Abstract

This paper presents impulse response measurements of few-mode optical fibers and transmission lines that were obtained by using coherence-recovered linear optical sampling or a two-comb interferometer. When performing a measurement, the probe pulse source and the sampling pulse source may be far from each other, particularly when the fibers are installed in the field, and the fiber length may exceed several tens kilometers. In this paper, by modifying a previously proposed referencing technique, the coherence between two pulse lasers is equivalently maintained by canceling out the phase noise caused both by the light sources and perturbations in the fiber. Hence, the amplitude averaging is used to enhance the signal-to-noise ratio. As a result, we can measure the impulse responses of multimode fibers with a dynamic range of 80 dB and a time resolution of a few picoseconds, over tens nanoseconds of differential mode delay.

Simultaneous mode-by-mode impulse response measurement of multi-mode optical systems based on linear optical sampling

Takuya Arakawa, Fumihiko Ito, Daisuke Iida, and Tetsuya Manabe
Opt. Express 27(9) 12080-12089 (2019)

Comparison of calculated and measured impulse responses of optical fibers

Katsunari Okamoto
Appl. Opt. 18(13) 2199-2206 (1979)

Clock recovering characteristics of adaptive finite-impulse-response filters in digital coherent optical receivers

Kazuro Kikuchi
Opt. Express 19(6) 5611-5619 (2011)

Coherent linear optical sampling at 15 bits of resolution

I. Coddington, W. C. Swann, and N. R. Newbury
Opt. Lett. 34(14) 2153-2155 (2009)

Impulse response of single-mode fibers with polarization-mode coupling

Claus J. Nielsen
J. Opt. Soc. Am. 73(11) 1603-1611 (1983)