海洋二号（HY-2A）卫星是我国首颗海洋动力环境卫星，微波辐射计是该星的4个微波载荷之一，主要用于测量全球海洋表面温度、海面风速、海洋上空水汽和降雨等参数。HY-2A微波辐射计采用圆锥扫描方式，使用冷空反射器和星载热定标源完成在轨两点定标，覆盖频率范围为6~37 GHz，本文对系统、天线、接收通道和配平设计进行了介绍。

HY-2A satellite is China's first ocean dynamic environment satellite. The microwave radiometer is one of the four microwave payloads of the satellite, which is mainly used for measuring parameters including sea surface temperature, wind speed, water vapor and liquid water etc. The microwave radiometer is a conical scanning radiometer, real time calibration with cold sky and warm load on board, cover frequency from 6 GHz to 37 GHz. This paper introduced the design of instrument including system design, antenna design, receiver design and balance design etc.