39 results about "Microwave photonics" patented technology

The present invention discloses a tunable single pass band microwave photonics Hilbert transform filter system that is based on broad spectrum light source polarization processing and combines with spectral notch phase shift and dispersion integral effect. The system comprises an amplification spontaneous emission broad spectrum light source, an optical fiber Bragg grating, a first polarization polarizer, a first polarization controller, a polarization beam splitter, an adjustable light delay line, an adjustable light attenuator, a phase shift optical fiber grating, a polarization beam combiner, a second polarization controller, a polarization modulator, a third polarization controller, a second polarization polarizer, a dispersion compensation module, and a high-speed photoelectric detector that are all connected with the amplification spontaneous emission broad spectrum light source. According to the system, random tuning of the spectrum position of the bandpass Hilbert transform is realized through turned light delay in a broad spectrum microwave band, so that the Hilbert transform of the bandpass microwave signal is realized. In addition, the system output has no base frequency response and no periodic spectral response, and ensures the singleness and immunity of channel selection.

The invention belongs to the field of microwave photonics, and discloses a system and method for frequency tunable microwave phase shifting. The method comprises the following steps that after a continuous light carrier is splitted, one beam of the continuous light carrier is processed by a MZ Mach-zehnder, and double-sideband optical signals restrained by the carrier are produced; the other beam of the continuous light carrier is processed by a phase modulator, and phase-shifted light carrier signals are produced; two beams of light signals are combined in a wave mode, one one-step sideband is removed through a tunable micro-ring filter in a filtering mode, a frequency-moved carrier signal and a phase-shifted carrier signal are obtained, photovoltaic conversion is carried out through a photoelectric detector, and a phase shift microwave electrical signal is produced; the resonant frequency of the tunable micro-ring filter is equal to any one-step sideband of the two one-step sidebands output by the MZ Mach-zehnder by changing the frequency of an input voltage drive signal and the resonant wavelength of the tunable micro-ring filter, and the frequency of the phase shift microwave signal is changed. The system and method for the frequency tunable microwave phase shifting is stable in output performance, fast in phase shift adjusting response, small in output microwave range fluctuation and continuously adjustable in wide frequency range.

A microwave photonics-based wide-range high-precision microwave frequency measurement method and device, belonging to the technical field of microwave photonics. Tunable laser, coupler, phase modulator, intensity modulator 1, intensity modulator 2, filter, vector network analyzer, isolator, single-mode fiber 1, single-mode fiber 2, circulator 1, circulator 2 , Microwave signal source 1, microwave signal source 2, DC regulated power supply 1, DC regulated power supply 2, photoelectric converter. The amplitude-frequency characteristic curve and phase-frequency characteristic curve are measured by the vector network analyzer, so as to realize the rough measurement and precise measurement of the unknown signal frequency. The present invention uses two pump lights to realize the offset of the gain spectrum and the loss spectrum, and increase the multi-frequency measurement range; the present invention constructs a phase-shift-frequency function curve based on the Brillouin scattering phase-frequency characteristic, and obtains the measured phase-shift-frequency function curve through the phase-shift-frequency function curve The frequency value of the microwave signal improves the measurement accuracy.

The invention discloses a device for generating multi-wavelength laser larger than two times of a Brillouin frequency shift interval. The device comprises an adjustable laser source, a first optical fiber coupler, a first optical amplifier, a first optical circulator, a Brillouin gain fiber, an N-2-order Brillouin frequency shifter, a second optical circulator, an adjustable band pass filter and a second optical fiber coupler, wherein N is a natural number larger than 2. Multi-wavelength Brillouin-Stock signal light of N times of the interval is acquired through cyclic cascade frequency shift of Brillouin pump light in the Brillouin gain fiber and the N-2-order Brillouin frequency shifter. The invention further discloses a method for generating multi-wavelength laser larger than two times of the Brillouin frequency shift interval. A multi-wavelength Brillouin laser device with wavelength interval larger than two times of the Brillouin frequency shift interval is realized through a full-optical-fiber structure for the first time, and the multi-wavelength Brillouin laser device is especially suitable for the technical field of optical communication, optical sensing and microwave photonics.

The invention discloses an optical device measurement method based on double sideband modulation, and belongs to the technical fields of optical device measurement and microwave photonics. First, the radio frequency signal is modulated on the first optical carrier signal by using the optical double sideband modulation method to generate a double sideband modulation signal; then the double sideband modulation signal is combined with the second optical carrier signal after passing through the optical device to be tested, and the second There is a frequency difference between the optical carrier signal and the first optical carrier signal; use a photodetector to beat the combined signal, and then extract the amplitude of the +1-order sideband signal and the -1-order sideband signal in the beat frequency signal Information; scanning the frequency of the radio frequency signal, that is, obtaining the wideband amplitude-frequency response of the optical device to be tested. The invention also discloses an optical device measurement device based on double sideband modulation. The invention greatly improves the measurement range and measurement efficiency while reducing the complexity and cost of the system, and more importantly, opens up a new direction for the optical device measurement technology.