Information Sending Method, Device and System

Abstract

An embodiment of the present invention provides an information sending method, including: a base station determines first information indicating a first carrier frequency deviation; the first carrier frequency deviation is the frequency deviation between the actual cell carrier center frequency and the cell carrier center frequency obtained by a terminal; the base station sends the first information to the terminal, and the first information is used to obtain the actual cell carrier center frequency. The technical solution provided by the embodiment of the present invention effectively improves the communication quality between the terminal and the base station.

Description

Technical Field

[0001] The present invention relates to wireless communication technologies, and particularly to a method, apparatus and system for information transmission. Background Art

[0002] The Internet of Things refers to a network that acquires information from the physical world by deploying various devices with certain sensing, computing, execution and communication capabilities, and performs information transmission, collaboration and processing to achieve the interconnection between people and things, and between things and things.

[0003] The narrow band-internet of things (NB-IoT) project is mainly used to study methods for supporting the Internet of Things with extremely low complexity and low cost in a cellular mobile network. In NB-IoT, when a terminal supporting NB-IoT communication communicates using the existing cellular mobile network architecture, there are three operation modes for the frequency band used relative to the original frequency band of the cellular mobile network: stand-alone operation mode, guardband operation mode, and in-band operation mode.

[0004] In the guardband operation mode or in-band operation mode, the communication quality of NB-IoT is not good. Summary of the Invention

[0005] The present invention provides an information indication method to effectively improve the communication quality of NB-IoT between a base station and a terminal.

[0006] In an embodiment of the present application, the base station determines first information indicating a first carrier frequency deviation, and sends the first information to the terminal. Wherein, the first carrier frequency deviation is the frequency deviation between the actual cell carrier center frequency and the cell carrier center frequency obtained by the terminal, and the terminal obtains the actual cell carrier center frequency according to the first information.

[0007] On the one hand, an embodiment of the present application provides a method for information transmission, including: the base station determines first information indicating a first carrier frequency deviation; the first carrier frequency deviation is the carrier frequency deviation between the actual cell carrier center frequency and the cell carrier center frequency obtained by the terminal; the base station sends the first information to the terminal, and the first information is used to obtain the actual cell carrier center frequency.

[0008] On the other hand, an embodiment of the present application provides another method for information transmission, including: a terminal receives first information sent by a base station indicating a first carrier frequency deviation; the first carrier frequency deviation is the carrier frequency deviation between the actual cell carrier center frequency and the cell carrier center frequency obtained by the terminal; the terminal obtains the actual cell carrier center frequency according to the first information.

[0009] Based on the above aspects, the present application also provides the following possible designs:

[0010] In a possible design, the above-mentioned cell carrier center frequency may be the cell uplink carrier center frequency, the cell downlink carrier center frequency, or the cell uplink carrier center frequency and the cell downlink carrier center frequency. When the terminal obtains the actual cell uplink carrier center frequency, it can initiate a random access process at the actual cell uplink carrier center frequency to obtain uplink synchronization with the base station; when the terminal obtains the actual cell downlink carrier center frequency, it can accurately perform processes such as sampling frequency synchronization.

[0011] In a possible design, the first information includes at least one of the value of the first carrier frequency deviation and the indication parameter of the first carrier frequency deviation; wherein, the indication parameter of the first carrier frequency deviation corresponds to the value of the first carrier frequency deviation. When the first information includes the value of the first carrier frequency deviation, the terminal can directly obtain the value of the first carrier frequency deviation without additional processing; when the first information includes the indication parameter of the first carrier frequency deviation, compared with the previous example, since the value of the first carrier frequency deviation may have a relatively large amount of data, if it is directly given to the terminal as the first information, there is a problem of waste of system resources, and the indication parameter of the first carrier frequency deviation with a relatively small amount of data can just solve this problem and improve the utilization rate of system resources.

[0012] In a possible design, the first information includes the root index value of the synchronization signal, and the value of the root index corresponds to the value of the first carrier frequency deviation. For example, the synchronization signal may be a secondary synchronization signal SSS, and the SSS includes a pair of ZC (Zadoff-Chu) sequences SSS1 and SSS2, and the root index includes the root index u1 of the SSS1 and the root index u2 of the SSS2.

[0013] In a possible design, the first information includes parameters such as the position and sequence type of the synchronization signal, and these parameters correspond to the value of the first carrier frequency deviation.

[0014] In a possible design, the first information includes a bandwidth parameter and a resource block index parameter, and the bandwidth parameter and the resource block index parameter correspond to the value of the first carrier frequency deviation. For example, the bandwidth parameter may be the bandwidth of a wireless mobile network, and the resource block index is the resource block index where the carrier of the cell is located within the channel bandwidth of the wireless mobile network system. The channel bandwidth parameter is an important parameter for the terminal, and it is sent to the terminal during the implementation of the technical solution of the present invention, facilitating the terminal to implement other functions based on the bandwidth parameter.

[0015] In a possible design, the base station sends a broadcast message or a dedicated message to the terminal, and the broadcast message or the dedicated message carries the first information; the terminal receives the broadcast message or the dedicated message.

[0016] In a possible design, when the first information includes the root index value of the synchronization signal, the first information is carried in the synchronization signal. For example, for the SSS, during downlink synchronization, the base station sends the SSS to the terminal. In this case, if the first information is advanced to the SSS sending stage in the downlink synchronization phase, it ensures that the terminal obtains the first information as early as possible and obtains the actual downlink carrier center frequency of the cell in the downlink synchronization phase, avoiding the failure of a series of subsequent communication processes caused by the terminal's inability to receive the broadcast message of the cell due to downlink synchronization failure.

[0017] In a possible design, the carrier center frequency of the cell obtained by the terminal is obtained when the terminal receives the synchronization signal.

[0018] In a possible design, the carrier center frequency of the cell obtained by the terminal is obtained by the terminal receiving the broadcast message or the dedicated message.

[0019] In a possible design, the above method further includes: the base station determines second information indicating a second carrier frequency deviation and sends the second information to the terminal. Wherein, the second carrier frequency deviation is the carrier frequency deviation between the actual carrier center frequency of the heterogenous frequency cell and the carrier center frequency of the heterogenous frequency cell obtained by the terminal, and the terminal obtains the actual carrier center frequency of the heterogenous frequency cell according to the second information. The terminal determines the actual carrier center frequency of the heterogenous frequency cell according to the second information, which can quickly and accurately perform cell search for the heterogenous frequency cell and make full preparations for possible subsequent cell handovers.

