低频射电波段（10～250 MHz）是新的重要观测波段和研究窗口，将带来新的发现和理论研究挑战。欧美等国正在发展LOFAR、LWA和MWA等低频射电项目，SKA也将低频纳入其观测范围，充分印证了低频射电波段的重要性。 在本文中，首先简述低频射电望远镜系统的组成和各个部分的作用。考虑到低频段的天空背景噪声比较强、干扰信号多种多样的情况，制订了接收机的总体方案，要求有大的动态范围和一定的抗干扰能力。接收机采用直接采样的设计结构，由巴伦、滤波器和放大器三部分组成。并根据巴伦、滤波器和放大器的设计原理与方法设计出合理的器件，并最终组成工作在30～65 MHz的模拟接收机。利用实验室的设备测量得到接收机主要技术参数，其增益G=60 dB、输入1 dB压缩点IP1dB=-40 dBm和输入3阶互调点IIP3=-23.09 dBm，满足双极化半波振子天线阵的需求。 最终接收机将会被安装在一个2*2双极化半波振子天线阵上，首先用于观测太阳在低频段的射电爆发。; Low-frequency radio band(10～250 MHz) is a new important observed band and researchful window, that will lead to new discoveries and research challenges of theories. Europe、USA and other countries are developing low-frequency radio project, such as LOFAR、LWA and MWA. SKA will be used to observe the low frequency sky. All these radio telescopes demonstrate the importance of low frequency band. This thesis describes the components of radio telescope and the function of each part. Considering the strong sky background noise in low frequency and various interference, we formulate the overall scheme of the receiver, which requires a large dynamic range and certain anti-interference ability. At last , receiver is designed to be a direct sample structure and consists of balun、filter and amplifier. According the principles and methods of balun、filter and amplifier, we design every component of receiver and achieve a receiver which works in the 30 to 65 MHz band. We measure the main performance parameters of the receiver with the equipment in the laboratory: G=60 dB、IP1dB=-40 dBm and IIP3=-23.09 dBm. These receiver’s parameters meet the requirement of half-wave dipolar antenna array . The receiver will be installed in the 2*2 half-wave dipolar antenna array and used to observe the solar burst in the low frequence band at first.
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