基于FPGA的光学相控阵驱动电路的设计与实现

Design and implementation of optical phased array driver circuit based on FPGA

传统的恒流源电路通常存在电路结构复杂、成本高等问题,满足不了一些高精度的应用要求。因此,结合实际工程的需要,设计并实现了一种基于现场可编程逻辑门阵列(FPGA)以及反馈调节算法的恒流源驱动电路,主要用于光学相控阵的相控单元控制。整个电路主要由FPGA控制模块、DAC模块、ADC模块、ADG模块以及采样电阻组成。通过FPGA接收调控参数,控制DAC模块进行输出,同时ADC模块对输出进行采集,在FPGA内对采集的数据进行反馈调控,最终实现128通道的可控恒流输出。电流的调控范围为0~15 mA,调控的步长为0.05 mA,调控的精度可达0.02 mA,响应速度为1 ms。系统的性能测试数据表明:基于FPGA的光学相控阵驱动电路具有响应速度快、电流输出精度高的优点,可满足对光学相控阵相位驱动的要求。

The traditional constant current source circuit usually has the problems of complex circuit structure and high cost,which can not meet the application requirements of some high precision.Therefore,combined with the needs of practical engineering,this paper designs and implements a constant current source driver circuit based on FPGA and feedback regulation algorithm,which is mainly used for the phased unit control of optical phased array.The whole circuit is mainly composed of FPGA control module,DAC module,ADC module,ADG module and sampling resistance.The control parameters are received by FPGA,and the DAC module is controlled to output.At the same time,the ADC module collects the output and conducts feedback regulation on the collected data in FPGA.Finally,the 128-channel controllable constant-current output is realized.The control range of current is 0~15 mA,the control step is 0.05 mA,the control accuracy is 0.02 mA,and the response speed is 1ms.The system performance test data show that the optical phased array drive circuit based on FPGA has the advantages of fast response speed and high current output accuracy,which can meet the requirements of optical phased array phase drive.