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Photonically enabled agile rf waveform generation by optical comb shifting.

Christopher M Long1, Daniel E Leaird, Andrew M Weiner

  • 1School of Electrical and Computer Engineering, Purdue University, 465 Northwestern Avenue, West Lafayette, Indiana 47907-2035, USA. long25@purdue.edu

Optics Letters
|December 3, 2010
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Summary
This summary is machine-generated.

We developed a new photonic arbitrary waveform generator that quickly switches between radio frequency (RF) waveforms. This device uses optical frequency shifting to select different programmed patterns, achieving rapid updates for advanced signal generation.

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Area of Science:

  • Photonics
  • Radio Frequency (RF) Engineering
  • Optical Signal Processing

Background:

  • Arbitrary waveform generators (AWGs) are crucial for testing and simulating complex signals.
  • Existing AWGs face limitations in switching speed and flexibility.
  • Photonic approaches offer potential for high-speed signal generation.

Purpose of the Study:

  • To present a novel photonically enabled RF arbitrary waveform generator.
  • To demonstrate rapid switching between two output waveforms.
  • To achieve high update rates for RF signal generation.

Main Methods:

  • Utilizing line-by-line shaping of an optical frequency comb.
  • Employing a single diode laser as the optical source.
  • Converting shaped optical pulses to RF waveforms using a fast photodetector.
  • Selecting different patterns via laser frequency shifting and an optical pulse shaper.

Main Results:

  • Demonstrated rapid switching between two output waveforms.
  • Achieved minimum update delay times as low as 0.45 nanoseconds (ns).
  • Successfully generated RF arbitrary waveforms using photonic techniques.

Conclusions:

  • The proposed photonic approach enables high-speed arbitrary waveform generation.
  • The demonstrated rapid switching capability is beneficial for dynamic signal applications.
  • This technology offers a promising alternative for next-generation RF signal generators.