A communication system includes a repetitive orthogonal frequency-division multiplexing (ROFDM)transmitter communicating with an ROFDM receiver. The ROFDM transmitter includes an ROFDM modulator, which includes a K-point Fast Fourier Transform receiving a block of time-domain data symbols and generating an initial orthogonal frequency-division multiplexing symbol. The initial orthogonal frequency-division multiplexing symbol is based on a block of frequency-domain data symbols corresponding to the block of time-domain data symbols. The initial orthogonal frequency-division multiplexing symbol includes an ending part. The ROFDM modulator includes an orthogonal frequency-division multiplexing symbol repeater generating a repetitive orthogonal frequency-division multiplexing symbol by repeatedly reproducing the initial orthogonal frequency-division multiplexing symbol. The modulator includes a cyclic prefix adder pretending a cyclic prefix to the repetitive orthogonal frequency-division multiplexing symbol to generate a baseband transmitted signal. The cyclic prefix includes the ending part of the initial orthogonal frequency-division multiplexing symbol. The ROFDM receiver includes an ROFDM demodulator.

Apparatuses, computer readable media, and methods for physical layer short feedback. An apparatus of a high efficiency (HE) station is disclosed. The apparatus comprising circuitry configured to: decode a trigger frame for short feedback, the trigger frame comprising an indication of a resource unit (RU) to respond to a short feedback request, where the RU comprises one or more tones and one or more symbols. The circuitry may be further configured to encode a short feedback response to the short feedback request on the RU, where each of the one or more tones of the RU is to be encoded with one or more of: a positive signal, a negative signal, and no signal. The circuitry may be further configured to configure the HE station to transmit the short feedback response to an access point in accordance with orthogonal frequency division multiple access (OFDMA) using resources of the RU.

Embodiments of this application provide a signal sending method, including: determining a first subcarrier, wherein an offset is between the first subcarrier and a center subcarrier of target resource blocks in a target bandwidth, and the offset is related to a subcarrier spacing; and determining a signal, wherein a location of the first subcarrier is the same as a carrier frequency location of the signal.

A method for managing beam squint in a phased antenna array system operating at millimeter wavelengths using carrier aggregation includes determining a minimum array gain threshold, determining an upper bound for a fractional bandwidth for a fixed number of antennas, and constructing a codebook with a predetermined coverage range based on at least one of an angle of arrival or an angle of departure and further based on the upper bound. The method further includes performing carrier aggregation for the fixed number of antennas and selecting at least two antennas based on the codebook.

Technologies to improve band edge channel performance for radios are described. One device includes a baseband processor with an Orthogonal Frequency Division Multiplexing (OFDM) physical layer (PHY) parameter structure. The OFDM PHY layer parameter structure includes first parameter information that controls operation of an OFDM PHY in a first mode. The baseband processor establishes a wireless communication link with a second device and transmits first data to the second device in the first mode using a transmit power level. The baseband processor determines that the device is connected with the second device on a band edge channel that is adjacent to a restricted frequency band. The baseband processor modifies the first parameter information to second parameter information, the second parameter information controls operation of the OFDM PHY in a second mode. The baseband processor transmits transmit second data to the second device in the second mode using the transmit power level.

A power headroom transmission method and a device are provided. The transmission method is applied to a terminal device that supports use of two different types of waveform for data transmission, the terminal sends a first power headroom information and .sub.M, wherein the first power headroom information is used to indicate power headroom of the terminal device when data is transmitted by using the first waveform, .sub.M is a difference between a first maximum power and a second maximum power of the terminal device, the first maximum is a maximum power when using the first waveform, the second maximum is a maximum power when using the second waveform.

A receiver circuit for separating a plurality of layers multiplexed in an orthogonal frequency domain multiplexed (OFDM) signal includes: a descrambling sub-circuit configured to descramble a plurality of signals received on non-adjacent subcarriers of the OFDM signal to generate a plurality of descrambled signals; an inverse fast Fourier transform sub-circuit configured to transform the descrambled signals from a frequency domain to a received signal including a plurality of samples in a time domain; and a layer separation sub-circuit configured to separate the layers multiplexed in the received signal by: defining a first time domain sampling window and a second time domain sampling window in accordance with a size of the inverse fast Fourier transform; extracting one or more first layers from the samples in the first time domain sampling window; and extracting one or more second layers from the samples in the second time domain sampling window.

Methods, systems, and devices are described for hierarchical communications and low latency support within a wireless communications system. An eNB and/or a UE may be configured to operate within the wireless communications system which is at least partially defined through a first layer with first layer transmissions having a first subframe type and a second layer with second layer transmissions having a second subframe type. The first subframe type may have a first round trip time (RTT) between transmission and acknowledgment of receipt of the transmission, and the second layer may have a second RTT that is less than the first RTT. Subframes of the first subframe type may be multiplexed with subframes of the second subframe type, such as through time division multiplexing. In some examples symbols of different duration may be multiplexed such that they different symbol durations coexist.

A communication system includes a repetitive orthogonal frequency-division multiplexing (ROFDM) transmitter communicating with an ROFDM receiver. The ROFDM transmitter includes an ROFDM modulator, which includes a K-point Fast Fourier Transform receiving a block of time-domain data symbols and generating an initial orthogonal frequency-division multiplexing symbol. The initial orthogonal frequency-division multiplexing symbol is based on a block of frequency-domain data symbols corresponding to the block of time-domain data symbols. The initial orthogonal frequency-division multiplexing symbol includes an ending part. The ROFDM modulator includes an orthogonal frequency-division multiplexing symbol repeater generating a repetitive orthogonal frequency-division multiplexing symbol by repeatedly reproducing the initial orthogonal frequency-division multiplexing symbol. The modulator includes a cyclic prefix adder prepending a cyclic prefix to the repetitive orthogonal frequency-division multiplexing symbol to generate a baseband transmitted signal. The cyclic prefix includes the ending part of the initial orthogonal frequency-division multiplexing symbol. The ROFDM receiver includes an ROFDM demodulator.

A method and device for dynamically allocating resources to a frequency band of a short transmission time interval (TTI) in a wireless communication system is provided. Specifically, a plurality of first downlink channels and a second downlink channel included in a subframe corresponding to one TTI are received, wherein the plurality of first downlink channels are received during sTTIs and the second downlink channel is received during the TTI. The plurality of first downlink channels are sequentially received. The plurality of first downlink channels are demodulated using control information included in a downlink control information (DCI) used for the second downlink channel and an RRC message. The control information and RRC message indicate frequency resources for the plurality of first downlink channels.