  We present a theoretical study on the effect of radiation on the
mangetoresistance of two-dimensional electron systems with strong Rashba
spint-orbit coupling. We want to study the interplay between two well-known
effects in these electron systems: the radiation-induced resistance
oscillations and the typical beating pattern of systems with intense Rashba
interaction. We analytically derive an exact solution for the electron wave
function corresponding to a total Hamiltonian with Rashba and radiation terms.
We consider a perturbation treatment for elastic scattering due to charged
impurities to finally obtain the magnetoresistance of the system. Without
radiation we recover a beating pattern in the amplitude of the Shubnikov de
Hass oscillations: a set of nodes and antinodes in the magnetoresistance. In
the presence of radiation this beating pattern is strongly modified following
the profile of radiation-induced magnetoresistance oscillations. We study their
dependence on intensity and frequency of radiation, including the teraherzt
regime.
