Method and device for expanding cyclic prefix, terminal and network equipment

Abstract

The invention provides a method and device for expanding a cyclic prefix, a terminal and network equipment. The method comprises the following steps: a terminal receives related information of an extended CP sent by a network device, and / or information of a frequency domain reserved resource of a first OFDM symbol; wherein the related information of the extended CP is used for indicating a target OFDM symbol using the extended CP and an extended increment of the CP; the first OFDM symbol is adjacent to the target OFDM symbol; and the terminal executes data transmission according to the related information of the extended CP and / or the information of the frequency domain reservation resource of the first OFDM symbol. According to the scheme, the CP extension effect is achieved under the condition that the frame structure of the physical layer is not changed, the equipment implementation cost is low, terminal services of an old version can be compatible, and air interface resources are saved.

Description

Technical Field

[0001] The present application relates to the field of communication technology, and in particular to a method, apparatus, terminal and network equipment for extending a cyclic prefix. Background Art

[0002] In future broadcast and multicast services, it is necessary to support higher-speed video streaming services, such as high-definition television and augmented reality (AR) / virtual reality (VR) images. The characteristics of these services are that they require higher data transmission rates.

[0003] Single Frequency Network (SFN) technology is an effective way to improve the transmission efficiency of broadcast and multicast services, and is adopted in the Multicast / Broadcast Service (MBS) of Long Term Evolution (LTE). However, SFN technology requires the support of long cyclic prefix (CP), and the existing New Radio (NR) frame structure parameters do not support the frame structure of long CP. The introduction of long CP will cause major changes to the physical layer, thereby increasing the complexity of product manufacturing. Summary of the invention

[0004] The purpose of the present application is to provide a method, apparatus, terminal and network equipment for extending a cyclic prefix, which solves the problem of increasing the complexity of product manufacturing by introducing a long CP in SFN.

[0005] An embodiment of the present application provides a method for extending a cyclic prefix, including:

[0006] The terminal receives relevant information of the extended cyclic prefix CP and / or information of the frequency domain reserved resources of the first OFDM symbol sent by the network device;

[0007] The relevant information of the extended CP is used to indicate a target OFDM symbol using the extended CP and an extended increment of the CP; the first OFDM symbol is adjacent to the target OFDM symbol;

[0008] The terminal performs data transmission according to the relevant information of the extended CP and / or the information of the frequency domain reserved resources of the first OFDM symbol.

[0009] Optionally, the relevant information of the extended CP includes at least one of the following:

[0010] Information indicating a target OFDM symbol using an extended CP;

[0011] Expansion increment of CP;

[0012] The extended CP length.

[0013] Optionally, the receiving network device sends relevant information of the extended cyclic prefix CP and / or information of the frequency domain reserved resources of the first OFDM symbol, including:

[0014] A high-layer signaling and / or a scheduling signaling sent by a network device is received, where the high-layer signaling and / or the scheduling signaling carries relevant information of the extended CP and / or information of frequency domain reserved resources of the first OFDM symbol.

[0015] Optionally, performing data transmission according to information of frequency domain reserved resources of the first OFDM symbol includes:

[0016] According to the information of the frequency domain reserved resources of the first OFDM symbol, it is determined that the frequency domain reserved resources are not used for downlink transmission or uplink transmission.

[0017] Optionally, performing data transmission according to relevant information of the extended CP includes:

[0018] According to the extended increment of the CP, a starting position for receiving the target OFDM symbol is adjusted.

[0019] Optionally, the starting position for receiving the target OFDM symbol is: a position that is M time domain positions later than the receiving starting position determined by a conventional CP;

[0020] Where M is the expansion increment of CP.

[0021] An embodiment of the present application provides a method for extending a cyclic prefix, including:

[0022] The network device sends relevant information of the extended cyclic prefix CP and / or information of the frequency domain reserved resources of the first OFDM symbol to the terminal;

[0023] The relevant information of the extended CP is used to indicate the target OFDM symbol using the extended CP and the extended increment of the CP; and the first OFDM symbol is adjacent to the target OFDM symbol.

[0024] Optionally, the relevant information of the extended CP includes at least one of the following:

[0025] Information indicating a target OFDM symbol using an extended CP;

[0026] Expansion increment of CP;

[0027] The extended CP length.

[0028] Optionally, the sending the relevant information of the extended cyclic prefix CP and / or the information of the frequency domain reserved resources of the first OFDM symbol to the terminal includes:

[0029] A high-layer signaling and / or a scheduling signaling is sent to the terminal, wherein the high-layer signaling and / or the scheduling signaling carries relevant information of the extended CP and / or information of frequency domain reserved resources of the first OFDM symbol.

[0030] Optionally, the method further includes:

[0031] Mapping the data to be sent to the frequency domain of the OFDM symbol to be sent;

[0032] For the first OFDM symbol, determining a position of the frequency domain reserved resource and a value of the frequency domain reserved resource;

[0033] Performing transformation to generate OFDM symbols to be transmitted;

[0034] Adding CPs to the OFDM symbol according to a conventional number of CPs;

[0035] The OFDM symbol is sent to a terminal.

[0036] Optionally, the first OFDM symbol is an adjacent symbol after the time domain position of the target OFDM symbol, and the values ​​of the M first time domain positions of the first OFDM symbol are the same as the values ​​of the first M time domain positions of the target OFDM symbol;

[0037] or,

[0038] The first OFDM symbol is an adjacent symbol before the time domain position of the target OFDM symbol, and the values ​​of the last M time domain positions of the first OFDM symbol are the same as the values ​​of the M second time domain positions of the target OFDM symbol;

[0039] Where M is the expansion increment of CP.

[0040] Optionally, the M first time domain positions include one of the following:

[0041] The first M time domain positions of the first OFDM symbol after adding the CP according to the conventional CP number;

[0042] When M is less than or equal to A, the M first time domain positions include: a time domain position of first data and subsequent M-1 time domain positions, and the first data is: data whose sequence number is the difference between the total length of the data sequence and A;

[0043] When M is greater than A, the 1st to Ath time domain positions in M ​​are: the time domain position of the first data and the subsequent A-1 time domain positions, the first data being: data whose sequence number is the difference between the total length of the data sequence and A; the A+1th to Mth time domain positions in M ​​are: the first MA time domain positions;

[0044] Where A is the number of sample points of the conventional CP.

[0045] Optionally, the M second time domain positions include:

[0046] The difference between the total length of the data sequence and the total length of the extended CP and the time domain position of the subsequent M-1 data.

[0047] Optionally, the method further includes:

[0048] Select M1 frequency domain reserved resource positions from the N frequency domain positions, where M1 is greater than or equal to 0;

[0049] According to the M known data and the transformation formula, one or more sets of numerical solutions are determined, each set of numerical solutions corresponds to a resource location combination;

[0050] If the numerical solution is a group, determining the group of numerical solutions as the numerical value of the frequency domain reserved resources; if the numerical solution is multiple groups, determining a group of numerical solutions that meets the first condition in the multiple groups of numerical solutions as the numerical value of the frequency domain reserved resources;

[0051] Wherein, M is the extended increment of CP, and the M known data are the values ​​of the M time domain positions where the first OFDM symbol is the same as the target OFDM symbol.

[0052] Optionally, the first condition includes at least one of the following:

[0053] The moduli of all the values ​​in a set of numerical solutions are smaller than the first threshold;

[0054] The average value of the moduli of all numerical values ​​in a set of numerical solutions is less than a second threshold.

[0055] Optionally, the distribution of the M1 frequency domain reserved resources includes at least one of the following situations:

[0056] The M1 frequency domain reserved resources are distributed in the transmittable bandwidth;

[0057] The M1 frequency domain reserved resources are distributed in the protection bandwidth, and the signal power of the M1 frequency domain reserved resources is less than a third threshold;

[0058] The M1 frequency domain reserved resources are distributed outside the bandwidth, and signal powers of the M1 frequency domain reserved resources are less than a fourth threshold.

[0059] Optionally, the method further includes:

[0060] Determining an expansion increment of the CP, wherein the expansion increment of the CP is an increment relative to the number of regular CPs;

[0061] The relevant information of the extended CP is determined according to the extended increment of the CP.

[0062] Optionally, the frequency domain reserved resources of the first OFDM symbol are not used for downlink transmission or uplink transmission.

[0063] An embodiment of the present application provides a terminal, including: a memory, a transceiver, and a processor:

[0064] A memory for storing a computer program; a transceiver for receiving and sending data under the control of the processor; and a processor for reading the computer program in the memory and performing the following operations:

[0065] Receiving information related to the extended CP and / or information on frequency domain reserved resources of the first OFDM symbol sent by the network device;

[0066] The relevant information of the extended CP is used to indicate a target OFDM symbol using the extended CP and an extended increment of the CP; the first OFDM symbol is adjacent to the target OFDM symbol;

[0067] Data transmission is performed according to the relevant information of the extended CP and / or the information of the frequency domain reserved resources of the first OFDM symbol.

[0068] Optionally, the relevant information of the extended CP includes at least one of the following:

[0069] Information indicating a target OFDM symbol using an extended CP;

[0070] Expansion increment of CP;

[0071] The extended CP length.

[0072] Optionally, the processor is configured to read the computer program in the memory and perform the following operations:

[0073] A high-layer signaling and / or a scheduling signaling sent by a network device is received, where the high-layer signaling and / or the scheduling signaling carries relevant information of the extended CP and / or information of frequency domain reserved resources of the first OFDM symbol.

[0074] Optionally, the processor is configured to read the computer program in the memory and perform the following operations:

[0075] According to the information of the frequency domain reserved resources of the first OFDM symbol, it is determined that the frequency domain reserved resources are not used for downlink transmission or uplink transmission.

[0076] Optionally, the processor is configured to read the computer program in the memory and perform the following operations:

[0077] According to the extended increment of the CP, a starting position for receiving the target OFDM symbol is adjusted.

[0078] Optionally, the starting position for receiving the target OFDM symbol is: a position that is M time domain positions later than the receiving starting position determined by a conventional CP;

[0079] Where M is the expansion increment of CP.

[0080] An embodiment of the present application provides a network device, including: a memory, a transceiver, and a processor:

[0081] A memory for storing a computer program; a transceiver for receiving and sending data under the control of the processor; and a processor for reading the computer program in the memory and performing the following operations:

[0082] Sending relevant information of the extended cyclic prefix CP and / or information of the frequency domain reserved resources of the first OFDM symbol to the terminal;

[0083] The relevant information of the extended CP is used to indicate the target OFDM symbol using the extended CP and the extended increment of the CP; and the first OFDM symbol is adjacent to the target OFDM symbol.

[0084] Optionally, the relevant information of the extended CP includes at least one of the following:

[0085] Information indicating a target OFDM symbol using an extended CP;

[0086] Expansion increment of CP;

[0087] The extended CP length.

[0088] Optionally, the processor is configured to read the computer program in the memory and perform the following operations:

[0089] A high-layer signaling and / or a scheduling signaling is sent to the terminal, wherein the high-layer signaling and / or the scheduling signaling carries relevant information of the extended CP and / or information of frequency domain reserved resources of the first OFDM symbol.

[0090] Optionally, the processor is configured to read the computer program in the memory and perform the following operations:

[0091] Mapping the data to be sent to the frequency domain of the OFDM symbol to be sent;

[0092] For the first OFDM symbol, determining a position of the frequency domain reserved resource and a value of the frequency domain reserved resource;

[0093] Performing transformation to generate OFDM symbols to be transmitted;

[0094] Adding CPs to the OFDM symbol according to a conventional number of CPs;

[0095] The OFDM symbol is sent to a terminal.

[0096] Optionally, the first OFDM symbol is an adjacent symbol after the time domain position of the target OFDM symbol, and the values ​​of the M first time domain positions of the first OFDM symbol are the same as the values ​​of the first M time domain positions of the target OFDM symbol;

[0097] or,

[0098] The first OFDM symbol is an adjacent symbol before the time domain position of the target OFDM symbol, and the values ​​of the last M time domain positions of the first OFDM symbol are the same as the values ​​of the M second time domain positions of the target OFDM symbol;

[0099] Where M is the expansion increment of CP.