[0020] In a possible design, the above cell is a cell supporting NB-IoT communication.

[0021] On the other hand, an embodiment of the present invention provides a base station, which has the function of implementing the base station behavior in the above method design. The function can be implemented by hardware or by hardware executing corresponding software. The hardware or software includes one or more units corresponding to the above functions.

[0022] In a possible design, the structure of the base station includes a processor and a transmitter. The processor is configured to support the base station to execute the corresponding functions in the above method. The transmitter is used to support the communication between the base station and the terminal, and send the information or instructions involved in the above method to the terminal. The base station may further include a memory, which is used to be coupled with the processor and stores the necessary program instructions and data of the base station.

[0023] On another hand, an embodiment of the present invention provides a terminal, which has the function of implementing the terminal behavior in the above method design. The function can be implemented by hardware or by hardware executing corresponding software. The hardware or software includes one or more units corresponding to the above functions. The module can be software and / or hardware

[0024] In a possible design, the structure of the terminal includes a receiver and a processor. The processor is configured to support the terminal to execute the corresponding functions in the above method. The transmitter is used to support the communication between the terminal and the base station, and receive the information or instructions involved in the above method sent by the base station. The terminal may further include a memory, which is used to be coupled with the processor and stores the necessary program instructions and data of the base station.

[0025] On another hand, an embodiment of the present invention provides a communication system, which includes the base station and the terminal described in the above aspects.

[0026] On yet another hand, an embodiment of the present invention provides a computer storage medium, which is used to store computer software instructions for the above base station and includes a program for executing the design in the above aspects.

[0027] On yet another hand, an embodiment of the present invention provides a computer storage medium, which is used to store computer software instructions for the above terminal and includes a program for executing the design in the above aspects.

[0028] On yet another hand, an embodiment of the present invention provides a chip system, including: at least one processor, a memory, an input / output part, and a bus; the at least one processor obtains instructions in the memory through the bus to implement the design functions of the base station involved in the above method.

[0029] In another aspect, an embodiment of the present invention provides a chip system, including: at least one processor, a memory, an input / output part, and a bus; the at least one processor obtains instructions in the memory through the bus for implementing the design functions of the terminal involved in the above method.

[0030] The technical solution provided by the embodiment of the present invention enables the terminal to obtain the actual cell carrier center frequency by the base station indicating the first information of the first frequency deviation to the terminal. On this actual cell carrier center frequency, communication processes such as synchronization between the terminal and the base station are carried out, which will avoid adverse effects caused by the cognitive deviation of the terminal to the cell carrier center frequency, such as uplink synchronization failure, etc. The communication quality between the terminal and the base station is effectively improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the following drawings are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0032] FIG. 1(a) is a schematic diagram of an independent operation mode supported by narrowband Internet of Things according to an embodiment of the present invention;

[0033] FIG. 1(b) is a schematic diagram of a guard band operation mode supported by narrowband Internet of Things according to an embodiment of the present invention;

[0034] FIG. 1(c) is a schematic diagram of an in-band operation mode supported by narrowband Internet of Things according to an embodiment of the present invention;

[0035] Figure 2 is a system architecture diagram provided by an embodiment of the present invention;

[0036] Figure 3 is an application scenario provided by an embodiment of the present invention;

[0037] Figure 4 is a schematic flowchart of an information indication method provided by an embodiment of the present invention;

[0038] Figure 5 is a schematic diagram of information parameter comparison provided by an embodiment of the present invention;

[0039] Figure 6 is a schematic flowchart of another information indication method provided by an embodiment of the present invention;

[0040] Figure 7 is a schematic structural diagram of a base station provided by an embodiment of the present invention;

[0041] Figure 8 A schematic structural diagram of a terminal provided by an embodiment of the present invention;

[0042] Figure 9 Another schematic structural diagram of a base station provided by an embodiment of the present invention;

[0043] Figure 10 Another schematic structural diagram of a terminal provided by an embodiment of the present invention. Detailed implementation manners

[0044] Cellular Internet of Things (CIoT) realizes Internet of Things communication based on existing wireless communication systems, that is, the system architecture on which its system operates is similar to that of wireless communication systems, such as Long-Term Evolution (LTE) systems. NarrowBand Internet of Things (NB-IoT) involved in the present invention originates from the proposal in the 69th meeting of the Radio Access Network (RAN) of the 3rd Generation Partnership Project (3GPP). The goal of NB-IoT is to define a wireless access method for cellular Internet of Things to achieve large coverage, low latency, and low-cost communication. rd generation partnership project, 3GPP) Radio Access Network (RAN) #69 meeting proposal. The goal of NB-IoT is to define a wireless access method for cellular Internet of Things to achieve large coverage, low latency, and low-cost communication.

[0045] It is pointed out in the proposals related to NB-IoT in the 69th meeting of 3GPP RAN that NB-IoT should support three different operation modes:

[0046] 1. Stand-alone operation: NB-IoT operates on an independent carrier frequency band, as shown in Figure 1(a).

[0047] 2. Guard band operation: NB-IoT operates on the resource blocks not utilized in the LTE carrier guard band, as shown in Figure 1(b).

[0048] 3. In-band operation: NB-IoT operates on the resource blocks of the LTE carrier frequency band (i.e., the channel bandwidth), as shown in Figure 1(c). In this operation mode, for example, NB-IoT can use a certain resource block within the LTE carrier frequency band as the uplink carrier frequency band of NB-IoT and use another resource block within the LTE carrier frequency band as the downlink carrier frequency band of NB-IoT.

[0049] Figure 2 A system architecture diagram provided by an embodiment of the present invention. As Figure 2As shown, the terminal accesses the external network through a radio access network (RAN) and a core network (CN). The technology described in the present invention can be applied to the NB-IoT system. Of course, it can also be applied to other wireless communication systems using various wireless access technologies, such as systems using access technologies such as code division multiple access, frequency division multiple access, time division multiple access, orthogonal frequency division multiple access, single-carrier frequency division multiple access, etc., and subsequent evolved systems, such as the fifth-generation 5G system, etc.

