- 标题
- 摘要
- 关键词
- 实验方案
- 产品
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Large-Dynamic Frequency Response Measurement for Broadband Electro-Optic Phase Modulators
摘要： A novel method for characterizing the frequency responses of broadband electro-optic phase modulators (PMs) by employing stimulated Brillouin scattering (SBS) is proposed and experimentally demonstrated. In the proposed method, the SBS amplifies the +1st-order sideband and attenuates the -1st-order sideband of the phase-modulated signal from a PM under test. Thereby, the phase-modulated signal is converted into an optical single-sideband (OSSB) modulation signal. After square-law photodetection, the overall frequency responses are obtained. Removing the frequency responses of the SBS gain and the photodetector (PD) from the overall responses, the responses of the PM are thus achieved. Benefitting from the amplification of the SBS, the proposed method possesses a large dynamic range. Sub-Hz resolution and broadband measurement range are also achievable. A commercial broadband PM is experimentally characterized from 10 MHz to 50 GHz with a resolution of 5 MHz. According to the amplification of the SBS, the dynamic range is enhanced by 17.74 dB. The measurement result is verified by the conventional method utilizing optical spectrum analysis.
关键词： stimulated Brillouin scattering,Electrooptic modulation,Phase modulation,microwave photonics,optical variables measurement
更新于2025-11-28 14:24:03
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Active ring resonance cavity assisted single-mode all-optical microwave oscillator
摘要： A pure optical microwave oscillator with single mode oscillation is proposed and demonstrated. This system has no any electrical microwave devices as well as electro-optic (E/O) and opto-electronic (O/E) conversion. The oscillation frequency is chosen by Brillouin-selective sideband amplification, and the optical envelope detection and feedback modulation are implemented by a semiconductor optical amplifier (SOA). As a high-Q tunable optical comb filter, an active ring resonance cavity (ARRC) is employed to select one oscillation mode within the Brillouin gain region, and consequently a single mode oscillation signal can be generated. In the experiment, a single mode photonic microwave signal with frequency of 10.83 GHz and side-mode suppression ratio of 48 dB is obtained. The measured phase noise is ?88 dBc/Hz@10 kHz. In addition, the tunability is also demonstrated by adjusting the wavelength of the light source.
关键词： Microwave photonics,SBS,All-optical microwave oscillator
更新于2025-11-28 14:23:57
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100?GHz free spectral range-tunable multi-wavelength fiber laser using single–multi–single mode fiber interferometer
摘要： Six single–multi–single (SMS) mode fiber-based Mach–Zehnder Interferometers (MZI) with different spooling radii are demonstrated as spatial mode filtering elements for multi-wavelength laser generation. Free spectral range (FSR) tuning of the multi-wavelength output generated is realized by alternating between the six MZIs, which have different macro-bending losses. Additional FSR tuning is also realized by changing the spooling radius of the two-mode step index fiber section within the MZI setups from 80 mm to 30 mm, giving an FSR tuning range of 0.89–0.99 nm. All generated multi-wavelength outputs show high stability over a test period of 100 min. The proposed multi-wavelength lasers are highly suitable for various microwave photonics applications the field of such as microwave signal source generation and microwave photonic filtering.
关键词： free spectral range tuning,Mach–Zehnder Interferometer,microwave photonics,multi-wavelength fiber laser
更新于2025-11-28 14:23:57
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Microwave Photonic Signal Processing and Sensing Based on Optical Filtering
摘要： Microwave photonics, based on optical filtering techniques, are attractive for wideband signal processing and high-performance sensing applications, since it brings significant benefits to the fields by overcoming inherent limitations in electronic approaches and by providing immunity to electromagnetic interference. Recent developments in optical filtering based microwave photonics techniques are presented in this paper. We present single sideband modulation schemes to eliminate dispersion induced power fading in microwave optical links and to provide high-resolution spectral characterization functions, single passband microwave photonic filters to address the challenges of eliminating the spectral periodicity in microwave photonic signal processors, and review the approaches for high-performance sensing through implementing microwave photonics filters or optoelectronic oscillators to enhance measurement resolution.
关键词： Microwave photonics,photonic filtering,photonic signal processing,single sideband modulation,single passband microwave photonic filter,optical sensors
更新于2025-09-23 15:23:52
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Instantaneous microwave frequency measurement with high-resolution based on stimulated Brillouin scattering
摘要： A novel photonic method of instantaneous microwave frequency measurement (IMFM) based on Stimulated Brillouin scattering (SBS) is proposed. The principle of the technique is the employment of SBS effect to amplify/attenuate two adjacent frequency components, which result in a definite amplitude comparison function (ACF). Using this technique, the frequency of an unknown RF signal can be precisely obtained. Experimental results show the measurement capability of the proposed method over a frequency range of 0.47–23 GHz with a higher resolution of 8 MHz.
