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Related Experiment Video

Updated: May 18, 2026

Generation and Coherent Control of Pulsed Quantum Frequency Combs

Generation and Coherent Control of Pulsed Quantum Frequency Combs

Published on: June 8, 2018

Versatile offset-free 16-QAM single dual-drive IQ modulator driven by binary signals.

Antonio Malacarne¹, Francesco Fresi, Jonathan Klamkin

¹CNIT—National Laboratory of Photonic Networks, 56124 Pisa, Italy. antonio.malacarne@ircphonet.it

|October 3, 2012

Summary

A novel IQ modulator generates offset-free 16-quadrature amplitude modulation (QAM) signals using equal-amplitude binary inputs. This design, featuring tunable splitters, also supports more efficient hexagonal 16-QAM constellations.

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Area of Science:

Optical communications
Digital modulation techniques

Background:

Quadrature Amplitude Modulation (QAM) is crucial for high-capacity optical transmission.
Generating offset-free QAM signals efficiently remains a challenge.

Purpose of the Study:

To propose and validate a customized IQ modulator for offset-free 16-QAM generation.
To demonstrate the feasibility of using tunable splitters for advanced QAM constellations.

Main Methods:

Simulations were used to validate the proposed IQ modulator design.
The modulator is driven by equal-amplitude binary signals.
Tunable splitters are incorporated into the transmitter architecture.

Main Results:

The proposed IQ modulator successfully generates offset-free 16-QAM signals.
The design demonstrates the feasibility of the transmitter.
The system enables more efficient constellations, including hexagonal 16-QAM.

Conclusions:

The customized IQ modulator offers a viable solution for generating offset-free 16-QAM.
Tunable splitters enhance transmitter flexibility and enable spectral efficiency improvements.