Abstract: Systems, methods, and instrumentalities are disclosed for separating a channel and data without the use of reference signals. For example, a wireless transmit/receive unit (WTRU) may determine a first orthogonal frequency-division multiplexing (OFDM) symbol based on a data vector. The WTRU may determine a second OFDM symbol by applying a circular time-inverse operation and a conjugate operation to the first OFDM symbol. The WTRU may send the first OFDM symbol and the second OFDM symbol. The first and the second OFDM symbols may be sent to consecutively. Discrete Fourier Transform (DFT)-spread and nonlinear preprocessing (exponential transformation at the transmitter) may be used and/or peak-to-average power ratio (PAPR) may be reduced via randomizer block at the receiver.

Abstract: A method for increasing the efficiency and robustness of non-orthogonal multiple access (NOMA) schemes may include storing relationships that associate codewords with values of bit sets, receiving information bits and converting the information bits into bit sets, determining codewords associated with the bit sets, and transmitting the determined codewords. A first codeword may be pre-defined for a WTRU. A second codeword associated with a first bit set may be determined using a first relationship between the first codeword and a value of the first bit set. A third codeword associated with a second bit set may be determined using a second relationship between the second codeword and a value of the second bit set.

Abstract: A method for transmitting a discrete fourier transform (DFT) DFT-S-OFDM signal including frequency domain reference symbols is disclosed. The method comprises: determining to null a plurality of data symbols prior to DFT-spreading; performing DFT-spreading including the determined null data symbols; puncturing an interleaved output of the DFT-spreading; inserting reference symbols in a frequency domain of the punctured and interleaved DFT-S-OFDM signal; and transmitting the DFT-S-OFDM signal with inserted reference symbols to a receiver. The transmitted DFT-S-OFDM signal enables the receiver to apply zeros corresponding to the reference symbols to an interleaved input of DFT-despreading, and cancel interference due to the puncturing by using all outputs of the DFT-despreading.

Abstract: Methods and systems for operation in a wireless network are provided, the methods including receiving modulated data symbols and zeros in a frequency-domain, and mapping in the frequency-domain the modulated data symbols and zeros in an interleaved manner to sub-carriers within a resource allocation. The methods and systems further include generating a time-domain data signal based on the mapped sub-carriers, and generating a time domain cancellation signal by sign inverting and repeating a predetermined number of time-domain samples at a tail portion of the data signal. The methods and systems further include combining the time-domain data signal and the time domain cancellation signal to generate an exact zero tail data signal such that the exact zero tail data signal has a zero tail length equal to the predetermined number of time-domain samples, and transmitting the exact zero tail data signal.

Abstract: Methods, apparatus and systems are disclosed. One representative method implemented by a wireless transmit/receive unit includes determining a first beamforming matrix; sending, to a network entity, an indication of the first beamforming matrix; and receiving, from the network entity, an indication of a second beamforming matrix determined by the network entity from at least the first beamforming matrix for beamforming data for transmission.

Abstract: Methods, apparatuses and systems are provided for grant-less (GL) uplink transmissions. A wireless transmit/receive unit (WTRU) may receive a configuration of a set of GL Physical Uplink Shared Channel (GL-PUSCH) frequency resources. The WTRU may monitor for a downlink control information (DCI) message, wherein the DCI message includes an indication of a presence of at least a subset of the set of GL-PUSCH frequency resources. If the WTRU successfully receives the DCI message, the WTRU may select one or more GL-PUSCH frequency resources from the subset of the set of GL-PUSCH frequency resources and may select a time period. The WTRU may transmit data on a GL-PUSCH using the selected GL-PUSCH frequency resources during the selected time period. The WTRU may also monitor for hybrid automatic repeat request acknowledgement (HARQ-ACK) based on the selected GL-PUSCH frequency resources. The WTRU may monitor for the DCI during a fixed time window.