[0100] Optionally, the M first time domain positions include one of the following:

[0101] The first M time domain positions of the first OFDM symbol after adding the CP according to the conventional CP number;

[0102] When M is less than or equal to A, the M first time domain positions include: a time domain position of first data and subsequent M-1 time domain positions, and the first data is: data whose sequence number is the difference between the total length of the data sequence and A;

[0103] When M is greater than A, the 1st to Ath time domain positions in M ​​are: the time domain position of the first data and the subsequent A-1 time domain positions, the first data being: data whose sequence number is the difference between the total length of the data sequence and A; the A+1th to Mth time domain positions in M ​​are: the first MA time domain positions;

[0104] Where A is the number of sample points of the conventional CP.

[0105] Optionally, the M second time domain positions include:

[0106] The difference between the total length of the data sequence and the total length of the extended CP and the time domain position of the subsequent M-1 data.

[0107] Optionally, the processor is configured to read the computer program in the memory and perform the following operations:

[0108] Select M1 frequency domain reserved resource positions from the N frequency domain positions, where M1 is greater than or equal to 0;

[0109] According to the M known data and the transformation formula, one or more sets of numerical solutions are determined, each set of numerical solutions corresponds to a resource location combination;

[0110] If the numerical solution is a group, determining the group of numerical solutions as the numerical value of the frequency domain reserved resources; if the numerical solution is multiple groups, determining a group of numerical solutions that meets the first condition in the multiple groups of numerical solutions as the numerical value of the frequency domain reserved resources;

[0111] Wherein, M is the extended increment of CP, and the M known data are the values ​​of the M time domain positions where the first OFDM symbol is the same as the target OFDM symbol.

[0112] Optionally, the first condition includes at least one of the following:

[0113] The moduli of all the values ​​in a set of numerical solutions are smaller than the first threshold;

[0114] The average value of the moduli of all numerical values ​​in a set of numerical solutions is less than a second threshold.

[0115] Optionally, the distribution of the M1 frequency domain reserved resources includes at least one of the following situations:

[0116] The M1 frequency domain reserved resources are distributed in the transmittable bandwidth;

[0117] The M1 frequency domain reserved resources are distributed in the protection bandwidth, and the signal power of the M1 frequency domain reserved resources is less than a third threshold;

[0118] The M1 frequency domain reserved resources are distributed outside the bandwidth, and signal powers of the M1 frequency domain reserved resources are less than a fourth threshold.

[0119] Optionally, the processor is configured to read the computer program in the memory and perform the following operations:

[0120] Determining an expansion increment of the CP, wherein the expansion increment of the CP is an increment relative to the number of regular CPs;

[0121] The relevant information of the extended CP is determined according to the extended increment of the CP.

[0122] Optionally, the frequency domain reserved resources of the first OFDM symbol are not used for downlink transmission or uplink transmission.

[0123] An embodiment of the present application provides a device for extending a cyclic prefix, which is applied to a terminal, including:

[0124] A first receiving unit, configured to receive relevant information of an extended cyclic prefix CP sent by a network device, and / or information of a frequency domain reserved resource of a first OFDM symbol;

[0125] The relevant information of the extended CP is used to indicate a target OFDM symbol using the extended CP and an extended increment of the CP; the first OFDM symbol is adjacent to the target OFDM symbol;

[0126] The transmission unit is used to perform data transmission according to the relevant information of the extended CP and / or the information of the frequency domain reserved resources of the first OFDM symbol.

[0127] An embodiment of the present application provides a device for extending a cyclic prefix, which is applied to a network device, including:

[0128] A first sending unit, configured to send relevant information of an extended cyclic prefix CP and / or information of a frequency domain reserved resource of a first OFDM symbol to a terminal;

[0129] The relevant information of the extended CP is used to indicate the target OFDM symbol using the extended CP and the extended increment of the CP; and the first OFDM symbol is adjacent to the target OFDM symbol.

[0130] An embodiment of the present application provides a processor-readable storage medium on which a computer program is stored. When the computer program is executed by a processor, the steps of the above-mentioned method for extending the cyclic prefix are implemented.

[0131] The beneficial effects of the above technical solution of the present application are:

[0132] In an embodiment of the present application, a terminal receives relevant information of an extended CP sent by a network device, thereby determining a target OFDM symbol that needs CP extension and an extended increment of the CP; based on the extended increment of the CP, the terminal can adjust the starting position of the received target OFDM symbol, and by adjusting the starting position of the received target OFDM symbol, the effect of extending the CP can be achieved without changing the physical layer frame structure. The terminal can determine the unavailable position in data transmission based on the information of the frequency domain reserved resources of the adjacent symbols of the target OFDM symbol sent by the network device, thereby improving the data reception efficiency; the terminal can also obtain the uplink OFDM symbol to be sent based on the information of the frequency domain reserved resources, thereby achieving the effect of extending the CP without changing the physical layer frame structure. This solution achieves the effect of extending the CP without changing the physical layer frame structure, the device implementation cost is low, and it is compatible with the terminal services of old versions, and can save air interface resources. BRIEF DESCRIPTION OF THE DRAWINGS

[0133] Figure 1 A schematic diagram showing a basic OFDM process;

[0134] Figure 2 A schematic diagram showing SFN technology at the cell level;

[0135] Figure 3 A flowchart of a method for extending a cyclic prefix according to an embodiment of the present application is shown;

[0136] Figure 4 One of the schematic diagrams showing the extended CP of an embodiment of the present application;

[0137] Figure 5 One of the multipath delay difference schematic diagrams showing an embodiment of the present application;

[0138] Figure 6 A second schematic diagram showing multipath delay difference according to an embodiment of the present application;

[0139] Figure 7 A second schematic diagram showing an extended CP according to an embodiment of the present application;

[0140] Figure 8 A third schematic diagram showing an extended CP according to an embodiment of the present application;

[0141] Fig. 9 A third schematic diagram showing multipath delay difference according to an embodiment of the present application;

[0142] Fig.10 A fourth schematic diagram showing multipath delay difference in an embodiment of the present application;

[0143] Fig.11 A fourth schematic diagram showing an extended CP according to an embodiment of the present application;

[0144] Fig.12 A fifth schematic diagram showing an extended CP according to an embodiment of the present application;

[0145] Fig.13 A schematic diagram showing the numerical relationship between adjacent symbols in an embodiment of the present application;

[0146] Fig.14 A schematic diagram showing a protection bandwidth / out-of-band frequency according to an embodiment of the present application;

[0147] Fig.15 One of the schematic diagrams showing the effect of performing CP expansion according to an embodiment of the present application;

[0148] Fig.16 A sixth schematic diagram showing an extended CP according to an embodiment of the present application;

[0149] Fig.17A seventh schematic diagram showing an extended CP according to an embodiment of the present application;

[0150] Fig.18 An eighth schematic diagram showing an extended CP according to an embodiment of the present application;

[0151] Fig.19 A ninth schematic diagram showing an extended CP according to an embodiment of the present application;

[0152] Fig. 20 A tenth schematic diagram showing an extended CP according to an embodiment of the present application;

[0153] Fig.21 A second schematic diagram showing the effect of performing CP expansion according to an embodiment of the present application;

[0154] Fig. 22 A second flowchart of a method for extending a cyclic prefix according to an embodiment of the present application is shown;

[0155] Fig.23 A schematic diagram showing a structure of an apparatus for extending a cyclic prefix according to an embodiment of the present application;

[0156] Fig.24 A second structural diagram showing an apparatus for extending a cyclic prefix according to an embodiment of the present application;

[0157] Fig.25 A schematic diagram showing the structure of a terminal according to an embodiment of the present application;

[0158] Fig.26 A schematic diagram showing the structure of a network device according to an embodiment of the present application. DETAILED DESCRIPTION

[0159] In order to make the technical problems, technical solutions and advantages to be solved by the application clearer, the following will be described in detail in conjunction with the accompanying drawings and specific embodiments. In the following description, specific details such as specific configurations and components are provided only to help fully understand the embodiments of the application. Therefore, it should be clear to those skilled in the art that various changes and modifications can be made to the embodiments described herein without departing from the scope and spirit of the application. In addition, for clarity and brevity, the description of known functions and structures has been omitted.

[0160] It should be understood that the references to "one embodiment" or "an embodiment" throughout the specification mean that the specific features, structures, or characteristics associated with the embodiment are included in at least one embodiment of the present application. Therefore, the references to "in one embodiment" or "in an embodiment" appearing throughout the specification do not necessarily refer to the same embodiment. In addition, these specific features, structures, or characteristics may be combined in any suitable manner in one or more embodiments.

[0161] In the various embodiments of the present application, it should be understood that the size of the serial numbers of the following processes does not mean the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present application.

[0162] In the embodiments of the present application, the term "and / or" describes the association relationship of the associated objects, indicating that three relationships may exist. For example, A and / or B may represent: A exists alone, A and B exist at the same time, and B exists alone. The character " / " generally indicates that the associated objects before and after are in an "or" relationship.

[0163] In the embodiments of the present application, the term "plurality" refers to two or more than two, and other quantifiers are similar.

[0164] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0165] When describing the embodiments of the present application, some concepts used in the following description are first explained.

[0166] 1. Orthogonal frequency division multiplex (OFDM) processing

[0167] The basic process of OFDM transmitter is as follows Figure 1 As shown, an Inverse Fast Fourier Transform (IFFT) is performed on the N points, and a parallel / serial conversion is performed on the output of the IFFT, and then a process of adding a CP is performed.

[0168] The IFFT transformation can be expressed by the following formula:

[0169]

[0170] The input x sequence of IFFT is frequency domain data, and the output x sequence of IFFT is time domain data.

[0171] in:

[0172] X(0) to X(g-1) are guard bands in the frequency domain, and the transmitter usually sets these REs to 0. g is the number of resource elements (REs) in the guard band.

[0173] X(g) to X(NRE+g-1) are frequency domain data information, which are RE units that can carry data in the OFDM system. NRE is the length set by the system.

[0174] X(NRE+g) to X(N-1) are guard bands in the frequency domain. Usually, the transmitter sets these REs to 0. g is the number of guard band REs.

[0175] 2. NR frame structure

[0176] Frame structure: A wireless frame is 10ms long and contains 10 sub-frames. Each sub-frame is 1ms long. Each sub-frame contains several time slots (different SCSs contain different number of time slots), and each time slot contains 14 symbols. See Table 1.

[0177] Table 1: Frame structure parameters

[0178]

[0179] Table 1 describes the number of time slots included in a 10ms radio frame and the number of time slots included in each subframe under different SCS conditions. For example, when μ=4, each subframe includes 16 time slots, each time slot includes 14 symbols, that is, each subframe includes 16*14=224 symbols.

[0180] Symbol length and CP: The symbol length and CP length when the subcarrier spacing (SCS) remains unchanged are as follows:

[0181]

[0182]

[0183] Where μ is the subcarrier width configuration and l is the number of symbols.

[0184] 3. Cell-level SFN technology

[0185] SFN technology is that adjacent cells / base stations send the same signal. When the same signal sent by different cells reaches the UE at the edge of the cell, the power of the received signal is the superposition of the signals of each cell. In traditional non-SFN technology, the signals from other cells are interference, which makes SFN technology have a strong advantage in sending broadcast signals and greatly improves the receiving performance of UE at the edge of the cell. Figure 2 Schematic diagram of SFN technology at the cell level.

[0186] like Figure 2The cell-level SFN technology gain shown in the figure is equivalent to not using SFN technology when the SFN cell is 1. Assuming that the signal power received by the UE in the edge cell is 1, when the SFN cell is 3, the received signal power is 3, when the number of cells participating in SFN is 12, the received signal power is 4.42. When the number of cells participating in SFN is 27, the received signal power is 4.94. SFN technology can increase the signal power of UE at the cell edge, improve the spectrum utilization rate at the cell edge, and thus improve user satisfaction.

[0187] The embodiments of the present application provide a method, apparatus, terminal and network device for extending a cyclic prefix, so as to solve the problem of increasing product complexity by introducing a long CP in SFN.

[0188] Among them, the method and the device are based on the same application concept. Since the method and the device solve the problem in a similar principle, the implementation of the device and the method can refer to each other, and the repeated parts will not be repeated.

