A resource mapping method and apparatus and a resource mapping indication method and apparatus are provided to adapt to an interference cancellation function of a receiver. According to the method, a network device obtains a mapping mode used for resource mapping during uplink transmission, and sends, to a terminal, information indicating the mapping mode. The mapping mode is used to indicate mapping locations of a plurality of modulation symbols in a resource mapping block (RMB), the RMB comprises a plurality of resource elements (REs), and at least one of the plurality of REs carries at least two modulation symbols.

A terminal is disclosed including a processor that determines, when retransmission of a side channel in a communication between a plurality of terminals is performed, a modulation order for the retransmission of the side channel by using a MCS table based on side control information; a transmitter that transmits the side channel based on the determined modulation order, and a receiver that receives downlink control information including at least a UL-SCH indicator field, wherein the processor, if retransmission of an uplink shared channel is performed, determines a time density of a phase tracking reference signal (PTRS) based on whether a modulation and coding scheme (MCS) index is larger than a certain value, and wherein the transmitter transmits the PTRS. In other aspects, a radio communication method, and a system are also disclosed.

Systems and methods for efficient signaling Hybrid Automatic Repeat Request Acknowledgement (HARQ-ACK) for an uplink data transmission are disclosed. In some embodiments, a method of signaling HARQ-ACK feedback for an uplink data transmission sent from a wireless device to a radio network node comprises obtaining HARQ-ACK feedback for the uplink data transmission, encoding the obtained HARQ-ACK feedback on to an unused bit combination of a field in a downlink control channel, and transmitting the downlink control channel to the wireless device. Embodiments of the present disclosure enable wireless device power saving using positive HARQ-ACK feedback without increasing the static downlink control signaling overhead and without reducing coverage for downlink control information.

Methods, systems, and devices for wireless communication are described that support communication of information buts based on reference signal index modulation (RS-IM). A base station and a UE may transmit a number of downlink and uplink information bits (e.g., downlink control bits, uplink control bits) using index modulation schemes applied on references signals. A base station and a UE may transmit reference signal transmissions using reference signal index modulation, in which a set of information bits may be encoded using one or more coding techniques, in conjunction with RS-IM techniques, to enhance reliability of some or all of the information bits. Error detection bits may be added to the information bits, and included when coding is performed. Coding may include channel coding, repetition of reference signals for combining at a receiving device, or any combinations thereof.

A reception device includes receivers and controller. Receivers receive a plurality of modulation signals modulated by a transmission device. Controller selects a communication scheme on the basis of phase difference between reception signals, which are the modulation signals received by the receivers, and of polarization plane deviation of the reception signals from transmission signals, which are the modulation signals transmitted from the transmission device, and sets, for the transmission device, a modulation scheme corresponding to the communication scheme.

Methods, systems, and devices for increasing the reliability of low latency transmissions are described. For example, multiple control messages and/or multiple data messages may be transmitted for a single transport block. Explicit and/or implicit signaling may be used to support the repetition of control and data transmissions in a low latency environment. For example, explicit signaling may be used to indicate a correspondence between repeated control and/or data messages. Additionally or alternatively, particular configurations may be used to implicitly signal a correspondence between repeated control and/or data messages.

A method for operating a user equipment (UE) is provided. The method comprises obtaining configuration information for one or more repetitions for one or more channels of a physical downlink control channel (PDCCH), a physical downlink shared channel (PDSCH), or a physical uplink shared channel (PUSCH), wherein the configuration information comprises a parameter to extend a maximum number of repetitions for the one or more channels; and transmitting or receiving the one or more repetitions according to the configuration information.

A transmission apparatus of the present disclosure comprises a transmission signal generator which generates a transmission signal that includes a legacy preamble, a non-legacy preamble and a data field, wherein the non-legacy preamble comprises a first signal field and a second signal field, the second signal field comprising a first channel field and a second channel field, each of the first channel field and the second channel field comprising a common field that carries resource assignment information for one or more terminal stations and a user-specific field that carries per-user allocation information for the one or more terminal stations, and wherein a part of the user-specific field of one of the first channel field and the second channel field whichever is longer than the other channel field in length before appending padding bits is relocated to the other channel field; and a transmitter which transmits the generated transmission signal.

Disclosed are an encoding ratio setting method and a radio communication device which can avoid encoding of control information at an encoding ratio lower than necessary and suppress lowering of the transmission efficiency of the control information. In the device, an encoding ratio setting unit (122) sets the encoding ratio R′.sub.control of the control information which is time-multiplexed with user data, according to the encoding ratio R.sub.data of the user data, ΔPUSCHoffset as the PUSCH offset of each control information, and ΔRANKoffset as the rank offset based on the rank value of the data channel using Expression (1).

A method for operating a communications controller includes defining a positive integer quantity of resource element groups from a resource block with a positive integer number N resource elements in each resource element group, the resource block having a total number of resource elements, the total number of resource elements consisting of available resource elements and reserved resource elements. The method also includes assigning a plurality of available resource elements to fill in each of the positive integer quantity of resource element groups with N available resource elements in each resource element group, and blocking any unassigned available resource elements from being used in a resource element group. The method further includes interleaving a plurality of control messages onto the positive integer quantity of resource element groups, and transmitting the positive integer quantity of resource element groups.