[0050] In this application, the nouns "network" and "system" are often used interchangeably, but those skilled in the art can understand their meanings. For clarity, the LTE system is taken as an example here for illustration. In the LTE system, the evolved universal terrestrial radio access (E-UTRA) network serves as the radio access network, and the evolved packet core (EPC) serves as the core network. Since the system architecture in which the NB-IoT system operates is similar to that of the LTE system, the above description of the LTE system architecture also applies to the NB-IoT system.

[0051] Figure 3 An application scenario of an embodiment of the present invention is shown. Figure 3 It includes a base station and terminals 1 to 6. A base station is a device deployed in a radio access network to provide wireless communication functions for terminals. The base station can include various forms of macro base stations, micro base stations, relay stations, access points, etc. In systems using different wireless access technologies, the names of devices with base station functions may be different. For example, in the LTE system, it is called an evolved Node B (eNodeB), and in the third-generation network, it is called a Node B, etc. A terminal can include various handheld devices, vehicle-mounted devices, wearable devices, computing devices or other processing devices connected to a wireless modem with wireless communication functions, as well as various forms of mobile stations (Mobile station, MS), user equipment (User Equipment, UE), etc. As Figure 3 shown, the base station can communicate with any one of terminals 1 to 6. In addition, terminals 4, 5, and 6 can form a small system, in which terminal 5 can communicate with terminals 4 and 6 respectively.

[0052] Some explanations are now made for the nouns and concepts related to this application.

[0053] The cell carrier center frequency involved in this application, which is also the cell carrier center frequency point, can also be simply referred to as the cell carrier frequency in some cases. The cell carrier center frequency includes the cell uplink carrier center frequency and the cell downlink carrier center frequency.

[0054] In this application, the cell supporting NB-IoT is simply referred to as the NB-IoT cell.

[0055] In the existing LTE system, communication is only carried out on the carrier frequency band specifically allocated for use, that is, in a form similar to the above independent operation mode. According to the existing 3GPP technical standard (TS) 36.104, the cell carrier center frequency must be an integer multiple of 100 kilohertz (kHz), that is, it meets the channel raster rule. The cell uplink carrier center frequency (hereinafter referred to as the uplink carrier frequency) and the cell downlink carrier center frequency (hereinafter referred to as the downlink carrier frequency) are identified by the E-UTRA absolute radio frequency channel number (EARFCN), and the value range of EARFCN is 0 - 65535. The relationship between EARFCN and the downlink carrier frequency (unit: megahertz (MHz)) is given by formula (1): F DL = F DL_low + 0.1(N DL – N Offs-DL ) where F DL_low and N Offs-DL are given in Table 5.7.3-1 of 3GPP TS36.104, F DL is the downlink carrier frequency, and N DL is the downlink EARFCN; the relationship between EARFCN and the uplink carrier frequency (unit: megahertz (MHz)) is given by formula (2): F UL = F UL_low + 0.1(N UL – N Offs-UL ) where F UL_low and N Offs-UL are given in Table 5.7.3-1 of 3GPP TS36.104, F UL is the uplink carrier frequency, and N UL is the uplink EARFCN.

[0056] When the terminal performs cell search, it will search on carrier frequencies that are integer multiples of 100 kHz. Once a cell is found, the terminal will attempt to camp on that cell and read the broadcast message sent by the base station through that cell. The broadcast message contains the uplink EARFCN of that cell. The terminal can obtain the uplink carrier center frequency of that cell according to formula (2) and then initiate a random access procedure on that carrier center frequency to establish a connection with the network. In addition, the broadcast message may also contain the downlink EARFCN of other inter-frequency cells. Similarly, based on the downlink EARFCN of other inter-frequency cells, the terminal can determine the downlink carrier center frequencies of these inter-frequency cells, quickly search for these inter-frequency cells, and perform subsequent cell reselection or cell handover procedures.

[0057] The above process will have the following problems for the NB-IoT system: When operating in operation mode 2 or 3, the NB-IoT cell carrier center frequency cannot fall on an integer multiple of 100 kHz. That is, the value of the NB-IoT cell carrier center frequency (this frequency can be called the actual cell carrier center frequency) deviates from the value that could be used as the cell carrier center frequency in the original LTE system. Therefore, when the terminal searches for an NB-IoT cell, although it synchronizes with the base station in the downlink on the NB-IoT cell carrier center frequency, the terminal will misidentify the NB-IoT cell carrier center frequency as an integer multiple of 100 kHz for storage (this frequency can be called the cell carrier center frequency obtained by the terminal), which may lead to failures such as sampling frequency synchronization in the future; and there is a deviation between the uplink carrier center frequency of the NB-IoT cell calculated according to the EARFCN in the broadcast message (this frequency can also be called the cell carrier center frequency obtained by the terminal) and the uplink carrier center frequency of this NB-IoT cell (this frequency can also be called the actual cell carrier center frequency). Then, if the terminal initiates a random access procedure based on the calculated uplink carrier center frequency of the NB-IoT cell, it is very likely to cause random access failure, and further lead to uplink synchronization failure between the terminal and the base station. Similarly, there is a deviation between the downlink carrier center frequency of the NB-IoT inter-frequency cell obtained by the terminal and the actual downlink carrier center frequency of this NB-IoT inter-frequency cell, which will also lead to failures in subsequent cell reselection or cell handover. In this way, the communication quality of NB-IoT is seriously affected.

[0058] Based on the above problems, Figure 4 A flowchart of an information indication method is provided. This method can be applied to Figure 2 the system architecture shown in Figure 3 and the application scenarios shown in

[0059] 401. The base station determines first information indicating a first carrier frequency deviation; the first carrier frequency deviation is the frequency deviation between the actual cell carrier center frequency and the cell carrier center frequency obtained by the terminal.

[0060] 402. The base station sends the first information to the terminal, and the first information is used to obtain the actual cell carrier center frequency.

[0061] 403. The terminal obtains the actual cell carrier center frequency according to the first information.

[0062] Hereinafter, taking this cell as a cell in the NB-IoT system and the NB-IoT system operating in operation mode 2 or 3 as an example, a detailed description will be given.

