Enhanced Sample Rate, combined with the low-noise system architecture and the tailored brick-wall frequency response in the HDO4000A, HDO6000A, HDO8000A and MDA800A series oscilloscopes dramatically improves the measurement precision when the input frequency signals are very high frequency, such as a high-frequency sine wave or fast edge.

We present a novel low-loss 3-spot mode coupler to selectively address 6 spatial and polarization modes of a few-mode fiber. The coupler is used in a 66 MIMO-transmission experiment over a 154-km hybrid span consisting of 129-km depressed-cladding and 25-km graded-index few-mode fiber.

We experimentally demonstrate 8 dB of mode-equalized distributed Raman gain using a backward pumping scheme. The equivalent noise figure of the amplifier is -1.5 dB, and the amplifier was successfully employed to demonstrate 6-channel mode-multiplexed MIMO transmission over 137-km few-mode fiber.

Low differential group delay (DGD) between the modes of a graded-index few-mode fiber is obtained by combining segments with DGD of opposite sign. Transmission of mode-multiplexed 620-GBd QPSK over a record distance of 1200 km is demonstrated.

We experimentally demonstrate multiple-input-multiple-output transmission of a combined 3-space-, and 2-polarization-, and 5-wavelength-division multiplex in a 3-core microstructured fiber over 4200 km. This is the record transmission distance for spatial-division multiplexing in a fiber.