Tuesday, December 13, 2011

Huawei Claims TDD DSL Achieves Symmetric 1 Gbps over Twisted Pair at 100m

Huawei announced a prototype Giga DSL system that employs time division duplex (TDD) to achieve a total upstream and downstream rate of 1,000 Mbps over a single twisted pair. The company said that by using low-power spectral density in-signal transmission, its Giga DSL prototype reduces radiation interference and power consumption, and provides a total upstream and downstream rate of one Gbps within 100 meters, and 500 Mbps-plus within 200 meters.

Huawei noted that the ITU-T set up a G.fast project team earlier this year to develop new standards for ultra-speed access at short distances. The project's aim is to achieve 500 Mbps access rate per twisted pair within 100 meters. Huawei has actively participated in the work of the team and has become a major technical contributor, having recently worked to incorporate TDD-OFDM (Orthogonal Frequency Division Multiplexing) as a G.fast modulation mode.

Dr. Long Guozhu, Huawei’s Principal Expert of DSL technology, said, “Huawei has taken the lead in developing a Giga DSL prototype because of our rich capabilities and industry-leading technical strength in access networks. It was inevitable that spectrum expansion would help us improve the rate of a twisted pair at a short distance, but after the spectrum is expanded, a technical issue appears: how to design the high-speed physical layer and high-frequency analog front end (AFE). To tackle this issue, Huawei’s FBB Innovation Lab used the core solution TDD-OFDM, which simplifies the physical-layer architecture and the AFE design, while at the same time makes it possible to be downward compatible with traditional ADSL/VDSL2 technologies.�?

Huawei also recently announced the successful development of the world’s first node level vectoring (NLV) prototype. Huawei’s vectoring product provides 100 Mbps access over a single twisted pair in FTTC/FTTB, and has been tested and commercially trialed with many leading telecom operators. This, along with the company’s latest prototype, Giga DSL, signifies that DSL technology still has great potential to meet the requirements of broadband users for ultra-high-speed access in the future.