Chinese mobile network vendor Huawei has introduced its 400G WDM prototype with Faster Than Nyquist (FTN) technology for long-haul transmission beyond 3,000 km at the OFC 2014 Conference.
Huawei in a statement said FTN technology breaks the limit of the Nyquist sampling theorem, which defines a maximum transmission speed for a fixed channel bandwidth.
By utilizing spectrum compression and signal distortion compensation algorithms, FTN technology achieves long-haul transmission of high baud-rate signals on existing networks.
The technology enables two types of 400G WDM solutions based on 100GHz channel spacing — a short-haul solution and the ultra-long-haul solution unveiled at OFC 2014. The ultra-long-haul solution, which applies to backbone transmission, adopts 2SC-PDM-QPSK modulation and supports a record transmission distance of over 3000 km.
The short-haul solution, which applies to metropolitan area network (MAN) transmission, adopts 1SC-PDM-16QAM modulation and allows high-quality 400G transmission over a single carrier wave. Huawei’s single-carrier 400G solution was recently tested on EXATEL’s live network in Poland.
“Huawei has been investing in the high-speed WDM field. The new FTN technology introduced in the prototype exceeds traditional technological limits to deliver ultra-long-haul 400G transmission, breaking new ground for the 400G industry,” said Jack Wang, president of the Huawei transmission network product line.
