-
摘要:
为了使微波光子滤波器兼具宽调谐范围与高频率选择性,本文基于窄线宽单纵模光纤受激布里渊振荡器首次提出并验证了一种具有宽调谐范围、窄滤波带宽特性的微波光子滤波器。该滤波器的核心是腔长为10 m的布里渊光纤振荡器,受激布里渊散射泵浦光与光载波信号分别由两个不同的可调谐激光器提供,布里渊增益与光调制信号相互作用后,利用该布里渊光纤振荡器压缩光谱线宽,实现窄带微波光子滤波;通过简单地改变泵浦光波长,实现滤波器通带大范围稳定调谐。实验结果表明,该微波光子滤波器在0~20 GHz的频率范围内可稳定调谐,带外抑制比约为20 dB,其3-dB带宽和最大
Q 值分别为6.2 kHz和3.222×106。本文提出的单通带微波光子滤波器不仅具有目前已知的最高Q 值,同时具有宽可调性、高带外抑制和结构简单等优势。-
关键词:
- 受激布里渊散射(SBS) /
- 微波光子滤波器(MPF) /
- 宽调谐 /
- 带外抑制比 /
- 窄带宽
Abstract:In order to make sure a microwave photonic filter both have wide tuning range and high frequency selectivity, a microwave photonic filter with a wide tuning range and narrow filter bandwidth based on a Brillouin oscillator is proposed and verified for the first time. The core of the filter is a Brillouin fiber oscillator with a cavity length of 10 m, and the stimulated Brillouin scattering pump and optical carrier signal are provided by two different tunable lasers. After the Brillouin gain spectrum interacts with the optical modulation sideband, the Brillouin fiber oscillator is used to narrow the spectral linewidth to realize narrowband microwave photonic filtering. By changing the pump wavelength, the filter passband can be tuned stably. The experimental results show that the microwave photonic filter can be stably tuned in the frequency range of 0−20 GHz. The out-of-band rejection ratio is found to be about 20 dB, and its 3-dB bandwidth and maximum
Q value are 6.2 kHz and 3.222×106, respectively.To the best of our knowledge, this is the highest value of a high-Q single-passband MPF reported to date. At the same time, the MPF has the advantages of wide tunability, high side mode suppression and a simple structure. -
图 1 MPF的实验装置。TLS,可调谐激光器;PC,偏振控制器;PM,相位调制器;OC,光耦合器;SMF,单模光纤;EDFA,掺铒光纤放大器;Cir,光环形器;PD,光电探测器;OSA,光谱分析仪;VNA,矢量网络分析仪
Figure 1. Experimental setup of MPF. TLS, tunable laser; PC, polarization controller; PM, phase modulator; OC, optical coupler; SMF, single-mode fiber; EDFA, erbium-doped fiber amplifier; Cir, optical circulator; PD, photodetector; OSA , spectrum analyzer; VNA, vector network analyzer
图 2 可调谐窄带MPF原理示意图。(a)双边带扫频调制光信号光谱;(b)SBS光谱;(c)利用SBS放大DSB调制信号上边带;(d)环形腔R1的FSR响应;(e)MPF滤波通带响应
Figure 2. Illustration of tunable narrowband MPF principle. (a) Optical spectra of double sideband swept frequency modulated signal. (b) Optical spectra of SBS. (c) Amplification of the upper sideband of a DSB modulated signal using SBS gain. (d) FSR response of single-ring cavity R1. (e) Response of MPF
-
