158results about How to "High modulation rate" patented technology

The making process of lithium niobate modulator includes making substrate with lithium niobate crystal with proper crystal cutting direction and electric field utilizing direction; making light waveguide on the lithium niobate crystal; making modulating electrodes including central signal electrode and earth electrode and to form push-pull structure with the light waveguide; making microstrip matching structure in the input and output of the modulating electrodes; and setting buffering layer structure between the modulating electrode and light waveguide. Owing to the smart design of the modulating electrodes, the light waveguide and the matching structure in between, the lithium niobate modulator has high modulating rate, low insertion loss, high extinction ratio, low hemi-wave voltage, less electric reflection, and high reliability.

The invention provides a graphene field effect transistor terahertz wave modulator and a manufacture method thereof and aims to increase the modulating speed and depth of the graphene field effect transistor terahertz wave modulator. The graphene field effect transistor terahertz wave modulator comprises a semiconductor substrate, and a medium layer, a graphene film and source and drain electrodes which are arranged on the substrate, and an annular grating electrode which is arranged on the back of the substrate. The terahertz wave modulator is characterized in that the medium layer is an Al2O3 layer, and the thickness ranges from 5 to 100nm; the Al2O3 is deposited by the ALD (atomic layer deposition) method, and the Al2O3 is high in evenness, is free of defects and pores and has better voltage resistance; the leakage current is reduced greatly. The modulating speed of the terahertz wave modulator can be 178 KHz, the corresponded modulating depth is larger than 22%, and the modulating speed and depth are increased significantly; the terahertz wave modulator can be widely applied to the fields of terahertz wave communication systems, terahertz wave detection and terahertz wave imaging.

The invention discloses a micro-ring resonant cavity electro-optical modulator based on a graphene/molybdenum disulfide heterojunction. The micro-ring resonant cavity electro-optical modulator comprises a substrate layer, a direct-light waveguide, a micro-ring resonant cavity waveguide and a graphene covering layer. The direct-light waveguide and the micro-ring resonant cavity waveguide are embedded into the substrate layer, and a coupling space is reserved between the direct-light waveguide and the micro-ring resonant cavity waveguide. The upper surface of the micro-ring resonant cavity waveguide is covered with a part of the graphene covering layer. The graphene covering layer comprises a first graphene layer, a second graphene layer, molybdenum disulfide, a first electrode and a second electrode, wherein the first graphene layer and the second graphene layer are isolated by the molybdenum disulfide, the first graphene layer stretches outwards from one side of the micro-ring resonant cavity waveguide and is connected with the first electrode, and the second graphene layer stretches outwards from the other side of the micro-ring resonant cavity waveguide and is connected with the second electrode. The micro-ring resonant cavity electro-optical modulator has extremely low optical loss, a low thermo-optical coefficient, low insertion loss, large environment temperature tolerance, a good modulation depth and a high extinction ratio.

The invention provides a frequency shift keying (FSK) optical modulation signal generator based on a silicon-based micro ring resonator, comprising an adjustable laser, a radio frequency signal generator, a Mach-Zehnder modulator, a data source and a silicon-based micro ring resonator system, wherein the adjustable laser is connected with the input end of the Mach-Zehnder modulator to transmit optical carrier signals, the radio frequency signal generator is connected with the radio frequency interface of the Mach-Zehnder modulator to transmit high frequency electric signals, the output end of the Mach-Zehnder modulator is connected with the silicon-based micro ring resonator system to transmit carrier suppression optical signals, and the data source is connected with the silicon-based micro ring resonator system to transmit electric signals with adjustable amplitude. The silicon-based micro ring resonator used in the invention has simple structure and small volume, easy integration, simple modulation, convenient control and high modulation velocity which is up to a plurality of Gbit/s, and the radius of the micro ring is only a plurality of microns to dozens of microns.

The invention discloses a planar waveguide type near-and-mid infrared light modulator based on graphene-chalcogenide glass, and belongs to the technical field of electro-optical modulators. The optical modulator solves the problems in modulation and demodulation of integrated photonic devices based on optical signals of near-and-mid infrared light ranging from 1.55 microns to 3 microns. The modulator comprises a substrate layer, ridge-shaped light waveguide layers, a first strut and a second strut, wherein the ridge-shaped light waveguide layers, the first strut and the second strut are arranged on the substrate layer; a first graphene layer and a second graphene layer are arranged on the ridge-shaped light waveguide layers; the first graphene layer extends to the upper surface of the first strut, and the second graphene layer extends to the upper surface of the second strut; isolation medium layers are arranged between the ridge-shaped optical waveguide layer and the first graphene layer, between the ridge-shaped optical waveguide layer and the second graphene layer, between the first graphene layer and the second graphene layer, between the first graphene layer and the first strut, and between the second graphene layer and the second strut respectively; a first electrode is arranged on the first graphene layer on the first strut, and a second electrode is arranged on the second graphene layer on the second strut. The modulator is used for signal modulation and demodulation in the integrated photonic devices.

