一种Ku波段接收机的研制
发布时间：2018-10-31 18:14
【摘要】：当前在全球范围内,雷达系统已经广泛地使用于陆、海、空和地球外层空间。雷达技术和电子对抗技术发展日新月异,雷达系统及其工作环境越来越复杂,要求雷达具有较强的抗干扰能力,因此,作为雷达的关键部分,接收机的设计要求被提得越来越高。设计雷达接收机,不仅需要考虑被探测目标的信号,还需要考虑探测提取过程中出现的各种噪声和干扰。接收机前端的性能指标对雷达系统有显著的影响,伴随微波技术的发展,元器件的指标和制造工艺水平有极大飞跃,为提高接收机的集成度创造了条件,尤其是为减小接收机前端的体积提供了支持。将接收机前端压缩到较小体积,顺应雷达系统的小型化趋势。本文介绍了几种雷达接收机的工作模式,最终采用超外差方式设计接收机,超外差式接收机主要包含了接收机前端、频率源和中频放大电路等部分。文章主要对超外差接收机的原理进行分析,分别阐述了限幅器、低噪声放大器、滤波器、混频器、频率源在接收机中的原理和作用,提出了设计方案并加以仿真及实现。在设计中采用的中频部分电路较为简单,不做详细描述。在接收机的前端中,限幅器在最靠前的位置,保护低噪声放大器在大信号到来时不被烧毁;低噪声放大器的作用至关重要,决定了噪声系数等关键指标;为降低噪声系数,将MEMS滤波器设置在低噪声放大器之后,起到抑制带外杂波的作用;第一级混频器将15.5±0.5GHz的射频信号变为2.5±0.5GHz,第二级混频器将2.5±0.5GHz的射频信号变为0.15GHz,得到中频输出信号;频率源要求提供两路射频输出,分别作为一本振和二本振,一本振的频率为13GHz,二本振的频率为2.35±0.5GHz。在各章节之后列出了关键器件的测试结果,与预期指标进行对比和说明。本文实现的超外差雷达接收机,达到了接收机任务的技术指标,不仅具有高灵敏度、低噪声系数、信号选择性好及工作性能稳定等特点,还突破了以往的模块化设计,实现了符合工程需要的高集成度、小体积的接收机,符合了雷达系统的小型化趋势。
[Abstract]:At present, radar systems are widely used in land, sea, air and outer space around the world. With the rapid development of radar technology and electronic countermeasure technology, radar system and its working environment are becoming more and more complex, which requires radar to have strong anti-jamming capability. Therefore, as a key part of radar, The design requirements of the receiver are getting higher and higher. To design a radar receiver, not only the signal of the target to be detected, but also all kinds of noise and interference in the detection and extraction process should be considered. The performance index of the front end of the receiver has a remarkable influence on the radar system. With the development of microwave technology, the index of components and the manufacturing technology have made a great leap forward, which has created conditions for improving the integration of the receiver. In particular, support is provided for reducing the volume of the front end of the receiver. The receiver front end is compressed to a smaller volume, following the trend of radar system miniaturization. In this paper, several working modes of radar receiver are introduced. Finally, the superheterodyne receiver is designed. The superheterodyne receiver mainly includes the front end of the receiver, the frequency source and the if amplifier circuit. In this paper, the principle of superheterodyne receiver is analyzed, and the principle and function of limiter, low noise amplifier, filter, mixer and frequency source in the receiver are expounded, and the design scheme is put forward and simulated and realized. The if circuit used in the design is simple and not described in detail. In the front end of the receiver, the limiter is in the front position to protect the low noise amplifier from being destroyed when the large signal arrives, and the function of the low noise amplifier is very important, which determines the key index such as noise coefficient, and so on. In order to reduce the noise coefficient, the MEMS filter is set behind the low noise amplifier to suppress the out-of-band clutter. In the first stage, the RF signal of 15.5 卤0.5GHz is changed into 2.5 卤0.5 GHz, the second stage mixer changes the 2.5 卤0.5GHz RF signal to 0.15 GHz, and the intermediate frequency output signal is obtained. The frequency source is required to provide two RF outputs, one oscillator and two oscillator, the frequency of one oscillator is 13 GHz, and the frequency of local oscillator is 2.35 卤0.5 GHz. After each chapter, the test results of the key devices are listed, and compared with the expected indicators. The superheterodyne radar receiver realized in this paper not only has the characteristics of high sensitivity, low noise coefficient, good signal selectivity and stable working performance, but also breaks through the previous modular design. The high integration and small volume receiver are realized, which accord with the trend of radar system miniaturization.
【学位授予单位】：电子科技大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TN965.5
，
本文编号：2303135
[Abstract]:At present, radar systems are widely used in land, sea, air and outer space around the world. With the rapid development of radar technology and electronic countermeasure technology, radar system and its working environment are becoming more and more complex, which requires radar to have strong anti-jamming capability. Therefore, as a key part of radar, The design requirements of the receiver are getting higher and higher. To design a radar receiver, not only the signal of the target to be detected, but also all kinds of noise and interference in the detection and extraction process should be considered. The performance index of the front end of the receiver has a remarkable influence on the radar system. With the development of microwave technology, the index of components and the manufacturing technology have made a great leap forward, which has created conditions for improving the integration of the receiver. In particular, support is provided for reducing the volume of the front end of the receiver. The receiver front end is compressed to a smaller volume, following the trend of radar system miniaturization. In this paper, several working modes of radar receiver are introduced. Finally, the superheterodyne receiver is designed. The superheterodyne receiver mainly includes the front end of the receiver, the frequency source and the if amplifier circuit. In this paper, the principle of superheterodyne receiver is analyzed, and the principle and function of limiter, low noise amplifier, filter, mixer and frequency source in the receiver are expounded, and the design scheme is put forward and simulated and realized. The if circuit used in the design is simple and not described in detail. In the front end of the receiver, the limiter is in the front position to protect the low noise amplifier from being destroyed when the large signal arrives, and the function of the low noise amplifier is very important, which determines the key index such as noise coefficient, and so on. In order to reduce the noise coefficient, the MEMS filter is set behind the low noise amplifier to suppress the out-of-band clutter. In the first stage, the RF signal of 15.5 卤0.5GHz is changed into 2.5 卤0.5 GHz, the second stage mixer changes the 2.5 卤0.5GHz RF signal to 0.15 GHz, and the intermediate frequency output signal is obtained. The frequency source is required to provide two RF outputs, one oscillator and two oscillator, the frequency of one oscillator is 13 GHz, and the frequency of local oscillator is 2.35 卤0.5 GHz. After each chapter, the test results of the key devices are listed, and compared with the expected indicators. The superheterodyne radar receiver realized in this paper not only has the characteristics of high sensitivity, low noise coefficient, good signal selectivity and stable working performance, but also breaks through the previous modular design. The high integration and small volume receiver are realized, which accord with the trend of radar system miniaturization.
【学位授予单位】：电子科技大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TN965.5
，
本文编号：2303135
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