摘要
提出一种基于相干光处理的微波信道化接收机,采用自由谱范围（FSR）不同的两套光频率梳（OFC,optical frequency combs）分别作为光载波和光本振,使得各个信道的输出具有相同的中频。本文方法将微波信号调制到载波OFC的每一个频率分量上,并用法布里-珀罗（F-P）光滤波器对多个信道的调制光边带同时进行带通滤波,然后与本振OFC进行相干探测实现频率下转换。若载波OFC比本振OFC的FSR大于1个信道带宽,并使F-P滤波器的FSR与本振OFC相等,可得到等带宽、等中频的微波信道,降低了后续电路的复杂度。对两个相邻信道进行了实验,将9.74-9.86GHz和9.86-9.98GHz波段的信号分别下转换到两个带宽为120MHz的中频信道,两个中频信道的中心频率仅相差4 MHz分别为900 MHz和896 MHz,表明本文方法能够实现等中频的信道输出。
An RF channelizer based on coherent optical processing is proposed. By employing two optical frequency combs （OFCs） with different free spectral ranges （FSRs） as optical carriers and optical local oscillators respectively, the channelizer can translate all of the frequency channels to a common intermediate frequency （IF）. The microwave signal is modulated on every optical carrier,and then all the modu- lated optical sidebands are filtered by an FP optical filter. Finally, the filtered optical sidebands are coherently detected with the optical local oscillators, and the frequency down-conversion can be achieved. As the FSR of the carrier OFC is a channel bandwidth larger than that of the local OFC,and the FSR of the FP filter is equal to that of the local OFC, the channel of common IF and bandwidth can be realized. Therefore,it is convenient for electronic circuits design. Experiment measurements are demonstrated by translating two adjacent frequency-hand ranges over 9.7-9.86 GHz and 9.86-9.98 GHz into a 120 MHz IF bandwidth. The center frequencies of two channels are 900 MHz and 896 MHz, respectively with merely 4 MHz frequency difference. It is indicated that a common IF channel can be accomplished by this method.
出处
《光电子．激光》
EI
CAS
CSCD
北大核心
2014年第12期2294-2299,共6页
Journal of Optoelectronics·Laser
关键词
光纤光学
微波光子学
光子下变频
光滤波链路
微波信道化
fiber optics
microwave photonics
photonic down-conversion
optically filtered link
microwave channelization
