Higher Order Modulation Explained, QPSK, 16-QAM, 64-QAM

Whether it’s for long haul telecommunications or for data centers, information is sent by shooting laser light down fiber optic cables using transmitters and receivers. This light is encoded in amplitude and phase using Mach–Zehnder modulators. Winston Way, PhD, Electrical Engineering, and Chief Technology Officer at NeoPhotonics, shares his expertise as he covers QPSK, 16-QAM, 64-QAM, symbol rate, baud rate and polarization. Let us know if you want more of these videos. Winston is interviewed by John Houghton, CEO, MobileCast Media.

[kobrara]

Very thankful cuz this is a concept that people seldom discuss and analyze. After watching dozens of videos, this is the clearest version and it helps a lot, thank you, professor!

[babykyu]

Very thankful cuz this is the concept that people seldom discuss and analyze. After watching dozens of vid, this is the clearest version and it helps a lot, thank you professor!

[DGaller]

First of all great video. I'm happy to see it confirmed for me that DP-QPSK is what 100G generally uses. I see in my job 100G LR transceiver signals channelised into four lanes I assume corresponds to DP-QPSK. Baud rate=symbol rate is another key concept to get. Higher order modulation schemes fit more BITS into each SYMBOL. Maybe it's just me although I find it takes a while to find information on all these concepts and fit the good explanations together.

[estebanpazfaunes]

Great explanation by the professor! thanks you

[te]

Thank you .. do we use these phase modulation on fiber when we use ethernet ? If not then why ?