Wireless communications systems and methods related to communicating control information are provided. A method of wireless communication performed by a user equipment (UE) may include performing a clear channel assessment (CCA), transmitting, to a first UE based on the CCA being successful, a first transport block (TB) via a first sub-PSSCH associated with a first sub-slot, and transmitting, to at least one of the first UE or a second UE, a second TB via a PSSCH associated with a slot.

For example, a wireless communication device may be configured to determine an energy state of a 2.16 Gigahertz (GHz) channel bandwidth (BW) in a millimeterWave (mmWave) wireless communication frequency band according to an energy detection mechanism; and, based on the energy state of the 2.16 GHz channel BW, to select between allowing or disabling the wireless communication device to transmit an mmWave Physical layer (PHY) Protocol Data Unit (PPDU) over an mmWave wireless communication channel, which at least partially overlaps the 2.16 GHz channel BW and is different from the 2.16 GHz channel BW, the mmWave wireless communication channel having an mmWave channel BW of at least 80 Megahertz (MHz).

A Channel Access Indicator (CAI) may be employed in New Radio Unlicensed (NR-U) to indicate channel occupation by a node to nodes outside its cell, indicate channel occupation by a node to nodes within its cell to aid spectral reuse, and to trigger a handshake between nodes within a cell to ensure that receiver has clear channel to transmit and receive.

A user equipment (UE) and a method of performing transmission in a shared spectrum by the same are provided. The method includes initiating a channel occupancy (CO) and sharing the CO to at least a second UE. This can solve issues in the prior art and provide a method that the CO initiated by the UE can be shared with other one or more UEs, so that the one or more UEs can have higher probability to access a channel, leading to a low latency communication.

Certain aspects of the present disclosure provide techniques for sidelink communications in an unlicensed spectrum. A method that may be performed by a user equipment (UE) and a base station (BS) includes sensing, prior to a start of a time window, a frequency band to determine whether the frequency band is idle, the time window divided in time into a plurality of time periods, the frequency band divided in time across multiple of the plurality of time periods into a corresponding plurality of resources comprising one or more unassigned resources and one or more assigned resources assigned to one or more other wireless communication devices for wireless communication.

Embodiments of this disclosure include a channel access method in a wireless local area network (WLAN) and related apparatus. In the method, a communication device receives a first overlapping basic service set (OBSS) frame on a primary channel, determines a first channel with a busy channel state based on bandwidth information carried in the first OBSS frame, and performs channel contention when switching from the primary channel to a second channel. After the communication device backs off to 0 on the second channel, the communication device determines a third channel used for transmitting data, where the third channel does not include any sub-channel of the first channel, and the first channel includes the primary channel.

Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a first user equipment (UE) may transmit, to a second UE, an initial transmission of a transport block via a sidelink unlicensed band. The UE may receive, from the second UE, a negative acknowledgement (NACK) based at least in part on the initial transmission of the transport block. The UE may transmit, to the second UE and based at least in part on the NACK and a retransmission reservation, a retransmission of the transport block via the sidelink unlicensed band in a retransmission occasion of a plurality of retransmission occasions associated with the retransmission reservation. Numerous other aspects are described.

Provided is a radio communication device which can separate propagation paths of antenna ports and improve a channel estimation accuracy even when using virtual antennas. The device includes: a mapping unit which maps a data signal after modulation to a virtual antenna and a virtual antenna; a phase inversion unit which inverts the phase of S0 transmitted from an antenna port in synchronization with a phase inversion unit between the odd-number slot and the even-number slot; the phase inversion unit which inverts the phase of R0 transmitted from the antenna port; a phase inversion unit which inverts the phase of S1 transmitted from an antenna port in synchronization with a phase inversion unit; and the phase inversion unit which inverts the phase of R1 transmitted from an antenna port.

A communication device determines whether a PHY data unit is to be transmitted in a first frequency band from among multiple frequency bands in which a WLAN communication protocol permits operation. The multiple frequency bands also include a second frequency band. The communication device determines whether the PHY data unit is to include a PS-Poll frame, and whether a BSS color is currently disabled for the WLAN. In response to i) determining that the PHY data unit is to be transmitted in the first frequency band, ii) determining that the PHY data unit is not to include a PS-Poll frame, and iii) determining that the BSS color is not currently disabled for the WLAN: the communication device determines that a TXOP duration subfield in a PHY preamble of the PHY data unit cannot be set to a value defined by the WLAN communication protocol for indicating a TXOP duration that is unspecified.

The present disclosure relates to a communication method and system for converging a 5.sup.th-Generation (5G) communication system for supporting higher data rates beyond a 4.sup.th-Generation (4G) system with a technology for Internet of Things (IoT). The present disclosure may be applied to intelligent services based on the 5G communication technology and the IoT-related technology, such as smart home, smart building, smart city, smart car, connected car, health care, digital education, smart retail, security and safety services.

Disclosed are a base station and a random access preamble sequence detection method thereof, and a terminal and a random access channel configuration method thereof.