Abstract: A message transmission method and device relating to the field of communications technologies is disclosed, so as to improve an anti-interference capability in message transmission. The method includes: generating, by a base station, a scrambling code according to a first time parameter; then scrambling a system message according to the scrambling code; and finally sending the scrambled system message to a terminal on a physical broadcast channel. In this technical solution, because the first time parameter has different values at at least two different moments, scrambling codes determined at the at least two corresponding different moments are different. Therefore, a possibility at which the base station uses a same scrambling code to scramble a same system message repeatedly in a time period is reduced, so that an anti-interference capability in system message transmission is improved.

Abstract: Embodiments of this disclosure provide an indication information transmission method and an apparatus, and relate to the communications field. The method includes: generating, by a network device, indication information, where the indication information is used to indicate an existence status of a downlink control signal in a first time period; and sending, by the network device, the indication information to a terminal device.

Abstract: An information sending and receiving method and a device, the sending method including generating a first signal, and sending the first signal on a first resource. The first resource includes a first part of resource elements (REs), and the first part of the REs comprises at least one of a first RE element or a second RE element. The first RE element comprises all REs corresponding to an orthogonal frequency division multiplexing (OFDM) symbol 0, symbol 1, and symbol 2 in each of subframes 0, 5, and 9 of each radio frame on a first carrier, the second RE element comprises an REO, RE3, RE6, and RE9 in each of an OFDM symbol 4, 7, 8, and 11 in subframe 0 of each radio frame on the first carrier, and the first carrier is a carrier in a narrow band internet of things (NB-IoT) system.

Abstract: This application provides a system message indication method, an apparatus, and a system. The method may include generating, by a network device, notification information. The notification information may indicate status information of first information, the first information may include at least one bit in a first system message, and a quantity of bits included in the first information may be less than a quantity of bits included in the first system message. The method may also include sending, by the network device, the notification information to a terminal device.

Abstract: Embodiments of the present invention provide a multicast-based wireless communication method, a terminal device, and a base station. The method includes: in a process of receiving a current multicast service, receiving, by a terminal device, downlink control information DCI transmitted by a base station, where the DCI is used to schedule a current multicast traffic channel MTCH, and the DCI includes indication information used to indicate that configuration information of the MTCH is modified in a next modification period MP or a current MP; and obtaining, by the terminal device, modified configuration information according to the indication information. System flexibility is improved according to the embodiments of the present invention.

Abstract: A multicast service transmission method and a device, the method comprising determining, by a core network device, a coverage requirement of a to-be-transmitted multicast service, transmitting, by the core network device, the coverage requirement to an access network device, where the coverage requirement is used to determine a transmission parameter used to transmit the multicast service to a terminal device, receiving, by the access network device, the coverage requirement, determining, by the access network device according to the coverage requirement, the transmission parameter, and transmitting, by the access network device, the multicast service to the terminal device according to the transmission parameter.

Abstract: The Application discloses a signal sending method that includes: generating, by a network device, a first indication signal, where the first indication signal is used to indicate that a terminal device is not paged and/or no system message changes, the first indication signal corresponds to a first international mobile subscriber identity (IMSI) set, and a quantity of IMSIs in the first IMSI set is less than or equal to a quantity of IMSIs corresponding to one paging occasion (PO); and sending, by the network device, the first indication signal to a first terminal device, where the first terminal device is a terminal device corresponding to any IMSI in the first IMSI set.

Abstract: A time information transmission method and an apparatus are provided. A specific solution including: generating and sending first information whose indication granularity is less than or equal to 5 milliseconds, where the first information is used to indicate time information of a first reference point. The embodiments of this application are useable in a time synchronization process between the terminal device and the network device.

Abstract: The present disclosure relates to the field of wireless communications technologies, relates to a signal sending device, a signal receiving device, a symbol timing synchronization method, and a system, and resolves a problem that complexity of symbol timing synchronization performed by a terminal with relatively low crystal oscillator accuracy is high. In a receiving device, a receiving module receives a synchronization signal including a first signal and a second signal. The first signal includes N1 generalized ZC sequences, and the second signal includes N2 generalized ZC sequences. The second signal is used to distinguish different cells or different cell groups. There are at least two generalized ZC sequences with different root indexes in (N1+N2) generalized ZC sequences.

Abstract: The present disclosure discloses a method for transmitting downlink feedback information, a base station, and a terminal device, so as to ensure that the base station correctly receives the downlink feedback information sent by the terminal device, thereby effectively improving a transmission success rate of the downlink feedback information. In embodiments of the present disclosure, the method includes: sending, by the base station, indication information to the terminal device, where the indication information is used to indicate a target time-frequency resource location, the target time-frequency resource location is a time-frequency resource location at which the terminal device sends the downlink feedback information, and the downlink feedback information is used to feed back a reception status of downlink data that should be received by the terminal device; and receiving, by the base station, the downlink feedback information sent by the terminal device.

Abstract: A message transmission method and a device are used to accelerate a random access procedure. The method includes: receiving, by a terminal device, a repetition quantity of an uplink message from a network device, in response to determining that a reference signal receive power (RSRP) range of the terminal device is within an RSRP range corresponding to a signal coverage enhancement level 0, wherein the uplink message comprises a third message of a sequence of messages comprised in a random access attempt; calculating, by the terminal device, transmit power based on a power control parameter for the repetition quantity; and sending, by the terminal device, the uplink message to the network device based on the calculated transmit power.