关键词： Amplitude comparison functions,Microwave photonics,Instantaneous microwave frequency measurement,Stimulated Brillouin scattering
更新于2025-09-23 15:23:52
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Real-time adaptive optical self-interference cancellation system for in-band full-duplex transmission
摘要： A real-time adaptive optical self-interference cancellation (RTA-OSIC) system is proposed and demonstrated for in-band full-duplex transmission. The RTA-OSIC system is controlled automatically by adaptive algorithm running on a real-time microcontroller STM32. Modified Hooke-Jeeves (MHJ) algorithm is proposed to search the optimal optical parameters more rapidly. Experimental results show that the MHJ algorithm requires 15-25 samples to find the optimal point. The RTA-OSIC system achieves more than 22 dB cancellation depth within 0-700MHz frequency band. Compared with the existing adaptive OSIC system which uses the Nelder–Mead Simplex algorithm, there are 60% less samples for our RTA-OSIC system with MHJ algorithm.
关键词： self-interference cancellation,Modified Hooke-Jeeves (MHJ) algorithm,microwave photonics,real-time adaptation
更新于2025-09-23 15:23:52
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Performances of Microwave Photonic Notch Filter Based on Microring Resonator with Dual-drive Modulator
摘要： A tunable microwave photonic notch ?lter with ultrahigh radio frequency (RF) rejection ratio is achieved by using a dual-drive Mach–Zender modulator and a microring resonator. In addition, we dedicated to clarify the mechanisms of the microwave photonic notch ?lters based on a microring resonator under both overcoupled and undercoupled states and the performance differences between these two situations are investigated in detail. Furthermore, the experimental results show that the cancellation microwave photonic notch ?lter with ultrahigh RF rejection ratio can be achieved with both undercoupled and overcoupled microring resonators. Besides, an RF rejection ratio exceeding 50 dB was achieved for a microring resonator with an optical extinction ratio of only 4 dB, where a 46-dB enhancement from optical to RF response is obtained. Also, the bandwidth of the microwave photonic ?lter can tuned from 0.65 to 2.2 GHz by adjusting the coupling ratio of the ring resonator. Meanwhile, by tuning the wavelength of the optical carrier, the ?ltering frequency can be tuned and a tuning range of about 25 GHz was achieved. The implementation is much simpler and more economical compared with previous reports and has great potential in monolithic integration of microwave photonic ?lters on chip.
关键词： Optical ?lter,Microwave photonics,Microring resonator,Integrated optics devices
更新于2025-09-23 15:23:52
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Ripple Suppression in Broadband Microwave Photonic Phase Shifter Frequency Response
摘要： This paper presents a detailed investigation on the cause of ripples in the frequency response of a microwave photonic phase shifter implemented using a 90° hybrid coupler. It was found that an unwanted radio frequency (RF) modulation sideband is generated at the modulator output due to the 90° hybrid coupler amplitude and phase imbalance. This resulted in phase shifter output RF signal amplitude variation and phase deviation. Experimental results demonstrated that incorporating an optical filter in the phase shifter structure can reduce the amplitude variation and phase deviation from 4.2 dB to 2.2 dB and from ±12° to ±3.8°, respectively, over a wide frequency range. A comparison of the loss and the dynamic range of the microwave photonic phase shifter implemented using a 90° hybrid coupler with a conventional fiber optic link is also presented.
关键词： phase shifters,microwave photonics,optical signal processing
更新于2025-09-23 15:23:52
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[IEEE 2018 20th International Conference on Transparent Optical Networks (ICTON) - Bucharest (2018.7.1-2018.7.5)] 2018 20th International Conference on Transparent Optical Networks (ICTON) - Generation of mmWave 5G Signals Using Microwave Photonics
摘要： Bandwidth constraints is, nowadays, a mayor problem in the implementation of next generation 5G networks. In order to cope with increasing bandwidth demands, the use of the millimeter-wave (mmWave) spectrum, together with Radio over Fiber (RoF) technology has been proposed. In this work, we will present our recent advances in the generation of mmWave signals for 5G using Microwave Photonics.
关键词： microwave photonics,mobile optical communications,radio over fiber
更新于2025-09-23 15:22:29
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Microwave photonics‐based all optical wavelength conversion of Nyquist‐DP‐16QAM for flex‐grid optical networks with 112 Gbps
摘要： We propose and demonstrate an all optical wavelength conversion of Nyquist differential phase 16 quadrature amplitude modulation based on microwave photonics signal processing for flex-grid optical networks. By analyzing the mechanism of the microwave photonics and the components, multi-adjusting the parameters of wavelength tunable laser with smooth and adjustable optical intensity can be obtained. Then, the multi-channel photonic signals with the minimal guard space of 5 GHz can be obtained, which provide more than 20 flex-grids for optical transmission with transparent rate and format. The optical power of converted wavelengths, optical signal-to-noise ratio, error vector magnitude, and bit error rate (BER) are studied under the condition of different flex-grids, the frequencies of which are from 15 GHz to 36 GHz. The channel frequency spacing and amplitude of the converted wavelength can be dynamically adjusted via parameter configuration. Flex-grid spacing strategies and channel selecting strategies are given. The BER performance of all converted channels can fall below the forward error correction threshold of 3.8 × 10?3 by optimizing the optical power of the receiver end. The results show the tradeoff between the BER and the detected optical power of the receiver end. These research findings could provide solutions for spectrum allocation and routing selection when wavelength conversion is needed in optical links.
关键词： coherent communication,microwave photonics,wavelength conversion,flex-grid optical networks
更新于2025-09-23 15:22:29