Transcript TWDM-PON

TIME- AND WAVELENGTH-DIVISION
MULTIPLEXED PASSIVE
OPTICAL NETWORK (TWDM-PON)
FOR NEXT-GENERATION
PON STAGE 2 (NG-PON2)
Speaker：Pu-Yu Yu
Advisor： Dr. Ho-Ting Wu
Date: 2016/1/21
OUTLINE
PREVIEW PON
 INTRODUCTION
 TWDM-PON ARCHITECTURE
 WAVELENGTH PLAN AND LOSS BUDGET
 KEY TECHNOLOGIES
 40 GB/S TWDM-PON PROTOTYPE
 CONCLUSION
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PREVIEW PASSIVE OPTICAL NETWORK
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
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PREVIEW PASSIVE OPTICAL NETWORK
OLT: Optical Line Terminal
ONT: Optical Network Terminal
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KIND OF PON
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.
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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
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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.
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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.
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LOCAL LOOP UNBUNDLING
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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.
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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.
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Another option is a mixture of the above two
plans.
 Downstream channels are designed in the Lminus band , upstream channels located in the Cminus band.
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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, injectiontuned silicon ring resonator , liquid crystal
tunable filter and thermally tunable FP detector.
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KEY TECHNOLOGIES
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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
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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.
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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.
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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, XGPON 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.
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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.
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RX SENSITIVITY OF 1557.36 NM
DOWNSTREAM SIGNAL.
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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.
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UPSTREAM POWER BUDGET WITH 20 KM
FIBER.
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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.
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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.
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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
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