[0063] The base station itself can know the actual cell carrier center frequency. The base station obtains the frequency that is an integer multiple of 100 KHz closest to the actual cell carrier center frequency according to the actual cell carrier center frequency, and can also obtain the EARFCN corresponding to the frequency that is an integer multiple of 100 KHz closest to it according to formula (1) or (2) and Table 5.7.3-1 in 3GPP TS36.104. Among them, the actual cell carrier center frequency can be divided into the actual cell downlink carrier center frequency and the actual cell uplink carrier center frequency; EARFCN includes downlink EARFCN and uplink EARFCN. According to the actual cell carrier center frequency and the frequency that is an integer multiple of 100 KHz closest to the actual cell carrier center frequency, the base station can obtain the value of the first carrier frequency deviation.

[0064] It should be noted that the frequency that is an integer multiple of 100 KHz closest to the actual cell carrier center frequency in the above text is the cell carrier center frequency obtained by the terminal. It can be obtained by the terminal by being carried in a broadcast message or a dedicated message, or can also be obtained by the terminal when receiving a synchronization signal. When it is obtained by the terminal by being carried in a broadcast message or a dedicated message, the base station can inform the terminal in the way of carrying the above-obtained EARFCN in the broadcast message.

[0065] The base station needs to notify the terminal of the value of the first carrier frequency deviation obtained above so that the terminal can accurately know the actual cell carrier center frequency. The base station can send the first information of the first carrier frequency deviation corresponding to the first carrier frequency deviation value to the terminal.

[0066] As a first example, the first information determined by the base station includes the value of the first carrier frequency deviation. The advantage of this method is that it is convenient and easy to implement, and the terminal can directly obtain the value of the first carrier frequency deviation without additional processing.

[0067] As a second example, the first information determined by the base station includes an indication parameter of the first carrier frequency deviation, and the indication parameter of the first carrier frequency deviation corresponds to the value of the first carrier frequency deviation. This correspondence can be pre-agreed between the base station and the terminal, or can be pre-configured separately in the base station and the terminal. For example:

[0068] According to the research on the NB-IoT system and the LTE system, the base station can preset several possible values of the first carrier frequency deviation, and map these several values one by one to the indication parameter of the first carrier frequency deviation.

[0069]

[0070] Table 1

[0071] As shown in Table 1, the indication parameter of the first carrier frequency deviation and the value of the first carrier frequency deviation correspond one by one from left to right. As a specific example, it can be seen from the above table that the indication parameter of the first carrier frequency deviation being "2" corresponds to the value of the first carrier frequency deviation of -47.5 kHz, and so on. After the base station obtains the value of the first carrier frequency deviation, it can determine the indication parameter of the first carrier frequency deviation according to Table 1 as the first information. The advantage of the above method is that since the possible data volume of the value of the first carrier frequency deviation may be relatively large, if it is directly given to the terminal as the first information, there will be a problem of waste of system resources, while the indication parameter of the first carrier frequency deviation with a relatively small data volume can just solve this problem and improve the utilization rate of system resources.

[0072] As a third example, the first information determined by the base station includes the root index value of the synchronization signal. For example, the first carrier frequency deviation information can be obtained through the root index value in the secondary synchronization signal (SSS). For example, from the set {ul, u2} of the root indices ul and u2 of SSS1 and SSS2 that make up the SSS, this set corresponds to the value of the first carrier frequency deviation. This correspondence can be pre-agreed between the base station and the terminal, or can be pre-configured separately in the base station and the terminal.

[0073] In the NB-IoT system, the SSS is a pair of ZC (zadoff-Chu) sequences, SSS1 and SSS2. The basic expression of the ZC sequence with length L is:

[0074] zc(n) = e -jπun(n+1+2q) / L , n = 0, 1,..., L - 1, q ∈ Z, u ∈ Z

[0075] Among them, u is the root index of the ZC sequence, and q is the offset parameter. For each SSS, there are L - 1 possible values for u. Then, different values of the first downlink carrier frequency deviation can be distinguished by different root indexes of the ZC sequence. Specifically, a set of values of the root indexes u1 of SSS1 and u2 of SSS2, denoted as {u1, u2}, can be mapped one by one to several possible numerical values of the difference of the first carrier frequency deviation pre-known by the base station as the first information, that is, each value of the first downlink carrier frequency deviation corresponds to a possible {u1, u2}. For example, {1, 2} corresponds to -47.5 kHz.

[0076] As a fourth example, the first information determined by the base station includes the channel bandwidth parameter and the resource block (RB) index; for example, the channel bandwidth parameter is the value of the channel bandwidth of the LTE system, and the resource block index is the index of the resource block where the carrier of the cell is located within the channel bandwidth of the LTE system. Further, referring to Fig. 1(c), the channel bandwidth of the LTE system is divided into 16 resource blocks, and these resource blocks are numbered from left to right in ascending order of frequency, forming an index from 0 to 15. In the figure, the carrier of the cell occupies the 4th resource block in the channel bandwidth of the LTE system carrier, then at this time, the corresponding resource block index is 3.

[0077] The channel bandwidth parameter and the resource block index correspond to the value of the first carrier frequency deviation, and this correspondence relationship can be pre-agreed by the base station and the terminal, or can be pre-configured in the base station and the terminal respectively. For example:

[0078] The channel bandwidth of the LTE system has the following values: 1.4 MHz, 3 MHz, 5 MHz, 10 MHz, 15 MHz, and 20 MHz. The available number of RBs corresponding to the channel bandwidth can be obtained from Table 5.6 - 1 in 3GPP TS36.101.

[0079] Channel bandwidth (MHz) 1.4 3 5 10 15 20 <![CDATA[Number N of available RBs RB > 6 15 25 50 75 100

[0080] 3GPP TS36.101 Table 5.6 - 1

[0081] These RBs can be indexed and numbered in ascending order of frequency (for example, in ascending order from low to high, that is, from left to right as shown in Fig. 1(c)), for example, 0, 1,......, N RB -1.

[0082] When the channel bandwidth B of the LTE system LTE is 3 MHz, 5 MHz or 15 MHz,

[0083] If the resource block serial number in the first carrier frequency deviation information Then the value of the first carrier frequency deviation Δf = 0;

[0084] If Then

[0085]

[0086] If Then

[0087]

[0088] Wherein, round100{x} represents a calculation that results in a value that is an integer multiple of 100 and has the smallest absolute difference from x.

