文章基于受激布里渊散射增益补偿技术，对微波光子滤波器的波长特性进行研究，并提出了一种改进方法。若将受激布里渊散射的一个增益谱与两个损耗谱相互叠加，可实现波长选择及带宽可调。通过计算，可以使带宽从20 MHz减小到3.8 MHz，减小了81%，而选择性提高了5倍多。在一些特殊应用领域，对滤波器进行级联，可使带宽进一步减小。通过这种方法，使带宽从13 MHz减小到了2.5 MHz，减小了80.8%，选择性进一步得到提高。经过仿真及实验，证明了这种方法是切实可行的。

Based on gain compensation of stimulated Brillouin scattering, we study the wavelength characteristics improvement of microwave photonic filter and propose an improved method in this paper. If the gain spectrum of stimulated Brillouin scattering is overlapped with two loss spectra, the wavelength selectivity and bandwidth tunability can be achieved. Through calculation, the bandwidth is reduced from 20 MHz to 3.8 MHz, which reduced by 81% and wavelength selectivity is increased by 5 times. In some special fields, the bandwidth can be further reduced through the cascade of filters. In this way, the bandwidth can be reduced from 13 MHz to 2.5 MHz, which reduced by 80.8%, and wavelength selectivity is further improved. Through simulation and experiment, it is proved that the method is practical and feasible.