ZTE has achieved single carrier 400G wavelength-division multiplexing (WDM) signal transmission over 3000km, traversing 10 reconfigurable optical add-drop multiplexers (ROADMs) with an improved frequency spectrum of 4b/s/Hz (bits per second per hertz).
The company said it developed patented Nyquist filtering technology to overcome degradation typically seen as a 400G traverses multiple ROADM components.
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