[0089] When the channel bandwidth B of the LTE system LTE is 1.4 MHz, 10 MHz or 20 MHz,

[0090] If Then

[0091]

[0092] If Then

[0093]

[0094] The base station itself knows the bandwidth and resource block index of the LTE system and sends them to the terminal as the first information. The channel bandwidth parameter is an important parameter for the terminal and is sent to the terminal during the implementation of the technical solution of the present invention to facilitate the terminal to implement other functions according to the bandwidth parameter.

[0095] The first information described in this application can be used to indicate the first downlink carrier frequency deviation, the first uplink carrier frequency deviation, or both the first downlink carrier frequency deviation and the first uplink carrier frequency deviation.

[0096] In the actual application process of this application, the value of the first carrier frequency deviation between the actual cell carrier center frequency and the carrier center frequency obtained by the terminal may not be as large as the value listed in the second row and second column of Table 1 and may be a subset of the listed value. Then, for the second or third example, it can be further simplified.

[0097] For example, for the second example, Table 1 can be simplified to Table 2, that is, the first frequency deviation value here takes a part of the original value, and this part is the first frequency deviation value that most frequently appears in actual applications:

[0098] Indicator parameter of the first carrier frequency deviation 1,2,3,4 Value of the first carrier frequency deviation (kHz) -7.5,-2.5,2.5,7.5

[0099] Table 2

[0100] For another example, for the third example, as Figure 5 shown, the set {u1, u2} has 4 values, corresponding to 4 first carrier frequency deviation values of -7.5 kHz, -2.5 kHz, 2.5 kHz, and 7.5 kHz respectively.

[0101] The advantage of the above approach is that, according to the actual system situation, it maximizes resource utilization and avoids unnecessary system overhead.

[0102] According to the content included in the first information determined by the base station, the base station can send the first information to the terminal in the following manner.

[0103] The base station can carry the first information in the broadcast message or dedicated message sent by the base station to the cell and send it to the terminal.

[0104] It should be noted that in actual operation, the first information may include at least one of the value of the first carrier frequency deviation, the indication parameter of the first carrier frequency deviation, the root index value of the SSS, the channel bandwidth of the radio mobile network, and the resource block index of the radio mobile network.

[0105] As an example, when the first information includes the root index value of the SSS, the base station sending the first information to the terminal includes: the base station sending the SSS signal to the terminal. This SSS signal is generated by a specific root index, and the base station can indicate the first information of the first frequency deviation by sending the SSS to the terminal. For example, when the SSS consists of SSS1 and SSS2, when the base station sends the secondary synchronization signal to the terminal, the terminal can obtain the value of the first carrier frequency deviation corresponding to the set composed of the root indices of SSS1 and SSS2. During the synchronization process, the terminal compensates for the carrier frequency deviation and sampling frequency deviation based on the synchronization estimation result. However, due to the carrier frequency deviation problem in the NB-IoT system, the compensation for the sampling frequency offset is an over-compensation rather than a correct compensation, which may lead to the inability to receive the message sent by the base station. And the above two example methods finally require the terminal to receive the message sent by the base station after obtaining the downlink synchronization to indicate the first carrier frequency deviation information. In this case, if the first information is advanced to the SSS sending stage in the downlink synchronization stage, it ensures that the terminal obtains the first information as early as possible and obtains the actual cell downlink carrier center frequency in the downlink synchronization stage, avoiding the failure of subsequent communication processes.

[0106] At this time, the base station can also use the position of the SSS (for example, different subframe numbers where the SSS is located correspond to different values of the first carrier frequency deviation, or different relative positions between multiple SSSs correspond to different values of the first carrier frequency deviation, etc.), the sequence type (for example, different types of SSS sequences correspond to different values of the first carrier frequency deviation), or other parameters as the first information to indicate the first frequency deviation to the terminal.

[0107] The terminal receives the first information sent by the base station.

[0108] The terminal that obtains the first information can restore the value of the first carrier frequency deviation, and then obtain the actual cell carrier center frequency.

[0109] According to the first example in 401, the first information includes the value of the first downlink carrier frequency deviation.

[0110] The terminal receives the first information through a broadcast message or a dedicated message. At this time, the value of the first carrier frequency deviation is the value of the first carrier frequency deviation that needs to be restored.

[0111] At this time, the terminal can obtain the actual cell carrier center frequency by adding the value of the first carrier frequency deviation to the obtained cell carrier center frequency. Specifically, the following formula (7) can be referred to:

[0112] The carrier center frequency f of the cell NB-IoT = f0 + Δf

[0113] where f0 is the cell carrier center frequency obtained by the terminal, and Δf is the value of the first carrier frequency deviation.

[0114] According to the second example in 401, the first information includes the indication parameter of the first carrier frequency deviation.

[0115] As can be seen from 402, the terminal receives the first information through a broadcast message or a dedicated message. At this time, the terminal looks up Table 1 or Table 2 according to the indication parameter of the first carrier frequency deviation to find the value of the first carrier frequency deviation corresponding to the indication parameter of the first carrier frequency deviation. Then, the actual cell carrier center frequency can be obtained according to formula (7).

[0116] According to the third example in 401, the first information includes the root index value of the SSS. Here, an example is given to illustrate that the first carrier frequency deviation information is indicated by a pair of root indices u1 and u2 in a pair of secondary synchronization signals SSS1 and SSS2 that make up the SSS.

[0117] When the terminal receives the first information through a broadcast message or a dedicated message, it can obtain the value of the first carrier frequency deviation according to the corresponding relationship pre-agreed with the base station. Then, the actual cell carrier center frequency can be obtained according to formula (7).

[0118] The terminal receives SSS1 and SSS2. The types of SSS1 and SSS2 can be ZC sequences. The terminal attempts to match them with different root exponents to restore the two received ZC sequences. Finally, the root exponents that can restore these two ZC sequences are obtained as the root exponents of SSS1 and SSS2. Among them, the root exponent of SSS1 is u1, and the root exponent of SSS2 is u2. According to the corresponding relationship between {u1, u2} and the value of the first carrier frequency deviation, the terminal can obtain the value of the first carrier frequency deviation. The terminal corrects the synchronization estimation result and the synchronization error compensation operation according to the obtained value of the first carrier frequency deviation, that is, by using formula (7), the actual cell carrier center frequency is obtained. At this time, the actual cell carrier center frequency is the actual downlink carrier center frequency of the cell.

