Shanghai Jiao Tong University

General Electric Company

3m Innovative Properties Company

Jiao Liu

David Grey Smith

Gilles J Benoit

Jianping Chen

Linjie Zhou

Liangjun Lu

Weihan Xu

Zhuohui Tan

Timothy J Hebrink

Guanglei Du

Wei Ren

Qi Li

Liang Hu

Xueqin Wu

Onur Sinan Yordem

Guiling Wu

Jingfei Chen

Xinhui Wu

Wuhua Li

Gilles J B Benoit

Yan Yan Zhang

Yuxiang Wang

Wensheng Shan

Bo Guo

Dan Hou

Junjie Du

Chen Zhu

Yunjie Gu

David Smith

A calibration system and related methods for optical phased array chips. The calibration system includes an adjustable mount module, an infrared microscopic observation module, an arrayed driver module, a two-dimensional laser beam scanning module, a photoelectric conversion module and an upper computer, and utilizes computer-vision-enabled positioning and phase error compensation algorithms as software components. Collimated laser is emitted from the target beamforming angle and aimed at the emission aperture of the chip, and is subsequently sampled by the array elements in a reversed injection manner. Based on the reciprocity of light propagation, by maximizing the power reversely output from the bus waveguide of the optical phased array chip, beamforming at the target angle is achieved supported by software implementations of optimization algorithms. The system and related methods are readily achievable, highly automated, and offers fast and batch calibration with relatively low expenses, good flexibility and long-term compatibility.

Calibration system and method for integrated optical phased array chip

An optical millimeter wave terahertz transfer system and transfer method are disclosed. The device comprises a local terminal, a transfer link, an access terminal, and a user terminal. By using the device in the transfer link, optical signals transferred forward and backward are extracted through optical couplers, and millimeter wave terahertz signals with a stable phase are obtained at any position in the transfer link through optical signal filtering, photovoltaic conversion, microwave filtering, frequency division and optical frequency shift processing. The device and method have the characteristics of high reliability, simple structure, and low implementation cost.

Distributed optical millimeter wave terahertz transfer system and transfer method

A chip-scale silicon-based hybrid-integrated LiDAR system, wherein a transmitting end thereof sequentially comprises a narrow-linewidth tunable laser source, a silicon-nitride-based beam splitter, a silicon-based phase shifter array and a silicon-nitride-based unidirectional transmitting antenna array w.r.t the optical path. Based on the principle of reciprocity of light propagation, the receiving end thereof sequentially comprises a silicon nitride unidirectional receiving antenna array, a silicon nitride beam splitter and a silicon-based coherent receiving module. It also comprises a backup system and an electric controller as the driver of the phase shifters and the processing module. Modules on the silicon platform and the silicon nitride platform are monolithic integrated in a multilayer sandwiched fashion by means of a tapered silicon/silicon nitride evanescent inter-layer coupler; and a gain chip in the tunable laser module and a silicon nitride waveguide are hybrid-integrated by horizontal coupling.

Chip-scale silicon-based hybrid-integrated LiDAR system

A three-dimensional scanning LiDAR based on one-dimensional optical phased arrays comprises a transmitting end, a coherent receiving end and an incoherent receiving end, wherein the transmitting end, the coherent receiving end and the incoherent receiving end are all one-dimensional arrays. A phase control complexity of the three-dimensional scanning phased array is reduced, and a tunable laser with high cost and a grating array antenna with large crosstalk are avoided. The LiDAR provides pure solid-state three-dimensional scanning in speed and integration level and is highly practical.

