The present disclosure provides a method and an apparatus for random access in a wireless communication system, as well as a user terminal. The method includes: receiving indication information transmitted from a radio base station, the indication information instructing a user terminal to initiate a random access; determining a target Physical Random Access Channel (PRACH) resource from available resources based on a current coverage level and resource information carried in the indication information, the target PRACH resource being used for transmitting a PRACH signal for initiating the random access; and re-determining, in response to a failure to initiate the random access over the target PRACH resource, the target PRACH resource from the available resources based on an updated coverage level and the resource information, and transmitting the PRACH signal over the re-determined target PRACH resource. The present disclosure can solve the technical problem in the related art associated with low success rate of random accesses initiated by radio base stations.

This disclosure provides systems, methods and apparatus for asynchronous channel access control of a wireless system. In some aspects, a device may adjust the priority of one or more PPDUs and may perform other operations to ensure control of a wireless medium at certain times while still allowing for other devices to communicate on the wireless medium. For example, the device may adjust a backoff counter or one or more EDCA parameters to ensure obtaining control of the wireless medium to transmit a first PPDU of an application file. For one or more subsequent PPDUs of the application file, the device may again adjust a backoff counter or one or more EDCA parameters to allow other devices to obtain control of the wireless medium in certain scenarios (such as a second device to provide information back to the device or to otherwise transmit using the shared wireless medium).

Disclosed are a method, an apparatus, and a system for transmitting a signal using multiple carriers. In detail, provided are a wireless communication apparatus including a communication module; and a processor, wherein the processor obtains a common back-off counter for a carrier set on which data is to be transmitted, wherein the carrier set includes at least one component carrier, performs back-off of each of the component carriers using the obtained common back-off counter, and simultaneously transmits data through at least one component carrier in which the back-off is completed and a wireless communication method using the same.

A micro-power wireless access method and apparatus for the Internet of things for power transmission and transformation equipment involves a time synchronization process, a traffic channel access process, a control channel configuration information access process, and a control channel burst information access process. In the time synchronization process, an aggregation node determines a delay parameter and other parameters based on a timeslot in which traffic information randomly transmitted by a sensing terminal is located, and the sensing terminal adjusts transmission time of a corresponding frame based on the parameters. The traffic channel access process adopts a mode in which one-way reporting is mainly used, to minimize working time of a sensor. The present disclosure realizes limited two-way communication on a control channel, supports configuration of a sensor cycle, a threshold, and other parameters, and supports a retransmission mechanism on the control channel for important alarm information.

Methods, systems, and devices for wireless communications are described. The described techniques provide for a user equipment (UE) to adjust a random access message that is transmitted to a base station in an asynchronous uplink transmission. The UE may use a constrained mapping of time and frequency resources for the random access message or transmit all portions of the message in a continuous transmission. The UE may also adjust the timing of the portions of the message. The base station may use a portion of the message, such as a preamble, to perform channel estimation for another portion of the message, such as a payload, to improve decoding of the transmitted message. Additionally, the UE may configure a waveform of the message to improve the continuous transmission of the message, for example by reducing interference between portions of the message.

A wireless communication system utilizes a synchronization signal block (SSB) structure to enable beam switching at higher sub carrier spacing (SCS) or uplink transmissions within an SSB. The SSB structure has a first SCS for an SSB transmission and a second SCS for a data transmission. The SSB structure is based on the first SCS and the second SCS, with the SSB structure including at least one gap between SSB symbols or between SSBs. The wireless communication system transmits or receives an SSB based on the SSB structure. A base station may transmit a downlink signal during the gap, for example, where the second SCS is much greater than the first SCS. A user equipment may transmit an uplink signal such as an acknowledgment during the at least one gap. The user equipment or the base station may perform analog beam switching during the at least one gap between SSBs.

In a communications system which complies with LTE including a base station which transmits data by using an OFDM (Orthogonal Frequency Division Multiplexing) method as a downlink access method, and a mobile terminal, in a case in which an uplink scheduling request signal is transmitted by using an S-RACH when an Ack/Nack signal is being transmitted by using an Ack/Nack exclusive channel, the transmission of the Ack/Nack signal is stopped while the uplink scheduling request signal is transmitted.

A method, a terminal, and a base station for asynchronous uplink transmission are provided, to reduce an uplink data transmission latency and signaling overheads when a terminal and a base station are in out-of-synchronization state. The method includes: obtaining asynchronous transmission parameter information that is the same as that of a base station, where asynchronous transmission parameter information includes physical resource information, modulation and coding scheme information, and physical resource frame format information, and the physical resource frame format information includes length information of a physical resource frame; determining a length of an asynchronous transmission frame according to the physical resource frame format information; and sending first uplink information to the base station according to the asynchronous transmission parameter information by using the asynchronous transmission frame.

This disclosure provides an uplink signal transmission method and user equipment and relates to the field of communications technologies. The uplink signal transmission method includes: selecting, by the user equipment, a CP from a preset cyclic prefix CP candidate set to send an uplink transmission signal, where the CP candidate set includes at least two types of CPs of different lengths.

Provided are a method for communicating in a wireless communication system and a device using the same. A wireless device receives a switching command instructing the switching between a clear channel assessment (CCA) operation and a non-CCA operation in an unlicensed band. According to the switching command, the wireless device performs the CCA operation or the non-CCA operation in the unlicensed band.