A system of architecture, apparatus and calibration method is invented for high-power flexible-polarization payload for satellite communications. The system comprises onboard phase-tracked apparatus, flexible polarization mechanism, and in-orbit calibration method. The power combining and polarization performance of the phase-tracked payload is monitored on ground by measuring the cross-polarization discrimination (XPD) and/or axial ratio (AR). The high performance over the life is achieved by optimization of the XPD or AR on ground and adjusting complex gain of the transponders. The high-power flexible-polarization in-orbit-calibration payload may be applied but not limited to UHF, L, S, C, X, Ku and Ka-band high power satellite systems.

A Global Navigation Satellite System (GNSS) receiver that includes a satellite signal generator generating signal data for a signal that is not being tracked by the receiver. The receiver includes a satellite signal generator running an algorithm to process first and second received signals to produce a software-synthesized satellite signal, and the generated signal data is used to correct bias or is communicated to a spaced-apart GNSS receiver or used for onboard positioning calculations. The satellite constellation may be the Galileo constellation, with the first and second signals being E5A and E5B signals tracked by the receiver and the generated third signal being an E5AltBOC signal. With a half-a-cycle bias resolution technique, the satellite signal generator generates synthetic E5AltBOC data of high quality. For a receiver, which physically tracks E5AltBOC, synthetic E5AltBOC may be used to monitor polarity of a physically tracked E5AltBOC and correct it if error is detected.

In RTK positioning, a calibration memory stores calibration information for combinations of GNSS receivers. A memory processor retrieves the calibration information for a selected combination of a first GNSS receiver for a base station and a second GNSS receiver for a rover from the calibration memory. A calibration apparatus, by communicating with the rover and the memory processor, receives a first correction signal associated with the first GNSS receiver, obtains the calibration information and modifies the first correction signal therewith to generate a modified correction signal calibrated for the second GNSS receiver with respect to the first GNSS receiver, and transmits the modified correction signal to the rover. The rover performs the RTK positioning with respect to a known GNSS receiver of the base station using the modified correction signal, thereby automatically achieving the frequency-dependent hardware bias calibration for the second GNSS receiver with respect to the first GNSS receiver.

The present teaching relates to apparatus, method, medium, and implementations for initiating sensor calibration. A first GPS signal is received by a GPS receiver residing in an ego vehicle and is used to determine a first geo-position of the ego vehicle. A GPS related signal transmitted by a fiducial marker is received and is used to obtain a second geo-position of the fiducial marker. A distance between the ego vehicle and the fiducial marker is determined based on the first and second geo-positions and is used to determine whether to initiate calibration of one or more sensors using the fiducial marker.

An apparatus provides independent precise positioning for a reference station including a GNSS antenna and a GNSS receiver. The GNSS receiver generates GNSS data based on a plurality of GNSS signals received at the GNSS antenna, including GNSS signals having augmentation information. The apparatus includes a positioning processor, a signal processor, and a signal transmitter. The positioning processor calculates a current position of the reference station based on GNSS observation data and GNSS augmentation data obtained from the augmentation information included in the received GNSS signals, without using position information of another reference station, whereby the reference station is independently installed at a desirable location without surveying or measuring the desirable location. The signal processor generates error correction information including the current position of the reference station in a predetermined data format such as RTCM or CMR, based on the GNSS augmentation data.

An electronic device, a method, and a chipset for receiving global navigation satellite system (GNSS) signals are provided. An input/output (I/O) mixer including a first multiplier and a second multiplier downconverts a modulated radio frequency wave to an intermediate frequency. The modulated radio frequency wave is input to first inputs of the first multiplier and the second multiplier, and where an in-phase signal, from a first digital to analog converter (DAC), and a quadrature phase signal, from a second DAC, are input to second inputs of the first multiplier and the second multiplier, respectively. A mixer imbalance between the first mixer and the second mixer is reduced using direct current (DC) bias voltages from the first DAC and the second DAC. The DC bias voltages are determined based on a first and second DAC codes of the first and second DACs. The downconverted modulated radio frequency wave is filtered.

There is disclosed a method which is capable of calibrating or tuning the characteristics of individual antenna elements constituting an array antenna. The performance of the individual antenna elements can be improved by calibrating or tuning the characteristics of the individual antenna elements, and thus an array antenna can be installed even in a narrow space and can receive GPS signals.

Techniques described herein address these and other issues by utilizing two or more sensors to take temperature measurements from which a temperature-differential or instantaneous temperature rate-of-change, can be determined. In turn, this can be used to make a highly accurate model of the relationship between the temperature, temperature-differential, and clock circuitry frequency, to accurately estimate the frequency rate-of-change for frequency correction/compensation.

A system and method provide automatic RF path gain calibration independent of RF interference levels to preserve solution trust capabilities. After a system is powered ON, or a new antenna is attached (hot swap), a smart antenna assembly combined with a jammer power estimator within an RF receiver functions to autonomously measure internal gains within the RF path, calibrate the new antenna installation, and thereby measure a level of interference associated with the external environment from that point forward. A controller commands the antenna calibration retrieving antenna details and RF path gain calibration while measuring local jamming at the receiver input. Should the controller determine a level of jamming effectiveness is present, it offers a user a display of the local jamming levels enabling the user accurate theater decision making regarding the accuracy and availability of desirable signal.

A system for time synchronization of a network element including a GNSS receiver operative to receive at least one signal from at least one but less than four GNSS satellites, a locator operative to supply a location of a network element including the GNSS receiver to the GNSS receiver and a time synchronization calculator operative to time synchronize the network element with the GNSS satellites based on the at least one signal and the location.