介绍了基于可编程逻辑门阵列(FPGA)的能量倍增器(SLED)相位翻转系统.该系统主要由微波IQ调制器、FPGA和高速DAC组成.在FPGA的控制下,DAC输出两路双极性脉冲电平信号,加载于调制器的IQ端,将微波连续波输入信号转变为4 μs脉冲输出信号,并且在3 μs时刻微波相位发生180°跳变.经测试,相位翻转精度为180°±2°,翻转相位的长期稳定度优于±0.5°;相位翻转系统驱动的6台SLED的输出功率增益均超过7 dB,最高达到7.54 dB,增益的长期稳定度达到±0.1 dB.

This paper introduces the phase reverse system designed for SLAC Energy Doubler (SLED) based on Field Programmable Gate Array (FPGA).The phase reverse system is composed of a microwave IQ vector modulator,a FPGA board with the high speed DAC unit.Modulated by the DAC output pulse signal,the IQ modulator transforms the RF CW input signal into 4 μs pulse output signal,whose phase is reversed to 180° at the moment of 3 μs.The test results show that the phase reversal accuracy is about 180°±2°,and the stability is better than ±0.5°.The RF power gains of six SLEDs are more than 7 dB,the maximum 7.54 dB is achieved.The long-term variation of the power gain is ±0.1 dB.