Abstract: Systems, methods, and instrumentalities are disclosed for physical (PHY) layer multiplexing of different types of traffic in 5G systems. A device may receive a communication. The communication may include a first traffic type. The device may monitor the communication for an indication that the communication includes a second traffic type that is multiplexed with and/or punctures the first traffic type. An indicator received in the communication and detected by the monitoring may indicate where the second traffic type is located in the communication. The first traffic type and the second traffic type may be multiplexed at a resource element (RE) level. For example, a first traffic type may be punctured by a second traffic type at the RE level. The device may de code one or more of the first or second traffic types in the communication based on the indication.

Abstract: Systems, methods and instrumentalities are disclosed for superposed signaling for bandwidth efficiency in wireless communications. Homogeneous and heterogeneous signals may be superposed on the same channel. Superposed signals may comprise, for example, multi carrier, frequency division and code division signals, including multiple access, e.g., OFDMA and CDMA, signals. Data for various receivers may be dynamically selected for signal superpositioning, for example, based on radio access technology, communication rate (e.g. high and low rates), distance between transmitter and receiver (e.g. near and far signals). Communication rate and power may be allocated to superposed signals. Interference nulling may be applied, for example, by selecting or excluding spreading codes and/or subcarriers. Nulled locations may be used to transmit critical information. Interference shaping may be applied to modify interference, e.g., by transmitting interference symbols using reserved spreading codes. Support information, e.

Abstract: A wireless transmit/receive unit (WTRU), using mixed numerologies, may, in a first codeword, map a first set of bits to a higher order modulation scheme and a second set of bits to a lower order scheme, and transmit the first codeword. The WTRU may determine that data of the first codeword is to be re-transmitted on a second codeword, containing the same number of bits as the first codeword. In the second codeword, the WTRU may map a first set of bits to the lower order scheme and a second set of bits to the higher order scheme. The first set of bits of the second codeword may contain the same number of bits as the second set of bits of the first codeword and may contain at least a subset of data in the first set of bits of the first codeword. The WTRU may transmit the second codeword.

Abstract: Methods and systems for operation in a wireless network are provided, the method including receiving modulated data symbols and zeros in a frequency-domain, and mapping in the frequency-domain the modulated data symbols and zeros in an interleaved manner to sub-carriers within a resource allocation. The method further includes generating a time-domain data signal based on the mapped sub-carriers, and generating a time domain cancellation signal by sign inverting and repeating a predetermined number of time-domain samples at a tail portion of the data signal. The method further includes combining the time-domain data signal and the time domain cancellation signal to generate an exact zero tail data signal such that the exact zero tail data signal has a zero tail length equal to the predetermined number of time-domain samples, and transmitting the exact zero tail data signal.

Abstract: A method for reporting power headroom is disclosed. Power headroom may be reported across all carriers (wideband), for a specific carrier, or for a carrier group. The formula used to calculate the power headroom depends on whether the carrier (or a carrier in the carrier group) has a valid uplink grant. If the carrier or carrier group does not have a valid uplink grant, the power headroom may be calculated based on a reference grant. The power headroom is calculated by a wireless transmit/receive unit and is reported to an eNodeB.

Abstract: A wireless transmit receive unit (WTRU) may monitor downlink short transmission time intervals (sTTIs) for a sTTI physical downlink control channel (sPDCCH) region. The WTRU may determine the sPDCCH region from a set of candidate sPDCCH regions for an uplink grant. The sPDCCH may be determined based on a WTRU-specific parameter.

Abstract: Methods, devices, and systems for transmitting information using a unique word (UW) with discrete Fourier transform spread orthogonal frequency division multiplexing (DFT-s-OFDM) are described herein. In an example, a wireless transmit/receive unit (WTRU) may generate a reference sequence. Further, the WTRU may generate a DMRS sequence based on upsampling of the reference sequence. In an example, the DMRS sequence may include a plurality of repeating sequences. Further, in an example, each repeating sequence may include a head sequence, a reference sequences and a tail sequence. Also, a UW sequence within the DMRS may include one of the repeated head sequences and one of the repeated tail sequences. In addition, the WTRU may generate a DMRS signal based on a waveform operation on the DMRS sequence. The WTRU may then transmit the DMRS signal as a reference signal.

