An acousto-optical filter with tunable polarization based on photonic crystal fibers is used to propose a method of optical modulation, from the modulation by positions of ultrashort pulses in the frequency domain (PPFDM) and the modulation in dual optical sideband simultaneously. So apply this method for generating optical logic gates. It can be shown that AND and OR logic gates can be obtained when a soliton of 55.5-fs time width is encrypted initially generating two bits of information by the modulation method proposed here. We analyzed the optical double-sideband PPFDM modulation for the pulses (bits), polarized in the two input modes, allowing a variation in the ε_cod encoding parameter for each pulse. One input pulse in relation to another is allowed a phase difference Δϕ  =  1.28π, because analyzing the frequency curve as a function of a phase variation, it is observed that it is in this phase that we obtain the most reliable logic gates.