DSL Moving towards Gigabit

Dr. Long Guozhu, Principal Scientist of Huawei, introduces details of Huawei Giga DSL prototype and the perspectives on copper technology development.


DSL technology has been in use for over a decade and every year it seems to reach greater lengths and require more bandwidth thanks to bandwidth-heavy applications such as HDTV. Huawei meets this challenge with Giga DSL (a new-generation single-twist DSL access technology), for which the prototype arrived in December 2011. Delivering 1Gbps uplink & downlink speeds within 100 meters, this technology has the viability to keep copper resources fully utilized over the next decade.

Dr. Long Guozhu, Principal Scientist of Huawei Advanced Access, introduces Huawei’s Giga DSL prototype, while offering his perspectives on copper development and application.

Dr. Long thinks that, compared to fiber and other access media, copper’s main advantage is its low cost, a key factor in network deployment. Vectoring, for instance, requires crosstalk cancellation, leading to complex deployments and increased costs, while G.fast requires expanded bandwidth, which brings higher complexity and lower efficiency. Huawei’s Giga DSL prototype uses a technology called TDD (the ITU’s agreed-upon G.fast element), as opposed to the FDD technology used by VDSL2 and ADSL, which helps reduce the complexity of network rollout.

Legacy copper utilization through new DSL technologies is now a very efficient route to high-speed broadband. Tests with several major operators show that when using 0.5mm copper, Huawei’s Giga DSL prototype delivers uplink/downlink speeds of 550Mbps within 200 meters and up to 1Gbps within 100 meters. In the future, other technologies may co-exist with Giga DSL, and their inter-line crosstalk, counteraction, and other relevant issues will demand continuous industry attention on the research front.