Abstract: In the nuclear signal readout method of optical phase modulation, the detector signal is modulated into optical phase to be transmitted along an optical fiber. In this readout scheme, the Modulation Driver Module, which generates and amplifies the carrier signal, plays an important role in the readout electronics. In order to generate high and adjustable amplitude carrier signals with low phase noise, this paper proposes a carrier generation and amplification method based on PLL and MMIC RF amplifier respectively, which has adventages of simple structure, small size and excellent performance. To evaluate this method, the loop filter for the carrier generation circuit is designed and simulated with the ADIsimPLL simulation software. Meanwhile, the carrier amplification circuit is designed and simulated with the ADS simulation software. Furthermore, test results show that the phase noise of the output carrier signal with 26 dBm amplitude is better than –110 dBc/Hz@ 100 kHz, which can be used for signal demodulation well.