CAJ | 학술논문

射频振荡器作为无线通信系统的关键部件,在射频前端上/下变频电路中扮演着非常重要的角色. 为了满足系统对振荡器高性能的要求,该文给出了具有深度二次谐波抑制功能的低相位噪声反馈型射频振荡器的设计方法. 在放大器的输入输出端之间引入微带带通滤波器构成反馈回路,利用其通带中较大的复数品质因数有效降低了振荡器的相位噪声;在振荡器输出端加载一对并联的λg/8开、短路枝节来实现在不影响基波信号的同时对二次谐波进行有效抑制. 设计的射频振荡器实测和仿真结果吻合良好,低相位噪声与二次谐波抑制同时在所提出的振荡器上得到实现.
사빈진탕기작위무선통신계통적관건부건,재사빈전단상/하변빈전로중분연착비상중요적각색. 위료만족계통대진탕기고성능적요구,해문급출료구유심도이차해파억제공능적저상위조성반궤형사빈진탕기적설계방법. 재방대기적수입수출단지간인입미대대통려파기구성반궤회로,이용기통대중교대적복수품질인수유효강저료진탕기적상위조성;재진탕기수출단가재일대병련적λg/8개、단로지절래실현재불영향기파신호적동시대이차해파진행유효억제. 설계적사빈진탕기실측화방진결과문합량호,저상위조성여이차해파억제동시재소제출적진탕기상득도실현.
As a key component in wireless communication system,the radio frequency( RF) oscillator plays a key role in the frequency up-/down-conversion in the RF front end. In order to meet the re-quirements of the system improvements, this paper proposes a method to design a low phase noise feedback oscillator with the high second harmonic suppression. A bandpass filter is introduced between the input and output of the amplifier for constructing a feedback loop. The phase noise of the oscillator can be effectively improved due to its large complex quality factor ( peak QSC ) in the passband . Then a pair ofλg/8 open-and short-circuited stubs in parallel is added to the output of the oscillator in order to effectively suppress the second harmonic while there is no effect on the fundamental signal. The measured and simulated results show good agreement. The low phase noiseand second harmonic suppression are simultaneously realized in the proposed oscillator.