超宽带小步进频率合成技术研究

【作者】 吴穹；

【导师】 鲍景富；

【作者基本信息】 电子科技大学 ， 电路与系统， 2011， 硕士

【摘要】 超宽带小步进频率合成器在微波测试和测量中起着极为重要的作用。随着电子设备的发展,对测试设备的性能也提出了更高的要求。理想的状况是设计一种超宽频率输出、极小频率步进、具有极快的跳频速度、大动态范围可调的功率输出、优良的相位噪声和杂散指标的频率合成器。为了实现超宽带小步进频率合成器,本文介绍了三种超宽带小步进频率合成器方案,选取DDS内插到锁相环内的方案实现整个课题。通过对方案频率分辨率、输出范围、相位噪声、杂散、输出功率等指标的论证,证实了该方案的可行性。方案论证中特别对超宽带小步进频率方案中的整数边缘杂散进行了原理分析,论证了DPLL+DDS混合频率合成方案在超宽带小步进频率合成器中对该杂散抑制的优势。利用YTO振荡器的超宽输出带宽,设计并实现了60MHz~6GHz频率步进为100Hz的频率合成器,输出功率+10dBm,相位噪声6GHz@10kHz为-89dBc/Hz时,全频段杂散优于-60dBc。整个频率合成器分为主环组件、频率扩展组件、ALC组件、控制板组件、电源板组件、YTO组件。采用分层控制结构,通过SPI接口实现了模块化控制的理念。可通过USB连接上位机以及面板键盘、旋钮控制的方式实现频率合成器的所有功能控制。整个设计基本达到了测试设备的要求。更多还原

【Abstract】 The ultra-wideband frequency synthesizer with fine resolution plays a key role of microwave test and measurement. With the development of the electronic equipments, it calls for advanced frequency synthesizer techniques in the test and measurement. The ideal synthesizer should have ultra-wideband, fine frequency resolution, Fast hopping ability, wide dynamic power output,excellent phase noise and spurs performance.This paper has introduced three methods of designing ultra-wideband frequency synthesizer,and chosen the DPLL+DDS to design the synthesizer. Then the feasibility of the plan is demonstrated by the calculation of the index. After the analysis of the integer boundary spurs,it proves the advantage of the plan in suppression of this spurs.A 60MHz~6GHz ultra-wideband synthesizer is designed with 100Hz resolution based on a broadband YTO. The synthesizer, which is composed of five modules such as main-loop module, frequency extension module,ALC module,control module,power module and YTO module, have realized +10dBm output, -89dBc/Hz@10kHz phase noise at 6GHz,and the spurs suppression is superior to -60dBc before the ALC module. Serial peripheral interface (SPI) is used in the control module to communicate with other modules. The synthesizer can be controlled by the panel board or a computer connected with the USB interface.更多还原