Method for generating ultra-wideband multi-band frequency microwave signal

The invention discloses a method for generating an ultra-wideband multi-band frequency microwave signal. The method comprises the following steps that a laser diode (LD) is taken as an input light source, an optical signal of the laser diode is averagely divided into two parts by an optical power splitter, and the two parts are respectively injected into a first frequency modulator (FM1) and a second frequency modulator (FM2) to carry out frequency modulation; the first frequency modulator (FM1) and the second frequency modulator (FM2) are respectively driven by a first radio-frequency signal (RF1) with the frequency of f1 and a second radio-frequency signal (RF2) with the frequency of f2, so that a first optical frequency comb (OFC1) with the frequency space of f1 and a second optical frequency comb (OFC2) with the frequency space of f2 are generated; and the two optical frequency combs are injected together through a coupler, and after frequency mixing, the ultra-wideband multi-band frequency microwave signal with the frequency space of deltaf=absolute value of f1-f2 is generated through beat frequencies of the optical frequency combs. The ultra-wideband multi-band frequency microwave signal which is generated based on the beat frequencies of the optical frequency combs has advantages on the spectral bandwidth and the frequency component, and the frequency space is tunable.