雷达高度计发射前普遍采用回波模拟器来进行定标,所以对回波模拟器的误差进行准确的定量分析是高度计发射前的必备工作。在介绍回波模拟器原理的基础上,对影响回波模拟器误差的频综单元性能、二次相位、幅相起伏、延迟等特性进行了分析,最终根据设计指标计算了回波模拟器的系统误差。结果表明回波模拟器自身的精度能够满足海洋二号(HY-2)雷达高度计发射前定标的需要。 Before the launch of the radar altimeter, the echo simulator was generally used for calibration. Therefore, the accurate quantitative analysis of the echo simulator error is necessary before the altimeter launches. Based on the introduction of the principle of echo simulator, the performance of the frequency synthesizer, quadratic phase, amplitude fluctuation and delay affecting the error of the echo simulator are analyzed. Finally, the echo simulator system error. The results show that the accuracy of echo simulator can meet the need of calibration before launch of HY-2 radar altimeter.