X Development LLC

Taara Connect, Inc.

Paul Csonka

Travis Lantz

Baris Ibrahim Erkmen

Devin Brinkley

Bruce Moision

Edward Allen Keyes

Klaus Ulander

Sanam Mozaffari

The technology relates to free-space optical communication systems that correct for errors in tracking and pointing accuracy to maintain connection integrity. Such systems can both proactively and reactively correct for errors in tracking performance and pointing accuracy of terminals within the system. An aspect includes receiving information indicative of at least one external disturbance associated with a communication device. A determination is made for a proactive estimation indicative of a first error associated with an effect of the at least one external disturbance at a current timestep. A determination is made for a reactive estimation indicative of a second error associated with the effect of the at least one external disturbance at a previous timestep. A final control signal is determined based on the proactive estimation and the reactive estimation. A controller is able to actuate an optical assembly of the communication device based on the determined final control signal.

Feedforward motion compensation for FSOC terminals

A communication device is provided that estimates one or more disturbance values associated with one or more components of the communication device, and adjusts the communication device to change a received power of the output signal. The communication device includes a transmitter having a seed laser configured to provide an amount of bandwidth for an output signal, an Erbium-doped fiber amplifier (EDFA) configured to increase an amplitude of the output signal, and a single mode variable optical attenuator (SMVOA) configured to decrease the amplitude of the output signal.

Power adjustment of a communication link based on state disturbance estimations

The disclosure provides for a method for reacquiring a communication link between a first communication device and a second communication device. The method includes using one or more processors of the first communication device to receive historical data related to the first communication device and an environment surrounding the first communication device. The one or more processors are then used to determine one or more trends in the historical data related to fading of the communication link. Based on the one or more trends, the one or more processors are used to determine a starting time and an initial search direction for a search for the communication link. The one or more processors then execute the search at the starting time from the initial search direction.

Reacquiring communication link based on historical data

The disclosure provides a method for adjusting an optical link alignment of a first communication device with a remote device. The method includes transmitting or receiving an optical signal; receiving one or more measurements of at least one environmental factor at the first communication device or the remote device; and receiving or detecting an apparent amount of alignment of the optical signal. Then, by one or more processors of the first communication device, determining an estimated error attributable to optical cross coupling and an actual amount of alignment of the optical signal based on the apparent amount of alignment and the estimated error. Next, adjusting the first communication device based on the actual amount of alignment to correct for optical cross coupling.

Algorithmic correction for optical cross-coupling

The technology employs a state-based power control loop (PCL) architecture to maintain tracking and communication signal-to-noise ratios at suitable levels for optimal tracking performance and data throughput in a free-space optical communication system. Power for a link is adjustable to stay within a functional range of receiving sensors in order to provide continuous service to users. This avoids oversaturation and possible damage to the equipment. The approach can include decreasing or increasing the power to counteract a surge or drop while maintaining a near constant received power at a remote communication device. The system may receive power adjustment feedback from another communication terminal and perform state-based power control according to the received feedback. This can include re-initializing and reacquiring a link with the other communication terminal automatically after loss of power, without human intervention. There may be a default state and discrete states including rain, fade, surge and unstable states.

Power control loop for stabilization of link power

The disclosure provides a system for transmitting and receiving optical signals. The system includes a first mirror of a communication device, a first mirror actuator configured to control a pointing direction of the first mirror, a second mirror of the communication device, a second mirror actuator configured to control a pointing direction of the second mirror, and one or more processors. The one or more processors are configured to direct the second mirror actuator to move the second mirror to track a signal within a zone in an area of coverage of the communication device and meanwhile keep the first mirror stationary at a first angle. The one or more processors are also configured to direct the first mirror actuator to move the first mirror to a second angle in a direction of motion of the signal when the signal reaches an edge of the zone and meanwhile move the second mirror to a default angle.

Two-mirror tracking system for free-space optical communication

The disclosure provides a communication system that includes sensors, a plurality of components, and processors. The sensors receive measurements related to a state of the communication system. The processors receive an indication of an amount of received power at a remote communication system and estimate a state of the plurality of components based on the received one or more measurements and the received indication. Using the indication and the estimated state, the processors determine whether the amount of received power is likely to fall below a minimum received power within a given time interval. When it is likely, the processors select an adjustment technique of a plurality of adjustment techniques for adjusting a data rate of the outbound signal and adjust a given component of the communication system using the selected adjustment technique to change the data rate of the outbound signal.

Adaptive rate modem

A free-space optical communication device includes an optical fiber bundle and one or more processors. The optical fiber bundle includes a central fiber connected to a first photodetector, and a plurality of surrounding fibers, each surrounding fiber connected to a corresponding second photodetector. The one or more processors are in communication with the first photodetector and each second photodetector. The one or more processors are also configured to receive a current or voltage generated at the first photodetector and each second photodetector and to determine a pointing accuracy of a beam received at the optical fiber bundle based on the current or voltage generated at the second photodetectors.

Determining pointing accuracy using optical fiber bundle

The disclosure provides for a communication system that includes one or more sensors and one or more processors. The one or more processors are configured to receive, during a first timeframe, a first indication of an error rate of a communication link, a second indication of an amount of received power at a remote communication system, and one or more measurements related to the state of the communication system. The one or more processors are then configured to estimate a plurality of disturbance values to the communication system according to the one or more measurements and the second indication. Each disturbance value is associated with a set of components of the communication system. The one or more processors are configured to adjust a beam divergence of a beacon beam or a communication beam transmitted from the communication system based on the plurality of disturbance values and the first indication.

Growing community of inventors

Redwood City, CA, United States of America

Paul Csonka