[1] YAO J P. Microwave photonics[J]. Journal of Lightwave Technology, 2009, 27(3): 314-335. doi: 10.1109/JLT.2008.2009551 [2] CHEN T, YI X K, LI L W, et al. Single passband microwave photonic filter with wideband tunability and adjustable bandwidth[J]. Optics Letters, 2012, 37(22): 4699-4701. doi: 10.1364/OL.37.004699 [3] KHILO A, SPECTOR S J, GREIN M E, et al. Photonic ADC: overcoming the bottleneck of electronic jitter[J]. Optics Express, 2012, 20(4): 4454-4469. doi: 10.1364/OE.20.004454 [4] 陶源盛, 王兴军, 胡薇薇. 硅基微波光子滤波器的研究进展[J]. 半导体光电,2021,42(1):1-10.TAO Y SH, WANG X J, HU W W. Recent progresses of silicon integrated microwave photonic filters[J]. Semiconductor Optoelectronics, 2021, 42(1): 1-10. (in Chinese) [5] 吴妮珊, 夏历. 基于微波光子学的准分布式光纤传感解调技术[J]. 中国光学,2021,14(2):245-263. doi: 10.37188/CO.2020-0121WU N SH, XIA L. Interrogation technology for quasi-distributed optical fiber sensing systems based on microwave photonics[J]. Chinese Optics, 2021, 14(2): 245-263. (in Chinese) doi: 10.37188/CO.2020-0121 [6] 余晓畅, 许雅晴, 蔡佳辰, 等. 可调微纳滤波结构的研究进展[J]. 中国光学,2021,14(5):1069-1088. doi: 10.37188/CO.2021-0044YU X CH, XU Y Q, CAI J CH, et al. Progress of tunable micro-Nano filtering structures[J]. Chinese Optics, 2021, 14(5): 1069-1088. (in Chinese) doi: 10.37188/CO.2021-0044 [7] 王文轩, 陶继, 黄龙. 基于光注入法布里-珀罗激光器的窄带可调谐微波光子滤波器[J]. 中国激光,2017,44(10):1006002. doi: 10.3788/CJL201744.1006002WANG W X, TAO J, HUANG L. Narrowband tunable microwave photonic filter based on Fabry-Perot laser with optical injection[J]. Chinese Journal of Lasers, 2017, 44(10): 1006002. (in Chinese) doi: 10.3788/CJL201744.1006002 [8] 胡总华, 聂奎营, 阮毅, 等. 基于色散光纤环级联结构的可调谐带通微波光子滤波器[J]. 半导体光电,2019,40(2):189-192,199.HU Z H, NIE K Y, RUAN Y, et al. Bandpass-tunable microwave photonic filter based on dispersion fiber loops with cascaded structure[J]. Semiconductor Optoelectronics, 2019, 40(2): 189-192,199. (in Chinese) [9] GAO L, CHEN X F, YAO J P. Tunable microwave photonic filter with a narrow and flat-top passband[J]. IEEE Microwave and Wireless Components Letters, 2013, 23(7): 362-364. doi: 10.1109/LMWC.2013.2262263 [10] ZHANG T T, XIONG J T, ZHENG J L, et al. Wideband tunable single bandpass microwave photonic filter based on FWM dynamics of optical-injected DFB laser[J]. Electronics Letters, 2016, 52(1): 57-59. doi: 10.1049/el.2015.1696 [11] 张梓平, 牛哓晨, 黄杰, 等. 基于光纤环谐振腔的高性能微波光子滤波器[J]. 光学学报,2020,40(21):2106001. doi: 10.3788/AOS202040.2106001ZHANG Z P, NIU X CH, HUANG J, et al. High-performance microwave photonic filter based on fiber ring resonator[J]. Acta Optica Sinica, 2020, 40(21): 2106001. (in Chinese) doi: 10.3788/AOS202040.2106001 [12] 严艺, 廖同庆, 吕晓光, 等. 新型多抽头复系数微波光子滤波器[J]. 红外与激光工程,2019,48(1):0120001. doi: 10.3788/IRLA201948.0120001YAN Y, LIAO T Q, LU X G, et al. Novel multitap complex coefficient microwave photonic filter[J]. Infrared and Laser Engineering, 2019, 48(1): 0120001. (in Chinese) doi: 10.3788/IRLA201948.0120001 [13] WANG W T, LIU J G, MEI H K, et al. Microwave photonic filter with complex coefficient based on optical carrier phase shift utilizing two stimulated Brillouin scattering pumps[J]. IEEE Photonics Journal, 2015, 7(1): 1-8. [14] JIANG H Y, YAN L SH, PAN W, et al. Ultra-high speed RF filtering switch based on stimulated Brillouin scattering[J]. Optics Letters, 2018, 43(2): 279-282. doi: 10.1364/OL.43.000279 [15] 张卫华, 张丽丽, 曹晔. 