Patent ID: 11937029
Assignee: JUNIPER NETWORKS, INC.
Field: Telecommunications (Electrical engineering)
Classification: CPC H  G | IPC G  H

Claim 0:
1. An intra-datacenter optical switch network comprising:
a plurality of probabilistically shaped quadrature amplitude modulation (PS-QAM) transmitters that each generate probabilistically shaped QAM symbols using a probability distribution to generate a PS-QAM signal, the PS-QAM signal having a modulation order of at least 64-QAM;
a multiplexer that combines the PS-QAM signals from the plurality of PS-QAM transmitters to generate a dense wavelength division multiplexed (DWDM) signal for transmission over fiber within the intra-datacenter optical switch network, the DWDM signal comprising at least 80 DWDM channels at different wavelengths that each comprise one of the PS-QAM signals, the at least 80 DWDM channels in the DWDM signal having spacings of 75 GHz or less;
a demultiplexer that separates the DWDM channels of the DWDM signal;
a PS-QAM coherent receiver to receive one of the DWDM channels after the demultiplexer; and
one or more fiber links less than 2 km in length that transmit the DWDM signal from the multiplexer to the demultiplexer without optical amplification,
wherein:
the at least 80 channels and the spacings of the channels result in the DWDM signal spanning a wavelength band greater than a passband of an Erbium-Doped Fiber Amplifier; and
each PS-QAM transmitter shapes the QAM symbols to reduce cross-talk between the channels of the DWDM signal at the spacings of the channels of the DWDM signal.