A satellite transmitter includes K transmission antenna elements, a multiplexing unit configured to multiplex each of K digital signals on a frequency axis and then convert the multiplexed digital signals to time-domain digital signals, a digital-to-analog converter, a PAPR calculation unit configured to calculate a PAPR for each of the K digital signals, a beam-to-beam relative phase calculation unit configured to calculate a beam-to-beam relative phase for suppressing a peak power of the transmission antenna elements, an excitation coefficient calculation unit configured to calculate K updated excitation coefficients based on the beam-to-beam relative phase and the beam-formation excitation coefficient, and an excitation coefficient multiplication unit configured to generate the digital signals of a frequency domain to be output to the multiplexing unit by multiplying a received relay signal by each of the K updated excitation coefficients in the frequency domain.

Aspects of the present disclosure describe a system and method for synchronizing time, frequency, and phase among a plurality of devices.

Wireless communication systems and methods are provided that include at least one base transmitter unit, at least one repeater unit, at least one receiver, and an artificial intelligence unit. The base transmitter unit is configured to transmit a data signal. The repeater unit is in communication with the transmitter and is configured to transmit the data signal via sky wave propagation. The receiver is in communication with the transmitter and the repeater and is configured to receive the data signal. The artificial intelligence unit monitors ionospheric conditions in the area and controls the data signal, making adjustments so the data signal overcomes skip zones. The adjustments may include automatically adjusting the power and position of the antenna array to re-route the data signal and/or dynamically changing the frequency of the data signal.

Wireless communication systems and methods are provided that include at least one base transmitter unit, at least one repeater unit, at least one receiver, and an artificial intelligence unit. The base transmitter unit is configured to transmit a data signal. The repeater unit is in communication with the transmitter and is configured to transmit the data signal via sky wave propagation. The receiver is in communication with the transmitter and the repeater and is configured to receive the data signal. The artificial intelligence unit monitors ionospheric conditions in the area and controls the data signal, making adjustments so the data signal overcomes skip zones. The adjustments may include automatically adjusting the power and position of the antenna array to re-route the data signal and/or dynamically changing the frequency of the data signal.

A communication system that can control smart repeaters includes: a base station that is applied to a fifth-generation wireless access system; and a smart repeater having a beamforming function and performing relay processing between the base station and a communication terminal or between a communication terminal connected to the base station and another communication terminal. The base station transmits information related to a beam used in the relay processing to the smart repeater, and the smart repeater forms a beam based on the information related to the beam received from the base station and performs the relay processing.

A communication system that can control smart repeaters includes: a base station that is applied to a fifth-generation wireless access system; and a smart repeater having a beamforming function and performing relay processing between the base station and a communication terminal or between a communication terminal connected to the base station and another communication terminal. The base station transmits information related to a beam used in the relay processing to the smart repeater, and the smart repeater forms a beam based on the information related to the beam received from the base station and performs the relay processing.

Certain aspects of the present disclosure relate to methods and apparatus for data transmission in synchronization slots. A method for use by a base station for data transmission in synchronization slots includes transmitting a synchronization signal (SS) burst, wherein different SS blocks of the burst are transmitted using different transmit beams and performing frequency division multiplexing (FDM) or time division multiplexing (TDM) to include one or more other types of signals that need to be multicast and are also transmitted using the different transmit beams.

Certain aspects of the present disclosure relate to methods and apparatus for data transmission in synchronization slots. A method for use by a base station for data transmission in synchronization slots includes transmitting a synchronization signal (SS) burst, wherein different SS blocks of the burst are transmitted using different transmit beams and performing frequency division multiplexing (FDM) or time division multiplexing (TDM) to include one or more other types of signals that need to be multicast and are also transmitted using the different transmit beams.

A satellite transmitter includes K transmission antenna elements, a multiplexing unit configured to multiplex each of K digital signals on a frequency axis and then convert the multiplexed digital signals to time-domain digital signals, a digital-to-analog converter, a PAPR calculation unit configured to calculate a PAPR for each of the K digital signals, a beam-to-beam relative phase calculation unit configured to calculate a beam-to-beam relative phase for suppressing a peak power of the transmission antenna elements, an excitation coefficient calculation unit configured to calculate K updated excitation coefficients based on the beam-to-beam relative phase and the beam-formation excitation coefficient, and an excitation coefficient multiplication unit configured to generate the digital signals of a frequency domain to be output to the multiplexing unit by multiplying a received relay signal by each of the K updated excitation coefficients in the frequency domain.

In a wireless communication system that includes a base station, a plurality of relay stations that are moving, and a plurality of terminal stations in a service area, and performs downlink multiple access from the base station to each of the plurality of terminal stations via one or more relay stations of the plurality of relay stations, the base station includes a downlink multiple access unit configured to identify a relay station of the plurality of relay stations transmitting a signal receivable in the service area based on positions of the plurality of relay stations, frequency multiplex-transmit a data signal in a different frequency band to each of the plurality of terminal stations via the relay station, and spatial multiplex-transmit a data signal to a terminal station of the plurality of terminal stations supporting spatial multiplex transmission in a particular frequency band and via the plurality of relay stations.