This study examines the dynamics of spatial frequency modulation (SFM) of \(q\) -Gaussian laser beams propagating through preformed collisional plasma channels characterized by radial inhomogeneity. The influence of self-focusing on SFM is investigated in detail. We utilize moment theory to examine the nonlinear interaction between the laser beam and the plasma, concentrating on the evolution of the spatial frequency of the laser beam. Our findings demonstrate a intricate relationship among the laser’s initial parameters, the plasma density profile, and nonlinear ohmic heating effects of plasma electrons, culminating in the spatial frequency modulation of the laser beam. This modulation has significant implications for applications such as optical communication and high-harmonic generation.