Three-dimensional scanning LiDAR based on one-dimensional optical phased arrays

Integrated two-dimensional multi-beam LiDAR transmitter based on the Butler matrix, comprising an tunable laser array, a frequency modulated continuous wave modulator array, an N×N Butler optical matrix network, an N×M optical beam expanding network, an M-path phase shifter array, and an M-path two-dimensional LiDAR emitters. N-path narrow linewidth continuous light output by the tunable laser array passes through the frequency modulated continuous wave modulator array to generate N-path frequency modulated continuous light signals; after processed by the N×N Butler matrix and the N×M optical beam expanding network, energy of each path of the frequency modulated continuous optical signal is evenly distributed to the M-path output ports, and the M-path phase shifter array generates equal-difference phases with continuously tunable phase differences for M-path optical signals, which, with continuously tunable phase differences, are transmitted by M-path two-dimensional LiDAR emitters to realize no more than N different two-dimensional steerable transmitting optical beams.

Integrated two-dimensional multi-beam lidar transmitter based on butler matrix

A silicon Fourier transform spectrometer and an optical spectrum reconstruction method are disclosed. The spectrometer includes a waveguide input coupler, cascaded optical switches, unbalanced subwavelength grating (SWG) waveguide pairs, and a germanium silicon detector, where the cascaded optical switches are connected through unbalanced SWG waveguide pairs. The state of the optical switches are adjusted to digitally configure the optical path, so as to constitute a series of unbalanced Mach-Zehnder interferometer (MZI) arrays with different optical path differences, to realize a Fourier transform spectrometer based on spatial heterodyne. The optical spectrum is reconstructed by using a compressed sensing algorithm.

Silicon fourier transform spectrometer and optical spectrum reconstruction method

A silicon- and optical phased array-based integrated optically adjustable delay line, comprising, an optical phased array transmitting unit, a slab waveguide transmitting unit, and an optical phased array receiving unit that are sequentially arranged. By the optical phase control transmitting unit, the phase difference between channels is regulated and controlled via a phase shifter to change a far-field interference light spot and form a wave beam with directivity to regulate and control an incident angle of an optical signal entering the slab waveguide, thus changing the propagation path length of the optical signal. Finally, the optical signal is received by a corresponding optical phased array receiving unit to obtain different delay amounts. Large adjustable delay amount is realized and the delay line has the advantages of simple structure and control and high integration level with high application value in optical communication and microwave photonic and optical signal processing.

Silicon-based integrated optically adjustable delay line based on optical phased array

The present invention discloses a power generation system including a double-fed induction generator, a power converter, and a controller. The double-fed induction generator includes a rotor and a stator coupled to a grid. The power converter includes a rotor side converter coupled to the rotor of the generator, a grid side converter coupled to the grid, and a DC bus coupled between the rotor side converter and the grid side converter. The controller includes a rotor side controller for controlling the rotor side converter and a grid side controller for controlling the grid side converter. The rotor side controller includes a compensator having a transfer function and configured to counter a negative resistance effect of the generator to suppress sub-synchronous oscillations. The present invention further discloses a system for suppressing sub-synchronous oscillations and a method for controlling operation of a power system.

Power generation system, system for suppressing sub-synchronous oscillation and method for controlling operation of power system

Multi-layered solar cell devices covered with partially transmissive graphic films. The multi-layered solar cell devices include at least one solar cell, a graphics layer over the solar cell, and a reflective layer. The reflective layer can be behind the solar cell for recycling light or between the partially transmissive graphic film and the solar cell for improved appearance. The multi-layered solar cell devices have a high efficiency and a customizable appearance.

Multi-layered solar cell device

A power conversion system is disclosed including a DC bus for receiving DC power, a power converter for converting the DC power to AC power, and a controller. The controller includes an active power regulator for generating a phase angle command signal, a reactive power regulator for generating a voltage magnitude command, and an active power (P) and reactive power (Q) decoupling unit for decoupling interaction between the active and reactive power regulators. The PQ decoupling unit includes an active power compensation element and a reactive power compensation element. The active power compensation element is used for generating a phase angle compensation signal based on a reactive power error signal, to compensate the phase angle command signal. The reactive power compensation element is used for generating a voltage magnitude compensation signal based on an active power error signal, to compensate the voltage magnitude command signal.

Power decoupling controller and method for power conversion system

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Shanghai, China

Jiao Liu