIEW PON INTRODUCTION TWDM-PON ARCHITECTURE WAVELENGTH PLAN AND LOSS BUDGET KEY TECHNOLOGIES 40 GB/S TWDM-PON PROTOTYPE CONCLUSION 1

3. PREVIEW P ASSIVE O PTICAL N ETWORK Passive means : no electricity to power or maintain the transmission facility while doing signal processing. In addition to the terminal device need to use electricity, the node between the places only need fiber elements( splitter). Downlink transmission uses broadcast based on time division multiplexing. Passive optical splitter will distribute input optical signal equally by their optical power and transport to optical network users (1 to 16,1 to 32,1 to 64) Uplink transmission uses TDMA 2

4. PREVIEW P ASSIVE O PTICAL N ETWORK 3 OLT: Optical Line Terminal ONT: Optical Network Terminal

5. K IND OF P ON ATM-based PON (APON) – The first Passive optical network standard, primarily for business applications Broadband PON(BPON) – the original PON standard (1995). It enhanced uplink to 622Mbps. Ethernet PON (EPON) – standard from IEEE Ethernet for the First Mile (EFM) group. It focuses on standardizing a 1.25 Gb/s symmetrical system for Ethernet transport only Gigabit PON (GPON) – Developing from BPON,offer high bit rate (2.5 Gb/s) and more flexible services while enabling transport of multiple services. 4

6. INTRODUCTION The next-generation passive optical network stage 2 (NGPON2)project was initiated by the full-service access network(FSAN) community in 2011. Major requirements : at least 40 Gb/s aggregate rate in downstream or upstream, 40 km reach, 1:64 split ratio, 1 Gb/s access rate per optical network unit (ONU). The time- and wavelength-division multiplexed PON (TWDM-PON) proposal which stacks multiple XG-PONs using WDM 5

7. TWDM-PON ARCHITECTURE Four XG-PONs are stacked by using four pairs of wavelengths ONUs are equipped with tunable transmitters and receivers. Optical amplifiers (OAs) are used at the optical line terminal (OLT) side in order to achieve power budget higher than that of XG-PON The optical distribution network (ODN) remains passive since OA and WDM Mux/DeMux are placed at the OLT side. 6

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9. TWDM-PON ARCHITECTURE This baseline architecture can include more pairs of wavelengths and different rates for stacking. Is valuable in the market where multiple operators share one physical network infrastructure. (LLU) Local loop unbundling (LLU) has multiple OLT arrangement. For LLU, each operator would have their own OLT and would contain some set of wavelength channels. 8

10. L OCAL LOOP UNBUNDLING 9

11. WAVELENGTH PLAN AND LOSS BUDGET The first option is to reuse the XG-PON wavelength bands. It is compatible with G-PON and the 1555 nm radio frequency (RF) video overlay channel, but blocks standardized XG-PON. 10

12. Second option is to redefine the C -band to contain both the upstream and downstream wavelengths. Has attractive optical characteristics of using erbium-doped fiber amplifiers (EDFAs) 摻鉺光纖 放大器 for signal amplification, has a higher power budget and a longer reach. 11

13. Another option is a mixture of the above two plans. Downstream channels are designed in the L - minus band, upstream channels located in the C - minus band. 12

14. KEY TECHNOLOGIES The only significantly new components in TWDM-PON are the tunable receivers and tunable transmitters at the ONU. Receiver should tune its wavelength to any of the TWDM-PON downstream wavelengths by following the OLT commands. Candidate technologies : thermally tuned Fabry Perot (FP) filter,angle-tuned FP filter, injection- tuned silicon ring resonator, liquid crystal tunable filter and thermally tunable FP detector. 13

15. KEY TECHNOLOGIES Transmitter can tune its wavelength to any of the upstream wavelengths. The implementation technologies are distributed feedback (DFB) laser with temperature control (TC), distributed Bragg reflector laser without cooling, external cavity laser (ECL) with mechanical control without cooling 14

16. TWDM-PON APPLICATION ADVANTAGE First, the TWDM-PON tunable transceivers reuse the mature tunable optical transport network components. If one technology does not perform to expectation, there are always other options to provide the required functions. Second, TWDM-PON provides significant relief on the specifications of tunable optical transport network components, such as wavelength tuning range, tuning speed, channel spacing, can be dramatically relieved. 15

17. 40 GB/S TWDM-PON PROTOTYPE This prototype employs the C-band wavelength plan(The RF video channel is blocked) The output power for each downstream wavelength is about 10 dBm after the EDFA booster. Transmitter is based on thermally tuned DFB laser with more than 400 GHz wavelength tuning range. Receiver is based on thin film tunable filter in front of a 10 Gb/s APD ROSA. Its wavelength tuning range is more than 800 GHz. 16

18. 40 GB/S TWDM-PON PROTOTYPE The medium access control (MAC) layer functionalities are based on XG-PON transmission convergence layer Modules such as dynamic bandwidth allocation, forward error correction (FEC), scrambling, XG- PON encapsulation mode (XGEM) are integrated to demonstrate a full-system operation. The ODN contains two stages of splitters. A 1:8 splitter is followed by a 1:64 splitter to provide a total split ratio of 1:512. 17

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21. THREE TEST FOR PROTOTYPE The first test set is for the downstream performance evaluation. Receiver sensitivity for one of the four downstream wavelengths when each signal is modulated using 2^31 – 1 PRBS at the rate of 10 Gb/s. When the bit error rate (BER) is 10^-3, the measured receiver sensitivity is about -30 dBm. 20

22. R X SENSITIVITY OF 1557.36 NM DOWNSTREAM SIGNAL. 21

23. THREE TEST FOR PROTOTYPE The second test is evaluates the upstream performance. In the upstream power budget tests, the input signal is modulated using 2^31 – 1 PRBS at the rate of 2.5 Gb/s. 22

24. U PSTREAM POWER BUDGET WITH 20 KM FIBER. 23

25. THREE TEST FOR PROTOTYPE The third set of tests is to evaluate the coexistence performance with legacy PONs in the same ODN. Three streaming IP video users are connected to the G-PON ONU, XG-PON ONU, and one of the four TWDMPON ONUs. There was no packet loss observed during the test for all the downstream and upstream wavelengths in the three PONs. Also changed the ODN configuration into 1:128 split with 40 km and 1:64 split with 60 km to evaluate the prototype system performance. 24

26. CONCLUSION TWDM-PON leverages the research and development effort in PON industry by stacking four XG-PONs to reach an aggregate access rate of 40 Gb/s. 40 dB power budget in the downstream and 38 dB power budget in the upstream have been achieved. Total split ratio of 1:512 and a distance of 20 km. Successful coexistence of G-PON, XG-PON, and TWDM-PON without service degradation. 25

27. REFERENCE http://www.cs.nccu.edu.tw/~lien/NIIslide/PON/ha rdcopy.htm http://www.plankoe.com/products/Gpon.htm Yuanqiu Luo, Xiaoping Zhou, Frank Effenberger, Xuejin Yan, Guikai Peng, Yinbo Qian, and Yiran Ma, JOURNAL OF LIGHTWAVE TECHNOLOGY, VOL. 31, NO. 4, FEBRUARY 15, 2013 26