Together with described circuits for formation of microwave and mm-wave
oscillations with heterodyne-mixing, one may use the mode of mutual synchronization of two laser diodes (LD1 and LD2). In this case, the optical frequencies
difference is the final formed oscillation frequency, for instance, 10 GHz. For
synchronization of these laser diodes LD1 and LD2 we can use either the continuous
Fig. 2.20 Formation of RF oscillation of 10 and 89 GHz in the synthesizer with the optical microresonator (a) in the optical frequency synthesizer on the base of optical frequency synthesizer with
micro-toroid (b) using the nonlinear optical conversion. The optical emission spectrum at the output
of the optical circular resonator of the micro-toroid (c). Components of the pumping laser and
optical harmonics are shown (wavelength is 1570 nm). The difference of wavelengths between
adjacent harmonics is about 0.71 nm (which corresponds to frequency difference of adjacent
harmonics of about 85.7 GHz) [78]
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2 Nanostructural Optoelectronic Oscillators with the Fiber-Optical Delay Line