The invention discloses an all-optical modulator apparatus based on black phosphorus. The apparatus includes a pumped laser source, a direct current continuous laser source, a reflector, a dichroic laser beam combiner, a convex lens, a micro nano optical fiber, the black phosphorus, and a bandpass optical filter. The black phosphorus of the invention has good saturated absorption characteristic of spectra from visible light to near infrared light, and can work in a broadband spectrum range. The all-optical modulator apparatus based on the black phosphorus employs the all-optical modulation, overcomes the problem of modulation speed bottleneck of the electro-optical modulation, and has the advantages of the fast optical modulation speed, the low power consumption, the high modulation depth, and compatibility with an optical fiber system.

The invention belongs to the field of quantum private communication and specifically relates to a single photon source based on a Faraday-Sagnac loop and a realization method thereof. The single photon source is characterized in that a system of the single photon source includes a laser device, a circulator, a polarization analyzer and the Faraday-Sagnac loop which includes a four-port optical-fiber beam splitter, a phase modulator and a Faraday rotating mirror. Continuous light output by the laser device enters the four-port optical-fiber beam splitter via the circulator. The four-port optical-fiber beam splitter divides the continuous light into two beams of orthogonal-linear polarized light, which are identical in amplitude and phase. The two beams of linear polarized light are transmitted in opposite directions along the Faraday-Sagnac loop and modulated by the phase modulator at different moments. The two beams of modulated linear polarized light are overlaid in the four-port optical-fiber beam splitter and then enter the polarization analyzer after being coupled by the circulator. The advantages of the single photon source based on the Faraday-Sagnac loop are that generated light pulses have a high extinction ratio and a narrow spectral width so that polarization dispersion of the light pulses which are transmitted in a long-distance optical fiber is reduced.

The method for monitoring a wireless link of a wireless node of a CPE device during operation of the CPE device, comprises the steps of taking samples of one or several of the following parameters in a defined time interval: Received Signal Strength (RSSI), modulation rate (Physical Layer Rate) and/or the number of spatial streams used for the wireless link, and calculating an average for that parameters by including a filtering of said parameters.

Disclosed a method for one time extension forming the semiconductor laser and mode spot switch comprises following steps: (1), on the N type indium phosphide substrate, extending growing the N type indium phosphide breaker, a lower waveguide layer, a 2.4 ª–m indium phosphide space layer, a lower light-limited layer of active region, a compression strain quanta active region, a upper light-limited layer, a P type indium phosphide envelope, and a high doping P type indium gallium arsenide ohmic electrode contract layer; (2), utilizing the wet corrosion process to etch the upper carinate shape of laser and mode spot switch; (3) utilizing the auto-alignment process to etch the lower carinate shape; (4), growing the SiO2 insulating layer and opening a electrode window; (5) decreasing the substrate of extended plate to 100 ª–m, and manufacturing P/N electrodes to be scribed into the tube core of 250í‡600ª–m.

The present invention relates to the field of optical module, and provides a high-speed optical module for an optical fiber channel. The optical module can be used for 16G optical fiber channel, and comprises parts for emitting, receiving, clock data recovery and controlling. The optical module can be downward compatible with the application of 8G optical fiber channel and 4G optical fiber channel, support the diagnostic tests on optical circuit loopback and electrical circuit loopback, and provide stable receiving alarming. The optical module of the present invention, when serving as the interface between optical fiber channel systems and the interface between optical storage network storage devices, has the characteristics of miniaturization and low power consumption, and can improve port application density; the module supports hot swapping, which facilities the field debugging of the system, and can realize the replacing of the optical module without power down; and the module supports a digital diagnostic interface, and the network administrator can monitor the working state of the optical module by using the communication interface.

The invention discloses a Schottky gate array type terahertz modulator and a regulation and control method thereof. A periodic gate type metal-semiconductor surface plasmon waveguide structure is adopted, the characteristics of Schottky contact formed by a metal-semiconductor interface and superposition of the Schottky contact and terahertz surface plasmon polariton position are utilized, a positive electrode and a negative electrode are led in and voltage is exerted, so that the terahertz modulation function of the Schottky gate array type terahertz modulator is achieved. The Schottky gate array type terahertz modulator combines a waveguide optical microstructure with a semiconductor electron device together, so that the Schottky gate array type terahertz modulator is well integrated with other electronic components and systems, and the optical functions of terahertz wave transmission and resonance oscillation are achieved. The Schottky gate array type terahertz modulator works from 2.2THz to 3.2THz, the working frequency can be tuned along with the working voltage, the maximum modulation depth is 16dB, and the highest modulation rate is 22MHz. The Schottky gate array type terahertz modulator is an on-chip electronically-controlled high-speed terahertz modulator which is in a small type and can be integrated, and the application requirements for terahertz broadband wireless communications are met.

