A transmitting method includes: configuring a frame using a plurality of orthogonal frequency-division multiplexing (OFDM) symbols, by allocating time resources and frequency resources to a plurality of transmission data; and transmitting the frame, wherein the frame includes a first period in which a preamble which includes information on a frame configuration of the frame is transmitted, and a second period in which the plurality of transmission data are transmitted by at least one of time division and frequency division, and among the plurality of OFDM symbols, OFDM symbols included in the second period include pilot symbols arranged along a time axis with a predetermined spacing therebetween, and a predetermined number of data symbols.

A transmitting method includes: configuring a frame using a plurality of orthogonal frequency-division multiplexing (OFDM) symbols, by allocating time resources and frequency resources to a plurality of transmission data; and transmitting the frame, wherein the frame includes a first period in which a preamble which includes information on a frame configuration of the frame is transmitted, and a second period in which the plurality of transmission data are transmitted by at least one of time division and frequency division, and among the plurality of OFDM symbols, OFDM symbols included in the second period include pilot symbols arranged along a time axis with a predetermined spacing therebetween, and a predetermined number of data symbols.

Provided are a frame configuring unit configured to configure a frame using a plurality of orthogonal frequency-division multiplexing (OFDM) symbols, by allocating time resources and frequency resources to a plurality of transmission data, and a transmitter which transmits the frame. The frame includes a first period in which a preamble which includes information on a frame configuration of the frame is transmitted, a second period in which a plurality of transmission data are transmitted by time division, a third period in which a plurality of transmission data are transmitted by frequency division, and a fourth period in which a plurality of transmission data are transmitted by time division and frequency division.

Provided are a frame configuring unit configured to configure a frame using a plurality of orthogonal frequency-division multiplexing (OFDM) symbols, by allocating time resources and frequency resources to a plurality of transmission data, and a transmitter which transmits the frame. The frame includes a first period in which a preamble which includes information on a frame configuration of the frame is transmitted, a second period in which a plurality of transmission data are transmitted by time division, a third period in which a plurality of transmission data are transmitted by frequency division, and a fourth period in which a plurality of transmission data are transmitted by time division and frequency division.

A method of operating a first node to generate a secret key for encrypting wireless transmissions between the first node and a second node. The method comprises receiving a first training signal comprising a plurality of subcarriers from the second node and constructing a matrix from the frequency responses of each of the plurality of subcarriers of the first training signal at the first node. A singular value decomposition of the matrix is computed; and a secret key is derived from one or more singular vectors of the singular value decomposition.

A method of operating a first node to generate a secret key for encrypting wireless transmissions between the first node and a second node. The method comprises receiving a first training signal comprising a plurality of subcarriers from the second node and constructing a matrix from the frequency responses of each of the plurality of subcarriers of the first training signal at the first node. A singular value decomposition of the matrix is computed; and a secret key is derived from one or more singular vectors of the singular value decomposition.

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 wireless communication device transmits data to multiple wireless terminals at the same timing. The wireless communication device includes a complement calculation part configured to calculate the amount of complement for transmission data for each wireless terminal among multiple wireless terminals on multiple subcarriers distributed and assigned thereto, a complementation part configured to complement transmission data using the amount of complement calculated for each wireless terminal, and a transmitter configured to transmit the complemented transmission data to multiple wireless terminals via multiple subcarriers. The wireless communication device further includes a frame generator configured to generate frames (e.g. OFDMA frames) used to multiplex and transmit the complemented transmission data to multiple wireless terminals. The complement calculation part calculates the amount of complement based on the number of available subcarriers, which is determined via carrier sensing.

A wireless communication device transmits data to multiple wireless terminals at the same timing. The wireless communication device includes a complement calculation part configured to calculate the amount of complement for transmission data for each wireless terminal among multiple wireless terminals on multiple subcarriers distributed and assigned thereto, a complementation part configured to complement transmission data using the amount of complement calculated for each wireless terminal, and a transmitter configured to transmit the complemented transmission data to multiple wireless terminals via multiple subcarriers. The wireless communication device further includes a frame generator configured to generate frames (e.g. OFDMA frames) used to multiplex and transmit the complemented transmission data to multiple wireless terminals. The complement calculation part calculates the amount of complement based on the number of available subcarriers, which is determined via carrier sensing.

A method for beamformed transmission towards groups of terminal devices. Each terminal device is, according to a bandwidth part (BWP) configuration, configured with a BWP set. One BWP in the BWP set is an active BWP for the terminal device. The method is performed by a network node. The method comprises configuring a new terminal device entering one of the groups with an active BWP based on frequency overlap avoidance with the active BWPs of the terminal devices already part of the group entered. The method comprises serving all terminal devices by performing beamformed transmission towards the terminal devices in accordance with the active BWPs.