Systems and methods for calibrating a phase array antenna (“PAA”) are provided. The system includes a PAA having a plurality of array elements and a remote calibration terminal. The PAA is connected to a processor unit. The PAA includes a reference beamforming network (“BFN”) for generating a reference beam and a calibration BFN for generating a calibration beam. The PAA applies a plurality of scrambled orthogonal codes to the calibration BFN to generate the calibration beam. The remote calibration terminal is configured to analyze the reference beam and the calibration beam to determine a calibration error for the PAA, the calibration error including a phase error and an amplitude error for each of the plurality of array elements of the PAA. The remote calibration terminal may be configured to measure a beam pointing error (“BPE”) of the PAA and/or a coupling between array elements.

An electronic device may include a harmonic rejection mixer with a delay line, mixer array, and load. The delay line may generate LO phases. Each mixer in the array may have a first input that receives an LO phase and a second input coupled to an input switch and the first input of the next mixer circuit through an inter-mixer switch. The load may include a set of switches. In a transmit mode, the input switches and set of switches may be closed while the inter-mixer switches are open. In a self-calibration mode, the input switches and set of switches may be open while the inter-mixer switches are closed. A controller may sweep through phase codes for the programmable delay line while storing a digital output from the load. The controller may calibrate the phase code based on the digital output.

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, 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 method includes detecting, via first and second receivers of a tool that are oriented at a first and a third tilt angle, respectively, a first and second measurement of a first signal transmitted by a transmitter of the tool that is oriented at a second tilt angle into a substantially non-conductive material. The method includes determining, based on the first and second measurements, a first tensor and conveying the tool into a first wellbore formed in a subsurface formation. The method includes detecting, via the first receiver and the second receiver, a third and fourth measurement, respectively, of a second signal transmitted by the transmitter and determining, based on the third and fourth measurements, a second tensor and determining a third tensor (having values independent of the first, second, and third tilt angles) based on a relationship between the first and second tensors.

A method includes detecting, via first and second receivers of a tool that are oriented at a first and a third tilt angle, respectively, a first and second measurement of a first signal transmitted by a transmitter of the tool that is oriented at a second tilt angle into a substantially non-conductive material. The method includes determining, based on the first and second measurements, a first tensor and conveying the tool into a first wellbore formed in a subsurface formation. The method includes detecting, via the first receiver and the second receiver, a third and fourth measurement, respectively, of a second signal transmitted by the transmitter and determining, based on the third and fourth measurements, a second tensor and determining a third tensor (having values independent of the first, second, and third tilt angles) based on a relationship between the first and second tensors.

A transceiver is configured for a calibration mode of operation in which an impedance of a transmit chain is tuned responsive to a power measurement of a mixed RF calibration signal to form a tuned transmit chain. A direct conversion mixes an RF calibration signal with a DC offset signal to form the mixed calibration signal. During a normal mode of operation, a heterodyne mixer mixes an LO signal with an IF signal to produce an RF signal that is amplified through the tuned transmit chain.

A transmission method of simultaneously transmitting a first modulated signal and a second modulated signal at a common frequency performs precoding on both signals using a fixed precoding matrix and regularly changes the phase of at least one of the signals. One of signal generation processing in which phase change is performed and signal generation processing in which phase change is not performed is selectable, thereby improving general versatility in signal generation.