基于受激布里渊散射的微波光子滤波器[J]. 南开大学学报(自然科学版),2014,47(1):55-60.ZHANG W H, ZHANG L L, CAO Y. Microwave photons filter based on stimulated Brillouin scattering[J]. Acta Scientiarum Naturalium Universitatis Nankaiensis, 2014, 47(1): 55-60. (in Chinese) [16] 徐翌明, 潘炜, 卢冰, 等. 基于受激布里渊散射的多阻带微波光子滤波器[J]. 中国激光,2018,45(11):1106004. doi: 10.3788/CJL201845.1106004XU Y M, PAN W, LU B, et al. Multi-stopband microwave photonic filter based on stimulated Brillouin scattering[J]. Chinese Journal of Lasers, 2018, 45(11): 1106004. (in Chinese) doi: 10.3788/CJL201845.1106004 [17] WANG T, XIAO J L, WU J L, et al. Dual-passband microwave photonic filter based on a directly modulated microcavity laser[J]. IEEE Photonics Technology Letters, 2021, 33(4): 185-188. doi: 10.1109/LPT.2021.3050818 [18] LI ZH K, ZHANG ZH Y, ZENG ZH, et al. Tunable dual-passband microwave photonic filter with a fixed frequency interval using phase-to-intensity modulation conversion by stimulated Brillouin scattering[J]. Applied Optics, 2019, 58(8): 1961-1965. doi: 10.1364/AO.58.001961 [19] ZENG ZH, ZHANG ZH Y, LI ZH K, et al. Freely tunable dual-passband microwave photonic filter based on phase-to-intensity modulation conversion by stimulated Brillouin scattering[J]. IEEE Photonics Journal, 2019, 11(1): 5501009. [20] WEN H SH, LI M, LI W, et al. Ultrahigh-Q and tunable single-passband microwave photonic filter based on stimulated brillouin scattering and a fiber ring resonator[J]. Optics Letters, 2018, 43(19): 4659-4662. doi: 10.1364/OL.43.004659 [21] WEN H SH, XU B R, ZHAI K P, et al. Ultrahigh spectral resolution single passband microwave photonic filter[J]. Optics Express, 2021, 29(18): 28725-28740. doi: 10.1364/OE.436173 [22] KURASHIMA T, HORIGUCHI T, TATEDA M. Thermal effects of Brillouin gain spectra in single-mode fibers[J]. IEEE Photonics Technology Letters, 1990, 2(10): 718-720. doi: 10.1109/68.60770 [23] NICATI P A, TOYAMA K, HUANG S, et al. Temperature effects in a Brillouin fiber ring laser[J]. Optics Letters, 1993, 18(24): 2123-2125. doi: 10.1364/OL.18.002123 [24] 刘毅, 于晋龙, 王红杰, 等. 基于反馈光纤环的可调多波长布里渊掺铒光纤激光器[J]. 中国激光,2014,41(2):0202003.LIU Y, YU J L, WANG H J, et al. Tunable multiwavelength brillouin-erbium fiber laser based on feedback fiber loop[J]. Chinese Journal of Lasers, 2014, 41(2): 0202003. (in Chinese) [25] 黄海碧, 刘文杰, 孙粤辉, 等. 高超噪比宽带毫米波噪声信号光子学产生研究[J]. 中国光学,2022,15(2):251-258. doi: 10.37188/CO.2021-0158HUANG H B, LIU W J, SUN Y H, et al. Photonics generation of broadband millimeter wave noise signals with high excess noise ratios[J]. Chinese Optics, 2022, 15(2): 251-258. (in Chinese) doi: 10.37188/CO.2021-0158