Microwave Photonic Generation Of Local Oscillator Signal And Optical Frequency Comb

Along with the rapid development of technology such as satellite communications,broadband radio and radar,the requirements for system bandwidth and frequency have become higher,and traditional electronic systems cannot meet these needs.Microwave photonics is an emerging discipline that combines microwave technology and photonic technology.It solves the problems in traditional electronic technology.It has small size,light weight,small transmission loss,wide allowable frequency bandwidth,large capacity,and anti-electromagnetic interference.This paper mainly studies the generation of local oscillator signal and optical frequency comb based on microwave photons.The following tasks have been completed: 1.This paper introduces the typical link of microwave photonics,and analyzes the advantages of microwave photonics compared to traditional electronic technology.Some application scenarios of microwave photonics are described.Then,this paper summarizes the research status and several common generation techniques of local oscillator signal generation and optical frequency comb generation in domestic and overseas.Some core components in microwave photonics are introduced,and the performance indicators of local oscillator signals and optical frequency combs are described.2.This paper studies a tunable frequency sextupled scheme based on Dual-parallel Mach-Zehnder Modulator(DPMZM).This scheme uses only one modulator and has a simple structure.In the simulation,the optical carrier and other spurious signals can be effectively suppressed,and a pure sextupling frequency local oscillator signal can be obtained after passing through the photodetector(PD).And by setting different RF signal frequencies,the tunability of the scheme is verified.3.This paper studies a frequency octupled scheme based on cascading two DP-BPSK.This scheme uses two cascaded DP-BPSKs,and each DP-BPSK achieves optical carrier suppressed double sideband(OCS-DSB).It can be seen that the optical carrier and other spurious signals are effectively suppressed in the simulation.This scheme does not use any filters and has a high frequency multiplication factor.The tunability of the scheme is also verified in simulation.4.This paper studies a local oscillator signal generation scheme based on the cascade of DP-BPSK and-DP-QPSK.The DP-BPSK is used to achieve OCS-DSB.The up-channel of DP-QPSK is used to obtain the sixth-order optical sideband required for the 12-tupling local oscillator signal.The down-channel of DP-QPSK is used to obtain the fourth-order optical sideband required for the octupling local oscillator signal.By adjusting the angle between the main axis of the polarizer(Pol)and the polarization beam combiner(PBC),the sixth-order or fourth-order optical signals are selected into the PD,and then the local oscillator signals with different frequency multiplication factors are obtained after photoelectric detection.This scheme has a high frequency multiplication factor,and different frequency multiplication factors can be selected to meet the needs of practical applications.5.This paper introduces the scheme of generating optical frequency combs based on cascaded DPMZM and cascaded Intensity Modulator(IM).The two schemes are simulated and verified using VPI,and the advantages and disadvantages of the two schemes are summarized.On this basis,a large number of optical frequency combs are generated based on cascading three IMs.Through simulation software and experiment,a 75-line optical frequency comb with tunable frequency spacing is obtained.