Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Optical Channel Aggregation by Coherent Spectral Superposition with
  Electro-Optic Modulators   As the bit rates of routed data streams exceed the throughput of single
wavelength-division multiplexing channels, spectral traffic aggregation becomes
essential for optical network scaling. Here we propose a scheme for all-optical
aggregation of several low bitrate channels to fewer channels with higher
spectral efficiency. The method is based on optical vector summation
facilitated by coherent spectral superposition. Thereby it does not need any
optical nonlinearities and is based on linear signal processing with an
electro-optic modulator. Furthermore, optical phase tuning required for vector
addition can be easily achieved by a phase tuning of the radio frequency signal
driving the modulator. We experimentally demonstrate the aggregation of two 10
Gbaud BPSK signals into one 10 Gbaud QPSK and one 10 Gbaud PAM-4 signal, the
aggregation of two 10 Gbaud QPSK signals into 10 Gbaud QAM-16, as well as the
aggregation of sinc-shaped Nyquist signals. The presented concept of in-line
all-optical aggregation demonstrates considerable improvement in network
spectrum utilization and can significantly enhance the operational capacity
with reduced complexity. It provides a new way for realizing the flexible
optical transmission of advanced modulation format signals, and suits for
future dynamically reconfigurable optical networks. Since the method is based
on linear signal processing with electro-optic modulator, integration into any
integrated photonic platform is straightforward.

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The categories of this paper are: quant-ph
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The categories of this paper are: hep-lat
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The categories of this paper are: hep-ph
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The categories of this paper are: hep-th
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The categories of this paper are: mtrl-th
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The categories of this paper are: math-ph
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The categories of this paper are: alg-geom
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The categories of this paper are: bayes-an
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The categories of this paper are: supr-con
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The categories of this paper are: adap-org
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The categories of this paper are: q-fin
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The categories of this paper are: comp-gas
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The categories of this paper are: chao-dyn
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The categories of this paper are: solv-int
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The categories of this paper are: nlin
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The categories of this paper are: patt-sol