We report the identification of two statistically significant quasiperiodic oscillations in the weekly binned $\gamma$-ray light curve of the flat-spectrum radio quasar PKS 0805-07, observed by Fermi-LAT over the period MJD 59047.5-59740.5. By applying a suite of complementary time-series analysis techniques, we identify periodic signatures at $\sim 255$ and $\sim 112\mathrm{days}$. These techniques include the Lomb-Scargle periodogram, weighted wavelet Z-transform, REDFIT, date-compensated discrete Fourier transform , phase dispersion minimization, and the string-length method. The reliability of these signals is supported by high local significance ($\ge 99\%$) in all methods and reinforced through phase-folding. Model selection using the Akaike information criterion and Bayesian information criterion strongly supports a two-component periodic model. The detection of dual quasiperiodic oscillations is rare among blazars and suggests complex variability mechanisms. Although a binary supermassive black hole scenario could be considered given the source’s high redshift ($z=1.837$), the short periodicities are difficult to reconcile with orbital motion unless invoking extreme parameters. Double-sine model fitting reveals that the oscillatory components have comparable amplitudes but are out of phase, suggesting a potential beating phenomenon due to interference. This amplitude-modulated variability is consistent with a geometric origin, most plausibly jet precession driven by Lense-Thirring torques, superimposed with a secondary process such as polar jet oscillation. Doppler factor modulation arising from these effects can account for the observed flux variations without requiring an unrealistically compact binary.

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• Gamma ray astronomy
• Active & peculiar galaxies
• Astrophysical jets
• Astrophysical electromagnetic fields
• Composition of astronomical objects
• Electromagnetic radiation astronomy
• Numerical simulations in gravitation & astrophysics