[0119] According to the fourth example in 401, the first information includes a bandwidth parameter (such as the channel bandwidth of the LTE system) and an RB index parameter.

[0120] As can be seen from 402, the terminal receives the first information through a broadcast message or a dedicated message. At this time, according to the channel bandwidth and the RB index number of the LTE system, the terminal can restore the value of the first downlink carrier frequency deviation by referring to formulas (3)-(6). Then, the actual cell carrier center frequency can be obtained according to formula (7).

[0121] After the terminal obtains the actual cell carrier center frequency, it can perform processes such as uplink synchronization and sampling frequency synchronization with the base station at the actual cell carrier center frequency, and then achieve high-quality communication with the base station.

[0122] The technical solution provided in this embodiment enables the terminal to obtain the actual cell carrier center frequency by the base station indicating the first information of the first frequency deviation to the terminal. At this actual cell carrier center frequency, the terminal and the base station perform communication processes such as synchronization, which will avoid adverse effects caused by the terminal's cognitive deviation of the cell carrier center frequency, such as uplink synchronization failure. It effectively improves the communication quality between the terminal and the base station.

[0123] Figure 6 A schematic flowchart of another information indication method is provided. This method can be applied to Figure 2 the system architecture shown in Figure 3 and the application scenario shown in Figure 4 and this method includes steps 401-403 of the method shown in

[0124] 601. The base station determines second information indicating a second carrier frequency deviation; the second carrier frequency deviation is the frequency deviation between the actual carrier center frequency of the inter-frequency cell and the carrier center frequency of the inter-frequency cell obtained by the terminal.

[0125] 602. The base station sends the second information to the terminal, and the second information is used to obtain the actual carrier center frequency of the inter-frequency cell.

[0126] 603. The terminal obtains the actual carrier center frequency of the inter-frequency cell according to the second information.

[0127] Still taking this cell as a cell in the NB-IoT system, and the NB-IoT system operating in operation mode 2 or 3 as an example, a detailed description is given below.

[0128] This method can be applied to the cell handover process. Similarly, when the terminal searches for an inter-frequency cell for cell handover, there will be a deviation between the carrier center frequency of the inter-frequency cell obtained by the terminal and the actual value. The execution manner of this step is basically the same as that of 401. Here, the second information of the inter-frequency cell of this cell is determined, which is used to indicate the second carrier frequency deviation. The second carrier frequency deviation is the frequency deviation between the actual carrier center frequency of the inter-frequency cell and the carrier center frequency of the inter-frequency cell obtained by the terminal. This second information can be sent to the terminal through the broadcast message or dedicated message of this cell.

[0129] The value of the second carrier frequency deviation of the uplink carrier center frequency of the inter-frequency cell or the indication parameter of the second frequency deviation can be obtained through the broadcast message or dedicated message of the inter-frequency cell after the terminal switches to the inter-frequency cell.

[0130] The terminal receives the second information sent by the base station.

[0131] The terminal obtains the value of the second carrier frequency deviation according to the second information, and further obtains the carrier center frequency of the inter-frequency cell.

[0132] The specific execution manner of this step is basically the same as that of 403, and will not be elaborated here.

[0133] The terminal determines the actual carrier center frequency of the inter-frequency cell according to the second information, can quickly and accurately search for the inter-frequency cell, and make full preparations for possible subsequent cell handover.

[0134] Of course, the terminal obtaining the actual carrier center frequency of the inter-frequency cell can also be used for other processes other than cell handover, and no limitation is made here.

[0135] The above mainly introduces the solution provided by the embodiments of the present invention from the perspective of the interaction between each base station and the terminal. It can be understood that in order to implement the above functions, the base station, the terminal, etc. include the corresponding hardware structures and / or software modules for executing each function. Those skilled in the art should easily realize that, in combination with the units and algorithm steps of each example described in the embodiments disclosed in this article, the present invention can be implemented in the form of hardware or a combination of hardware and computer software. Whether a certain function is executed in the manner of hardware or computer software driving hardware depends on the specific application and design constraints of the technical solution. Professional technicians can use different methods to implement the described functions for each specific application, but such implementation should not be considered to exceed the scope of the present invention.

[0136] Figure 7 Fig. shows a possible structural schematic diagram of the base station involved in the above embodiments.

[0137] The base station includes a transmitter / receiver 701, a controller / processor 702, a memory 703, and a communication unit 704. The transmitter / receiver 701 is used to support the transceiver of information between the base station and the terminal, and to support radio communication between the terminal and other terminals. The controller / processor 702 executes various functions for communicating with the terminal. In the uplink, the uplink signal from the terminal is received via the antenna, demodulated by the receiver 701, and further processed by the controller / processor 702 to recover the service data and signaling information sent by the terminal. In the downlink, the service data and signaling messages are processed by the controller / processor 702, modulated by the transmitter 701 to generate a downlink signal, and transmitted to the terminal via the antenna. The controller / processor 702 also executes Figure 4 and Figure 6 the processing procedures related to the base station and / or other procedures for the technologies described in this application. The memory 703 is used to store the program code and data of the base station. The communication unit 704 is used to support the communication between the base station and other network devices.

[0138] It can be understood that Figure 7 only a simplified design of the base station is shown. In practical applications, the base station may include any number of transmitters, receivers, processors, controllers, memories, communication units, etc., and all base stations that can implement the present invention are within the protection scope of the present invention.

[0139] Figure 8 Fig. shows a possible structural schematic diagram of the terminal involved in the above embodiments. The terminal includes a transmitter 801, a receiver 802, a controller / processor 803, a memory 804, and a modem processor 805.

