A method for suppressing a parasite signal received with a useful signal by a network of elementary antennas of a payload of a satellite. The suppression method includes an analogue formation step for forming analog beams and a digital formation step for forming a digital beam. The analog formation step includes forming of an useful analog beam in which the parasite signal is attenuated with respect to the useful signal and of an auxiliary analog beam in which the useful signal is attenuated with respect to the parasite signal. The digital formation step includes forming of a digital beam in which the parasite signal has been suppressed, by combining the signals obtained by digitizing the auxiliary beam and the useful beam.

A phase noise suppression method for a multiple-input multiple-output (MIMO) system with a plurality of co-reference channels includes: dividing the phase noise of each channel in the MIMO system into common phase noise and independent phase noise, and constructing a certain number of joint phase states for the independent phase noise; inserting a pilot sequence into the sent signal based on a preset cycle, obtaining the common phase noise based on the pilot at receiver, and performing compensation; and performing signal demodulation on each joint state of the independent phase noise, and comparing the posterior log likelihood values to select the optimal result to output. The above method can significantly improve the phase noise suppression performance of the MIMO system with a plurality of co-reference channels, thereby providing support for improving the system capacity by using MIMO technology.

A radio frequency receiver with adaptive dynamic filtering controlled by signals from subsequent or external circuit elements, as required to suppress undesired radio frequency energy, match the radio's input circuit to the received signal, and permit optimized processing of the signal of interest.

A phase noise suppression method for a multiple-input multiple-output (MIMO) system with a plurality of co-reference channels includes: dividing the phase noise of each channel in the MIMO system into common phase noise and independent phase noise, and constructing a certain number of joint phase states for the independent phase noise; inserting a pilot sequence into the sent signal based on a preset cycle, obtaining the common phase noise based on the pilot at receiver, and performing compensation; and performing signal demodulation on each joint state of the independent phase noise, and comparing the posterior log likelihood values to select the optimal result to output. The above method can significantly improve the phase noise suppression performance of the MIMO system with a plurality of co-reference channels, thereby providing support for improving the system capacity by using MIMO technology.

A transmitter circuit includes at least one transmitting signal processing device, a compensation device and a compensation value calibration device. The compensation device generates a first compensated input signal and a second compensated input signal by respectively processing input signals according to a first compensation value and a second compensation value. The transmitting signal processing device generates a first output signal and a second output signal by processing the first compensated input signal and the second compensated input signal. The compensation value calibration device receives the first output signal and the second output signal as a first feedback signal and a second feedback signal, respectively, and includes a digital signal processor. The digital signal processor determines a calibrated compensation value according to power of the first feedback signal and the second feedback signal at a predetermined frequency and the first compensation value and the second compensation value.

In some embodiments, a method for mitigating interference in a channel having multiple users includes: transmitting, by a transmitter, a signal of interest (SOI) to a sequential interference cancellation (SIC) receiver at a transmit power; determining a packet drop rate as seen by the receiver; and decreasing the transmit power in response to determining the packet drop rate exceeds a predetermined maximum packet drop rate. The transmitter's coding rate and/or modulation level may also be lowered based on the decrease in transmit power.

In some embodiments, a method for mitigating interference in a channel having multiple users includes: receiving a plurality of signals from a plurality of antenna elements, the received signals comprised of one or more interfering signals and a signal of interest (SOI); for each of the one or more interfering signals, beamforming the received signals to enhance the interfering signal, generating an estimate of the interfering signal, and adjusting the estimated interfering signal to undo the effects of beamforming; and subtracting each of the estimated interfering signals from each of the received signals to generate a plurality of interference-mitigated received signals.

Provided is a high frequency communication apparatus and method for vehicle. The high frequency communication apparatus for vehicle includes a communication module configured to process a radio frequency (RF) signal; a cable having one end connected to the communication module; and an antenna module connected to the other end of the cable and configured to transmit through an antenna the RF signal delivered from the communication module, the antenna module including a compensator configured to compensate for a loss of the RF signal in the cable and a controller configured to determine an amount of compensation for the loss in the cable based on power of the RF signal transmitted from the compensator.

A transmitter circuit includes at least one transmitting signal processing device, a compensation device and a compensation value calibration device. The compensation device generates a first compensated input signal and a second compensated input signal by respectively processing input signals according to a first compensation value and a second compensation value. The transmitting signal processing device generates a first output signal and a second output signal by processing the first compensated input signal and the second compensated input signal. The compensation value calibration device receives the first output signal and the second output signal as a first feedback signal and a second feedback signal, respectively, and includes a digital signal processor. The digital signal processor determines a calibrated compensation value according to power of the first feedback signal and the second feedback signal at a predetermined frequency and the first compensation value and the second compensation value.

A high-frequency front end module includes a primary antenna terminal and a secondary antenna terminal, a first multiplexer and a second multiplexer, a switch circuit, and a first amplifier and a second amplifier. The first multiplexer has a first transmission filter and a first reception filter. The second multiplexer has a second transmission filter and a second reception filter. The switch circuit exclusively switches connection between the primary antenna terminal and the first multiplexer and connection between the primary antenna terminal and the second multiplexer, and exclusively switches connection between the secondary antenna terminal and the first multiplexer and connection between the secondary antenna terminal and the second multiplexer.