H04B10/503

REFLECTIVE GAUSSIAN TO FLAT-TOP AND OTHER BEAM SHAPERS
20230018018 · 2023-01-19 ·

An apparatus includes a reflective beam shaper configured to receive an input optical signal having a first energy distribution and generate an output optical signal having a second energy distribution different from the first energy distribution. The reflective beam shaper includes multiple reflective mirrors including a first mirror and a second mirror. The first mirror may include a first aspheric reflector configured to reflect the input optical signal as a first intermediate optical signal having a changing energy distribution. The second mirror may include a second aspheric reflector configured to reflect one of the first intermediate optical signal or a second intermediate optical signal as the output optical signal. A third mirror may include a third aspheric reflector configured to reflect the first intermediate optical signal as the second intermediate optical signal having another changing energy distribution.

Signal processing apparatus and signal processing method
11700064 · 2023-07-11 · ·

This application provides example signal processing apparatus and example signal processing method. One example signal processing apparatus includes a sampling unit, a beam combiner, and an optical resonator. The sampling unit is connected to the beam combiner, and the beam combiner is connected to the optical resonator. The sampling unit is configured to sample an analog signal by using an optical pulse signal to output a sampled optical pulse signal. The beam combiner is configured to combine the sampled optical pulse signal and a multi-wavelength optical signal into a first optical signal. The optical resonator is configured to perform resonance based on the first optical signal to output a second optical signal in the first optical signal, where a wavelength of the second optical signal is equal to a resonant wavelength of the optical resonator.

HIGH SPEED COMMUNICATION

A system and method for high speed communication are provided. The system comprises a laser-based system for communication, the system comprising: an acquisition module configured to acquire and characterize a plurality of laser beams; a tracking module configured to track the acquired laser beams, the tracking module comprising: a beaconing feedback and beam divergence mechanism configured to control a beam and detect a beam; an adaptive learning unit configured to implement an adaptive learning detection algorithm to identify and track a unique optical signature from at least one of the acquired laser beams; and a pointing module configured to point at least one laser beam towards a target based on the acquired laser beams.

Radio Access Network using Radio Over Fibre
20230216587 · 2023-07-06 ·

A radio communication system for duplex communication comprising an optical carrier generator for generating optical carrier signals, a local oscillator (LO) for generating an electrical signal in a radio communication band, an information signal source, electro-optic modulators driven directly at an input electrical port by said information signal and said LO signal to modulate a portion of said optical carrier signal to form a modulated portion being an optical band information signal for transmission over an optical link; and a photodetector remote from said electro-optic modulators for receiving said transmitted optical band information signal from said optical link, and directly generating an electrical signal that is up-converted for radio transmission, or down-converted to a baseband frequency.

FREQUENCY GRADIENT METASURFACE-BASED FAST BEAM STEERING TRANSMISSION METHOD AND APPARATUS FOR OWC
20230216592 · 2023-07-06 · ·

The present specification provides a method and apparatus, the method being for transmitting a beam, performed by the apparatus, in an optical wireless communication system, and comprising: generating a pulse laser signal; making the pulse laser signal to be incident on a metasurface, wherein the beam is generated on the basis that the pulse laser signal is incident on the metasurface; and transmitting the beam to a reception apparatus, wherein the metasurface is determined on the basis of ω_0, d, Δω, and N, wherein ω_0 is a value of a center frequency, d is a value of a virtual antenna interval, Δω is a value of a frequency comb interval, and N is a value related to the number of frequency combs present within a gain bandwidth based on the center frequency.

Time comparison system, time comparison device, and time comparison method

[Problem] To determine a time difference between clocks which, for example, are placed far apart from each other with high accuracy at low cost. [Solution] In a time comparison system 20, an intermediate station 21 disperses a single optical signal 21c in the spatial region using the optical complex amplitude modulation to simultaneously transmit the optical signal 21c to a plurality of comparative stations 22 and 23 apart from each other. The intermediate station 21 transmits the optical signal 21c while changing the transmission angle using phase modulation, performs intensity scanning for the reflected light c1 of the optical signal 21c, and detects the peak intensity to determine the directions of the comparative stations 22 and 23. The reflected light c1 of the optical signal 21c transmitted to the comparative stations 22 and 23 of which the direction have been determined, is detected to determine a round-trip propagation delay time between the intermediate station 21 and each of the comparative stations 22 and 23. The difference calculation unit 25 calculates a sum of time difference between each of times to and tb associated with the comparative stations 22 and 23 and the time tc associated with the intermediate station 21, and the determined propagation delay time to determine time information of each of the comparative stations 22 and 23. Based on the result of subtracting, from the time information of the comparative stations 22, the time information of the comparative stations 23, the time difference between the comparative stations 22 and 23 is determined.

High-speed optical transceiver integrated chip drive circuit with phase delay compensation function

A high-speed optical transceiver integrated chip drive circuit with phase delay compensation function includes a transmitting end drive circuit to drive the laser to emit light to transmit signals and a receiving end drive circuit to optimize the signal degradation caused by the signal sent by the transmitting end drive circuit to the laser via the transmission backplane; a long code phase lead adjustment circuit is arranged on the main channel of the transmitting end drive circuit, and a long code phase lag adjustment circuit is set on the main channel of the receiving end drive circuit. The present invention is used to optimize high-speed signals and solve the problem that the CML drive circuit at the receiving end or the laser drive circuit at the transmitting end cannot compensate the difference between the group delay and phase delay for the high-speed signal after passing through the backplane (Laser device).

Systems and methods for wafer-level photonic testing

A semiconductor wafer includes a semiconductor chip that includes a photonic device. The semiconductor chip includes an optical fiber attachment region in which an optical fiber alignment structure is to be fabricated. The optical fiber alignment structure is not yet fabricated in the optical fiber attachment region. The semiconductor chip includes an in-plane fiber-to-chip optical coupler positioned at an edge of the optical fiber attachment region. The in-plane fiber-to-chip optical coupler is optically connected to the photonic device. A sacrificial optical structure is optically coupled to the in-plane fiber-to-chip optical coupler. The sacrificial optical structure includes an out-of-plane optical coupler configured to receive input light from a light source external to the semiconductor chip. At least a portion of the sacrificial optical structure extends through the optical fiber attachment region.

MULTI-ELEMENT LASER-BASED FULL-DUPLEX FREE-SPACE OPTICAL TRANSCEIVER
20230006742 · 2023-01-05 ·

A free-space optical (FSO) transceiver having an optimum number of transmitters and receivers positioned in optimum locations on the transceiver plane to ensure maximum signal-to-interference and noise ratio (SINR) and to minimize the effects of vibration of the mobile platform and atmospheric turbulence. A defocal lens assembly having an adjustable distance between the transmitters and the lens assembly is further provided to maximize the optical coupling efficiency and the vibration tolerance by adjusting the defocusing length.

Systems and methods for chromatic dispersion pre-compensation

A method for chromatic dispersion pre-compensation in an optical communication network includes (1) distorting an original modulated signal according to an inverse of a transmission function of the optical communication network, to generate a compensated signal, (2) modulating a magnitude of an optical signal in response to a magnitude of the compensated signal, and (3) modulating a phase of the optical signal, after modulating the magnitude of the optical signal, in response to a phase of the compensated signal.