Abstract: In an embodiment, a power delivery system includes a first current limiter and a second current limiter in parallel with each other, wherein a direct current (DC) voltage is provided to each of the first current limiter and the second current limiter; a first transformer electrically coupled to the first current limiter; a second transformer electrically coupled to the second current limiter; first differential signal traces electrically coupled to the first transformer; and second differential signal traces electrically coupled to the second transformer, wherein the DC voltage is transmitted from the first transformer to the first differential signal traces simultaneous with the DC voltage being transmitted to the second differential signal traces by the second transformer.

Abstract: An antenna calibration system for a phased array antenna in accordance with one embodiment of the present disclosure generally includes: a beamformer corresponding to a subset of antenna cells of a plurality of antenna cells, wherein the beamformer includes a calibration section for comparing a reference signal to a non-reference signal and a first operating antenna within the subset of antenna cells corresponding with the beamformer. In some implementations, the first operating antenna is configured to deliver a first reference signal (mTx) from the beamformer to be received by a second operating antenna for comparison with a first non-reference signal (Rx) in the beamformer, and/or the first operating antenna is configured to deliver a second non-reference signal (Tx) from a third operating antenna for comparison with a second reference signal (mRx) in the beamformer.

Abstract: A modem is configurable on a satellite, user terminal or gateway generates a radio frequency (RF) signal using an orthogonal frequency division multiplexing (OFDM) protocol including a radio frame including one or more bursts. A burst of the one or more bursts includes a first portion including burst detection data, a second portion including channel characteristic estimation data, a third portion including payload data, and fourth and fifth portions including pilot data. The first portion in a time domain is included in the burst prior to the second, third, fourth, and fifth portions. The first portion can include a pseudo-random noise sequence inserted in the time domain. The same physical modem can be configured to transmit signals on an uplink or downlink between a user terminal and a satellite or on the uplink or downlink between the satellite and the gateway.

Abstract: In one embodiment of the present disclosure, a satellite communication system includes a satellite constellation including a plurality of satellites in non-geosynchronous orbit (non-GEO), wherein at least some of the plurality of satellites travel in a first orbital path at a first inclination, and an end point terminal having an earth-based geographic location, the end point terminal having an antenna system defining a field of regard for communicating with the satellite constellation, wherein the field of regard is a limited field of regard, wherein the field of regard is tilted from a non-tilted position to a tilted position, and wherein the tilt angle of the tilted position is a function of the latitude of the geographic location.

Abstract: In an embodiment, an apparatus includes a first baseband section to receive a calibration signal; a first radio frequency (RF) section configured to generate a RF calibration signal based on modulating the calibration signal. The calibration signal comprises an orthogonal code based signal. The apparatus includes a second RF section to receive the RF calibration signal and generate a received calibration signal based on demodulating the RF calibration signal; a calibration section; a first antenna electrically coupled to the first RF section and configured to transmit the RF calibration signal; and a second antenna electrically coupled to the second RF section and configured to receive the RF calibration signal. The calibration section is configured to determine one or more of gain, baseband delay, or RF delay to calibrate the first RF section; and the second antenna is switchable between receiving the RF calibration signal and transmitting an encoded data signal.

Abstract: In an embodiment, a user terminal includes a communication module (CM) configured to generate an initial network entry request; an antenna assembly configured to find, in response to the initial network entry request, a satellite based on a search of a sky. The search of the sky includes sequentially changing a beam pointing direction of the antenna assembly. The satellite is assigned to downlink to a geographic cell associated with the user terminal. The user terminal includes a media access control (MAC) layer component configured to generate an uplink radio frame including a random access channel (RACH) request associated with the initial network entry request at a particular portion of the uplink radio frame for the satellite.

Abstract: An antenna assembly in accordance with one embodiment of the present disclosure includes a stack patch antenna assembly defining a plurality of antenna cells made from a plurality of patches, wherein the stack patch antenna assembly includes a first patch layer separated from a second patch layer by a spacer; a beamformer lattice including one or more beamformers, wherein each beamformer corresponds to a subset of antenna cells of the plurality of antenna cells; and a PCB assembly made up from a plurality of layers, the PCB assembly having a feed structure from the stack patch antenna assembly to the beamformer lattice disposed in the PCB assembly, wherein the stack patch antenna assembly is external to the PCB assembly.