The invention discloses a graphene absorption-type electro-optic modulator based on a D-type superfine optical fiber. The graphene absorption-type electro-optic modulator based on the D-type superfine optical fiber comprises a base layer, the two sides of the upper end of the base layer are provided with a first supporting column and a second supporting column respectively, and a first graphene layer, an insulating layer and a second graphene layer are sequentially arranged at the upper end of the first supporting column and the upper end of the second supporting column; the electro-optic modulator further comprises a first electrode, a second electrode and the D-type superfine optical fibers, the first electrode is located on the outer side above the first supporting column and directly connected with the first graphene layer, the second electrode is located on the outer side above the second supporting column and directly connected with the second graphene layer, and the polishing surface of the D-type superfine optical fiber is attached to the middle of the upper surface of the second graphene layer. According to the graphene absorption-type electro-optic modulator based on the D-type superfine optical fiber, the D-type polished superfine optical fiber is utilized to serve as a modulation area, sufficient interaction can be achieved between graphene and light, and therefore effective optical-wave modulation can be achieved through smaller device size; the electro-optic modulator has the advantages of being high in modulation speed, low in power consumption, simple in preparation technology and easy to achieve.

A closed loop power converter circuit of a UPS or other power supply includes a pulse width modulator circuit in a forward path of the closed loop power circuit. A compensation circuit provides pulse width commands to the pulse width modulator at a first rate. A feedback circuit digitally filters samples of an output of the closed loop power converter at a second rate greater the first rate and that provides the filtered samples to the compensation circuit. In some embodiments, the compensation circuit may be operative to compensate for the phase lag associated with a low pass output filter.

An optical signal is produced from a direct modulation resonant cavity device, such as directly-modulated diode laser having an electrode divided into multiple sections. Each section is driven with an electrical waveform such that a time delay is introduced between sections so as to ensure that the different sections reach their peaks at slightly different times.

The invention discloses an optical signal transmission method and system used for an indoor wireless network, and relates to the field of optical fiber communication. The method includes following steps: a downlink optical signal transmission process: an optical signal transmitting terminal splits externally transmitted optical signals, performs beam expanding on the split optical signals, performs phase modulation on the optical signals according to a preset downloading wavelength and issues the modulated optical signals to user terminals; and an uplink optical signal transmission process: the optical signal transmitting terminal performs phase modulation on optical signals uploaded by the user terminals, focuses the optical signals after phase modulation, and couples the optical signalsto the external. According to the method and system, a wireless communication device is not adopted, direct transmission of the optical signals with non-changeable wavelength can be realized, the security performance of transmission of the optical signals is enhanced, and an optical fiber network is directly applied to the indoor wireless network.

The invention discloses a non-volatile tunable directional coupler based on a phase change material. The coupler comprises an SOI substrate, the SOI substrate is provided with a parallelly distributedinput silicon waveguide and an output silicon waveguide in a horizontal direction, the coupler is characterized in that the upper surface of an output silicon waveguide is provided with a phase change material GST waveguide layer in the length direction, the GST waveguide layer is located in the coupling region and is uniformly divided into N segments, each segment can work in a crystalline or amorphous state, the N is any natural number within 3-20, the coupler achieves any ratio of power coupling by changing the number of segments of the GST waveguide layer in crystalline and amorphous state, and the coupler has the advantages of on-chip integration, low energy consumption, wide operating bandwidth, low insertion loss and the tunable output power.

The invention discloses an all-optical modulation device based on a micro-nano GaAs optical waveguide. The all-optical modulation device comprises a laser light source, an optical fiber coupler, micro-nano GaAs optical waveguide and a filter, wherein the laser light source, the optical fiber coupler, the micro-nano GaAs optical waveguide and the filter are sequentially connected with one another through optical fibers. All-optical modulation signals realized by applying the all-optical modulation device has higher modulation depth and extinction ratio, the modulation rate reaches as high as dozens of Gb/s, and important performance parameters of modulated signals such as modulation depth and extinction ratio can be flexibly controlled by a pump light intensity adjusting method, a pump light-probe beam frequency detuning method and other methods. The all-optical modulation technology realized by the invention can be used in an integrated optoelectronic technology for effectively reducing the module scale of an optical modulator and improving the modulation rate and the modulation depth.