[0140] The transmitter 801 adjusts (e.g., analog conversion, filtering, amplification, upconversion, etc.) the output samples and generates an uplink signal, which is transmitted via the antenna to the base station described in the above embodiments. On the downlink, the antenna receives the downlink signal transmitted by the access network device in the above embodiments. The receiver 802 adjusts (e.g., filtering, amplification, downconversion, and digitization, etc.) the signal received from the antenna and provides input samples. In the modulation and demodulation processor 805, the encoder 806 receives the service data and signaling messages to be transmitted on the uplink, and processes (e.g., formats, encodes, and interleaves) the service data and signaling messages. The modulator 807 further processes (e.g., symbol mapping and modulation) the encoded service data and signaling messages and provides output samples. The demodulator 809 processes (e.g., demodulates) the input samples and provides symbol estimates. The decoder 808 processes (e.g., deinterleaves and decodes) the symbol estimates and provides the decoded data and signaling messages sent to the terminal. The encoder 806, modulator 807, demodulator 809, and decoder 808 can be implemented by the synthesized modulation and demodulation processor 805. These units perform processing according to the radio access technology adopted by the radio access network (e.g., access technologies of LTE and other evolved systems).

[0141] The controller / processor 803 controls and manages the operations of the terminal, is used to execute the processing performed by the terminal in the above embodiments, and controls the transmitter 801 and the receiver 802 to complete Figure 4 and Figure 6 the operations performed by the terminal in

[0142] Figure 9 For the base station 900 provided by an embodiment of the present invention, the base station 900 may include a processing unit 910 and a transceiver unit 920. Among them, the processing unit 910 can implement Figure 7 the functions of the controller / processor 702 of the base station in Figure 7 ; the transceiver unit 920 can implement

[0143] Figure 10 For the terminal 1000 provided by an embodiment of the present invention, the terminal 1000 may include a processing unit 1010 and a transceiver unit 1020. Among them, the processing unit 1010 can implement Figure 8 the functions of the controller / processor 803 of the terminal in Figure 8 ; the transceiver unit 1020 can implement

[0144] Those skilled in the art can also understand that the various illustrative logical blocks and steps listed in the embodiments of the present invention can be implemented by electronic hardware, computer software, or a combination of both. To clearly show the interchangeability of hardware and software, the above-mentioned various illustrative components and steps have been generally described in terms of their functions. Whether such functions are implemented by hardware or software depends on the specific application and the design requirements of the entire system. Those skilled in the art can use various methods to implement the described functions for each specific application, but such implementation should not be construed as exceeding the scope protected by the embodiments of the present invention.

[0145] The various illustrative logical blocks, modules, and circuits described in the embodiments of the present invention can be implemented or operated by a general-purpose processing unit, a digital signal processing unit, an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA), or other programmable logic devices, discrete gate or transistor logic, discrete hardware components, or any combination of the above designs to perform the described functions. The general-purpose processing unit can be a microprocessing unit. Optionally, the general-purpose processing unit can also be any conventional processing unit, controller, microcontroller, or state machine. The processing unit can also be implemented by a combination of computing devices, such as a digital signal processing unit and a microprocessing unit, multiple microprocessing units, one or more microprocessing units combined with a digital signal processing unit core, or any other similar configuration.

[0146] The steps of the methods or algorithms described in the embodiments of the present invention can be directly embedded in hardware, software modules executed by a processing unit, or a combination of both. The software modules can be stored in a RAM memory, a flash memory, a ROM memory, an EPROM memory, an EEPROM memory, a register, a hard disk, a removable disk, a CD-ROM, or any other form of storage medium in the art. Exemplarily, the storage medium can be connected to the processing unit so that the processing unit can read information from the storage medium and write information to the storage medium. Optionally, the storage medium can also be integrated into the processing unit. The processing unit and the storage medium can be configured in an ASIC, and the ASIC can be configured in a user terminal. Optionally, the processing unit and the storage medium can also be configured in different components of the user terminal.

[0147] In one or more exemplary designs, the functions described in the embodiments of the present invention may be implemented in hardware, software, firmware, or any combination of the three. If implemented in software, these functions may be stored on a computer-readable medium or transmitted as one or more instructions or codes on a computer-readable medium. A computer-readable medium includes both computer storage media and communication media that facilitate transfer of a computer program from one place to another. The storage media may be any available media that can be accessed by a general-purpose or special-purpose computer. For example, such computer-readable media may include, but are not limited to, RAM, ROM, EEPROM, CD-ROM or other optical disk storage, magnetic disk storage or other magnetic storage devices, or any other medium that can be used to carry or store program code in the form of instructions or data structures and that can be read by a general-purpose or special-purpose computer, or a general-purpose or special-purpose processing unit. In addition, any connection can be properly defined as a computer-readable medium. For example, if software is transmitted from a website, server, or other remote source via a coaxial cable, fiber optic cable, twisted pair, digital subscriber line (DSL), or wirelessly such as infrared, wireless, and microwave, it is also included within the defined computer-readable medium. The disk and disc include compact disk, laser disk, optical disk, DVD, floppy disk, and Blu-ray disk. The disk usually replicates data magnetically, while the disc usually replicates data optically with a laser. The above combinations may also be included in the computer-readable medium.

[0148] The foregoing description of the present invention's specification enables those skilled in the art to utilize or implement the content of the present invention. Any modifications based on the disclosed content should be considered obvious to those skilled in the art. The basic principles described in the present invention can be applied to other variations without departing from the essence and scope of the present invention. Therefore, the content disclosed in the present invention is not limited to the described embodiments and designs, but can be extended to the maximum scope consistent with the principles of the present invention and the disclosed new features.

Claims

1. A communication method, characterized in that, Comprising: Receiving, by a first cell, first information from a base station indicating a first carrier frequency deviation, where the first carrier frequency deviation is a carrier frequency deviation between an actual downlink carrier frequency of a second cell and an acquired downlink carrier frequency of the second cell; Obtaining the actual downlink carrier frequency of the second cell according to the first information; Wherein, the second cell is a different-frequency cell of the first cell.

2. The method according to claim 1, wherein The downlink carrier frequency of the second cell is used for cell reselection or cell handover.

3. The method according to claim 1 or 2, characterized in that, Receiving the first information through a broadcast message of the first cell.

4. The method according to claim 1 or 2, characterized in that, Further comprising: Receiving, by the second cell, second information from the base station indicating a second carrier frequency deviation, where the second carrier frequency deviation is a carrier frequency deviation between an actual uplink carrier frequency of the second cell and an acquired uplink carrier frequency of the second cell.

5. The method according to claim 4, wherein Receiving the second information through a broadcast message or a dedicated message of the second cell.

