Systems and methods disclosed herein provide techniques for reducing quantization errors and side lobe levels in phased array antennas. The states of a quantized phase shifter of a phased array antenna may be dithered to achieve a time-averaged value that reduces quantization errors. By rapidly switching between the different states of the quantized phase shifter, a time-average value close to a desired phase state may be achieved with a low resolution phase shifter.

Systems and methods disclosed herein provide techniques for reducing quantization errors and side lobe levels in phased array antennas. The states of a quantized phase shifter of a phased array antenna may be dithered to achieve a time-averaged value that reduces quantization errors. By rapidly switching between the different states of the quantized phase shifter, a time-average value close to a desired phase state may be achieved with a low resolution phase shifter.

Aspects of the subject disclosure may include, for example, a coupling device including a first antenna that radiates a first wireless signal conveying first data; and a second antenna that radiates a second RF signal conveying the first data from the at least one transmitting device. The first wireless signal and second RF signal form a combined RF signal that is bound by an outer surface of a transmission medium to propagate as a guided electromagnetic wave substantially in a single longitudinal direction along the transmission medium. Other embodiments are disclosed.

Aspects of the subject disclosure may include, for example, a coupling device including a first antenna that radiates a first wireless signal conveying first data; and a second antenna that radiates a second RF signal conveying the first data from the at least one transmitting device. The first wireless signal and second RF signal form a combined RF signal that is bound by an outer surface of a transmission medium to propagate as a guided electromagnetic wave substantially in a single longitudinal direction along the transmission medium. Other embodiments are disclosed.

An analog beamforming transmitter includes: a plurality of beamforming transmission circuits coupled in parallel between a signal input and an array of antenna ports, wherein the signal input is configured to receive an analog complex-valued communication signal having an in-phase and a quadrature component, wherein each antenna port of the array of antenna ports is configured to provide a dual-polarized antenna signal having a first polarization component and a second polarization component, wherein each beamforming transmission circuit is coupled between the signal input and a respective antenna port of the array of antenna ports, wherein each beamforming transmission circuit comprises a first coefficient input for receiving a first analog complex-valued beamforming coefficient a set of first analog complex-valued beamforming coefficients and a second coefficient input for receiving a second analog complex-valued beamforming coefficient of a set of second analog complex-valued beamforming coefficients.

Automatic frequency controllers, automatic frequency control methods, wireless communication devices, and/or wireless communication methods are provided. The automatic frequency controllers for correcting a frequency offset between a base station and a terminal includes at least one processor communicatively coupled to a memory and configured to execute computer-readable instructions stored in the memory to obtain a phase estimate from a reference signal received from the base station; classify a downlink channel as a High Speed Train (HST) channel or a non-HST channel based on the phase estimate; adjust a loop gain according to the classified downlink channel; calculate a phase error based on the phase estimate and the loop gain; correct the frequency offset using the phase error; and communicate with the base station after correcting the frequency offset.

Automatic frequency controllers, automatic frequency control methods, wireless communication devices, and/or wireless communication methods are provided. The automatic frequency controllers for correcting a frequency offset between a base station and a terminal includes at least one processor communicatively coupled to a memory and configured to execute computer-readable instructions stored in the memory to obtain a phase estimate from a reference signal received from the base station; classify a downlink channel as a High Speed Train (HST) channel or a non-HST channel based on the phase estimate; adjust a loop gain according to the classified downlink channel; calculate a phase error based on the phase estimate and the loop gain; correct the frequency offset using the phase error; and communicate with the base station after correcting the frequency offset.

Channel estimator 101, based on the received signal received through a radio channel, estimates an estimated value of a channel showing channel characteristics of the radio channel. Correlation value calculator 103 calculates a time domain channel correlation value showing the time correlation of the radio channel, based on the estimated value of the channel. Channel power calculator 102 calculates channel power as the power of the received signal, based on the estimated value of the channel. Noise power calculator 104 calculates noise power as the power of the noise component contained in the received signal. Corrector 105 corrects the channel power based on the noise power and corrects the time domain channel correlation value based on the corrected channel power and the noise power. Fading Doppler frequency estimator 200 estimates the fading Doppler frequency based on the corrected time domain channel correlation value.

Channel estimator 101, based on the received signal received through a radio channel, estimates an estimated value of a channel showing channel characteristics of the radio channel. Correlation value calculator 103 calculates a time domain channel correlation value showing the time correlation of the radio channel, based on the estimated value of the channel. Channel power calculator 102 calculates channel power as the power of the received signal, based on the estimated value of the channel. Noise power calculator 104 calculates noise power as the power of the noise component contained in the received signal. Corrector 105 corrects the channel power based on the noise power and corrects the time domain channel correlation value based on the corrected channel power and the noise power. Fading Doppler frequency estimator 200 estimates the fading Doppler frequency based on the corrected time domain channel correlation value.

Provided is a method for forming a Wi-Fi Peer-to-Peer (P2P) group using Wi-Fi Direct. The method includes acquiring device information of other P2P device corresponding to a connection target by P2P devices that will form a Wi-Fi P2P group; checking a type of the other P2P devices based on the acquired device information; adjusting an intent value of a P2P device depending on the checked type of the other P2P devices; and forming a Wi-Fi P2P group based on the adjusted intent values of the P2P devices.