[0189] like Figure 3 As shown, an embodiment of the present application provides a method for extending a cyclic prefix, which is applied to a terminal and specifically includes the following steps:

[0190] Step 301: The terminal receives information related to an extended cyclic prefix CP and / or information on frequency domain reserved resources of a first OFDM symbol sent by a network device;

[0191] The relevant information of the extended CP is used to indicate a target OFDM symbol using the extended CP and an extended increment of the CP; the first OFDM symbol is adjacent to the target OFDM symbol;

[0192] Step 302: The terminal performs data transmission according to the relevant information of the extended CP and / or the information of the frequency domain reserved resources of the first OFDM symbol.

[0193] In this embodiment, the network device may send the relevant information of the extended CP to the terminal, indicating the target OFDM symbol and the extended increment of the CP that the terminal needs to perform CP extension. The target OFDM symbol may be one or more, and the extended increment of the CP is the increment relative to the number of CPs before extension. The terminal adjusts the starting position of the received target OFDM symbol according to the relevant information of the extended CP, thereby achieving the purpose of extending the CP of the target OFDM symbol.

[0194] Optionally, the network device may also send to the terminal information about the frequency domain reserved resources of the adjacent symbols (i.e., the first OFDM symbol) of the target OFDM symbol that needs to extend the CP. The frequency domain reserved resources are the reserved resources before the first OFDM symbol is transformed, and the transformation may refer to an inverse discrete Fourier transform (IDFT, or IFFT). The information about the frequency domain reserved resources may include: the position of the frequency domain reserved resources and the value of the position. The network device can achieve the effect of CP extension for the target OFDM symbol by setting the value of the frequency domain reserved resources.

[0195] In an embodiment of the present application, a terminal receives relevant information of an extended CP sent by a network device, thereby determining a target OFDM symbol that needs CP extension and an extended increment of the CP; based on the extended increment of the CP, the terminal can adjust the starting position of the received target OFDM symbol, and by adjusting the starting position of the received target OFDM symbol, the effect of extending the CP can be achieved without changing the physical layer frame structure. The terminal can determine the unavailable position in data transmission based on the information of the frequency domain reserved resources of the adjacent symbols of the target OFDM symbol sent by the network device, thereby improving the data reception efficiency; the terminal can also obtain the uplink OFDM symbol to be sent based on the information of the frequency domain reserved resources, thereby achieving the effect of extending the CP without changing the physical layer frame structure. This solution achieves the effect of extending the CP without changing the physical layer frame structure, the device implementation cost is low, and it is compatible with the terminal services of old versions, and can save air interface resources.

[0196] It should be noted that: the downlink data symbol sending process described in this technical solution, that is, the terminal is the receiving end of the data symbol; the network device is the sending end of the data symbol. The relevant technology can also be applied to the transmission process of uplink data sending. At this time, the terminal is the sending end, the network device is the receiving end, and the information configuration and indication are performed by the network device. That is: for the transmission of uplink data, it is still the network device that sends the relevant information of the extended CP to the terminal, and / or the information of the frequency domain reserved resources of the first OFDM symbol. The terminal performs the data sending process based on the received information, and the data sending process may include: data mapping, transformation, adding CP, sending symbols and other processes. The network device receives the uplink data sent by the terminal.

[0197] Optionally, the terminal performs data transmission according to relevant information of the extended CP and / or information of frequency domain reserved resources of the first OFDM symbol, which may include: performing uplink data transmission or downlink data transmission according to relevant information of the extended CP and / or information of frequency domain reserved resources of the first OFDM symbol.

[0198] The performing of uplink data transmission according to the information related to the extended CP and / or the information of the frequency domain reserved resources of the first OFDM symbol may include: generating an OFDM symbol to be sent according to the information related to the extended CP and / or the information of the frequency domain reserved resources of the first OFDM symbol; and sending the OFDM symbol to a network device. The OFDM symbol generated in this way can achieve the effect of equivalently extending the CP without changing the frame structure.

[0199] The performing of downlink data transmission according to the relevant information of the extended CP and / or the information of the frequency domain reserved resources of the first OFDM symbol may include: adjusting the starting position of receiving the target OFDM symbol according to the relevant information of the extended CP. In this way, by adjusting the starting position of receiving the target OFDM symbol, the effect of equivalently extending the CP can be achieved without changing the frame structure.

[0200] Optionally, the relevant information of the extended CP includes at least one of the following:

[0201] 1) Information indicating the target OFDM symbol using the extended CP; this information may indicate which one or more symbols need to be CP extended.

[0202] 2) Extension increment of CP: The extension increment of CP is an increment relative to the CP length before extension, and its unit can be microseconds (or milliseconds), or sampling points, or the time unit of IFFT sample points.

[0203] Optionally, the network device may determine an expansion increment of the CP based on service transmission quality requirements and spacing information of deployed network devices.

[0204] 3) Length of the extended CP: The network device may also directly indicate the length of the extended CP, and the CP extension amount may be obtained by calculation.

[0205] In this embodiment, the terminal receives the configuration or indication information of the network device, and then determines the CP time domain extension increment. The network device can directly indicate the value of the extension increment, or can indicate the CP length after extension. If the CP length after extension is indicated, the terminal can determine the extension increment according to the CP length of the current symbol and the CP length after extension.

[0206] Assume that the extended increment of CP is represented by M, and the unit of M is the same as the time unit of the IFFT sample point.

[0207] For example, assuming the number of IFFT samples is 2048, the value of M is as follows:

[0208] The CP length before extension is 144, and the CP length after extension is 512, so M is equal to 512-144=368.

[0209] The CP length before extension is 160, and the CP length after extension is 512, so M is equal to 512-160=352.

[0210] As an optional embodiment, the receiving network device sends the relevant information of the extended cyclic prefix CP and / or the information of the frequency domain reserved resources of the first OFDM symbol, including:

[0211] A high-layer signaling and / or a scheduling signaling sent by a network device is received, where the high-layer signaling and / or the scheduling signaling carries relevant information of the extended CP and / or information of frequency domain reserved resources of the first OFDM symbol.

[0212] In this embodiment, the network device sends the relevant information of the extended CP and / or the frequency domain reserved resource information of the first OFDM symbol to the terminal through high-level signaling and / or scheduling signaling. The scheduling information may be dynamic scheduling signaling. For example, the CP extension amount may be indicated by high-level information or by dynamic scheduling signaling, and the indicated value may be an extension increment M or the length of the extended CP.

[0213] For example, the network device configures one or more OFDM symbols of extended CP through high-level signaling, and the OFDM symbols that need to be extended by CP may be: all downlink symbols (time slots) on the serving cell, or part of the downlink symbols (time slots). Alternatively, the network device indicates one or more OFDM symbols of extended CP through scheduling signaling, and the OFDM symbols that need to be extended by CP may be: all symbols or part of the scheduled symbols.

[0214] When the network device sends the information of the frequency domain reserved resources of the first OFDM symbol to the terminal, the network device may indicate the information of the M1 frequency domain reserved resources of the first OFDM symbol in the OFDM symbol to the terminal. The network device sends the OFDM symbol to the terminal after processes such as CP addition.

[0215] For the target OFDM symbol of the extended CP, the terminal can determine the timing information of the target OFDM symbol according to the extended increment of the CP, that is, the starting position of the receiving data window for performing discrete Fourier transform (DFT). Specifically: Assuming that the synchronization moment determined by the UE according to the synchronization signal is t0, the synchronization moment of receiving the target OFDM symbol is delayed by M time units, that is, t0+t(M); here t(M) refers to converting the M value into the same time dimension as t0.

[0216] Optionally, performing data transmission according to the information of frequency domain reserved resources of the first OFDM symbol includes: determining, according to the information of frequency domain reserved resources of the first OFDM symbol, that the reserved resources are not used for downlink transmission or uplink transmission.

[0217] In this embodiment, the downlink transmission includes but is not limited to: physical downlink shared channel (Physical downlink shared channel, PDSCH), physical downlink control channel (Physical downlink control channel, PDCCH), channel state information reference signal (Channel State Information Reference Signal, CSI-RS), demodulation reference signal (Demodulation Reference Signal, DMRS) transmission.

[0218] It should be noted that, for uplink data transmission, the frequency domain reserved resources before the first OFDM symbol is transformed are not used for uplink transmission.

[0219] The terminal receives the information of the frequency domain reserved resources of the first OFDM symbol sent by the network device, and the information can be used to determine the location and value of M1 frequency domain reserved resources. The information can be a high-level signaling configuration or a dynamic scheduling signaling sent by the network device. For example: the network device configures the information of M1 frequency domain reserved resources through high-level signaling: the information can be applied to all downlink symbols (time slots) on the carrier, or part of the downlink symbols (time slots); or, the network device indicates one or more "M1 frequency domain reserved resource information" through scheduling signaling, which can be all symbols of the scheduled symbols, or part of the symbols.

[0220] The "information of M1 frequency domain reserved resources" is applied to the first OFDM symbol, that is, the adjacent symbol of the target OFDM symbol of the extended CP. On the terminal side, these resources are considered as unavailable resources, that is, the network device is considered not to send data on these resources.

[0221] It should be noted that: each target OFDM symbol of the extended CP corresponds to a first OFDM symbol to which "information of M1 frequency domain reserved resources" is applied. When there are multiple target OFDM symbols of the extended CP, they correspond to multiple first OFDM symbols to which "information of M1 frequency domain reserved resources" is applied.

[0222] For the data to be sent, if it is determined that the target OFDM symbol needs to be CP extended, the network device first determines the position of the M1 frequency domain reserved resources in the first OFDM symbol and the value of the frequency domain reserved resources at the position before performing the IFFT transformation. If the first OFDM symbol is an adjacent symbol after the target OFDM symbol, the "appropriate" position and "appropriate" value of the M1 frequency domain reserved resources of the device are determined so that after the IFFT transformation is performed, the time domain values ​​of the M specific positions in the first OFDM symbol are equal to the first M time domain values ​​of the target OFDM symbol.

[0223] Assume that symbol n is an OFDM symbol that needs to be CP extended, that is, the target OFDM symbol. Symbol n+1 is the first OFDM symbol. For symbol n+1, if after performing IFFT, the values ​​of M specific time domain positions in OFDM symbol n+1 are equal to the first M time domain values ​​of OFDM symbol n, it is equivalent to performing CP extension on symbol n+1.

[0224] It should be noted that the "equality" described in this application is equivalent in the engineering sense. When the difference between two values ​​is less than the error range, they can be considered equal. The specific error range is implemented by the data sending end (for example, the error range is 3% or 5%).

[0225] For the M specific time domain positions in the above symbol n+1, two description methods can be included:

[0226] Description mode 1: adding the first M time domain positions of symbol n+1 after CP extension according to the regular CP number; the regular CP number is the CP number (or length) before CP extension.

[0227] For example, for OFDM symbol n, the first M sequence values ​​in the sequence formed after IFFT transformation are Y0;

[0228] For OFDM symbol n+1, the first M sequence values ​​in the sequence formed after IFFT transformation and adding CP are Y1;

[0229] The above Y0 is equal to Y1.

[0230] Description method 2: Description based on the relationship between M and the number of CP sample points A before expansion.

[0231] Wherein, when M is less than or equal to A, the M first time domain positions include: the time domain position of the first data and the subsequent M-1 time domain positions, and the first data is: data whose sequence number is the difference between the total length of the data sequence and A;

[0232] When M is greater than A, the 1st to Ath time domain positions in M ​​are: the time domain position of the first data and the subsequent A-1 time domain positions, the first data being: data whose sequence number is the difference between the total length of the data sequence and A; the A+1th to Mth time domain positions in M ​​are: the first MA time domain positions;

[0233] Wherein, A is the number of sample points of the regular CP, which may be the length or number of the regular CP.

[0234] For example, for OFDM symbol n: Assuming the frequency domain data length is N, after IDFT transformation, the data OFDM data sequence x is formed. 0 , x 1 ,…x N-2 , x N-1 The first M time domain values ​​are: 0 , v 1 , v 2 ,…v M-1 .