Abstract: A method and apparatus for a wireless transmit receive unit (WTRU) to use a contention-based uplink communications channel, applies a rule-based restriction of access to the contention-based uplink channel that attempts to use at least one contention-free uplink channel allocation for uplink transmissions on a condition that at least one contention-free uplink channel allocation has been granted.

Abstract: A method and apparatus are described for minimizing inter-cell interference at multiple wireless transmit/receive units (WTRUs) using a shared node (SN). Each WTRU may be configured to receive a desired signal transmitted by a base station in a cell combined with interfering signals transmitted by other base stations in other cells in a first transmission time interval (TTI), and a precoded signal transmitted by the SN in a second TTI. The WTRUs may buffer the desired and interfering mixed signals received in the first TTI, and then combine the buffered signals with the precoded signal received in the second TTI to minimize the interfering signal's power and maximize the desired signal's power at each WTRU so that the desired signal may be decoded with higher probability. The SN may generate the precoded signal based on codewords or codeword components transmitted by the base stations in the same resource blocks.

Abstract: Methods and systems for operation in a wireless network are provided, the method including receiving modulated data symbols and zeros in a frequency-domain, and mapping in the frequency-domain the modulated data symbols and zeros in an interleaved manner to sub-carriers within a resource allocation. The method further includes generating a time-domain data signal based on the mapped sub-carriers, and generating a time domain cancellation signal by sign inverting and repeating a predetermined number of time-domain samples at a tail portion of the data signal. The method further includes combining the time-domain data signal and the time domain cancellation signal to generate an exact zero tail data signal such that the exact zero tail data signal has a zero tail length equal to the predetermined number of time-domain samples, and transmitting the exact zero tail data signal.

Abstract: A base station may sense, on a cell using unlicensed spectrum, that the unlicensed spectrum is available for transmission. The base station may transmit, after sensing that the unlicensed spectrum is available, consecutive subframes. Each subframe may include a physical downlink control channel and a physical downlink shared channel.

Abstract: Systems, methods, and instrumentalities are disclosed for generating, transmitting, and/or receiving a hybrid spread waveform. The hybrid spread waveform may include a data portion and a hybrid guard interval (HGI) portion. The HGI portion may include a fixed prefix portion or a fixed suffix portion, and an adaptive low power tail (LPT) portion. The fixed prefix portion or the fixed suffix portion is a low power cyclic prefix (LPCP). The LPCP may be generated at least based on at least the channel delay spread and a power regrowth length. The adaptive LPT portion may be generated using a zero tail (ZT). The LPT is generated by inserting zeros at IFFT or DFT processing stage. A part of the adaptive LPT portion is used to carry data or control information. A waveform may be switched between a hybrid spread waveform and a fixed-CP waveform, e.g., via control signaling.

Abstract: A method and apparatus for operating supplementary cells in licensed exempt (LE) spectrum. An aggregating cell operating in a frequency division duplex (FDD) licensed spectrum is aggregated with a LE supplementary cell operating in a time sharing mode for uplink (UL) and downlink (DL) operations. The LE supplementary cell may be an FDD supplementary cell dynamically configurable between an UL only mode, a DL only mode, and a shared mode, to match requested UL and DL traffic ratios. The LE supplementary cell may be a time division duplex (TDD) supplementary cell. The TDD supplementary cell may be dynamically configurable between multiple TDD configurations. A coexistence capability for coordinating operations between the LE supplementary cell with other systems operating in the same channel is provided. Coexistence gaps are provided to measure primary/secondary user usage and permit other systems operating in the LE supplementary cell channel to access the channel.

Abstract: Techniques may be used to generate a multi-length Zero Tail (ZT) Discrete Fourier Transform-spread Orthogonal Frequency Domain Modulation (DFT-s-OFDM) signal for transmission. A selected allocation of frequency resources may include a plurality of subbands. Subbands may be assigned to wireless transmit/receive units (WTRUs) (i.e., users), and zero head length and zero tail length may be assigned to each of the assigned subbands according to a pattern to combat inter-symbol interference (ISI). The ZT DFT-s OFDM signal may generated for transmission over the assigned subbands in accordance with the assigned zero head length and the assigned zero tail length.