Abstract: The present disclosure discloses a method and user equipment for sending a preamble sequence. The method includes determining a transmit power for sending a preamble sequence, and sending the preamble sequence according to the determined transmit power.

Abstract: Embodiments of this application disclose a data transmission method that includes sending, by a base station, first scheduling information to first UE. The first scheduling information instructs the first UE to send data to second UE based on the first scheduling information. The method includes receiving, by the base station, first feedback information sent by the first UE. The method includes sending, by the base station, second scheduling information to the first UE if the first feedback information indicates that the second UE fails to receive the data. Embodiments of this application further provide a base station, UE, and a data transmission system. In embodiments of this application, the first UE may perceive a data receiving status of the second UE by receiving the first feedback information, so that a corresponding resource can be assigned again for data retransmission.

Abstract: Embodiments of the present invention provide a device and a method for data transmission in D2D communication. The method includes: transmitting, by transmitting user equipment UE, scheduling signaling to receiving UE, where the scheduling signaling includes frequency domain resource information, a quantity of cycles that can be occupied, or transmission pattern information; and transmitting, by the transmitting UE, user data to the receiving UE according to the scheduling signaling, so that the receiving UE receives the user data according to the scheduling signaling. In the technical solution of the present invention, if there is no feedback from the receiving UE in a D2D communication process, the transmitting UE may repeatedly transmit the user data, and the receiving UE may repeatedly receive the user data, thereby improving reliability of data transmission.

Abstract: Embodiments provide a data exchange method, a terminal device, and a network device. In accordance with the disclosure, a terminal device can obtain resource information for communicating with another terminal device. The resource information can indicate a time-frequency resource and an antenna port corresponding to an antenna polarization direction. The terminal device can then send scheduling information and data information to the another terminal device using the time-frequency resource and the antenna polarization direction. Time-frequency resources and/or antenna polarization directions used by any two terminal devices to send scheduling information and data information to other terminal devices can be different. In this way, terminal devices using different transmit antenna ports can use a same time-frequency resource, and an optional dimension of resource information is increased, thereby increasing an overall system communication capacity.

Abstract: A communication method, a network side device, and a terminal are provided. In the method, a network side device selects one group of values from at least two preset groups of values for a transmission parameter set. The network side device sends the selected group of values. A terminal sends communication data based on the group of values of the at least two groups of values of the transmission parameter set.

Abstract: A method includes: mapping, by a first terminal device, first information to a first time unit and a second time unit; and sending, by the first terminal device, the first information in the first time unit and the second time unit, where the first time unit includes a first symbol including a first cyclic prefix, the second time unit includes at least one second symbol including a second cyclic prefix, a length of the first cyclic prefix is greater than a length of the second cyclic prefix, and a length of the first time unit is equal to N times a length of the second symbol including the second cyclic prefix in the second time unit.

Abstract: A data sending method, a terminal device, an access network device, and a system are provided. The method includes: obtaining, by a terminal device, a sending period of first data; obtaining, by the terminal device, configuration information of a first resource; determining, a second resource based on the configuration information of the first resource and a sending period of the first data; and selecting, by the terminal device, a resource other than the second resource to send the first data. When selecting a resource used for V2X communications data or D2D communications data, the terminal device excludes the second resource that cannot be used for the V2X communications data or the D2D communications data, so as to avoid a conflict between the second resource and the resource selected by the terminal device for sending the first data, and improve reliability and security of D2D communication and V2X communication.

Abstract: A power control method and a terminal device are disclosed. The method includes: sending, by a first terminal device, first data and first sidelink control information corresponding to the first data to at least one second terminal device; receiving, by the first terminal device, at least one piece of power adjustment information from the at least one second terminal device, where the at least one piece of power adjustment information is determined by the at least one second terminal device based on at least one of the first data and the first sidelink control information; determining, by the first terminal device, a transmit power for second data based on the at least one piece of power adjustment information; and sending, by the first terminal device, the second data to the at least one second terminal device at the transmit power.

Abstract: The present application discloses a method and device for processing multimedia information, an electronic equipment, and a computer-readable storage medium. The method for processing multimedia information includes: detecting whether multimedia configuration parameters have changed during a process of recording multimedia information; and recording the multimedia information based on the changed multimedia configuration parameters when detecting that the multimedia configuration parameters have changed. According to the embodiments of the present application, multimedia configuration parameters of the special effects such as stickers, make-up, filters, and mixing can be added during the recording of multimedia information, which improves the user experience.

Abstract: A communication method, a network side device, and a terminal are provided. In the method, a network side device selects one group of values from at least two preset groups of values for a transmission parameter set; the network side device sends the selected group of values; and a terminal sends communication data based on the group of values of the at least two groups of values of the transmission parameter set. The present invention can adapt to different system statuses and service requirements, thereby improving transmission performance.