[0235] For OFDM symbol n+1: Assume the frequency domain data length , after IDFT transformation, the data OFDM data sequence x is formed 0 ,x 1 ,…x N-2 ,x N-1 .

[0236] when The following values ​​need to satisfy the conditions:

[0237]

[0238] when hour:

[0239] For m = 0 to m is any value between 0 and M, and the following values ​​need to satisfy the conditions:

[0240]

[0241] for To M-1, the following values ​​need to meet the conditions:

[0242]

[0243] in: Indicates the number of IFFT samples before CP expansion.

[0244] The relationship between the IFFT time domain output samples of OFDM symbol n+1 and OFDM symbol n is as follows: Figure 4As shown, the M time domain values ​​of symbol n+1 after transformation are equal to the first M time domain values ​​of symbol n.

[0245] Optionally, the method for the network device to determine the positions and values ​​of the M1 frequency domain reserved resources of the first OFDM symbol may be as follows:

[0246] Assume that the input frequency domain data is X(n), n=0,1,…N-1;

[0247] Among them, there are M1 frequency domain data {X(k 0 ),X(k 1 ),…X(k M1-1 )} does not transmit any information, that is, any value can be set, and by setting M1 appropriate frequency domain values, the symbol n+1 satisfies the requirement that the above M data sequences are the same after IFFT transformation;

[0248] Here k 0 ,k 1 ,…k M1-1 , is an integer greater than or equal to 0 and less than or equal to N-1 and does not repeat. 0 ,k 1 ,…k M1-1 The number of combinations is: That is, select the combination of M1 elements from N elements.

[0249] The other frequency domains except the M1 frequency domain reserved resources are used to transmit data (ie, the other frequency domain data are fixed values ​​and cannot be changed).

[0250] Among them: the above-mentioned M1 frequency domain positions can be in the communication bandwidth content for data scheduling in the channel bandwidth, or can be placed in the included bandwidth, or placed out of band, but for the protection bandwidth and out-of-band RE, the data value amplitude is constrained by relevant indicators.

[0251] For the values ​​of M1 frequency domain positions: Assume that the frequency domain data {X(k 0 ),X(k 1 ),…X(k M-1 )} is the unknown number to be determined. Since the values ​​of the first M time domain positions in the known symbol n+1 are equal to the values ​​of the first M time domain positions of the symbol n, the time domain sequence x 0 ,x 1 ,…x N-2 ,x N-1 In , there are M known data, according to the following IDFT formula:

[0252]

[0253] When M1 is greater than or equal to M, M linear equations with M1 variables can be listed. That is, by solving M linear equations with M1 variables, at least one set of "numerical solutions" can be obtained.

[0254] Furthermore, due to k 0 ,k 1 ,…k M1-1 The number of combinations is K That is, at least K groups of "numerical solutions" can be obtained.

[0255] Find a set of "appropriate" values ​​from the K sets of "numerical solutions", that is, determine the "appropriate" locations and "appropriate" values ​​of the M1 reserved resources.

[0256] A solution that satisfies a "suitable" value can be defined as one that satisfies at least one of the following conditions:

[0257] The modulus of all M1 values ​​is less than a threshold;

[0258] The average value of the moduli of the M1 values ​​is less than a threshold.

[0259] It should be noted that, for REs on protected bandwidth or out-of-band resources, the above threshold values ​​comply with standard restrictions, that is, the values ​​may be smaller.

[0260] As an optional embodiment, performing data transmission according to relevant information of the extended CP includes: adjusting a starting position for receiving the target OFDM symbol according to an extended increment of the CP.

[0261] Optionally, the starting position for receiving the target OFDM symbol is: a position that is M time domain positions backward from the receiving starting position determined by a conventional CP; wherein M is an extended increment of the CP.

[0262] In this embodiment, when determining the extended increment of the CP of the target OFDM symbol, the terminal adjusts the starting position for receiving the target OFDM symbol to be delayed M time domain positions from the original receiving position. The original receiving position is the receiving starting position determined according to the number of CPs before the extension.

[0263] It should be noted that the above embodiment is described with the terminal as the data receiving end and the network device as the data sending end. In practical applications, the above method of extending CP is also applicable to the transmission of uplink data, that is, the terminal is used as the data sending end and the network device is used as the data receiving end. The process of uplink data transmission is similar to the implementation process of downlink data transmission in the above embodiment. The relevant information of the extended CP and / or the information of the frequency domain reserved resources of the first OFDM symbol are all configured by the network device, but the execution end of the data transmission is different.

[0264] Since the relevant information of the extended CP and / or the information of the frequency domain reserved resources of the first OFDM symbol are configured by the network device, for uplink data transmission, the terminal can perform data transmission based on the information configured by the network device, such as: mapping the data to be sent to the frequency domain of the OFDM symbol to be sent; determining the position of the frequency domain reserved resources and the value of the frequency domain reserved resources for the first OFDM symbol according to the information configured by the network device; performing transformation (such as IFFT or IDFT transformation) to generate the OFDM symbol to be sent; adding CP to the symbol according to the conventional CP number; sending the OFDM symbol to the network device. When receiving uplink data, the network device can adjust the starting position of the received target OFDM symbol based on the extended increment of CP. The starting position of receiving the target OFDM symbol is: the position of M time domain positions extended backward from the receiving starting position determined by the conventional CP. Other similar processes are not repeated here.

[0265] The following takes the downlink data as an example to illustrate the method for implementing the extended CP by the network device and the terminal when the first OFDM symbol is an adjacent symbol after the target OFDM symbol.

[0266] As an example: Assume that an OFDM symbol includes: 2 units of CP length; 8 units of data (ie, the number of IFFT points). Figure 5 As shown in , when the multipath delay difference τ is less than or equal to 2 unit lengths, there is no mutual interference between the multipaths; when the multipath delay difference τ is equal to 3 unit lengths, there is interference between the multipaths. Correspondingly, if the length of the CP is 3 time units, there is no inter-symbol interference, as shown in Figure 6 shown.

[0267] The technical solution of the present application is used to perform CP expansion on symbol 1 and symbol 2, and the expansion increment M=1. Figure 7 As shown. Among them:

[0268] 1) Assume that the IDFT output of symbol 1 is {1, 2, 3, 4, 5, 6, 7, 8}, that is, the first value x(0)=1.

[0269] 2) At a specific frequency domain position of symbol 2, set a "suitable value" so that the IDFT output of symbol 2 is {a, b, c, d, e, f, 1, h}. That is, x(6) = 1 (equal to x(0) of symbol 1). At the same time, x(0) of symbol 2 = a.

[0270] 3) At a specific frequency domain position of symbol 3, set a "suitable value" so that the IDFT output of symbol 3 is {I, J, K, L, M, N, a, P}, i.e. x(6) = a (equal to x(0) of symbol 2).

[0271] The transmitting end (here, the network device) adds CP according to the frame structure parameter of CP=2 to form OFDM transmission data.

[0272] At the receiving end (here, the terminal), the starting position of the DFT input window is set according to CP=3, and the DFT operation (time domain to frequency domain) is performed. Figure 8 It can be seen that when the multipath difference is 3 units:

[0273] For symbol n: the multipath data in the DFT window include: {1,2,3,4,5,6,7,8}. That is, the multipath information is a periodic signal, and there is no inter-symbol interference in the multipath;

[0274] For symbol n+1: the multipath data in the DFT window includes: {1,h,a,b,c,d,e,f}. That is, the multipath information is a periodic signal, and there is no inter-symbol interference in the multipath.

[0275] like Figure 8 As shown, the input window of the DFT of the terminal is delayed backward by M=1 CP sample points relative to the synchronization time (the starting window position of the original DFT of the symbol) obtained according to the synchronization signal.

[0276] As another example: Assume that an OFDM symbol includes: 2 units of CP; 8 units of data (i.e., the number of IFFT points). When the multipath delay difference τ is less than or equal to 2 units, there is no mutual interference between the multipaths; when the multipath delay difference τ is equal to 5 units, there is interference between the multipaths, such as Fig. 9 As shown. Correspondingly, if the length of CP is 5 time units, there is no inter-symbol interference, as shown in Fig.10 shown.

[0277] The following describes how to use this technical solution to perform CP extension on symbol 1 and symbol 2, with the extension amount M=3. Fig.11 shown.

[0278] Assume that the IDFT output of symbol 1 is {1, 2, 3, 4, 5, 6, 7, 8}. That is, the first M = 3 values ​​x(0) = 1, x(1) = 2, x(2) = 3;

[0279] At M1 specific frequency domain positions of symbol 2 (e.g., M1=3), M1 "appropriate values" are set as the values ​​of the reserved resources, so that the IDFT output of symbol 2 is {3, b, c, d, f, g, h, 1, 2}. That is, x(6)=1, x(7)=2, x(0)=3 (equal to x(0), x(1), x(2) of symbol 1). At the same time, x(0)=a, x(1)=b, x(2)=c of symbol 2.

[0280] At M1 specific frequency domain positions of symbol 3 (e.g., M1=4, which can be equal to or different from M1 of symbol 2), set M1 "appropriate values" so that the IDFT output of symbol 3 is {c, j, k, l, m, n, 3, b}. That is, x(6)=3, x(7)=b, x(0)=c (equal to x(0), x(1), x(2) of symbol 2).

[0281] The transmitting end (here, the network device) adds CP according to the frame structure parameter of CP=2 to form OFDM transmission data.

[0282] At the receiving end (here, the terminal), the starting position of the DFT input window is set according to CP=5, and the DFT operation (time domain to frequency domain) is performed. Fig.12 It can be seen that when the multipath difference is 5 units:

[0283] For symbol 1 (DFT-1): the multipath data in the DFT window includes: {1, 2, 3, 4, 5, 6, 7, 8}. That is, the multipath information is a periodic signal, and there is no inter-symbol interference in the multipath.

[0284] For symbol 2 (DFT-2): the multipath data in the DFT window includes: {1, 2, 3, b, c, d, e, f}. That is, the multipath information is a periodic signal, and there is no inter-symbol interference in the multipath.

[0285] Depend on Fig.12 As shown: the input window of the DFT of the terminal is delayed backward by M=3 CP sample points relative to the synchronization time (the starting window position of the original DFT of the symbol) obtained according to the synchronization signal.

[0286] This method does not cause modification of the physical layer structure, can reduce the complexity of protocol formulation, does not increase the implementation cost of the device, and is compatible with old versions of UE.

[0287] In this embodiment, the CP extension effect is achieved without changing the frame structure (i.e., there is no need to modify 1 time slot containing 14 symbols to 1 time slot containing 12 symbols). At the same time, the network device can flexibly set the CP increment M according to actual service requirements to meet the requirements of the distance between different cells in the SFN area. At the same time, it is compatible with the old version of UE to receive broadcast and multicast services, saving air interface resources.

[0288] In an embodiment of the present application, the first OFDM symbol may be an adjacent symbol after the target OFDM symbol of the extended CP, or may be an adjacent symbol before the target OFDM symbol of the extended CP. The following first takes the case where the first OFDM symbol is an adjacent symbol after the target OFDM symbol of the extended CP as an example to illustrate the method of extending the cyclic prefix of the present application.

[0289] As an optional embodiment, it is assumed that the network device only indicates to the terminal the target OFDM symbol that needs to be CP extended, and does not indicate the information of M1 frequency domain reserved resources of the first OFDM symbol.

[0290] Assume that the system parameters are: SCS = 15KHz, FFT point number N = 2048k, original CP length = 144k; the length after CP expansion is 512k, the CP increment M = 512k-144k = 368k, where k is a positive integer (can be 1 or other values). For the sake of ease of description, in this embodiment, it is simplified to: N = 2048, original CP length = 144, the length after CP expansion is 512, and the CP increment M = 512-144 = 368.

[0291] In this example, the network device indicates to the terminal the target OFDM symbol or time slot for CP extension, and related information for the UE to calculate M. For the M1 frequency domain reserved resources of the first OFDM symbol, one of the following methods may be used for indication, that is, the network device does not need to indicate.

[0292] (1) The M1 frequency domain reserved resources are placed outside the scheduled data, that is, the frequency domain reserved resources are not within the frequency domain resources for UE to receive data.

[0293] (2) M1 frequency domain reserved resource information is completed through existing rate matching indication information.

