Notes
Occasional longer explanations of topics in microwave photonics and analog circuit design, written for engineers who are new to them. Short tips sit alongside the longer notes.
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Automatic tuning of silicon photonic ring filters
How a small control loop finds each ring's resonance and holds it there despite fabrication variation and temperature drift.
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How a Mach–Zehnder modulator driver sets the limits of a radio-over-fiber link
Why Vπ, bias point, and the driver's output swing decide most of an analog photonic link's gain and dynamic range.
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TipQuick dB arithmetic you can do in your head
Five ratios that cover most link-budget sanity checks.
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Noise figure, explained with one receiver chain
What the Friis formula really says, and why the first stage of a receiver gets most of the design effort.
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TipSanity-check any receiver with −174 dBm/Hz
The thermal noise floor gives you a sensitivity estimate in ten seconds.
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Microring resonators for circuit designers
Resonance, Q, and free spectral range, described with the LC-tank intuition analog engineers already have.