One example includes a troposcatter communication terminal. The terminal includes an antenna comprising a plurality of communication ports that extend from a rear side of the antenna to a front side of the antenna. The terminal also includes a positioner mechanically coupled to the antenna and being configured to mechanically control positioning of the antenna. The terminal further includes an electronics package mechanically coupled to the rear side of the antenna. The electronics package includes a troposcatter radio communicatively coupled to the antenna via the plurality of communications ports to transmit and receive troposcatter communication signals via the plurality of communication ports at the front side of the antenna.

One example includes a troposcatter communication terminal. The terminal includes an antenna comprising a plurality of communication ports that extend from a rear side of the antenna to a front side of the antenna. The terminal also includes a positioner mechanically coupled to the antenna and being configured to mechanically control positioning of the antenna. The terminal further includes an electronics package mechanically coupled to the rear side of the antenna. The electronics package includes a troposcatter radio communicatively coupled to the antenna via the plurality of communications ports to transmit and receive troposcatter communication signals via the plurality of communication ports at the front side of the antenna.

A method and communication system has been developed to increase the number of messages sent over a bandwidth limited channel and/or under noisy conditions by using a variable message length encoding and decoding scheme. With this technique, the messages having a higher probability of being sent are shorter as compared to the messages that are less likely to be sent under the current conditions. With this technique, a higher number of transactions per unit of time can be communicated and/or executed over a given bandwidth limited channel. When the transmitted message is received, the receiver does not know the message length, but the receiver deduces the length by using information from various error detection and correction techniques, such as forward error correction (FEC) and cyclic redundancy check (CRC) techniques.

A method and communication system has been developed to increase the number of messages sent over a bandwidth limited channel and/or under noisy conditions by using a variable message length encoding and decoding scheme. With this technique, the messages having a higher probability of being sent are shorter as compared to the messages that are less likely to be sent under the current conditions. With this technique, a higher number of transactions per unit of time can be communicated and/or executed over a given bandwidth limited channel. When the transmitted message is received, the receiver does not know the message length, but the receiver deduces the length by using information from various error detection and correction techniques, such as forward error correction (FEC) and cyclic redundancy check (CRC) techniques.

A communication system transmits data signals between communication nodes. A first data signal is transmitted as an electromagnetic wave along a first data transmission path to a receiver using skywave propagation. A second data signal, identical to the first data signal, is transmitted to the receiver along a second data transmission path. The two data signals are compared at the receiver to determine any distortion caused by the skywave propagation. Data regarding the distortion is sent back to the transmitter so that subsequent transmitted data signals may be preconditioned when sent by skywave propagation.

A communication system transmits data signals between communication nodes. A first data signal is transmitted as an electromagnetic wave along a first data transmission path to a receiver using skywave propagation. A second data signal, identical to the first data signal, is transmitted to the receiver along a second data transmission path. The two data signals are compared at the receiver to determine any distortion caused by the skywave propagation. Data regarding the distortion is sent back to the transmitter so that subsequent transmitted data signals may be preconditioned when sent by skywave propagation.

A signal transmission method and apparatus, a terminal device, a smart device, and an electronic device, are provided. The signal transmission method includes: sending, by a terminal device, a first signal to a smart device having a backscatter function, and receiving a second signal reflected by the smart device; and performing, by the terminal device when the smart device stops reflecting the second signal, channel estimation on an interference channel.

A wireless communication system includes a first wireless communication node for transmitting a data signal that is sent to a second wireless communication node by skywave propagation over at least two different data transmission paths. The first data transmission path includes at least one reflection point where the data signal is reflected by the atmosphere and the second data transmission path includes more reflection points than the first data transmission path. The data signal that travelled along the first data transmission path is decoded before the data signal that travelled along the second data transmission path.

A wireless communication system includes a first wireless communication node for transmitting a data signal that is sent to a second wireless communication node by skywave propagation over at least two different data transmission paths. The first data transmission path includes at least one reflection point where the data signal is reflected by the atmosphere and the second data transmission path includes more reflection points than the first data transmission path. The data signal that travelled along the first data transmission path is decoded before the data signal that travelled along the second data transmission path.

Various embodiments herein relate to methods and systems for backscatter communication using pre-defined templates. In accordance with at least one embodiment, there is provided a backscattering communication system, comprising a transmitting unit, a backscattering tag, and a receiving unit. The transmitting unit is configured to transmit a signal comprising a transmitted frame including a pre-defined data payload. The backscattering tag is configured to: receive, from the transmitting unit, the signal comprising the transmitted frame; encode tag data over the pre-defined data payload to generate a modified data payload; and transmit a backscattered signal comprising a backscattered frame including the modified data payload. The receiving unit is configured to: receive, from the backscattering tag, the backscattered signal; and decode the modified data payload, in the backscattered frame, to recover the tag data, wherein the decoding is based on prior knowledge of the receiving unit of the pre-defined data payload.