A method for equalizing a wireless communication channel includes transmitting a data signal over a primary channel. During transmission of the data signal, a corresponding data signal is sent over a secondary channel. The information received from the secondary channel is compared to the information received from the primary channel and differences between the information received from each of the channels are observed. These differences are used as inputs to an equalizer algorithm that may be used to reduce distortion of the data signal sent over the primary channel.

A communication system uses skywave propagation to transmit data between communication nodes over a data transmission path. An atmospheric sensor is configured to collect atmospheric data at the reflection point of the data transmission path where the transmission path is redirected from the atmosphere toward the surface of the Earth. Data collected by the atmospheric sensor may be used to predict future ionospheric conditions and determine optimum working frequencies for transmission of data between the communication nodes.

A communication system uses skywave propagation to transmit data between communication nodes over a data transmission path. An atmospheric sensor is configured to collect atmospheric data at the reflection point of the data transmission path where the transmission path is redirected from the atmosphere toward the surface of the Earth. Data collected by the atmospheric sensor may be used to predict future ionospheric conditions and determine optimum working frequencies for transmission of data between the communication nodes.

The objective of the embodiments of the present disclosure is to provide a method, device and system for backscatter communication based on Wi-Fi signals. Wherein, a Wi-Fi signal reader device broadcasts periodically a device query message to instruct backscatter communication devices upon receiving the device query message to report their respective device ID information; said backscatter communication devices report their device ID information to said Wi-Fi signal reader device in response to said device query message; said Wi-Fi signal reader device counts the number of the backscatter communication devices that have reported their respective device ID information, and allocates to them the corresponding time slot information.

The objective of the embodiments of the present disclosure is to provide a method, device and system for backscatter communication based on Wi-Fi signals. Wherein, a Wi-Fi signal reader device broadcasts periodically a device query message to instruct backscatter communication devices upon receiving the device query message to report their respective device ID information; said backscatter communication devices report their device ID information to said Wi-Fi signal reader device in response to said device query message; said Wi-Fi signal reader device counts the number of the backscatter communication devices that have reported their respective device ID information, and allocates to them the corresponding time slot information.

The present disclosure relates to a skywave large-scale MIMO communication method, model, and system. A skywave communication base station in a short waveband is constructed using a large-scale antenna array, wherein skywave large-scale MIMO communication is carried out between the skywave communication base station and a user terminal in a coverage area by ionospheric reflection. The skywave communication base station determines a spacing of the large-scale antenna array according to a maximum operating frequency, and communicates with the user terminal based on a TDD communication mode, wherein a skywave large-scale MIMO signal is transmitted based on an OFDM modulation mode or a power efficiency improvement modulation mode. The skywave communication base station selects a communication carrier frequency within a short waveband range according to a real-time ionospheric channel characteristic, and adaptively selects an OFDM modulation parameter and a signal frame structure.

The present disclosure relates to a skywave large-scale MIMO communication method, model, and system. A skywave communication base station in a short waveband is constructed using a large-scale antenna array, wherein skywave large-scale MIMO communication is carried out between the skywave communication base station and a user terminal in a coverage area by ionospheric reflection. The skywave communication base station determines a spacing of the large-scale antenna array according to a maximum operating frequency, and communicates with the user terminal based on a TDD communication mode, wherein a skywave large-scale MIMO signal is transmitted based on an OFDM modulation mode or a power efficiency improvement modulation mode. The skywave communication base station selects a communication carrier frequency within a short waveband range according to a real-time ionospheric channel characteristic, and adaptively selects an OFDM modulation parameter and a signal frame structure.

A communication system uses multiple communications links, preferably links that use different communications media. The multiple communications links may include a high latency/high bandwidth link using a fiber-optic cable configured to carry large volumes of data but having a high latency. The communications links may also include a low latency/low bandwidth link implemented using skywave propagation of radio waves and configured to carry smaller volumes of triggering data with a lower latency across a substantial portion of the earth's surface. The triggering data may be sent in a data stream as data frames without headers, security information, or error checking codes. The two communications links may be used together to coordinate various activities such as the buying and selling of financial instruments.

A method for equalizing a wireless communication channel includes transmitting a data signal over a primary channel. During transmission of the data signal, a corresponding data signal is sent over a secondary channel. The information received from the secondary channel is compared to the information received from the primary channel and differences between the information received from each of the channels are observed. These differences are used as inputs to an equalizer algorithm that may be used to reduce distortion of the data signal sent over the primary channel.

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.