Embodiments of the present disclosure relate to methods, devices and computer readable media for communication on unlicensed band. In example embodiments, a method includes determining, at a terminal device, a time interval preceding a start symbol for uplink transmission. The method further includes determining, based on a first signal generating operation for the start symbol, a second signal generating operation for the time interval. The method further includes transmitting, to a network device over the time interval, a signal generated based on the second signal generating operation.

A terminal including a reception unit that receives configuration information in a high frequency band higher than or equal to a frequency band of a frequency range 2 (FR2), the FR2 being in a range including a frequency range 1 (FR1) that is a low frequency band and the FR2 that is a high frequency band in a new radio (NR) system; and a control unit that configures at least one of a format of a random access preamble, a sequence of the random access preamble, a subcarrier spacing applied to a channel on which the random access preamble is to be transmitted, or a subcarrier spacing applied to an uplink shared channel, based on the configuration information.

A method is provided for estimating at least one characteristic of a signal received by a receiver, the signal having been transmitted in succession by a plurality of antennas in successive time segments, each segment being dedicated to one separate antenna, the signal being modulated into the form of pulses according to ultra-wideband modulation. The method includes steps of: receiving and digitizing the signal, computing the product of multiplication of each symbol of the received signal by the complex conjugate of the corresponding transmitted symbol, for each segment and for each symbol of the signal received for this segment, estimating a phase error by means of a phase-locked loop applied to the product, for each segment, determining a reference phase by means of a linear regression applied to the phase errors estimated for all of the segments, determining, for at least one pair of antennas, a phase difference between the signals transmitted by the antennas of the pair, on the basis of the difference between the reference phases computed for the segments associated with the antennas.

Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a user equipment (UE) may receive an indication of parameters for estimating tone reservation (TR) subcarriers, based at least in part on energies of data symbols of a communication, having tone reservation applied for the communication. The UE may receive the communication having the tone reservation applied to the TR subcarriers. Numerous other aspects are described.

Methods, systems, and devices for dynamic rate matching patterns for spectrum sharing are described. In some examples, a user equipment (UE) may measure one or more interference levels associated with resources of a physical resource block (e.g., interference levels associated with respective subcarriers or other division in the frequency domain, with respective symbol durations or other division in the time domain, or a combination thereof), and determine a rate matching pattern based on the interference level measurements. In some examples, the rate matching pattern may include a pattern of resources for communications between the UE and a base station (e.g., for downlink communications). The UE may transmit an indication of the rate matching pattern to the base station, and the base station may schedule or transmit one or more subsequent downlink transmissions based at least in part on the indication of the rate matching pattern received from the UE.

Methods, systems, and devices for wireless communications are described. A device may receive an indication of a subcarrier spacing (SCS) for communications in a plurality of transmission time intervals (TTIs), where a TTI include a set of symbols, a corresponding set of cyclic prefixes, and a padding duration. The device may receive a control signal indicating a configuration for the padding duration, at least a portion of which may be reallocated as one or more additional symbols with corresponding one or more additional cyclic prefixes. In some examples, the one or more additional cyclic prefixes and at least a first portion of the set of cyclic prefixes may be reduced in duration in comparison with a remaining portion of the set of cyclic prefixes. The device may communicate during the padding duration using the one or more additional symbols and the corresponding one or more additional cyclic prefixes.

A network entity and a resource arrangement method are provided. In the method, a resource use condition of a radio resource is obtained. The radio resource is configured with multiple subcarriers. A subcarrier spacing between the subcarriers is adjusted according to the resource use condition.

A method of transmitting data by a transmitter to a receiver in a wireless communications network. The method comprises receiving data for transmission to the receiver via a communications channel, dividing the data into portions for transmission, receiving, for each of the portions of data, an indication of channel information from the receiver for use by the transmitter in determining values for one or more communications parameters with which the portion of data should be transmitted, determining the values for the one or more communications parameters based on the received channel information, dynamically generating, for each of the portions of data, a waveform representative of the portion of data, and transmitting each of the portions of data, using the generated waveform representations and in accordance with the values of the one or more communications parameters, to the receiver.

Some demonstrative embodiments include apparatuses, devices, systems and methods of communicating a PPDU including a training field. For example, an Enhanced Directional Multi-Gigabit (DMG) (EDMG) wireless communication station may be configured to determine one or more Orthogonal Frequency Division Multiplexing (OFDM) Training (TRN) sequences in a frequency domain based on a count of one or more 2.16 Gigahertz (GHz) channels in a channel bandwidth for transmission of an EDMG PPDU including a TRN field; generate one or more OFDM TRN waveforms in a time domain based on the one or more OFDM TRN sequences, respectively, and based on an OFDM TRN mapping matrix, which is based on a count of the one or more transmit chains; and transmit an OFDM mode transmission of the EDMG PPDU over the channel bandwidth, the OFDM mode transmission comprising transmission of the TRN field based on the one or more OFDM TRN waveforms.

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.