6. The method according to any one of claims 1 to 2 and 5, characterized in that, The first information includes a first indication parameter, and a value of the first carrier frequency deviation corresponds to the first indication parameter.

7. The method according to claim 4, wherein The second information includes a second indication parameter, and a value of the second carrier frequency deviation corresponds to the second indication parameter.

8. The method according to any one of claims 1 to 2, 5, and 7, characterized in that, Further comprising: Receiving third information from the base station indicating a third carrier frequency deviation, where the third carrier frequency deviation is a carrier frequency deviation between an actual carrier frequency of the first cell and an acquired carrier frequency of the first cell; Obtaining the actual carrier frequency of the first cell according to the third information.

9. The method according to claim 8, wherein, The carrier frequency of the first cell includes an uplink carrier frequency of the first cell and a downlink carrier frequency of the first cell.

10. The method according to claim 9, wherein The third information includes a third indication parameter, and a value of the third carrier frequency deviation corresponds to the third indication parameter.

11. The method according to any one of claims 1 to 2, 5, 7, 9 to 10, characterized in that, The acquired downlink carrier frequency of the second cell is an integer multiple of 100 kHz closest to the actual downlink carrier frequency of the second cell; and / or The acquired uplink carrier frequency of the second cell is an integer multiple of 100 kHz closest to the actual uplink carrier frequency of the second cell.

12. The method according to any one of claims 1 to 2, 5, 7, 9 to 10, characterized in that, The first cell and the second cell are NB-IoT cells.

13. A communication method, characterized in that, Comprising: Determining first information indicating a first carrier frequency deviation, where the first carrier frequency deviation is a carrier frequency deviation between an actual downlink carrier frequency of a second cell and a downlink carrier frequency of the second cell acquired by a terminal; Sending the first information to the terminal through a first cell; Wherein, the second cell is a different-frequency cell of the first cell.

14. The method according to claim 13, characterized in that, The downlink carrier frequency of the second cell is used for cell reselection or cell handover.

15. The method according to claim 13 or 14, characterized in that Sending the first information to the terminal through a broadcast message of the first cell.

16. The method according to claim 13 or 14, characterized in that, Further comprising: Determining second information indicating a second carrier frequency deviation, where the second carrier frequency deviation is information on a carrier frequency deviation between an actual uplink carrier frequency of a second cell and an uplink carrier frequency of the second cell acquired by the terminal; Sending the second information to the terminal through the second cell.

17. The method according to claim 16, wherein Sending the second information to the terminal through a broadcast message or a dedicated message of the second cell.

18. The method according to any one of claims 13 to 14 and 17, characterized in that The first information includes a first indication parameter, and a value of the first carrier frequency deviation corresponds to the first indication parameter.

19. The method according to claim 16, wherein The second information includes a second indication parameter, and the value of the second carrier frequency deviation corresponds to the second indication parameter.

20. The method according to any one of claims 13 to 14, 17, and 19, characterized in that, Further included are: Determining third information indicating a third carrier frequency deviation, where the third carrier frequency deviation is the carrier frequency deviation between the actual first cell carrier frequency and the first cell carrier frequency obtained by the terminal; Sending the third information to the terminal.

21. The method according to claim 20, wherein The first cell carrier frequency includes a first cell uplink carrier frequency and a first cell downlink carrier frequency.

22. The method according to claim 21, wherein, The third information includes a third indication parameter, and the value of the third carrier frequency deviation corresponds to the third indication parameter.

23. The method according to any one of claims 13 to 14, 17, 19, 21 to 22, characterized in that, The second cell downlink carrier frequency obtained by the terminal is an integer multiple of 100 kHz closest to the actual second cell downlink carrier frequency; and / or The second cell uplink carrier frequency obtained by the terminal is an integer multiple of 100 kHz closest to the actual second cell uplink carrier frequency.

24. The method according to any one of claims 13 to 14, 17, 19, 21 to 22, characterized in that, The first cell and the second cell are NB-IoT cells.

25. A communication method, characterized in that, Included are: Receiving fourth information indicating a fourth carrier frequency deviation from a base station, where the fourth carrier frequency deviation is the carrier frequency deviation between the actual cell uplink carrier frequency and the obtained cell uplink carrier frequency, and the actual cell uplink carrier frequency is used for random access, and the cell is an NB-IoT cell; Obtaining the actual cell uplink carrier frequency according to the fourth information.

26. The method according to claim 25, wherein Receiving the fourth information through a broadcast message or a dedicated message.

27. The method according to claim 26, wherein The fourth information includes a fourth indication parameter, and the value of the fourth carrier frequency deviation corresponds to the fourth indication parameter.

28. A communication method, characterized in that, Included are: Determining fourth information indicating a fourth carrier frequency deviation, where the fourth carrier frequency deviation is the carrier frequency deviation between the actual cell uplink carrier frequency and the cell uplink carrier frequency obtained by the terminal, and the actual cell uplink carrier frequency is used for random access, and the cell is an NB-IoT cell; Sending the fourth information to the terminal.

29. The communication method according to claim 28, wherein Sending the fourth information to the terminal through a broadcast message or a dedicated message.

30. The method according to claim 28 or 29, characterized in that The fourth information includes a fourth indication parameter, and the value of the fourth carrier frequency deviation corresponds to the fourth indication parameter.

31. A communication device, characterized in that, Including a unit or device for performing any of the methods described in claims 1 to 12, 25 to 27.

32. A communication device, characterized in that, Including a unit or device for performing any of the methods described in claims 13 to 24, 28 to 30.

33. A communication device, characterized in that, Included are: A processor and a memory; Wherein, the memory is used for storing programs; The processor is used for executing the programs stored in the memory to implement any of the methods described in claims 1 to 12, 25 to 27.

34. A communication device, characterized in that, Included are: A processor and a memory; Wherein, the memory is used for storing programs; The processor is used for executing the programs stored in the memory to implement any of the methods described in claims 13 to 24, 28 to 30.

35. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a program, and when the program runs on a computer, it causes the computer to execute any of the methods described in claims 1 to 12, 25 to 27, 13 to 24, 28 to 30.

36. A computer program product, characterized in that, The computer program product stores a program which, when run on a computer, causes the computer to execute the method according to any one of claims 1 to 12, 25 to 27, 13 to 24, 28 to 30.

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