【摘要】 扫频信号源是输出频率可数控步进调整的正弦波信号源。低相位噪声和杂散的高频谱纯度扫频信号源是组成雷达接收机和系统频域分析设备等的核心。文中以数字锁相环技术(DPLL)作为高频谱纯度信号输出核心，用分频寄存器的设置来控制信号的输出频率，并通过高阶滤波器和自动增益系统得到最终的扫频信号输出频率。电路中，基于ADF4002数字鉴频鉴相器芯片、MC12148压控振荡器芯片和无源滤波器电路构建数字锁相环，再通过VCA821实现自动增益控制电路，最终实现高频谱纯度扫频信号源。经测试，该扫频信号源能在40～120MHz范围实现较高频谱纯度的扫频信号输出，将DPLL技术应用于扫频信号源不但易于变频和加快扫频源的迭代，而且大幅度降低了硬件开发成本。更多还原

【Abstract】 The swept frequency signal source is a sine wave signal source whose output frequency can be adjusted by numerical control steps. High frequency spectral purity sweep signal source is one of the core components to realize radar receiver and system frequency domain analysis equipment. In this paper, digital phase locked loop(DPLL) technology is used as the output core of high-frequency spectral purity signal. The output frequency of the signal is controlled by setting the frequency division register, and the final output frequency of the swept signal is obtained by high-order filter and automatic gain system. In the circuit, a digital phase-locked loop is constructed based on ADF4002 digital frequency and phase discriminator chip, MC12148 voltage controlled oscillator chip and passive filter circuit, and then the automatic gain control circuit is realized by VCA821, and finally the high-frequency spectrum purity sweep signal source is realized. After testing, the swept frequency signal source can realize the sweep signal output with high spectral purity in the frequency range of 40～120 MHz. The application of DPLL technology to the sweep signal source is not only easy to convert frequency and speed up the iteration of the sweep source, but also greatly reduces the cost of hardware development.更多还原