A new method for determination of time-resolved frequency chirp in modulated light sources of optical communication systems is presented. A thin silicon wafer acting as a low-finesse etalon was used as an optical frequency discriminator. The method provides a polarization-insensitive way to easily characterize the frequency chirp with high time-resolution.
Tammela, S., Ludvigsen, H., Kajava, T., & Kaivola, M. (1997). Time-resolved frequency chirp measurement using a silicon-wafer etalon. IEEE Photonics Technology Letters, 9(4), 475-477. https://doi.org/10.1109/68.559393