- 标题
- 摘要
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- 实验方案
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A microwave photonic phase-tunable mixer with local oscillator frequency doubling
摘要： A microwave photonic phase-tunable mixer with a doubled local oscillator (LO) frequency is presented based on an integrated dual-polarization dual-parallel Mach-Zehnder modulator (DP-DPMZM). A radio frequency (RF) signal is sent to one of the sub-DPMZMs via an electrical 90° hybrid coupler, and the carrier-suppressed single-sideband (CS-SSB) modulation is output. Another sub-DPMZM is modulated by a LO signal, and the 2nd-order carrier-suppressed double-sideband (CS-DSB) modulation is produced by combining a fiber Bragg grating (FBG). A single bias voltage of the modulator can change the phase shift linearly. The mixing signal with double LO frequency and phase shift can be acquired after the photodetector. Experimental setup is implemented, and the results indicate that the spur suppression ratios of the up/down-converted signals are 22.5 dB and 25.2 dB. The spurious-free dynamic range (SFDR) values are 102.97 dB·Hz2/3 in the down-conversion mode and 100.81 dB·Hz2/3 in the up-conversion mode. The phase shift can be varied continuously in the range of 360°. The proposed compact link is characterized by function multiplexing, half reduction of the LO frequency and high electrical purity.
关键词： Mixer,Microwave photonics,Phase shifter,Frequency doubling
更新于2025-09-23 15:22:29
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Microwave Photonic Devices Based on Liquid Crystal on Silicon Technology
摘要： This paper reviews the recent developments in microwave photonic devices based on liquid crystal on silicon (LCOS) technology. The operation principle, functions and important specifications of an LCOS based optical processor are described. Three microwave photonic devices, which are microwave photonic notch filters, phase shifters and couplers, reported in the past five years are focused on in this paper. In addition, a new multi-function signal processing structure based on amplitude and phase control functions in conjunction with a power splitting function in a commercial LCOS based optical processor is presented. It has the ability to realize multiple time-shifting operations and multiple frequency-independent phase shifting operations at the same time and control multiple RF signal amplitudes, in a single unit. The results for the new multi-function microwave photonic signal processor demonstrate multiple tunable true time delay and phase shifting operations with less than 3 dB amplitude variation over a very wide frequency range of 10 to 40 GHz.
关键词： phase shifters,optical signal processing,filters,true time delays,microwave photonics
更新于2025-09-23 15:22:29
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Angle-of-Arrival Measurement System Using Double RF Modulation Technique
摘要： A new technique for determining the angle of arrival (AoA) of an RF signal is presented. It is based on a cascaded modulator structure, where continuous wave light from an optical source is modulated by an incoming RF signal twice. The AoA of an RF signal can be determined by the system output RF signal power. The proposed structure is capable for measuring the AoA of both narrow and broadband RF signals. This overcomes the limitation in all previously reported photonics-based AoA measurement systems, which are applicable to either a single-frequency RF signal or a broadband RF signal. It also does not involve electrical components and high extinction ratio modulators, which are required in reported structures. Experimental results are presented that show an AoA measurement range of 0° to over 65° with errors of less than 1.9° for a microwave signal at 2.65 and 12.62 GHz. Results also show that the system is capable to measure the AoA of a pseudorandom binary sequence signal at a microwave frequency.
关键词： notch filters,Direction-of-arrival estimation,phased arrays,microwave photonics
更新于2025-09-23 15:22:29
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Distributed Measurement of Polarization Mode Coupling in Polarization Maintaining Fibers Using Microwave Photonic Filter Technique
摘要： Polarization mode coupling (PMC) is a detrimental effect that limits the polarization maintaining performance of polarization maintaining fibers (PMF). In this paper, we propose and demonstrate a novel method based on a principle similar to that of a microwave photonic filter (MPF) for the PMC distribution measurement. By regarding the PMF with PMC taking place as an MPF and measuring its transfer function in frequency domain, we are able to identify the intensities and locations of PMC events along PMFs. After detailed theoretical analysis and numerical simulations, validation experiments have been conducted on four PMF segments with rotational splicing between each other to manually generate PMCs. The measurement results of PMC positions and strengths are in accordance with the preset values. With a frequency scanning step of 16 MHz and a range of 14.4 GHz, such method can achieve a spatial resolution of 30 m and a measurement range of 27 km. The proposed method is suitable for the measurement of PMCs along PMFs up to tens of kilometers.
关键词： microwave filters,optical fibers,microwave photonics,Optical fiber polarization
更新于2025-09-23 15:21:21
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[IEEE 2019 International Topical Meeting on Microwave Photonics (MWP) - Ottawa, ON, Canada (2019.10.7-2019.10.10)] 2019 International Topical Meeting on Microwave Photonics (MWP) - Heterogeneous multicore fiber for optical beamforming
摘要： We experimentally demonstrate, for the first-time to our knowledge, optical beamforming for microwave phased array antennas implemented with a heterogeneous multicore fiber link. The multicore fiber has been engineered to act as an optical sampled true time delay that allows to implement radiofrequency signal processing in a distributed way. It comprises 7 trench-assisted cores where each core is fabricated with different dimensions and core dopant concentration, as to feature a different group delay and chromatic dispersion behavior. We emulated different radio beamsteering scenarios where the beam-pointing angle is modified by tuning the optical wavelength in a 20-nm range, while squint-beam effects are avoided.
