9.6 Microwave Photonics
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Fig. 9.7 Radio-over-fiber concept of a broadband wireless access network for interconnecting
antenna base stations with the central controlling office
9.6 Microwave Photonics
The field of microwave photonics encompasses the study and applications of photonic
devices operating at microwave frequencies. The key components being developed
and applied include the following:
• High-frequency low-loss external optical modulators that have linear transfer
functions and can withstand continuous-wave optical powers up to 60 mW
• Optical sources with high slope efficiencies and low RIN that can be modulated
at tens of GHz
• High-speed photodiodes and optical receivers that can respond to signal frequencies of 20–60 GHz
• Microwave photonic filters that perform the same tasks as standard RF filters.
In addition to device developments, microwave photonics also addresses optical
signal processing at microwave speeds and the design and implementation of
RF photonic transmission systems. For example, applications of photonic signal