Abstract: In an embodiment, a method includes determining a first beam pointing vector associated with an antenna assembly by searching for a satellite from a plurality of satellites. The method includes maintaining a communication link with the satellite by determining a plurality of beam pointing vectors that converge to a signal quality value. The method includes obtaining, from the satellite, satellite ephemeris information of the satellite and one or more of remaining satellites of the plurality of satellites. The method includes determining an estimated orientation of the antenna assembly based on one or more of the satellite ephemeris information and the plurality of beam pointing vector. The method includes determining a second beam pointing vector based on the estimated orientation, the satellite ephemeris information, and an approximate position information of the antenna assembly.

Abstract: In an embodiment, an apparatus includes one or more timing components configured to generate a reference time signal based on a timing signal and a reference clock signal. The apparatus includes phase lock loop (PLL) configured to generate a synchronized output clock signal based on the reference clock signal and the reference time signal.

Abstract: In an embodiment, an apparatus includes an integrated circuit (IC) chip configured to receive a timing signal and a first reference clock signal and generate a first reference time signal based on the timing signal and the first reference clock signal. The IC chip is configured to generate a second reference time signal based on the first reference time signal and a second reference clock signal, different from the first reference clock signal The second reference time signal specifies a count of a number of cycles of the second reference clock signal starting from a particular cycle of the second reference clock signal. The IC chip is configured to synchronize one or more actions performed by the IC chip based on one or more of the first reference time signal or the second reference time signal.

Abstract: In an embodiment, an apparatus includes a first digital beamformer (DBF) associated with a first subset of antennas of a phased array antenna, the first DBF including a transmit section associated with transmission of a first signal at a first frequency in a transmit mode and a receive section associated with receiving of a second signal at a second frequency in a receive mode, the second frequency being different from the first frequency. The apparatus includes a second DBF associated with a second subset of antennas of the phased array antenna. The first and second DBFs are configured to receive a local oscillator signal having the first frequency from a common local oscillator in the transmit mode and receive the local oscillator signal having the second frequency from the common local oscillator in the receive mode.

Abstract: A wireless communications system includes a pre-distortion actuator configured to receive a carrier-modulated signal and convert the carrier-modulated signal into an output signal, the pre-distortion actuator comprising a behavioral model that models a transmit chain of the system including at least one amplifier and at least one antenna and predict an input-output relationship of the transmit chain of the system between an input to the transmit chain to an output of the transmit chain. The system includes a phased antenna array configured to transmit the output signal. The phased antenna array includes a plurality of antenna elements, each antenna element electrically coupled to a respective power amplifier. The pre-distortion actuator is configured to generate the output signal by applying a correction to the carrier-modulated input signal that cancels out nonlinearities The behavioral model is updated based on feedback from a receiver from a previous output signal transmitted to the receiver.

Abstract: Systems, methods, and techniques are provided for a radio link control (RLC) sublayer. An example satellite or user terminal can include a divisional of layer 2 of the OSI protocol layer structure. An example method includes providing a RLC sublayer on top of a MAC sublayer and adaptively switching, via the RLC sublayer and based on external data, between an unacknowledged mode and an acknowledged mode for the electronic communications. If the RLC sublayer is operating in the unacknowledged mode, the RLC sublayer provides one or more of (1) fragmentation and reassembly of service data units; (2) a use of RLC headers; and/or (3) no delivery guarantees. If the RLC sublayer is operating in the acknowledged mode, the RLC sublayer provides reliability in a sequence delivery service and one or more of (1) fragmentation and reassembly of service data units; and/or (2) the use of RLC headers.

Abstract: Systems, methods, and non-transitory media are provided for cross-coupling modeling and compensation.

Abstract: An apparatus includes a plurality of conductive structures having first sides and second sides opposite the first sides, wherein the second sides of the plurality of conductive structures are configured to be physically coupleable with a printed circuit board (PCB) of a receiver, a transmitter, or a transceiver. The first sides of the plurality of conductive structures are configured to be spaced from the PCB by a first distance when the plurality of conductive structures is physically coupled with the PCB. The apparatus includes an antenna having a first side and a second side opposite the first side. The second side of the antenna is disposed closer to the plurality of conductive structures than the first side of the antenna when the plurality of conductive structures is physically coupled with the PCB.