摘要
编写了P89LPC938单片机程序和MATLAB程序,来控制Hittite公司宽带频率合成芯片HMC833LP6GE.MATLAB程序通过RS232接口和单片机对HMC833LP6GE寄存器进行读写.用Agilent频谱仪观测HMC833LP6GE输出信号的频谱特性.改变HMC833LP6GE内部众多寄存器的内容,分析HMC833LP6GE锁相环的锁存状态、频率的杂散特性以及增益与输出功率的关系.实验表明,HMC833LP6GE数据手册推荐的自动校准方式在实际使用时并不理想,锁相环不易锁存.本文的方法是,在整个VCO频率范围（1 500～3 000 MHz）内逐点改变频率,找到保证锁相环锁存的最佳寄存器数据并保存起来,建立寄存器内容和VCO频率的函数关系,实现手动校准方式.这种方法不但能够保证任何频率下锁存,而且提高了锁存速度,在随机频率跳变下也能完全锁存.HMC833LP6GE的内部寄存器可以控制输出,通过实验找出了最佳的功率频率关系.另外,关于电荷泵电流对杂散的影响也做了讨论.
This paper writes P89LPC938 program and MATLAB program,to control wideband frequency synthesis chip HMC833LP6GE of Hittite Cooperation.MATLAB program reads and writes the HMC833LP6GE register through the RS232 interface and single chip microcomputer.Agilent spectrum analyzer is used to observe the spectral characteristics of the HMC833LP6GE output signal.By changing the contents of the HMC833LP6GE internal registers,different analysis are performed on the latch state of HMC833LP6GE phase-locked loop,and the frequency spurious characteristic,as well as the relationships between gain and output power.Experiments show that the automatic calibration approach recommended by the HMC833LP6GE data sheet is not ideal in the real practice,while the PLL is not easy to latch.The paper introduces a manual calibration method,which not only finds and preserves the best register data for the PLL latch,by changing the frequency point by point under the VCO frequency range （1 500～3 000 MHz）,but also builds the relationship between register contents and the frequency of VCO.This method can ensure all locking under any frequencies and improve the latch speed,as well as fulfill completely latch in randomly hopping frequency.The internal registers of the HMC833LP6GE can control the output,and we find the optimum relationship between output power and frequency through the experiments.Besides,the effect of the charge pump current on the spurious is also issued at the end part.
出处
《电子测量技术》
2014年第5期47-51,共5页
Electronic Measurement Technology
基金
上海市重点学科及实验室(S30108
08DZ2231100)基金项目
