ZTE Corporation demonstrated 400G ultra-long high-speed transmissions at the annual Optical Fiber Communication Conference (OFC) held in San Francisco, USA, on March 14th, 2014.

ZTE used its patented technology to achieve 20 DWDM (dense wavelength division multiplexing) channels using 400Gbps single-carrier polarization multiplexing and quadrature phase shift keying (QPSK) signals to successfully transmit 3,600km in standard single-mode fiber when the spectrum efficiency was improved to 4b/s/H.