In an embodiment, an apparatus includes a transmit section including a first baseband section and a first radio frequency (RF) section, wherein the transmit section is configured to receive a calibration signal, the first RF section is configured to generate a RF calibration signal based on modulating the calibration signal. The calibration signal comprises an orthogonal code based signal; and a receive section configured to receive the RF calibration signal over-the-air, the receive section includes a second RF section and a calibration section, the second RF section is configured to generate a received calibration signal based on the RF calibration signal, the received calibration signal and a reference signal associated with the RF calibration signal comprise inputs to the calibration section and the calibration section is configured to determine one or more of gain, baseband delay, or RF delay compensation values, based on the inputs, to calibrate the transmit section.

In an embodiment, a communications system includes a first transmitter including a digital beamforming baseband section configured to receive an input signal to be transmitted, the input signal at a baseband frequency, and a modulation section electrically coupled to the digital beamforming baseband section and a first antenna of a phased array antenna. The modulation section is configured to receive a local oscillator signal at a first local oscillator frequency and apply a baseband frequency shift to the input signal to generate a baseband frequency shifted input signal. The modulation section generates a modulated signal based on the input signal. The communication system includes a second transmitter included in a second IC chip of the plurality of IC chips electrically coupled to a second antenna and configured to provide a second modulated signal at the carrier frequency and a second LO leakage signal at a second local oscillator frequency.

In an embodiment, a communications system includes a first transmitter including a digital beamforming baseband section configured to receive an input signal to be transmitted, the input signal at a baseband frequency, and a modulation section electrically coupled to the digital beamforming baseband section and a first antenna of a phased array antenna. The modulation section is configured to receive a local oscillator signal at a first local oscillator frequency and apply a baseband frequency shift to the input signal to generate a baseband frequency shifted input signal. The modulation section generates a modulated signal based on the input signal. The communication system includes a second transmitter included in a second IC chip of the plurality of IC chips electrically coupled to a second antenna and configured to provide a second modulated signal at the carrier frequency and a second LO leakage signal at a second local oscillator frequency.

A passive vector modulator (PVM) includes a divider that splits an input signal into a first divided signal and a second divided signal 90° apart in phase. The PVM includes a switched transformer phase shifter including primary windings to form first primary windings and second primary windings receiving the first divided signal and the second divided signal respectively. First secondary windings are coupled to the first primary windings, the first secondary windings being center-tapped and outputting first and second phase shifted output signals, phase shifted 180° and 0° respectively. Second secondary windings are coupled to the second primary windings, the second secondary windings being center-tapped and outputting third and fourth phase shifted signals, phase shifted 270° and 90° respectively. The PVM includes a switch configured to receive the phase shifted output signals. The switch selectively outputs one of the phase shifted output signals, or a combination, from the PVM.

A passive vector modulator (PVM) includes a divider that splits an input signal into a first divided signal and a second divided signal 90° apart in phase. The PVM includes a switched transformer phase shifter including primary windings to form first primary windings and second primary windings receiving the first divided signal and the second divided signal respectively. First secondary windings are coupled to the first primary windings, the first secondary windings being center-tapped and outputting first and second phase shifted output signals, phase shifted 180° and 0° respectively. Second secondary windings are coupled to the second primary windings, the second secondary windings being center-tapped and outputting third and fourth phase shifted signals, phase shifted 270° and 90° respectively. The PVM includes a switch configured to receive the phase shifted output signals. The switch selectively outputs one of the phase shifted output signals, or a combination, from the PVM.

A liquid crystal phase shifter, a liquid crystal antenna, a communication apparatus, and a method for operating a liquid crystal phase shifter are provided. The liquid crystal phase shifter includes a microwave transmission structure and a phase adjustment structure opposite to each other, and a liquid crystal layer between the microwave transmission structure and the phase adjustment structure; wherein the phase adjustment structure comprises a plurality of phase adjustment units; the plurality of phase adjustment units are configured to change a dielectric constant of the liquid crystal layer according to a voltage applied to the phase adjustment units and a voltage applied to the microwave transmission structure, so as to adjust a phase of a microwave signal; and phase shift amounts adjusted by the plurality of phase adjustment units are different from each other.

Systems, methods, and non-transitory media are provided for cross-coupling modeling and compensation. An example method can include determining one or more cross-coupling coefficients representing electrical cross-coupling within a component of a phased array antenna, wherein the component of the phased array antenna includes one or more signal paths between one or more beamformers of the phased array antenna and a set of antenna elements of the phased array antenna; based on the one or more cross-coupling coefficients, modifying one or more beamforming weights calculated for one or more signals routed via the one or more signal paths, wherein the modified one or more beamforming weights compensate for the electrical cross-coupling effect within the component of the phased array antenna; and applying, by the one or more beamformers, the modified one or more beamforming weights to the one or more signals routed via the one or more signal paths.

An antenna module includes digital phase shifters, a plurality of antenna elements arranged in a first direction, and a fixed phase shifter. Each of the digital phase shifters changes a phase of a signal to a first phase value. The fixed phase shifter changes a phase of a signal to a second phase value, the second phase value being obtained by adding a predetermined offset phase value to the first phase value. A middle point of a virtual line is an antenna center and connects a center of an antenna element located on an end in the first direction and a center of an antenna element located on a different end. Under a symmetrical condition, an antenna center among the plurality of antenna elements are paired as an antenna element pair, the fixed phase shifter is electrically connected to at least one antenna element of the antenna element pair.

An antenna module includes digital phase shifters, a plurality of antenna elements arranged in a first direction, and a fixed phase shifter. Each of the digital phase shifters changes a phase of a signal to a first phase value. The fixed phase shifter changes a phase of a signal to a second phase value, the second phase value being obtained by adding a predetermined offset phase value to the first phase value. A middle point of a virtual line is an antenna center and connects a center of an antenna element located on an end in the first direction and a center of an antenna element located on a different end. Under a symmetrical condition, an antenna center among the plurality of antenna elements are paired as an antenna element pair, the fixed phase shifter is electrically connected to at least one antenna element of the antenna element pair.

A field-assembled satellite communications terminal has a plurality of discrete, modular aperture blocks. Each aperture block contains an electrically steered antenna aperture, and a plurality of interconnection ports for power and data communications between the plurality of aperture blocks. The plurality of interconnection ports are removably connectable by the end user in the field, The terminal further has a signal processing system for receiving, processing, and generating signals to and from the apertures. The aperture blocks are connected to each other in the field and self-configure to form an electrically-steered antenna,