[0294] The process of performing data transmission using the method of extending the cyclic prefix includes:

[0295] Network device side:

[0296] Step 41a: Determine the CP time domain extension increment M.

[0297] The CP extension increment M is relative to the CP length before extension, and its unit can be microseconds (or millimeters), sampling points, or the time unit of IFFT samples. For ease of description, it is assumed here that the unit of M is the same as the time unit of FFT samples, that is, the M CP duration is equivalent to the duration of M points in the N FFT output samples. The related increment M is related to the quality of the transmitted service and the radius of the cell.

[0298] For example, the M value is as follows:

[0299] The CP length before expansion is 144, and the CP length after expansion is 512, so M is equal to 512-144=368;

[0300] The CP length before extension is 160, and the CP length after extension is 512, so M is equal to 512-160=352.

[0301] Step 42a: For symbol n+1, determine the "appropriate" positions and "appropriate" values ​​of the M1 reserved resources so that after executing IFFT, the time domain values ​​of the M specific positions in OFDM symbol n+1 are equal to the first M time domain values ​​of OFDM symbol n.

[0302] Symbol n is an OFDM symbol that needs to be CP extended, and symbol n+1 is the first OFDM symbol. For symbol n+1, if after performing IFFT, the values ​​of M specific time domain positions in OFDM symbol n+1 are equal to the first M time domain values ​​of OFDM symbol n, it is equivalent to performing CP extension on symbol n+1.

[0303] It should be noted that the equality here refers to the engineering significance. When the difference between two values ​​is less than the error range, they can be considered equal. The specific error range is implemented by the sender (for example, the error range is 3% or 5%).

[0304] This step takes M=368 as an example to describe the content of "the values ​​of M specific time domain positions in OFDM symbol n+1 are equal to the first M=368 time domain values ​​of OFDM symbol n".

[0305] Description method 1: For OFDM symbol n, in the sequence formed after IFFT transformation, the first M = 368 sequence values ​​are Y0;

[0306] For OFDM symbol n+1, after IFFT transformation and CP addition, the first M=368 sequence values ​​are Y1;

[0307] The above Y0 is equal to Y1.

[0308] Description Method 2:

[0309] For OFDM symbol n: Assuming the frequency domain data length N = 2048, after IDFT transformation, the data OFDM data sequence x is formed 0 ,x 1 ,…x N-2 ,x N-1 ; The first M (e.g. M = 368) time domain values ​​are: v 0 , v 1 , v 2 ,…v M-1 ;

[0310] For OFDM symbol n+1: Assume the frequency domain data length After IDFT transformation, the data OFDM data sequence x is formed 0 ,x 1 ,…xN-2 ,x N-1 ;

[0311] Among them, for m = 0 to The following values ​​need to meet the conditions:

[0312]

[0313] Among them, the above is the last OFDM symbol n+1 A data sequence, which is also the original CP data of the symbol.

[0314] for To M-1, the following values ​​need to meet the conditions:

[0315]

[0316] The above are the first 224 data sequences of OFDM symbol n+1.

[0317] in: Indicates the length before CP extension.

[0318] The relationship between the IFFT time domain output samples of OFDM symbol n+1 and OFDM symbol n is as follows: Fig.13 As shown, the M time domain values ​​of the latter symbol are equal to the first M time domain values ​​of the former symbol.

[0319] The following describes how to determine the positions of the M1 frequency domain reserved resources and the values ​​corresponding to the positions of the M1 frequency domain resources.

[0320] Assume that M1 takes the value M, and the input frequency domain data is X(n), n=0,1,…N-1;

[0321] Among them, there are M1 frequency domain data {X(k 0 ),X(k 1 ),…X(k M1-1 )} does not transmit any information, that is, any value can be set to meet the requirement that the above M data sequences are the same; here k 0 ,k 1 ,…k M1-1 , is a non-repeating integer greater than or equal to 0 and less than or equal to N-1. 0 ,k 1 ,…k M1-1 The number of combinations is: That is, select the combination of M1 elements from N elements.

[0322] The other frequency domains are used to transmit data (i.e., the data in other frequency domains are fixed values ​​and cannot be changed).0 ),X(k 1 ),…X(k M-1 )}.

[0323] According to the following IDFT formula:

[0324]

[0325] We can list M1-variable linear equations, and there are M M1-variable linear equations in total. That is, by solving M M1-variable linear equations, we can get a set of "numerical solutions".

[0326] Furthermore, due to k 0 ,k 1 ,…k M1-1 The number of combinations of is K, that is, at least K groups of “numerical solutions” can be obtained.

[0327] Find a set of "appropriate" values ​​from K sets of "numerical solutions", that is, determine the "appropriate" position and the "appropriate" value.

[0328] The solution that satisfies the "appropriate" value can be any of the following:

[0329] 1) The modulus of all M1 values ​​is less than a threshold;

[0330] 2) The average value of the modulus of M1 values ​​is less than a threshold.

[0331] It should be noted that when solving a linear equation of M1, the "numerical solution" may not be the numerical value of the solution to the equation in the mathematical sense. When the error between two numerical values ​​is within a certain range, it can be considered as the solution to the equation.

[0332] In addition to being greater than or equal to M, the value of M1 can also be less than M. Considering the randomness of the input data of OFDM symbol n+1, there may be other situations where the number of reserved resources is less than M (such as M1=0, M1=M / 2), and the above equation relationship is satisfied.

[0333] On the M1 frequency domain reserved resources, the data can be transmitted in a rate matching manner (i.e., bypassing these resources when mapping data) or in a puncturing manner (i.e., data can be mapped to the frequency domain reserved resources, and the receiving end considers that it is punctured);

[0334] Among the combinations of M1 frequency domain reserved resources, the combinations occupying important frequency domain positions are discarded, for example, the original RE positions are used to transmit PDCCH or DMRS.

[0335] Step 43a: Indicate information of one or more OFDM symbols n to the terminal, and send OFDM symbol data.

[0336] The OFDM symbols n (one or more) that need to be CP extended and the extension amount M are determined and configured by the network device through high-level signaling or indicated by dynamic scheduling signaling.

[0337] One or more CP extended symbols configured by the network device through high-level signaling: may be all downlink symbols (time slots) on the carrier, or part of the downlink symbols (time slots).

[0338] The network device indicates one or more CP extended symbols through scheduling signaling: it may be all symbols or part of the scheduled symbols.

[0339] Specifically, there are two methods for determining the M value:

[0340] (1) The network device only indicates the extended CP length, and the extension increment M is calculated by the terminal itself.

[0341] For example, the network device indicates that the extended CP length is 512. Then:

[0342] If the CP length before extension is 144, then M is equal to 512-144=368;

[0343] If the CP length before extension is 160, then M is equal to 512-160=352.

[0344] (2) The base station directly indicates the increment M;

[0345] For example, the base station indicates two M values, namely M = 368 and M = 35.

[0346] If the CP length before extension is 144, then M = 368;

[0347] If the CP length before extension is 160, then M=352.

[0348] This embodiment assumes that the network device determines the value of M using the above method (1).

[0349] The network device sends OFDM symbols after processes such as CP addition.

[0350] It should be noted that the above steps 41a and 42a are implemented by the network device itself. When the network device configures one or more CP extended symbols through high-level signaling, it can further indicate the sending of common messages (such as: physical broadcast channel (PBCH), remaining minimum system information (RMSI) information, paging information), the control channel for sending common messages, and whether to use extended CP OFDM symbol transmission.

[0351] Terminal side:

[0352] Step 41b: Determine the CP time domain extension increment M.

[0353] The terminal receives configuration or indication information of the network device, which is used by the UE to obtain the CP time domain extension increment M. The extension increment M is relative to the CP length before extension, and its unit can be microseconds (or milliseconds), sampling points, or IFFT sample time units.

[0354] The network device may directly indicate the value of the extended increment M, or may indicate the extended CP length. If the extended CP length is indicated, the UE may determine the increment M based on the current symbol CP length and the extended CP length.

[0355] For ease of description, it is assumed here that the unit of M is the same as the time unit of the FFT sample point. For example, assuming the number of IFFT sample points is 2048;

[0356] The CP length before expansion is 144, and the CP length after expansion is 512, so M is equal to 512-144=368;

[0357] The CP length before extension is 160, and the CP length after extension is 512, so M is equal to 512-160=352.

[0358] Step 42b: Receive CP-extended OFDM symbol n information.

[0359] The terminal receives indication information sent by the network device, where the information is used to indicate one or more OFDM symbols n (1 or more) for CP extension, and may be a high-level signaling configuration sent by the network device, or a dynamic scheduling signaling.

[0360] One or more CP extended symbols configured by the network device through high-level signaling: may be all downlink symbols (time slots) or part of downlink symbols (time slots) on the serving cell.

[0361] The network device indicates one or more CP extended symbols through scheduling signaling: it may be all symbols or part of the scheduled symbols.

[0362] For the OFDM symbol n with CP extension, the UE determines the timing information for receiving the symbol (i.e., the starting position of the receiving data window for performing DFT) according to the value of M. Specifically, assuming that the synchronization time determined by the UE according to the synchronization signal is t0, the time of receiving OFDM symbol n is delayed by M time units, i.e., t0+t(M).

[0363] As another optional embodiment, it is assumed that the network device indicates to the terminal the target OFDM symbol that needs to be CP extended, and indicates information of M1 frequency domain reserved resources of the first OFDM symbol.

[0364] This embodiment only describes how the network device indicates information about M1 frequency domain reserved resources, and other parts are the same as the above optional embodiments and are not described in detail here.

[0365] The information of the relevant M1 frequency domain reserved resources is configured by the network device through high-level signaling or indicated by dynamic scheduling signaling.

[0366] One or more CP extended symbols configured by the network device through high-level signaling: may be all downlink symbols (time slots) on the carrier, or part of the downlink symbols (time slots).

[0367] The network device indicates one or more CP extended symbols through scheduling signaling: it may be all symbols or part of the scheduled symbols.

[0368] The following example illustrates the use of scheduling signaling to indicate information of M1 frequency domain reserved resources of one or more symbols.

[0369] Method 1: K bitmap indications are configured through high-level signaling to indicate which resources among N frequency domain resources are frequency domain reserved resources.

[0370] Assuming N=8, the network device is configured with 4 bitmap indications, indicating 4 reserved resources in the mid-frequency domain, as shown in the following Table 1:

[0371] Table 2: High-layer signaling indicates frequency domain reserved resources

[0372]

[0373] Method 2: The network device indicates the configuration index in the dynamic scheduling signaling.

[0374] It should be noted that when the network device instructs OFDM symbol n to perform CP extension, M1 frequency domain reserved resources are applied to OFDM symbol n+1, that is, the next symbol to which the CP extension symbol is applied.

[0375] When the scheduling signaling schedules multiple symbols such as num=7, and all 7 symbols need to extend the CP, the M1 frequency domain reserved resources of all 7 corresponding symbols can use the same configuration index or different configuration indexes, which is not limited here.

[0376] For the last extended CP symbol of the scheduled data, the information of its M1 frequency domain reserved resources can be exempted from indication. When the scheduling signaling schedules multiple symbols such as num=4 (such as: syb1, syb2, syb3, syb4), and all 4 symbols need to extend the CP, the M1 frequency domain reserved resources corresponding to the last symbol syb4 are applied to syb5, but syb5 is not within the scope of the scheduling signaling. Therefore, for syb5, the method of exempting from indication can be used. In the case of exempting from indication, the method for the terminal to determine the frequency domain reserved resources refers to the above embodiment, which will not be repeated here.

[0377] As an optional embodiment, for the method of determining M1 "appropriate" frequency domain reserved resource positions and the "appropriate" value of the frequency domain reserved resource, in addition to traversing all positions, other methods can also be used for optimization. The specific optimization method is as follows:

[0378] Step 51: The M1 frequency domain reserved resources are preferentially placed on the protection bandwidth and out-of-band RE resources.

[0379] In this embodiment, the M1 frequency domain reserved resources are preferentially placed on the protection bandwidth and out-of-band RE resources. The power corresponding to the set data value does not exceed the threshold range specified by the standard protocol.

