The present disclosure discloses a method and a system for transmitting DFT-s-OFDM symbols. A data sequence for transmitting as an OFDM symbol is received as input from a data source. A reference sequence for transmitting along with the data sequence as the OFDM symbol is generated and time-multiplexed with the data sequence, to generate a multiplexed sequence. Thereafter, a Discrete Fourier Transform (DFT) operation is performed on the multiplexed sequence to generate a DFT-spread-Orthogonal Frequency Division Multiplexing (DFT-s-OFDM) symbol that is further processed for transmitting over a channel. The transmission of the reference sequence and the data sequence in a single OFDM symbol provides better bandwidth utilization and flexibility in modulation of the reference sequence and the data sequence.

A signal multiplexing apparatus and method using layered division multiplexing are disclosed. A signal multiplexing apparatus according to an embodiment of the present invention includes a combiner configured to generate a multiplexed signal by combining a core layer signal and an enhanced layer signal at different power levels; a power normalizer configured to reduce the power of the multiplexed signal to a power level corresponding to the core layer signal; a time interleaver configured to generate a time-interleaved signal by performing interleaving that is applied to both the core layer signal and the enhanced layer signal; and a frame builder configured to generate a broadcast signal frame using the time-interleaved signal and L1 signaling information.

Various aspects described herein relate to techniques for using orthogonal demodulation reference signals (DMRSs) for downlink control channels in wireless communications systems. In an aspect, a method for a user equipment (UE) includes receiving one or more DMRSs over a multi-symbol downlink control channel. The method may further include identifying a time-first control channel element (CCE)-to-resource element group (REG) mapping for the multi-symbol downlink control channel, and identifying an orthogonal DMRS of the one or more DMRSs based on the time-first CCE-to-REG mapping, and decoding the multi-symbol downlink control channel based on at least the identified orthogonal DMRS.

The present technology relates to a signal processing apparatus, a signal processing method, and a program capable of reducing the number of pins for transmitting and receiving data. The signal processing apparatus is provided with a signal transmission unit configured to perform classification for a signal to be transmitted and received between processing units that process an obtained signal, perform time division multiplexing for the signal classified into a group, and transmit the signal. The classification is performed depending on at least one feature of an update period, an update timing, and a tolerable transmission delay of the signal. Further, the signal belonging to the group is subjected to time division multiplexing in such a manner that the transmission is completed within the update period, the transmission is completed within a range of the tolerable delay, and the transmission is performed with a minimum number of pins. The present technology can be applied to a reception apparatus that receives and processes airwaves.

An apparatus and method for generating a broadcast signal frame including preamble for signaling injection level information. An apparatus for generating broadcast signal frame according to an embodiment of the present invention includes an injection level controller configured to generate a power reduced enhanced layer signal by reducing a power of an enhanced layer signal; a combiner configured to generate a multiplexed signal by combining a core layer signal and the power reduced enhanced layer signal; a power normalizer configured to reduce the power of the multiplexed signal to a power level corresponding to the core layer signal; a time interleaver configured to generate a time-interleaved signal by performing interleaving that is applied to both the core layer signal and the enhanced layer signal; and a frame builder configured to generate a broadcast signal frame including a preamble for signaling injection level information corresponding to the injection level controller.

A wireless communication method includes sending, by a first device in a wireless network, a poll packet (32, 38, 44) for polling a second device in the wireless network. The poll packet includes an address of the second device. The second device receives and at least partially decodes the poll packet. The second device sends a response packet (36, 40, 46) in response to the poll packet. The sending of at least part of the response packet is substantially simultaneous with the receiving of at least part of the poll packet by the second device. Wireless communication systems, transmitters and receivers using the method are also described.

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 different symbol durations coexist.

Methods, systems, and devices for wireless communications are described that support frequency and time domain multiplexing for low peak-to-average waveforms with multiple streams. A user equipment (UE) may identify sets of symbols associated with different streams (e.g., multiple single-carrier discrete Fourier transform (DFT)-spread waveforms), where each stream may be associated with a low peak-to-average power ratio (PAPR). In some cases, different waveforms may be mapped to subsets of frequency resources through frequency division multiplexing (FDM). The UE may further reduce the PAPR of the multiplexed waveforms by performing time division multiplexing (TDM) across the single-carrier streams, and sets of symbols that are not used by one waveform may be used by another waveform. Frequency domain phase ramps may be applied to align the multiplexed waveforms. Signals included in an uplink transmission according to these techniques may maintain properties similar to single-carrier waveforms, including a low PAPR.

Disclosed are a TRS receiving method comprising: receiving, from a base station, information indicating that a TRS is transmitted in a subframe; receiving the TRS transmitted in the subframe; and performing tracking by using the TRS, and a terminal performing, in the subframe to which the TRS is transmitted, the demodulation of data or not transmitting an acknowledgement/negative ACK (ACK/NACK) for the data.

An apparatus and method for broadcast signal frame using layered division multiplexing are disclosed. An apparatus for generating broadcast signal frame according to an embodiment of the present invention includes a combiner configured to generate a multiplexed signal by combining a core layer signal and an enhanced layer signal at different power levels; a power normalizer configured to reduce the power of the multiplexed signal to a power level corresponding to the core layer signal; a time interleaver configured to generate a time-interleaved signal by performing interleaving that is applied to both the core layer signal and the enhanced layer signal; and a frame builder configured to generate a broadcast signal frame including a preamble for signaling, start position information of Physical Layer Pipes (PLPs) and time interleaver information shared by the core layer signal and the enhanced layer signal.