Redesigned point-to-point
optical transceiver for
an energy-efficient access network
CEET : Alan Lee, Jack Li, Kerry Hinton
Bell Labs : Keith Chow, Prasanth Anthapadmanabhan
17 November 2014
Background
� Optical access is the most energy-efficient wireline access
technology
� Are there any solutions to further reduce the power consumption?
� Our focus is on the point-to-point (PtP) access network
� Investigate and develop
• Low-power hardware - transceiver, packet-switch, system architecture
• Power-saving software – adaptive power control, sleep-mode operation
2
Power consumption of PtP optical TRx 2010
� Optical transceiver (TRx) consumes
- up to 40% of the power consumption (ref: European CoC)
� TRx operates at the max. power consumption
- regardless of the link conditions (e.g. distance)
� Our goal
� Reduce the power consumption of the TRx
�Develop new TRx hardware and software for a PtP connectivity
3
Realization of low-power PtP TRx
� Redesign the electronics (ASIC) for PtP connectivity
� With a data rate of upto 1 Gb/s
� With a higher energy-efficient architecture in CMOS
� Transistors are built in blocks
• Enables “turn-on-as-you-go”
• Provides flexibility for power adaptation
� Develop an adaptive power control algorithm
� Automatically optimize the power consumption
• During the link initialization
4
Applications of the PtP transceiver
5
Internet service
provider (ISP)Subscriber ONU ONU
PtP Business internet subscribers In-premise network
Devices
Business
Residential
Physical Testbed – HD video streaming
6
ONU
20km
Fiber
Power
meter
Receiver
Transmitter
OLT
ASIC on PCB
Measured power consumption
7
CEET TRx Power (mW) A Commercial TRx power (mW)
Transmitter 17.5 310
Receiver 5.5 500
Total <23 mW 810 mW
Energy improvement per transceiver > 30x
� Applying to the global PtP business subscriber links
� Between local exchanges and business subscribers
� In-premise networks
� Overall power consumption is reduced by 46%
� 1.1 TWh ≈ 160,000 cars off-the-road annually *
Global power saving
8 *Ref. : http://www.epa.gov/
Contribution to Green Meter (2010 vs.2020)
� Comparing PtP access technologies between 2010 & 2020
� The use of our new TRx in the consumer in-home networks
� And other expected hardware improvements
�The power consumption will be reduced by 80%
= 40 fold overall energy-efficiency improvement
9
Residential
