Aiming at the requirement of generating the linearly chirped microwave signal with high frequency and large bandwidth, an approach based on cascaded MZM (Mach-Zehnder modulator) to generate linearly chirped microwave signal with highfrequency and large-bandwidth via frequency and bandwidth multiplication was proposed. From the theoretical analysis, the linearly chirped microwave signal with variable multiplication factor of the carrier frequency and bandwidth was generated by properly adjusting the direct current bias points and the modulation index of the cascaded MZM. On the basis of this, the corresponding simulations were performed on the optical system software platform. The linearly chirped microwave signals with the carrier frequency and bandwidth of 40 GHz, 15.07 GHz and 58.25 GHz or 19.5 GHz were generated from a 5 GHz or 2 GHz linearly chirped drive signal respectively. The simulation results verify the feasibility of the proposed approach and the superior compression of the generated signal.