Carrier suppressed single sideband (SSB) modulation is a special form of amplitude modulation, which can suppress the carrier and another side band to improve the frequency band utilization rate and increase the transmission capacity of optical fiber. The dispersion can be suppressed effectively and the transmission distance of the signal can be extended. So it is widely used in long distance high frequency microwave radio over fiber (ROF) system. The principle of using commercial LiNbO3 modulator to generate carrier suppressed SSB signals is analyzed in detail, and based on this, a testing system is built to generate carrier suppressed SSB signals of order ±1 respectively, +1 for long wave direction and -1 for short wave direction.