Demodulation of 5G and 6G messages involves complex demodulation reference signals that occupy valuable resource grid area. Disclosed are numerous configurations of short-form demodulation reference types that provide sufficient modulation information to enable a receiver to determine all of the predetermined modulation levels of the modulation scheme, while consuming minimal resources. Selection of the appropriate modulation scheme and demodulation reference type generally depends on many competing factors. Therefore, an AI model may be required. The AI model may be trained on network data to recommend when a different modulation scheme would be beneficial, as the network default or to serve a particular user device. The AI model may be configured to select between the disclosed short-form demodulation references and prior-art demodulation reference signals, thereby optimizing the subsequent network performance as well as individual user satisfaction, while minimizing costs, bandwidth, power, and especially avoiding interference with neighboring cells.

The present disclosure relates to a method for a terminal device to determine demodulation reference signal (DMRS), comprising: obtaining (211) a DMRS configuration and a corresponding signature assigned by a network side node; constructing (212) a DMRS according to the DMRS configuration; mapping (213) the DMRS to a physical channel assigned to the terminal device. The signature indicates a processing configuration for the physical channel. In the embodiments of the present disclosure, the signature, and DMRS configuration may be configured correspondingly, to obtain low-crosstalk DMRS signals for different terminal devices, thus, the number of the supported terminal devices may be improved.

The present disclosure relates to a pre-5.sup.th-Generation (5G) or 5G communication system to be provided for supporting higher data rates Beyond 4.sup.th-Generation (4G) communication system such as Long Term Evolution (LTE). A method for operating a terminal in a wireless communication system, the method comprises determining a time-frequency structure of a downlink reference signal, and receiving, from a base station, the downlink reference signal according to the time-frequency structure.

A reference signaling scheme is provided that is based on the use of a Zadoff Chu sequence with cyclic repetition, optionally code division multiplexing precoding, together with frequency domain spectral shaping (FDSS). A specific pulse shape design for the FDSS part of the reference signal scheme in some embodiments involves the use of a raised cosine pulse raised to the power of β. The new solution for generating reference signals has a Low peak average power ratio that matches the PAPR of SC-OQAM, good channel estimation performance, and the ability to implement CDM in the frequency domain to increase multiplexing gain.

Methods, systems, and devices for wireless communication are described. A user equipment (UE) may receive control signaling indicating a preamble configuration. The UE may receive a preamble in a time domain. The preamble may include a set of modulated bits during a first portion of an initial symbol duration of a slot. The set of modulated bits may include one or more of a first subset of network temporary identifier bits or a second subset of modulation and coding scheme (MCS) bits. The UE may process the preamble during a second portion of the initial symbol duration of the slot based on the preamble configuration.

A terminal according to one aspect of the present disclosure includes a control section that assumes that, in a case where time domain orthogonal cover code (TD-OCC) is configured for consecutive symbols of a sounding reference signal (SRS), the same sequence is configured to the consecutive symbols of the SRS, and a transmitting and/or receiving section that performs at least one of transmission processing and reception processing of the SRS, based on the TD-OCC. According to one aspect of the present disclosure, reduction in SRS capacity can be suppressed.

An transmission apparatus of the present disclosure comprises a transmission signal generator which, in operation, 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 unit (RU) allocation information and a user-specific field that carries per-user allocation information for 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, in operation, transmits the generated transmission signal.

A method and apparatus for generation of orthogonal training signals for transmission in an antenna array are described. In this embodiment, a set of P training signals is generated. The generation of the P training signals includes generating a first set of Zadoff-Chu sequences, where the first set of sequences is based on a first reference Zadoff-Chu sequence and first subsequent Zadoff-Chu sequences, where each one of the first subsequent Zadoff-Chu sequences is a cyclic shift of the first reference Zadoff-Chu sequence. A second set of sequences is generated based on a second reference sequence and second subsequent sequences that are cyclic shift of the second reference sequence. The P training signals are determined based on the first set of sequences and the second set of sequences. The training signals are then transmitted through a plurality of transmit paths of a base station towards a wireless network.

Methods, systems, and devices for wireless communication are described. A wireless device may identify an uplink/downlink (UL/DL) configuration that defines subframe configuration options for each subframe of a frame. For example, the UL/DL configuration may establish parameters for time division duplexing (TDD) operation between a base station and a user equipment (UE). The wireless device (e.g., the UE or base station) may determine a constraint for a subframe of the frame based on the UL/DL configuration and then determine an adaptive subframe configuration based on the constraint. The adaptive subframe configuration may include one or several downlink symbol periods and one or several uplink symbol periods. The wireless device may then communicate during the subframe according to the adaptive subframe configuration rather than the original UL/DL configuration; and, because the adaptive subframe may be constrained by the identified UL/DL configuration, the communication during the subframe may avoid disruption to UEs.

Provided is a radio communication device which can make Acknowledgement (ACK) reception quality and Negative Acknowledgement (NACK) reception quality to be equal to each other. The device includes: a scrambling unit (214) which multiplies a response signal after modulated, by a scrambling code “1” or “e.sup.−j(π/2)”, so as to rotate a constellation for each of response signals on a cyclic shift axis; a spread unit (215) which performs a primary spread of the response signal by using a Zero Auto Correlation (ZAC) sequence set by a control unit (209); and a spread unit (218) which performs a secondary spread of the response signal after subjected to the primary spread, by using a block-wise spread code sequence set by the control unit (209).