  In this paper we consider the influence of collisional fluctuations on the
Mollow spectra of resonance fluorescence (RF). The fluctuations are taken into
account by a simple shift of the constant detuning, involved in a set of
optical Bloch equations by collision frequency noise which is modelled by a
two-step random telegraph signal (RTS). We consider in detail the Mollow
spectra for RF in the case of an arbitrary detuning of the laser frequency,
where the emitter is a member of a statistical ensemble in thermodynamic
equilibrium with the buffer gas at temperature $T$ which is treated as a
colored environment, and velocity $v$ is distributed with the Maxwell-Boltzmann
density.