[0380] For example, assume that the parameters are: FFT transform parameter N = 2048, communication bandwidth is 10MHz (equivalent to 55 RBs, i.e. 660 REs); guard band is 2RBs, which is equivalent to 24 REs. In N = 2048 REs, the number of out-of-band REs is = 2048-660 = 1388; Fig.14 As shown:

[0381] In a channel bandwidth of 10MHz, assuming that the maximum power transmitted by the network device is 40 watts, the maximum transmission power is 4 watts per 1MHz bandwidth, which is converted into dBm as follows: 10*lg(4*1000)=36dBm. Assuming that the input of IFFT is 16 bits (i.e., the value range is -32768 to 32767), the setting range of the out-of-band frequency and the guard band frequency domain is as shown in Table 3 below:

[0382] Table 3: Setting range of out-of-band frequency and guard band frequency domain

[0383]

[0384]

[0385] The calculation method for the above value setting range is: When the maximum transmit power is -13dBm:

[0386] The ratio of the power value range of communication and out-of-band is: power(10,(36+13) / 10)=79810; power() is an exponential function;

[0387] The ratio of the communication and out-of-band ranges is: sqrt(79810) = 282;

[0388] The out-of-band value range is: 32767 / 282=115.

[0389] Step 52: Determine the location of the frequency domain reserved resource on the communication frequency

[0390] Through step 52, a part or all of the M1 frequency domain reserved resources are preferentially determined. If the above-mentioned extended CP function can be achieved through step 52, there is no need to set the frequency domain reserved resources on the communication frequency. That is, there is no need to indicate the information of the frequency domain reserved resources to the UE.

[0391] Furthermore, when setting the frequency domain reserved resources on the communication frequency, if the frequency domain reserved resources are not included in the frequency domain resources for data scheduling, there is no need to indicate the information of the frequency domain reserved resources to the UE.

[0392] The protection bandwidth in the above embodiment: in the authorized spectrum, in order to avoid frequency domain interference of adjacent channels, usually, the transmitting end needs to reserve some frequency domain RE resources. The power of these frequency domain reserved resources needs to be strictly limited, that is, the power cannot exceed a certain threshold. Usually, the network device does not send any data information on these frequency domain reserved resources; for example: assuming SCS = 15KHz, the base station is allocated a bandwidth of 10MHz, with a total of 55 RBs (equivalent to 660 RE resources, one RB contains 12 REs), the network device and the terminal only communicate in 53 RBs (referred to as communication bandwidth), that is, 2 RBs are reserved and no information is sent.

[0393] For out-of-band leakage limit: When the transmitter sends a signal, due to the limitation of the implementation device, the relevant signal will not only be transmitted in the communication channel, but also leak out of the communication bandwidth. The leaked signal power cannot exceed a certain threshold. The out-of-band leakage threshold values ​​are shown in Table 4 below.

[0394] In the above embodiment of the present application, for the nth OFDM symbol to be transmitted, the "appropriate" position and "appropriate" value of M1 RE resources are selected on the N REs input to the IFFT, so as to achieve the effect of extending the CP length of M samples for the n-1th OFDM symbol. The network device indicates the symbol n that needs to be CP extended and the extension increment of the CP, and can indicate the information of M1 frequency domain reserved resources.

[0395] Table 4: Out-of-band leakage threshold values

[0396]

[0397] It should be noted that M1 is only related to the FFT size and CP extension, and has nothing to do with the actual number of occupied PRBs. In theory, the M1 RE resource location can be any location. If optimized, the value of M1 can be less than M, or greater than or equal to M. The implementation effect is as follows Fig.15 Assume that for symbol n-1, the CP needs to be extended by 1 FFT sample point. Then, by setting the data of "appropriate" value in the RE resource at the specific k0 position of symbol n, the effect of extending the CP of symbol n-1 from 2 FFT sample points to 3 FFT sample points can be achieved.

[0398] Assuming that k0 is 0, in order to make the symbol n-1 achieve the effect of CP expansion to 3 FFT sample points, that is, the CP data is "781", it is necessary to ensure that the first number of the CP data of symbol n is "1", which corresponds to the value of the second to last data of the IFFT output of symbol n. That is, X(k0-0) needs to be set to a "suitable" value so that the (N-2) value of the time domain value of symbol n is "1".

[0399] For k0, the following method can be used to confirm the value of X(k0): Assuming that the length of the FFT is N, the penultimate data of symbol n has a "suitable" value of "1", which can be expressed as: x(N-2) = "1"

[0400] From the IDFT formula, we can know that:

[0401]

[0402] Then we have:

[0403] Right now:

[0404] From the above numerical method for calculating X(k0), it can be known that different k0 values ​​correspond to different X(k0) values. Considering that the reserved resources are not used to transmit any information, the smaller the X(k0) value, the smaller the power occupied by the RE resources. Therefore, the best practice is to traverse all k0 values ​​so that the corresponding X(k0) value is the smallest, or X(k0) is less than a certain threshold. Therefore, the "appropriate" reserved resource RE position k0 can be understood as the minimum X(k0) value, or less than a certain threshold. This method does not cause modifications to the physical layer structure, can reduce the complexity of protocol formulation, and does not increase the implementation cost of the equipment. It is compatible with older versions of UE.

[0405] In the above example, the first OFDM symbol is an adjacent symbol after the target OFDM symbol. In an embodiment of the present application, the first OFDM symbol may also be an adjacent symbol before the target OFDM symbol that requires CP extension.

[0406] For example, the target OFDM symbol is symbol n+1, and the first OFDM symbol is n. For symbol n, the network device determines the "appropriate" positions and "appropriate" values ​​of M1 reserved RE resources, so that after performing IFFT, the last M time domain values ​​in OFDM symbol n are equal to the M specific time domain values ​​in symbol n+1. Here, it is assumed that symbol n+1 is an OFDM symbol that needs CP extension.

[0407] For symbol n+1, if after performing IFFT, the values ​​of M specific time domain positions in OFDM symbol n+1 are equal to the last M time domain values ​​of OFDM symbol n, it is equivalent to performing CP extension on symbol n+1.

[0408] For example: for the symbol n+1:

[0409] The expected CP length after extension NECP=512, the CP length before extension NCP=144, and the CP extension increment M=368.

[0410] Assuming that the frequency domain data length N = 2048, after IDFT transformation, the data OFDM data sequence x is formed 0 ,x 1 ,…x N-2 ,x N-1 , where the first value in the last M numerical sequences is: x N-NECP =x 1536 .

[0411] Then: M in symbol n+1 symbol = 368 specific time domains x 1536 , x 1537 , …x 1903 , corresponding to the value v 0 , v 1 ,…v M-1 .

[0412] For symbol n:

[0413] Assume that the frequency domain data length is , after IDFT transformation, the data OFDM data sequence x is formed 0 ,x 1 ,…x N-2 ,x N-1 ;

[0414] The final M=368 data is: xN-1-M+1 , x N-1-M+2 ,…x N-1 ; respectively corresponding to the value v 0 , v 1 ,…v M-1 ;

[0415] in: Indicates the number of IFFT samples before CP expansion.

[0416] The relationship between the IFFT time domain output samples of OFDM symbol n+1 and OFDM symbol n is as follows: Fig.16 shown.

[0417] For symbol n, the method for the network device to determine the "appropriate" positions of M1 reserved RE resources and the "appropriate" values ​​is as follows:

[0418] Assume that the input frequency domain data is X(n), n=0,1,…N-1;

[0419] Among them, there is M1 frequency domain data {X(k 0 ),X(k 1 ),…X(k M1-1 )} does not transmit any information, that is, any value can be set. By setting a suitable frequency domain value of M1, symbol n can satisfy the requirement that the above M data sequences are the same after IFFT transformation;

[0420] Here k 0 ,k 1 ,…k M1-1 , is an integer greater than or equal to 0 and less than or equal to N-1 and does not repeat. 0 ,k 1 ,…k M1-1 The number of combinations is: ; That is, select the combination types of M1 elements from N elements. The other frequency domains except the M1 frequency domain positions are used to transmit data (that is, the other frequency domain data are fixed values ​​and cannot be changed).

[0421] The following describes how to determine the M1 data {X(k 0 ),X(k 1 ),…X(k M-1 )}.

[0422] Assume that the frequency domain data {X(k 0 ),X(k 1 ),…X(k M-1 )} is the unknown number to be determined. The time domain sequence x 0 ,x 1 ,…x N-2 ,x N-1There are M known data. According to the following IDFT formula:

[0423]

[0424] When M1 is greater than or equal to M, M linear equations with M1 variables can be listed. That is, by solving M linear equations with M1 variables, at least one set of "numerical solutions" can be obtained.

[0425] Furthermore, due to k 0 ,k 1 ,…k M1-1 The number of combinations is K That is, at least K groups of "numerical solutions" can be obtained.

[0426] Find a set of "appropriate" values ​​from the K sets of "numerical solutions", that is, determine the "appropriate" locations and "appropriate" values ​​of the M1 reserved resources.

[0427] A solution that satisfies a "suitable" value can be defined as one that satisfies at least one of the following conditions:

[0428] The modulus of all M1 values ​​is less than a threshold;

[0429] The average value of the moduli of the M1 values ​​is less than a threshold.

[0430] It should be noted that when solving a linear equation of M1, the "numerical solution" may not be the numerical value of the solution to the equation in the mathematical sense. When the error between two numerical values ​​is within a certain range, it can be considered as the solution to the equation.

[0431] In addition to being greater than or equal to M, the value of M1 can also be less than M. Considering the randomness of the input data of OFDM symbol n+1, there may be other situations where the number of reserved resources in the frequency domain is less than M (such as M1=0, M1=M / 2), and the above equation relationship is satisfied.

[0432] On the M1 frequency domain reserved resources, the data can be transmitted in a rate matching manner (i.e., bypassing these resources when mapping data) or in a puncturing manner (i.e., data can be mapped to the frequency domain reserved resources, and the receiving end considers that it is punctured);

[0433] Among the combinations of M1 frequency domain reserved resources, the combinations occupying important frequency domain positions are discarded, for example, the original RE positions are used to transmit PDCCH or DMRS.

[0434] It should be noted that, in the case where the first OFDM symbol is an adjacent symbol before the target OFDM symbol that needs CP extension, the network device does not need to indicate the information of the CP extension increment M to the terminal, and the terminal side does not need to calculate the value; but the sending end needs to perform symbol reverse processing, such as processing symbol n+1 first, and then processing symbol n. Considering that public signaling needs to be compatible with old versions of UE, this method can be used for sending public signaling, thereby improving the reception performance of public signaling, such as using this method to send SSB, SIB1 information, etc.

[0435] In the case where the first OFDM symbol is an adjacent symbol before the target OFDM symbol that needs to be CP extended, the network device only needs to send information of M1 reserved resources of the first OFDM symbol to the terminal and send OFDM symbol data.

[0436] The following describes an example of an implementation method for indicating information of M1 frequency domain reserved resources of one or more symbols using scheduling signaling.

[0437] Method 1: K bitmap indications are configured through high-level signaling to indicate which resources among N frequency domain resources are reserved frequency domain resources.

[0438] Assuming N=8, the base station configures 4 bitmap indications to indicate 4 types of frequency domain reserved resources, as shown in the following Table 5:

[0439] Table 5: High-layer signaling indicates frequency domain reserved resources

[0440]

[0441] Method 2: The network device indicates the configuration index in the dynamic scheduling signaling.

[0442] It should be noted that when CP extension is performed on OFDM symbol n+1, M1 frequency domain reserved resources are applied to OFDM symbol n, that is, applied to the symbol before the CP extension symbol.

[0443] When the scheduling signaling schedules multiple symbols such as num=7, and all 7 symbols need to extend the CP, the M1 frequency domain reserved resources of all 7 corresponding symbols can use the same configuration index or different configuration indexes, which is not limited here.

[0444] For the symbol of the first extended CP of the scheduled data, the information of the M1 frequency domain reserved resources can be exempted from indication, which will not be described in detail here. When the scheduling signaling schedules multiple symbols such as num=4 (such as: syb1, syb2, syb3, syb4), and all 4 symbols need to extend the CP, the M1 reserved resources corresponding to the first symbol syb1 are applied to syb0, so the method of exempting from indication can be used for syb0. In the case of exempting from indication, the method for the terminal to determine the frequency domain reserved resources refers to the above embodiment, which will not be described in detail here.

