微波宽带小步进频率源的研究

发布时间：2018-06-04 01:00

  本文选题：压控振荡器 + 频率合成　； 参考：《电子科技大学》2015年硕士论文

【摘要】：频率源几乎是所有微波测试测量,通信系统以及监控系统的关键部分,不论是在军用或是民用电子设备中都不可或缺。现代频率综合有多种多样的频率合成技术,可满足宽带宽,小步进,低相噪等各种指标的要求。针对不同电子设备的系统指标要求,频率源演变出很多不同的设计方法。随着雷达系统及通信系统性能的提升,对频率源的带宽、跳频时间、步进以及相位噪声这些指标有了更高的要求。本文讨论分析了宽带频率源合成技术,对频率合成的几种方案进行讨论。在传统振荡器的基础上对宽带压控振荡器进行了研究分析,最终利用分立元件设计了推挽结构的宽带压控振荡器和集电极压控振荡器,并对其进行比较。在推挽结构宽带VCO的基础上实现频率源的宽带宽,并使用锁相环结合DDS的混合频率合成方式来实现了频率源的小步进设计。经过对硬件系统的调试,最终使得系统满足设计要求。经过对不同方案的论证及各项指标的计算,最终采用的系统是由电源模块、宽带VCO和PLL+DDS以及功率调整模块四个硬件模块构成。其中硬件电源部分是为各模块提供所需电压,宽带VCO采用的是推挽型结构的压控振荡器,它能实现较宽的带宽以及较好的稳定性,PLL+DDS由宽带VCO构成的PLL级联DDS实现,而功率调整模块则是对最终的输出功率进行调整使其达到系统功率指标的要求。通过对系统的仿真、测试、调试后系统最终频率输出为1000MHz-1500MHz,频率分辨率为100Hz,在1500MHz输出时相位噪声为-80dBc/Hz@10kHz、-104dBc/Hz@100kHz;杂散≤-45dBc。
[Abstract]:Frequency source is an essential part of almost all microwave measurement, communication and monitoring systems, whether in military or civil electronic equipment. Modern frequency synthesis has a variety of frequency synthesis technology, which can meet the wide bandwidth, small step, low phase noise and other requirements. According to the system requirements of different electronic equipment, the frequency source evolves many different design methods. With the improvement of the performance of radar system and communication system, the bandwidth of frequency source, frequency hopping time, step and phase noise have higher requirements. This paper discusses and analyzes the technology of broadband frequency source synthesis, and discusses several schemes of frequency synthesis. Based on the traditional oscillator, the wideband voltage-controlled oscillator is studied and analyzed. Finally, a push-pull structure wideband voltage-controlled oscillator and a collector voltage-controlled oscillator are designed and compared using discrete elements. The wideband width of the frequency source is realized on the basis of the push-pull structure broadband VCO, and the small step design of the frequency source is realized by using the hybrid frequency synthesis method of PLL and DDS. After debugging the hardware system, finally make the system meet the design requirements. The system is composed of four hardware modules: power supply module, broadband VCO and PLL DDS and power adjustment module. The hardware power supply part provides the required voltage for each module, and the wideband VCO adopts a push-pull type voltage-controlled oscillator. It can realize wider bandwidth and better stability. PLL DDS is realized by PLL cascade DDS composed of wideband VCO. The power adjustment module is to adjust the final output power to meet the system power requirements. Through the simulation and test of the system, the final frequency output of the system is 1000MHz-1500MHz, the frequency resolution is 100Hz, the phase noise of the 1500MHz output is -80dBc / Hzr 10kHz / 104dBc / HzBc / HzBZ 100kHz; the spurious 鈮，

本文编号：1975073