A novel scheme for the generation of background-free pulsed microwave signals is proposed and experimentally demonstrated based on spectral shaping, frequency-to-time mapping, and balanced photodetection. In the proposed scheme, the optical spectral shaper, which consists of a differential group delay (DGD) element, two polarization controllers, and a polarization beam splitter, has two outputs with complementary power transfer functions. By passing a short optical pulse through the spectral shaper and a dispersive element (DE), a pulsed microwave signal is obtained after balanced photodetection. Thanks to the balanced photodetection, the lowfrequency components (i.e., the background signal) in the electrical spectrum is suppressed, leading to the generation of a background-free pulsed microwave signal. Meanwhile, the spectral power of the obtained microwave signal is enhanced compared to that obtained by single-end detection. Experimental results for the generation of a pulsed microwave signal centered at 12.46 GHz show that the background signal can be suppressed by more than 30 dB, and the spectral power is increased by 5.5 dB. In addition, the central frequency of the obtained background-free pulsed microwave signal can be tuned by changing the DGD introduced by the DGD element, and/or by changing the dispersion of the DE.