In recent years,thin-film lithium niobate(TFLN)electro-optic(EO)modulators have developed rapidly and are the core solution for the next generation of microwave photonics(MWP)problems.We designed and fabricated a dual...In recent years,thin-film lithium niobate(TFLN)electro-optic(EO)modulators have developed rapidly and are the core solution for the next generation of microwave photonics(MWP)problems.We designed and fabricated a dual-parallel Mach-Zehnder modulator(DPMZM)based on TFLN,achieving a 3 dB electro-electro(EE)bandwidth of 29 GHz and a low drive voltage(Vπ=6 V).The device we manufactured is metal-encapsulated.It is noteworthy that we proposed a single-channel Doppler frequency shift(DFS)measurement system based on this device and conducted verification experiments.We coupled light from an external laser into the chip and passed it through each of the two sub-MZMs of the DPMZM.These lights were modulated by echo signals and reference signals.By measuring the frequency of the output signal,we can obtain a DFS value without directional ambiguity.The success of this experiment marks a key step in the practical application of TFLN modulators in MWP.展开更多
Based on free space laser communication, this article describes the working principle of electro-optical frequency shifting, designs an optical adaptive filtering module, and builds the core module of the dynamic opti...Based on free space laser communication, this article describes the working principle of electro-optical frequency shifting, designs an optical adaptive filtering module, and builds the core module of the dynamic optical Doppler shifting simulator for laser channel. It is expected to be applied to the heaven-ground integrated communication link. In this article, we adopt the electro-optical frequency shifting technique combined with the microwave-light wave. In the 1 550 nm band, the negative feedback algorithm is used to complete the adaptive filtering, which realizes optical Doppler frequency shifting and high-precision locking. The frequency shift range reaches +5.5-+32 GHz, and the analog precision is better than 645 Hz. When the microwave frequency is greater than 13.5 GHz, the signal-to-noise ratio(SNR) of the output optical power reaches 20 d B, which lays the foundation for the next stage space laser communication.展开更多
We demonstrate a package-level passive equalization technology in which the wire-bonding-induced resonance effect is used to compensate for the limited gain strength within the Nyquist frequency.The corresponding gain...We demonstrate a package-level passive equalization technology in which the wire-bonding-induced resonance effect is used to compensate for the limited gain strength within the Nyquist frequency.The corresponding gain strength under various inductance and capacitance combinations could be quantitatively determined using a numerical simulation.With the increase in the Nyquist frequency,the capacitance shows a greater effect on the gain strength than the inductance.Therefore,the parasitic capacitance should be decreased to realize the desired gain strength at a higher Nyquist frequency.With this equalization technology,gain strength of 5.8 dB is obtained at 22 GHz,which can compensate for the limited bandwidth for the 112 Gbps pulse amplitude modulation(PAM4)signal.The experimental results show that 112 Gbps/λ PAM4 transmission based on a directly modulated laser(DML)module can be realized with a bit error rate of 1×10^-3 at a received optical power of 3d Bm.展开更多
Microwave photonics(MWP)studies the interaction between microwaves and light waves,including the generation,transmission,and processing of microwave signals.Integrated MWP using photonic integrated circuits(PICs)can a...Microwave photonics(MWP)studies the interaction between microwaves and light waves,including the generation,transmission,and processing of microwave signals.Integrated MWP using photonic integrated circuits(PICs)can achieve compact,reliable,and green implementation.However,most PICs have recently been developed that only contain one or a few devices.Here,we propose a multi-channel PIC that covers almost all devices in MWP.Our PIC integrates lasers,modulators,amplifiers,and detectors in the module,successfully manufacturing an eight-channel array transceiver module.We conducted performance tests on the encapsulated transceiver module and found that the cascaded bandwidth of the eightchannel transceiver module was greater than 40 GHz,and the spurious-free dynamic range(SFDR)of the broadband array receiver module was greater than 94 dBm·Hz2/3.The noise figure(NF)is less than-35 dB and the link gain is greater than-26 dB.The success of multi-channel PIC marks a crucial step forward in the implementation of large-scale MWP.展开更多
基金supported by the National Natural Science Foundation of China(No.61727815)and the National Key Research and Development Program of China(No.2022YFB2803200).