Abstract: An indication signal configuration method and device are provided, and relate to the field of communications technologies. The method includes: sending, by a network device, first configuration information and second configuration information; sending a first indication signal on a first carrier; and sending a second indication signal on a second carrier, where the first configuration information is used to indicate duration of the first indication signal corresponding to the first carrier, the second configuration information is used to indicate duration of the second indication signal corresponding to the second carrier, the first terminal device is a terminal device that needs to receive the first indication signal, and the second terminal device is a terminal device that needs to receive the second indication signal.

Abstract: The present invention relates to the field of wireless communications technologies. In a receiving device, a receiving module receives a synchronization signal including a first signal and a second signal. The first signal includes N1 generalized ZC sequences, and the second signal includes N2 generalized ZC sequences. The second signal is used to distinguish different cells or different cell groups. There are at least two generalized ZC sequences with different root indexes in (N1+N2) generalized ZC sequences. A processing module performs a first sliding correlation operation and a second sliding correlation operation on the synchronization signal, and performs symbol timing synchronization according to a relationship between a sliding correlation peak generated when a sliding correlation is performed on the N1 generalized ZC sequences and a sliding correlation peak generated when a sliding correlation is performed on the N2 generalized ZC sequences.

Abstract: Embodiments of this application provide a random access preamble transmission method and an apparatus. The method includes: obtaining, by a terminal device, a scrambling code sequence, scrambling a random access preamble by using the scrambling code sequence, and sending a scrambled random access preamble to a network device. In this technical solution, the terminal device scrambles the random access preamble, and sends the scrambled random access preamble over a channel, to effectively eliminate inter-cell interference and resolve a possible target cell false alarm problem.

Abstract: The present disclosure discloses a method for transmitting downlink feedback information, a base station, and a terminal device, so as to ensure that the base station correctly receives the downlink feedback information sent by the terminal device, thereby effectively improving a transmission success rate of the downlink feedback information. In embodiments of the present disclosure, the method includes: sending, by the base station, indication information to the terminal device, where the indication information is used to indicate a target time-frequency resource location, the target time-frequency resource location is a time-frequency resource location at which the terminal device sends the downlink feedback information, and the downlink feedback information is used to feed back a reception status of downlink data that should be received by the terminal device; and receiving, by the base station, the downlink feedback information sent by the terminal device.

Abstract: Embodiments of this application provide a system message indication method, an apparatus, and a system, and relate to the field of communications technologies, to reduce a delay of updating a system message by a terminal device, and reduce power consumption. The method includes: generating, by a network device, notification information, where the notification information is used to indicate status information of first information, the first information includes at least one bit in a first system message, and a quantity of bits included in the first information is less than a quantity of bits included in the first system message; and sending, by the network device, the notification information to a terminal device. The embodiments of this application are applied to a process of changing a system message.

Abstract: This application provides a resource configuration method. The method includes: generating, by a network device, a first signal; and sending, by the network device, the first signal to a terminal device at a target resource location. The target resource location includes at least one subframe, and the at least one subframe is an invalid subframe. This implements that the network device sends the first signal in the invalid subframe. Based on a mechanism of the invalid subframe, a terminal device that does not need to receive the first signal may postpone the invalid subframe, and a terminal device that needs to receive the first signal may receive the first signal in the invalid subframe.

Abstract: Embodiments of the present invention disclose a signal sending method and apparatus and a signal receiving method and apparatus. The signal sending method includes: generating, by a network device, a first signal, where the first signal includes at least one sequence pair, each of the at least one sequence pair includes two sequences, and an element value of one sequence of the two sequences is a value obtained by calculating, according to a first calculation rule, an element value of the other sequence of the two sequences and an element value of a first sequence corresponding to the other sequence, where each sequence in the at least one sequence pair and the first sequence are complex sequences with lengths greater than 1; and sending, by the network device, the first signal to a terminal device.

Abstract: An embodiment of the present invention discloses a signal sending method, a signal receiving method, a terminal device, a base station, and a system, to ensure that a signal has a sufficiently large capacity when a PAPR is low, and reduce power consumption of the terminal device. The method in embodiments of the present invention includes: generating, by the terminal device, a first signal; performing, by the terminal device, code division processing on the first signal using a target code division sequence selected from a code division sequence set, to generate a second signal, where any two code division sequences in the code division sequence set meet orthogonality and shift orthogonality; and sending, by the terminal device, the second signal to the base station at a corresponding time-frequency resource location.

Abstract: An information sending and receiving method and a device, the sending method including generating a first signal, and sending the first signal on a first resource. The first resource includes a first part of resource elements (REs), and the first part of the REs comprises at least one of a first RE element or a second RE element. The first RE element comprises all REs corresponding to an orthogonal frequency division multiplexing (OFDM) symbol 0, symbol 1, and symbol 2 in each of subframes 0, 5, and 9 of each radio frame on a first carrier, the second RE element comprises an RE0, RE3, RE6, and RE9 in each of an OFDM symbol 4, 7, 8, and 11 in subframe 0 of each radio frame on the first carrier, and the first carrier is a carrier in a narrow band internet of things (NB-IoT) system.