Abstract: The present invention discloses a D2D synchronization method, user equipment, and a serving cell. The method includes: acquiring, by user equipment, synchronization control information of a serving cell; acquiring an identity of a first synchronization signal sent by a first synchronization source that is obtained through searching on a second transmission carrier frequency, and signal quality of the first synchronization source; determining, according to the identity of the first synchronization signal, the signal quality of the first synchronization source, and the synchronization control information, whether to start to send a synchronization signal; sending, by the user equipment, a second synchronization signal on a third transmission carrier frequency whose frequency is different from a frequency of a carrier frequency of the serving cell, so that a problem of synchronization between different user equipments in a multi-carrier frequency transmission scenario can be resolved.

Abstract: The present disclosure relates to communication methods and communications apparatus. In one example communication method, a first terminal determines a start time unit of a resource period, and transmits communication data in the resource period, where communication data is transmitted in the start time unit and the communication data is retransmitted in another time unit of the resource period. Then the first terminal sends transmission sequence number indication information and time domain transmission resource indication information to a second terminal that performs direct communication with the first terminal.

Abstract: A synchronization method includes: determining a data signal, where a target sequence in the data signal is mapped to at least one symbol that includes the first symbol within a time unit, data in the data signal is mapped to at least one another symbol in the time unit other than the at least one symbol, the first symbol includes a cyclic prefix, and the target sequence is used by a second device to synchronize the data signal; and sending the data signal to the second device in the time unit. In the present disclosure, a sequence used to synchronize a data signal for each transmission is mapped at an equal spacing to at least one symbol that includes the first symbol within a time unit for the current transmission.

Abstract: This application provides a communication method and a terminal device. The communication method may include determining, by user equipment (UE), a candidate resource set on a first carrier, where the first carrier is a carrier on which a resource is currently to be selected, and the first carrier is used to transmit first data.

Abstract: Embodiments provide user equipment includes a processor and a transmitter. The processor determines a time domain resource within a T2 time length based on second time domain resource indication information, where the second time domain resource indication information indicates a time domain resource occupied for data transmission within a T1 time length, and T2 is twice of T1. The processor further generates second control information, where the second control information includes the second time domain resource indication information. The transmitter sends the second control information. The transmitter further sends data on the time domain resource that is determined within the T2 time length. In this way, only a time domain pattern with a half time length of a period is defined, so that total time domain patterns in a system are applicable to a vehicle-to-vehicle communication scenario. In addition, time domain resource indication information occupies fewer bits, thereby saving system resources.

Abstract: A communication method and a communications apparatus are disclosed. In the communication method, a first terminal obtains a resource period parameter, where the resource period parameter is sent by a network-side device or preconfigured by the first terminal. The resource period parameter includes a period duration of each of at least one resource. The first terminal determines a start time unit of a resource period, and the first terminal sends communication data according to the start time unit of the resource period and the resource period parameter.

Abstract: This application provides a synchronization method and an apparatus. The method includes: mapping, by first UE, to-be-transmitted data and a first sequence to a symbol of a first time unit, to obtain a first signal, where the first sequence is mapped to at least one symbol at a non-starting location of the first time unit; and sending, by the first UE, the first signal to second UE. The second UE receives the first signal, obtains the first sequence, and performs synchronization on the first signal based on the first sequence.

Abstract: The present disclosure provides a data sending method. A first terminal device, determines at least two carriers to transmit at least two pieces of data corresponding to a same transport block, and in a one-to-one correspondence with the at least two pieces of data. The at least two pieces of data can be sent by the first terminal to a second terminal device or a network device by using the at least two carriers. When the first terminal device sends data, the first terminal device may send the at least two pieces of data to the second terminal device or the network device on the at least two carriers to improve reliability of data transmission. The at least two pieces of data may be sent simultaneously, to avoid an increased latency by transmissions of the at least two pieces of data in different time units.

Abstract: A power control method and a terminal device are disclosed. The method includes: sending, by a first terminal device, first data and first sidelink control information corresponding to the first data to at least one second terminal device; receiving, by the first terminal device, at least one piece of power adjustment information from the at least one second terminal device, where the at least one piece of power adjustment information is determined by the at least one second terminal device based on at least one of the first data and the first sidelink control information; determining, by the first terminal device, a transmit power for second data based on the at least one piece of power adjustment information; and sending, by the first terminal device, the second data to the at least one second terminal device at the transmit power.

Abstract: A method and system for including a base station that configures a first user equipment (UE) that is in a radio resource control connected state with the base station. The UE is configured to be a synchronization source and transmit a first device-to-device synchronization signal (D2DSS) by using a synchronization resource that comprises a time resource, a frequency resource or a time and frequency resource. The base station instructs the first UE to transmit the first D2DSS using the synchronization resource. The base station signals the UE to configure the UE separately from the signal to transmit the D2DSS, and both of the signals are performed with radio resource control signaling from the base station to the UE.