面向5G毫米波通信系统的本振源设计与实现

[摘要] 针对5G毫米波通信系统对本振源频率、相位噪声、杂散抑制要求的提升，提出了一种结合ADF4002和2个ADF5355频率合成器芯片，可同时用于中频和射频电路的高性能本振源。该本振源为系统中频模块提供5.4 GHz的单音本振信号并且利用数控衰减器和放大器实现了输出功率可调，同时也利用ADF5355的锁相环（PLL）和倍频器为射频模块提供8.4～11.2 GHz宽频带宽、步进为100 MHz的可调频本振信号，最终通过硬件电路的设计与调试，以及单片机（SCM）控制程序的编写，实现了低相噪、低杂散的稳定频率源。

[关键词] 大规模多输入多输出（MIMO）；本振；锁相环；低相位噪声；频率可调

[Abstract] Aiming at the improvement of local frequency, phase noise and spur suppression requirements of 5G millimeter-wave communication system, a high-performance local oscillator source which can be used for both intermediate frequency (IF) and radio frequency (RF) circuits is proposed by combining ADF4002 and two ADF5355 frequency synthesizer chips. The local oscillator source provides a 5.4 GHz single-tone local oscillator signal for the system’s IF module and uses a digitally controlled attenuator and amplifiers to achieve adjustable output power. At the same time, the ADF5355 phase-locked loop (PLL) and frequency doubler are also used to provide the RF module with a frequency-adjustable local oscillator signal, which step is 100 MHz in the 8.4～11.2 GHz wideband. Through the design and debugging of the hardware circuit and the programming of the single chip micyoco (SCM) control program, a low frequency noise and low spurious stable frequency source is realized finally.

[Keywords] massive multiple-input multiple-output (MIMO); local oscillator; PLL; low phase noise; frequency adjustable