[0445] The terminal receives information about M1 frequency domain reserved resources sent by the network device. The information is used to determine the position information of the M1 reserved REs, which may be high-level signaling configuration or dynamic scheduling signaling sent by the network device.

[0446] For example, the network device configures the information of M1 frequency domain reserved resources through high-level signaling: the information can be applied to all downlink symbols (time slots) on the carrier, or part of the downlink symbols (time slots). Alternatively, the network device indicates one or more "M1 frequency domain reserved resource information" through scheduling signaling: it can be all symbols of the scheduled symbols, or part of the symbols.

[0447] The above "information of M1 frequency domain reserved resources" is applied to OFDM symbol n, that is, the adjacent symbol of OFDM symbol n+1 for CP or OFDM symbol n+1. On the terminal side, these resources are considered unavailable resources, that is, the network device is considered not to send data on these resources.

[0448] It should be noted that each CP-extended OFDM symbol n+1 corresponds to an OFDM symbol n to which "information of M1 frequency domain reserved resources" is applied. When there are multiple CP-extended OFDM symbols n+1, they correspond to multiple OFDM symbols n to which "information of M1 frequency domain reserved resources" is applied.

[0449] This embodiment can achieve the effect of extending the CP without changing the frame structure (i.e., there is no need to modify 1 time slot containing 14 symbols to 1 time slot containing 12 symbols). At the same time, the network equipment can flexibly set the CP increment M according to actual business needs to meet the requirements of the distance between different cells in the SFN area. At the same time, the old version of UE can also obtain the benefits brought by the extended CP.

[0450] The following takes downlink data transmission as an example to illustrate the implementation effect of this embodiment when the first OFDM symbol is an adjacent symbol before the target OFDM symbol.

[0451] For example, suppose an OFDM symbol includes: 2 units of CP; 8 units of data (i.e., the number of IFFT points). When the multipath delay difference τ is less than or equal to 2 units, there is no mutual interference between the multipaths; when the multipath delay difference τ is equal to 3 units, there is interference between the multipaths, such as Figure 5 As shown. Correspondingly, if the length of CP is 3 time units, there is no inter-symbol interference, as shown in Figure 6 shown.

[0452] The following describes the CP extension of symbol 1 and symbol 2, with the extension amount M = 1, such as Fig.17 Assume that the IDFT output of symbol 3 is {I, J, K, L, M, n, o, p}. That is, the first value is: x N-NECP =x 5 =“n”.

[0453] At a specific frequency domain position of symbol 2, set a "suitable value" so that: in the IDFT output sequence of symbol 2, the last M = 1 data: x N-1-M+1 =x 7 , should be equal to "n".

[0454] Assume that the IDFT output sequence of symbol 2 is finally: {a,b,c,d,e,f,g,n}. That is, the first value of symbol 2 is: x N-NECP =x 5 =“f”.

[0455] At a specific frequency domain position of symbol 1, set a "suitable value" so that: in the IDFT output sequence of symbol 1, the last M = 1 data: x N-1-M+1 =x 7 , should be equal to "f".

[0456] Assume that the IDFT output sequence of symbol 1 is finally: {1,2,3,4,5,6,7,f}.

[0457] The transmitting end (here, the network device) adds CP according to the frame structure parameter of CP=2 to form OFDM transmission data.

[0458] At the receiving end (here, the terminal), the starting position of the DFT input window is still set according to CP=2, and the DFT operation (time domain to frequency domain) is performed. Fig.18 It can be seen that when the multipath difference is 3 units:

[0459] For symbol n+2: the multipath data in the DFT window includes: {I, J, Q, L, M, n, o, p}. That is, the multipath information is a periodic signal, and there is no inter-symbol interference in the multipath.

[0460] For symbol n+1: the multipath data in the DFT window includes: {a,b,c,d,e,f,g,n}. That is, the multipath information is a periodic signal, and there is no inter-symbol interference in the multipath.

[0461] It should be noted that, at the UE end, the input window of the DFT can still maintain the synchronization time obtained according to the synchronization signal (the starting window position of the original DFT of the symbol), which has nothing to do with the value of M.

[0462] In another optional embodiment, it is assumed that the OFDM symbol includes: 2 units of CP; 8 units of data (ie, the number of IFFT points). When the multipath delay difference τ is less than or equal to 2 units, there is no mutual interference between the multipaths; when the multipath delay difference τ is equal to 5 units, there is interference between the multipaths. Fig. 9 As shown. Correspondingly, if the length of CP is 5 time units, there is no inter-symbol interference, as shown in Fig.10 shown.

[0463] The following describes the CP extension of symbol 1 and symbol 2, with the extension amount M=3.

[0464] like Fig.19 As shown, it is assumed that the IDFT output of symbol 3 is {I, J, K, L, M, n, o, p}. That is, the first value is: x N-NECP =x 3 = "L", starting from the first value, the M value sequences are: x 3 =L,x 4 =M,x 3 =N;

[0465] At a specific frequency domain position of symbol 2, set a "suitable value", so that: in the IDFT output sequence of symbol 2, the last M = 3 data: x N-1-M+1 =x 5 ,x 6 ,x 7 Should be equal to "L", "M", "N" respectively.

[0466] Assume that the IDFT output sequence of symbol 2 is finally: {a,b,c,d,e,L,M,N}. That is, the first value of symbol 2 is: x N-NECP =x 3 = "d", starting from the first value, the M value sequences are: x 3 =d,x 4 =e,x 3 =L;

[0467] At a specific frequency domain position of symbol 1, set a "suitable value", so that: in the IDFT output sequence of symbol 1, the last M = 3 data: x N-1-M+1 =x7 ,x 6 ,x 7, Should be equal to "d", "e", "L" respectively.

[0468] Assume that the IDFT output sequence of symbol 1 is finally: {1,2,3,4,5,d,e,L}.

[0469] The transmitting end adds CP according to the frame structure parameter of CP=2 to form OFDM transmission data.

[0470] At the receiving end, the starting position of the DFT input window is set according to CP=5, and the DFT operation (time domain to frequency domain) is performed. Fig. 20 It can be known that when the multipath difference is 5 units;

[0471] For symbol n+2: the multipath data in the DFT window includes: {I, J, Q, L, M, n, o, p}. That is, the multipath information is a periodic signal, and there is no inter-symbol interference in the multipath.

[0472] For symbol n+1: the multipath data in the DFT window includes: {a,b,c,d,e,f,g,n}. That is, the multipath information is a periodic signal, and there is no inter-symbol interference in the multipath.

[0473] It should be noted that the DFT input window at the UE can still use the starting window position of the original DFT symbol. That is, the synchronization time obtained according to the synchronization signal can still be applied to the starting position of the DFT window after the extension of the CP, without delaying M time units, that is, the UE uses the starting window position of the original DFT to connect to symbol n+1, which can achieve the purpose of extending the CP (such as Fig. 20 As shown, the extended CP is considered to be "f, g, n", the actual symbol length does not change and the CP structure is not changed).

[0474] This embodiment does not cause modification of the physical layer structure, can reduce the complexity of protocol formulation, and does not increase the cost of device implementation. This method is compatible with old version UEs, and old version UEs can obtain the gain of extending CP.

[0475] In this embodiment, for the nth OFDM symbol to be transmitted, the "appropriate" position and "appropriate" value of M1 RE resources are selected on the N REs input to the IFFT, so as to achieve the effect of extending the CP length of M samples for the n+1th OFDM symbol. The implementation effect is as follows: Fig.21 As shown. Fig.21In the figure, assuming that for symbol n+1, the CP needs to be extended by 1 FFT sample point, then for symbol n, the RE resource at the specific k0 position is set with a "suitable" value of data, which can achieve the effect of extending the CP of symbol n+1 from 2 FFT sample points to 3 FFT sample points.

[0476] Assuming k0 is 0, in order to achieve the effect of CP expansion of symbol n+1 to 3 FFT sample points, that is, the CP data is "fh g", it is necessary to ensure that the last number of the time domain data of symbol n is "f", which corresponds to the value of the third last data of the IFFT output of symbol n. That is, X(k0-0) needs to be set to a "suitable" value so that the (N-1) value of the time domain value of symbol n is "f";

[0477] Assuming k0 is 0, the value of X(k0) can be confirmed using the following method:

[0478] Assuming the length of FFT is N, the "appropriate" value of the last data is "1", which can be expressed as: x(N-1) = "f";

[0479] From the IDFT formula, we can know that:

[0480]

[0481] Then we have:

[0482] Right now:

[0483] From the above numerical method for calculating X(k0), it can be known that different k0 values ​​correspond to different X(k0) values. Considering that the frequency domain reserved resources are not used to transmit any information, the smaller the X(k0) value is, the smaller the power occupied by its RE resources is. Therefore, the best practice is to traverse all k0 values ​​so that the corresponding X(k0) value is the smallest, or X(k0) is less than a certain threshold.

[0484] In an embodiment of the present application, the terminal receives the relevant information of the extended CP sent by the network device, so that the target OFDM symbol and the extended increment of the CP that need to be extended can be determined. According to the extended increment of the CP, the terminal can adjust the starting position of the received target OFDM symbol. By adjusting the starting position of the received target OFDM symbol, the effect of extending the CP can be achieved without changing the physical layer frame structure. The terminal can determine the unavailable position in the data transmission based on the information of the frequency domain reserved resources of the adjacent symbols of the target OFDM symbol sent by the network device, thereby improving the data reception efficiency; the terminal can also obtain the uplink OFDM symbol to be sent based on the information of the frequency domain reserved resources, so as to achieve the effect of extending the CP without changing the physical layer frame structure (the method for obtaining the uplink OFDM symbol to be sent is the same as the method for the network device to generate the OFDM symbol to be sent, which will not be repeated here). . This scheme achieves the effect of extending the CP without changing the physical layer frame structure, the device implementation cost is low, and it is compatible with the terminal services of the old version, and can save air interface resources.

[0485] like Fig. 22 As shown, the embodiment of the present application also provides a method for extending a cyclic prefix, which is applied to a network device, including:

[0486] Step 221: The network device sends relevant information of the extended cyclic prefix CP and / or information of the frequency domain reserved resources of the first OFDM symbol to the terminal;

[0487] The relevant information of the extended CP is used to indicate the target OFDM symbol using the extended CP and the extended increment of the CP; and the first OFDM symbol is adjacent to the target OFDM symbol.

[0488] In this embodiment, the network device can determine the extension increment M of the CP based on the service transmission quality requirements and the deployed station spacing information. The extension increment M of the CP is relative to the CP length before extension, and its unit can be microseconds (or milliseconds), sampling points, or IFFT sample point time units.

[0489] The network device may send the relevant information of the extended CP to the terminal, indicating the target OFDM symbol and the extended increment of the CP that the terminal needs to perform CP extension. The target OFDM symbol may be one or more. The terminal adjusts the starting position of the received target OFDM symbol according to the relevant information of the extended CP, thereby achieving the purpose of extending the CP of the target OFDM symbol.

[0490] The network device can also determine the M1 frequency domain reserved resources of the first OFDM symbol and the value of the frequency domain reserved resources. Taking the first OFDM symbol as an example, which is the symbol after the target OFDM symbol that needs CP extension, by setting the value of the frequency domain reserved resources, after executing IFFT, the time domain values ​​of M specific positions in OFDM symbol n+1 can be equal to the first M time domain values ​​of OFDM symbol n.

[0491] Assume that symbol n is an OFDM symbol that needs CP extension. For symbol n+1, if after performing IFFT, the values ​​of M specific time domain positions in OFDM symbol n+1 are equal to the first M time domain values ​​of OFDM symbol n, it is equivalent to performing CP extension on symbol n+1.

[0492] The network device may also send to the terminal information about the reserved resources of the adjacent symbols (i.e., the first OFDM symbol) of the target OFDM symbol that needs to extend the CP. The reserved resources are the reserved resources before the first OFDM symbol is transformed, and the reserved resources refer to frequency domain resources. The information about the reserved resources may include: the position of the reserved resources and the value of the position. Before performing the transformation, the network device can implement CP extension for the target OFDM symbol by setting the value of the reserved resources.

