98957 - Laboratory of Microwave Photonics T

Learning outcomes

At the end of the course the student will be aware of how Radio signals, as well as Microwave, Millimeter-Wave and THz-frequency signals, can be efficiently controlled and distributed exploiting their appropriate interaction with the Optical ones. He/she will know how to measure the main parameters of Optical and RF devices and components, becoming familiar with the appropriate instrumentation. The student will finally be able to perform the experimental characterization of various systems, whose applications range from wireless communications and radars, up to sensors and radio astronomy, which will comprise the determination of multi-port scattering parameters, the acquisition of antennas radiation patterns, the evaluation of optical fiber systems for the remotization of antennas / array of antennas, and the performance assessment of optically controlled beamforming antennas.

Course contents

Theoretical Part

The concept of Microwave Photonics will be explained and detailed about the components, architectures and main parameters which must be taken into account during the design phase. In detail:

• Introduction to Microwave Photonic Systems, technologies and applications
• Radio-over-Fiber (RoF): principles, technologies and architectures
• Theoretical basics on the main optical components, such as LED/LASER, Optical Fiber and PhotoDetector
• Description of the main quantities which characterize the design of a RoF link: Gain, Noise Figure, 1dB Compression Point, Intercept points, Spurious Free Dynamic Range.

Experimental Part

Experimental setup will be realized by students to characterize the various component of a Microwave Photonic system. In particular:

• Realization of an experimental setup for the DC characterization (L-I-V curve) of the laser diode and its monitoring current.
• Measurement of the attenuation produced by the optical fiber
• DC Characterization of the Photodiode and its main parameters.
• RF measurement of the reflection coefficients of laser diode and photodetector using a Vector Network Analyzer (VNA)
• Experimental test of Bias-T, Matching Circuit and Low Noise Amplifier (LNA)
• RF Gain Measurement of the optical link as a function of the laser parameter
• Measurement of 1dB compression point, and higher order non linear effect.
• Measurement of the noise introduced by the optical link and evaluation of the dynamic range of the link.

The following instrumentation will be used during the experimental activity:

• DC Voltage Generator
• Laser Driver
• Digital Multimeter
• Optical Power Meter
• Vector Network Analyzer
• Electrical Spectrum Analyzer
  

Readings/Bibliography

• Cox III, Charles H, Analog Optical Links: Theory and Practice, 2004, Cambridge University Press
• Vincent J. Urick Jr, Jason D. Mckinney, Keith J. Williams, Fundamentals of Microwave Photonics, 2015, John Wiley & Sons, Inc
• S. Iezekiel Ed., Microwave Photonics: Devices and Applications, 2009, Wiley

Teaching methods

Theory explanantions (using Slides and/or Blackboard) followed by Lab Exercises

Assessment methods

Oral Exam with the analysis of the Lab reports.

Office hours

See the website of Jacopo Nanni