A transmitting apparatus is provided. The transmitting apparatus includes: a frame generator configured to generate a frame including a plurality of orthogonal frequency-division multiplexing (OFDM) symbols; and a guard interval (GI) inserter configured to insert GIs into the generated frame, wherein the plurality of OFDM symbols are divided into a bootstrap, a preamble, and a payload, and the GI inserter inserts first GIs having a size corresponding to a fast Fourier transform (FFT) size of each of OFDM symbols configuring the payload into front ends of each of the OFDM symbols, inserts second GIs having a size corresponding to a quotient obtained by dividing an extra region of the payload calculated based on the FFT size of the OFDM symbols configuring the payload, the number of OFDM symbols, and the size of the first GIs by the number of OFDM symbols into front ends of each of the first GIs, and inserts a cyclic postfix (CP) having a size corresponding to the remainder remaining after dividing the extra region of the payload by the number of OFDM symbols into a rear end of a final OFDM symbol configuring the payload.

A method includes storing multiple signals received from a user equipment (UE) in a queue. The method also includes estimating a sounding reference signal (SRS) signal-to-noise-ratio (SNR) and determining a filtered SNR based on the received signals. The method also includes computing one or more features based on the filtered SNR and at least some of the received signals in the queue. The method also includes determining (i) a channel condition of the UE and (ii) a speed range of the UE based on the one or more computed features, wherein the channel condition of the UE comprises line-of-sight (LoS) or non-line-of-sight (NLoS). The method also includes determining a transmission configuration based on the channel condition of the UE and the speed range of the UE.

A first wireless communication apparatus assigns a pilot signal without an effective signal component at least in an adjacent frequency component to a generated transmit signal, and transmits the transmit signal including the pilot signal. A second wireless communication apparatus converts the received signal or a frequency-converted signal obtained by frequency conversion of the signal into a signal in a frequency domain, sets an approximate value of the distance between the second wireless communication apparatus and the first wireless communication apparatus, calculates a coefficient γk, based on the approximate value of the distance, the effective bandwidth, the speed of light, the number of FFT points, and the frequency component number, extracts a signal in the frequency domain, generates a phase noise compensated sampling signal, and reproduces data transmitted by the first wireless communication apparatus.

Multiple channels are aggregated. In an example embodiment, first data is transmitted on a first channel to a wireless device, and second data is simultaneously transmitted on a second channel to the wireless device. The first data and the second data are transmitted in a coordinated manner by aggregating the first channel and the second channel. Various example channel characteristics and combinations thereof are described. Different data allocation options for aggregated channels are described. Other alternative implementations are also presented herein.

Methods, systems, and devices for wireless communications are described. A wireless device such as a user equipment (UE) may receive control signaling from a scheduling device such as a base station which indicates a configuration for decoding control channel information at the UE using a single discrete transform process. In such cases, the configuration may be for decoding control channel information such as downlink control information (DCI) that is time multiplexed with data channel information in one or more symbols of a single carrier waveform. Using the configuration, the UE may decode the control channel information and the data channel information using the discrete transform process.

Apparatus and methods for identifying a wireless signal-emitting device are disclosed. The apparatus is configured to sense and measure wireless communication signals from signal-emitting devices in a spectrum. The apparatus is operable to automatically detect a signal of interest from the wireless signal-emitting device and create a signal profile of the signal of interest; compare the signal profile with stored device signal profiles for identification of the wireless signal-emitting device; and calculate signal degradation data for the signal of interest based on information associated with the signal of interest in a static database including noise figure parameters of a wireless signal-emitting device outputting the signal of interest. The signal profile of the signal of interest, profile comparison result, and signal degradation data are stored in the apparatus.

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 low-computation underwater acoustic wake-up method based on a multi-carrier signal is provided. A multi-carrier signal corresponding to communication nodes is constructed, absolute values of the multi-carrier signal in a window at a receiver are summed for signal arrival detection, and then frequency points of the multi-carrier signal are detected many times by using the real fast Fourier transform to realize wake-up detection. The method is suitable for accurate wake-up at any distance within a maximum communication distance of two underwater acoustic nodes, has a small amount of calculation, and is suitable for low-power single-chip microcomputers. The modem can be in a low-power sleep state for a long time.

Methods, systems, and devices for wireless communications are described that may enable a user equipment (UE) or base station (e.g., a next-generation NodeB (gNB)) to identify that a waveform to be generated for a scheduled transmission is formed by one or more reference signal symbols and one or more data symbols. The waveform may be contained between a beginning boundary and an ending boundary with a duration equal to a total length of the one or more reference signal symbols and the one or more data symbols. The UE, base station, or both may generate the waveform by inserting a guard internal in the one or more reference signal symbols and the one or more data symbols to enable a receiver to perform a fast Fourier transform (FFT) for each of the one or more reference signal symbols and the one or more data symbols.

A receiver for detecting and recovering payload data from a received signal comprises a radio frequency demodulation circuit, a detector circuit and a demodulator circuit. The radio frequency demodulation circuit detects the received signal. The received signal carries the payload data as OFDM symbols in one or more of a plurality of time divided frames, each frame including a bootstrap signal, a preamble signal and a plurality of sub-frames. The demodulator circuit detects bootstrap OFDM symbols to identify communications parameters for detecting the fixed length signalling data, detects the fixed length signalling data to identify the communications parameters for detecting the variable length signalling data, detects the variable length signalling data, and uses the fixed and variable length signalling data to detect the payload data.