关键词： Microwave Photonics,optical beamforming networks,multicore fibers
更新于2025-09-23 15:21:01
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[IEEE 2019 International Workshop on Fiber Optics in Access Networks (FOAN) - Sarajevo, Bosnia and Herzegovina (2019.9.2-2019.9.4)] 2019 International Workshop on Fiber Optics in Access Networks (FOAN) - An Affordable Laboratory Photodiode up to 11.5 GHz for Microwave Photonics Experiments
摘要： Low-cost optoelectronic devices are the main limiting factor when it comes to scaling the current access networks based on microwave photonics to the capabilities of smart cities. The use of affordable photodiodes could decrease the use of microwave photonics, since it is part of each system. In this paper we evaluate the frequency response of a coaxial packaged photodiode. The design of an electric circuit is presented. The results from the vector network analyzer show that the coaxial packaged photodiode makes photodetectors applicable up to 11.5 GHz. In addition, an experimental verification of the photodiode in an optoelectronic oscillator is performed.
关键词： photodetector,optoelectronic oscillator,photodiode,microwave photonics
更新于2025-09-23 15:21:01
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Broadband Cognitive Radio Enabled by Photonics
摘要： Cognitive radio is considered as a possible disruptive force to improve the spectral resource efficiency through sensing and interacting with the environment. Traditional electrical technologies to implement the cognitive radio face challenges in terms of bandwidth, resolution, and speed. In this paper, the concept and architecture of broadband cognitive radio systems enabled by photonics are proposed. Key microwave photonic techniques for the architecture are reviewed, including the photonics-based spectrum sensing, the photonic arbitrary waveform generation, the photonics-based self-interference cancellation processing, and the microwave photonic dechirp processing and radar imaging. A preliminary demonstration of a cognitive radar system enabled by photonics is performed. The future possible research directions on this topic are discussed.
关键词： Cognitive radio,spectrum sensing,microwave photonics,radar imaging,self-interference cancellation,waveform generation
更新于2025-09-23 15:21:01
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Sampled-Data Adaptive ESO Based Composite Control for Nano-Positioning Systems
摘要： In this paper, we demonstrate ultra-fast millimeter wave beam steering with settling times below 50 ps. A phased array antenna with two elements is employed to realize beam steering. The phased array feeder is implemented with a recently introduced time delay line that provides, at the same time, an ultra-fast tunability, broadband operation, and continuous tuning. Our implementation is used to perform symbol-by-symbol steering. In our demonstration, the beam direction is switched between two sequentially transmitted symbols toward two receivers placed 30° apart. We show the successful symbol-by-symbol steering for data streams as fast as 10 GBd. The suggested scheme shows that the ultra-fast beam steering is becoming practical and might ultimately enable novel high bit-rate multiple access schemes.
关键词： microwave photonics,millimeter wave communication,Ultra-fast beam steering,radio access network
更新于2025-09-23 15:19:57
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[IEEE 2019 20th International Conference on Solid-State Sensors, Actuators and Microsystems & Eurosensors XXXIII (TRANSDUCERS & EUROSENSORS XXXIII) - Berlin, Germany (2019.6.23-2019.6.27)] 2019 20th International Conference on Solid-State Sensors, Actuators and Microsystems & Eurosensors XXXIII (TRANSDUCERS & EUROSENSORS XXXIII) - Infrared Photodetector with Copper Resonator in Silicon Nanohole Array
摘要： A highly linear broadband photonic-assisted analog-to-digital converter (ADC) based on high-frequency optical sampling utilizing a dual output Mach–Zehnder modulator operating with signal frequencies up to 50 GHz is presented. The pulses employed in the optical sampling were generated by a cavity-less pulse source operated at 10 GHz in preference to conventional mode-locked lasers. The optical sampling front-end greatly extends the operational frequency range of the Nyquist limited electronic digitization back-end. The performance of the sampling system is characterized with 7.1 effective number of bits (ENOBs) at 40 with 5 GHz fully accessible bandwidth, and greater than 99 dB·Hz2/3 spurious free dynamic range for the 30–40 GHz frequency range. Furthermore, more than 8 ENOB was achieved by reducing the effective bandwidth to 1 GHz with a digital ?lter, demonstrating the additional advantage of using a higher sampling rate compared to previous demonstrations. A new ?gure of merit of photonic-assisted sub-sampled ADCs is also presented accompanied with a comparison to previous implementations.
关键词： microwave photonics,optical data processing,sampling,Analog-digital conversion,detection,sub-sampling,optical ?ber communications
更新于2025-09-23 15:19:57
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[IEEE 2018 Asia Communications and Photonics Conference (ACP) - Hangzhou, China (2018.10.26-2018.10.29)] 2018 Asia Communications and Photonics Conference (ACP) - Photonic generation of microwave frequency shift keying signals based on dual parallel Mach-Zehnder modulator structure
摘要： A novel scheme to generate microwave frequency shift keying (FSK) signals is proposed and verified by a simulation. The main devices are two single-drive Mach Zehnder modulators (MZM) and a commercial phase modulator (PM). They are parallelly settled to perform the FSK signal generation. In this simulation work, two MZMs are driven by the RF signals with a phase difference which is introduced by an electrical phase shifter (EPS). Simultaneously, the PM is driven by a binary coding signal. The simulation results show that when the two MZMs are biased at the maximum transmission point (MATP), a microwave FSK signal can be obtained with the frequency is two times as large as the RF frequency for bit '0' and four times as large as the RF frequency for bit '1', respectively. It should be noted that the system shows excellent adaption to the non-ideal extinction radio and the inherent inaccurate phase shift of the electrical phase shifter. Therefore, the generated microwave FSK signal can meet the requirement of high-frequency applications.
关键词： high-frequency applications,microwave signal generation,microwave photonics,frequency shift keying
更新于2025-09-19 17:15:36