Abstract
The reflectionless transmission of electromagnetic waves in one-dimensional multi-layer plasmas is studied. The wave transmittance is obtained analytically for single-layer underdense plasma as well as for two-layer critical plasma where the wave frequency ω is equal to the electron plasma frequency ωpe, and it is shown that reflectionless transmission can be possible for both cases. Reflectionless transmission in two-layer critical plasma as well as in single-layer underdense plasma should be considered Fabry-Perot resonance well-known in optics.