文摘In recent years,thin-film lithium niobate(TFLN)electro-optic(EO)modulators have developed rapidly and are the core solution for the next generation of microwave photonics(MWP)problems.We designed and fabricated a dual-parallel Mach-Zehnder modulator(DPMZM)based on TFLN,achieving a 3 dB electro-electro(EE)bandwidth of 29 GHz and a low drive voltage(Vπ=6 V).The device we manufactured is metal-encapsulated.It is noteworthy that we proposed a single-channel Doppler frequency shift(DFS)measurement system based on this device and conducted verification experiments.We coupled light from an external laser into the chip and passed it through each of the two sub-MZMs of the DPMZM.These lights were modulated by echo signals and reference signals.By measuring the frequency of the output signal,we can obtain a DFS value without directional ambiguity.The success of this experiment marks a key step in the practical application of TFLN modulators in MWP.
基金supported by the National Natural Science Foundation of China(No.61727815)the Opened Fund of the State Key Laboratory of Integrated Optoelectronics(No.IOSKL2018KF18)
文摘Based on free space laser communication, this article describes the working principle of electro-optical frequency shifting, designs an optical adaptive filtering module, and builds the core module of the dynamic optical Doppler shifting simulator for laser channel. It is expected to be applied to the heaven-ground integrated communication link. In this article, we adopt the electro-optical frequency shifting technique combined with the microwave-light wave. In the 1 550 nm band, the negative feedback algorithm is used to complete the adaptive filtering, which realizes optical Doppler frequency shifting and high-precision locking. The frequency shift range reaches +5.5-+32 GHz, and the analog precision is better than 645 Hz. When the microwave frequency is greater than 13.5 GHz, the signal-to-noise ratio(SNR) of the output optical power reaches 20 d B, which lays the foundation for the next stage space laser communication.
基金supported by the National Natural Science Foundation of China(NSFC)(Nos.61625504,61527820,61635001,and 11674313)
文摘We demonstrate a package-level passive equalization technology in which the wire-bonding-induced resonance effect is used to compensate for the limited gain strength within the Nyquist frequency.The corresponding gain strength under various inductance and capacitance combinations could be quantitatively determined using a numerical simulation.With the increase in the Nyquist frequency,the capacitance shows a greater effect on the gain strength than the inductance.Therefore,the parasitic capacitance should be decreased to realize the desired gain strength at a higher Nyquist frequency.With this equalization technology,gain strength of 5.8 dB is obtained at 22 GHz,which can compensate for the limited bandwidth for the 112 Gbps pulse amplitude modulation(PAM4)signal.The experimental results show that 112 Gbps/λ PAM4 transmission based on a directly modulated laser(DML)module can be realized with a bit error rate of 1×10^-3 at a received optical power of 3d Bm.
基金supported by the National Natural Science Foundation of China(No.62035009).
文摘Microwave photonics(MWP)studies the interaction between microwaves and light waves,including the generation,transmission,and processing of microwave signals.Integrated MWP using photonic integrated circuits(PICs)can achieve compact,reliable,and green implementation.However,most PICs have recently been developed that only contain one or a few devices.Here,we propose a multi-channel PIC that covers almost all devices in MWP.Our PIC integrates lasers,modulators,amplifiers,and detectors in the module,successfully manufacturing an eight-channel array transceiver module.We conducted performance tests on the encapsulated transceiver module and found that the cascaded bandwidth of the eightchannel transceiver module was greater than 40 GHz,and the spurious-free dynamic range(SFDR)of the broadband array receiver module was greater than 94 dBm·Hz2/3.The noise figure(NF)is less than-35 dB and the link gain is greater than-26 dB.The success of multi-channel PIC marks a crucial step forward in the implementation of large-scale MWP.