[0493] In an embodiment of the present application, the network device indicates to the terminal the relevant information of the extended CP, so that the terminal can determine the target OFDM symbol for which the CP extension is required and the extended increment of the CP. The network device can indicate to the terminal the information of the frequency domain reserved resources of the adjacent symbols of the target OFDM symbol, so that the terminal can determine the unavailable position in the data transmission, thereby improving the data reception efficiency; the terminal can also obtain the uplink OFDM symbol to be sent based on the information of the frequency domain reserved resources, so as to achieve the effect of extending the CP without changing the physical layer frame structure. This solution achieves the effect of extending the CP without changing the physical layer frame structure, the device implementation cost is low, and it is compatible with the terminal services of the old version, which can save air interface resources.

[0494] It should be noted that: the downlink data symbol sending process described in this technical solution, that is, the terminal is the receiving end of the data symbol; the network device is the sending end of the data symbol. The relevant technology can also be applied to the transmission process of uplink data sending. At this time, the terminal is the sending end, the network device is the receiving end, and the information configuration and indication are performed by the network device. That is: for the transmission of uplink data, it is still the network device that sends the relevant information of the extended CP to the terminal, and / or the information of the frequency domain reserved resources of the first OFDM symbol. The terminal performs the data sending process based on the received information, and the data sending process may include: data mapping, transformation, adding CP, sending symbols and other processes. The network device receives the uplink data sent by the terminal.

[0495] Optionally, the relevant information of the extended CP includes at least one of the following:

[0496] 1) Information indicating the target OFDM symbol using the extended CP; this information may indicate which one or more symbols need to be CP extended.

[0497] 2) Extension increment of CP: The extension increment of CP is an increment relative to the CP length before extension, and its unit can be microseconds (or milliseconds), or sampling points, or the time unit of IFFT sample points.

[0498] Optionally, the method further includes: determining an extended increment of CP, wherein the extended increment of CP is an increment relative to the number of conventional CPs; and determining relevant information of the extended CP according to the extended increment of CP. The network device may determine the extended increment of CP based on the service transmission quality requirements and the spacing information of the deployed network devices, thereby generating relevant information of the extended CP.

[0499] 3) Length of the extended CP: The network device may also directly indicate the length of the extended CP, and the CP extension amount may be obtained by calculation.

[0500] In this embodiment, the network device may directly indicate the value of the extension increment, or may indicate the extended CP length. If the extended CP length is indicated, the terminal may determine the extension increment according to the CP length of the current symbol and the extended CP length.

[0501] As an optional embodiment, the sending the relevant information of the extended cyclic prefix CP and / or the information of the frequency domain reserved resources of the first OFDM symbol to the terminal includes:

[0502] A high-layer signaling and / or a scheduling signaling is sent to the terminal, wherein the high-layer signaling and / or the scheduling signaling carries relevant information of the extended CP and / or information of frequency domain reserved resources of the first OFDM symbol.

[0503] In this embodiment, the network device sends the relevant information of the extended CP and / or the frequency domain reserved resource information of the first OFDM symbol to the terminal through high-level signaling and / or scheduling signaling. The scheduling information may be dynamic scheduling signaling. For example, the CP extension amount may be indicated by high-level information or by dynamic scheduling signaling, and the indicated value may be an extension increment M or the length of the extended CP.

[0504] For example, the network device configures one or more CP extended symbols through high-level signaling, and the symbols that need to be CP extended may be: all downlink symbols (time slots) on the serving cell, or part of the downlink symbols (time slots). Alternatively, the network device indicates one or more CP extended symbols through scheduling signaling, and the symbols that need to be CP extended may be: all symbols or part of the scheduled symbols.

[0505] As an optional embodiment, the method further includes:

[0506] Mapping the data to be sent to the frequency domain of the OFDM symbol to be sent;

[0507] For the first OFDM symbol, determining a position of the frequency domain reserved resource and a value of the frequency domain reserved resource;

[0508] Performing transformation to generate OFDM symbols to be transmitted;

[0509] Adding CPs to the OFDM symbol according to a conventional number of CPs;

[0510] The OFDM symbol is sent to a terminal.

[0511] In this embodiment, the network device maps the data to be sent to the corresponding frequency domain position, and determines the position and value of the OFDM reserved resources of the first OFDM symbol. IFFT transformation is performed to generate symbols to be sent in the time domain. The network device sends OFDM symbols to the terminal after processes such as CP addition. It should be noted that this step is for the downlink data transmission process, and the network device, as the data transmitter, needs to perform the above-mentioned transformation, add CP to send symbols and other steps. For uplink data transmission, the network device needs to adjust the starting position of the received target OFDM symbol based on the extended increment of CP, and adjust the starting position of the received target OFDM symbol to: the receiving starting position before CP expansion is delayed by M time domain positions;

[0512] Optionally, the frequency domain reserved resources of the first OFDM symbol are not used for downlink transmission or uplink transmission.

[0513] In this embodiment, the downlink transmission includes but is not limited to: PDSCH, PDCCH, CSI-RS, DMRS transmission. The network device can send relevant information about the OFDM reserved resources before the first OFDM symbol is transformed to the terminal, and the terminal receives the information to determine the numerical value of the position of M1 OFDM reserved resources. The information can be a high-level signaling configuration or dynamic scheduling signaling sent by the network device. It should be noted that for uplink transmission, the reserved resources before the first OFDM symbol is transformed are not used for uplink transmission.

[0514] As an optional embodiment, the first OFDM symbol is an adjacent symbol after the time domain position of the target OFDM symbol, and the values ​​of the M first time domain positions of the first OFDM symbol are the same as the values ​​of the first M time domain positions of the target OFDM symbol;

[0515] or,

[0516] The first OFDM symbol is an adjacent symbol before the time domain position of the target OFDM symbol, and the values ​​of the last M time domain positions of the first OFDM symbol are the same as the values ​​of the M second time domain positions of the target OFDM symbol;

[0517] Where M is the expansion increment of CP.

[0518] In this embodiment, the first OFDM symbol may be an adjacent symbol before the target OFDM symbol that needs to be CP extended, or may be an adjacent symbol after the target OFDM symbol. If the first OFDM symbol is an adjacent symbol before the target OFDM symbol, for example, the target OFDM symbol is symbol n, and the first OFDM symbol is symbol n+1, the network device sets the positions and values ​​of the M1 OFDM reserved resources of symbol n+1, so that after performing IFFT, the time domain values ​​of the M specific positions (i.e., the first time domain positions) in the OFDM symbol n+1 are equal to the first M time domain values ​​of the OFDM symbol n.

[0519] Optionally, the M first time domain positions include one of the following:

[0520] (1) The first M time domain positions of the first OFDM symbol after adding CP according to the conventional CP number.

[0521] For example, for OFDM symbol n, the first M sequence values ​​in the sequence formed after IFFT transformation are Y0;

[0522] For OFDM symbol n+1, the first M sequence values ​​in the sequence formed after IFFT transformation and adding CP are Y1;

[0523] The above Y0 is equal to Y1.

[0524] (2) When M is less than or equal to A, the M first time domain positions include: the time domain position of the first data and the subsequent M-1 time domain positions, the first data is: data whose sequence number is the difference between the total length of the data sequence and A; wherein A is the number of samples of the conventional CP (i.e., the number or length of CPs before extension);

[0525] (3) When M is greater than A, the 1st to Ath time domain positions in M ​​are: the time domain position of the first data and the subsequent A-1 time domain positions, where the first data is: data whose serial number is the difference between the total length of the data sequence and A; the A+1th to Mth time domain positions in M ​​are: the first MA time domain positions; where A is the number of samples of a conventional CP (i.e., the number or length of CPs before extension).

[0526] The above (2) and (3) are described in the second way: describing based on the relationship between M and the number of CP sample points A before expansion.

[0527] For example, for OFDM symbol n: Assuming the frequency domain data length is N, after IDFT transformation, the data OFDM data sequence x is formed. 0 , x 1 ,…x N-2 , x N-1 The first M time domain values ​​are: 0 , v 1 , v 2 ,…v M-1 .

[0528] For OFDM symbol n+1: Assume the frequency domain data length , after IDFT transformation, the data OFDM data sequence x is formed 0 ,x 1 ,…x N-2 ,x N-1 .

[0529] when The following values ​​need to satisfy the conditions:

[0530]

[0531] when hour:

[0532] For m = 0 to m is any value between 0 and M, and the following values ​​need to satisfy the conditions:

[0533]

[0534] for To M-1, the following values ​​need to meet the conditions:

[0535]

[0536] in: Indicates the number of IFFT samples before CP expansion.

[0537] The relationship between the IFFT time domain output samples of OFDM symbol n+1 and OFDM symbol n is as follows: Figure 4 As shown, the M time domain values ​​of symbol n+1 after transformation are equal to the first M time domain values ​​of symbol n.

[0538] Optionally, if the first OFDM symbol is the adjacent symbol after the target OFDM symbol, for example, the target OFDM symbol is symbol n+1, and the first OFDM symbol is symbol n, the network device sets the positions and values ​​of the M1 frequency domain reserved resources of symbol n so that after executing IFFT, the values ​​of the last M time domain positions in OFDM symbol n are equal to the values ​​of the M specific time domain positions (i.e., the second time domain positions) of OFDM symbol n+1.

[0539] Optionally, the M second time domain positions include: a difference between a total length of the data sequence and a total length of the extended CP and the time domain positions of subsequent M-1 data.

[0540] For example: for the symbol n+1:

[0541] The expected CP length after extension NECP=512, the CP length before extension NCP=144, and the CP extension increment M=368.

[0542] Assuming that the frequency domain data length N = 2048, after IDFT transformation, the data OFDM data sequence x is formed 0 ,x 1 ,…x N-2 ,x N-1 , where the first value in the last M numerical sequences is: x N-NECP =x 1536 .

[0543] Then: M in symbol n+1 symbol = 368 specific time domains x 1536 , x 1537 , …x 1903 , corresponding to the value v 0 , v 1 ,…v M-1 .

[0544] For symbol n:

[0545] Assume that the frequency domain data length is After IDFT transformation, the data OFDM data sequence x is formed 0 ,x 1 ,…x N-2 ,x N-1 ;

[0546] The final M=368 data is: x N-1-M+1 , xN-1-M+2 ,…x N-1 ; respectively corresponding to the value v 0 , v 1 ,…v M-1 ;

[0547] in: Indicates the number of IFFT samples before CP expansion.

[0548] The relationship between the IFFT time domain output samples of OFDM symbol n+1 and OFDM symbol n is as follows: Fig.16 shown.

[0549] This embodiment can achieve the effect of extending the CP without changing the frame structure (that is, there is no need to modify one time slot from containing 14 symbols to containing 12 symbols).

[0550] As an optional embodiment, the method further includes:

[0551] Select M1 frequency domain reserved resource positions from the N frequency domain positions, where M1 is greater than or equal to 0;

[0552] According to the M known data and the transformation formula, one or more sets of numerical solutions are determined, each set of numerical solutions corresponds to a resource location combination;

[0553] If the numerical solution is a group, determining the group of numerical solutions as the numerical value of the frequency domain reserved resources; if the numerical solution is multiple groups, determining a group of numerical solutions that meets the first condition in the multiple groups of numerical solutions as the numerical value of the frequency domain reserved resources;

[0554] Wherein, M is the extended increment of CP, and the M known data are the values ​​of the M time domain positions where the first OFDM symbol is the same as the target OFDM symbol.

[0555] Optionally, the first condition includes at least one of the following:

[0556] The moduli of all the values ​​in a set of numerical solutions are smaller than the first threshold;

[0557] The average value of the moduli of all numerical values ​​in a set of numerical solutions is less than a second threshold.

[0558] In this embodiment, taking the case where the first OFDM symbol is symbol n+1 and the target OFDM symbol is symbol n as an example, the method for the network device to determine the positions of M1 frequency domain reserved resources and the values ​​of the frequency domain reserved resources is as follows:

[0559] Assume that M1 takes the value M, and the input frequency domain data is X(n), n=0,1,…N-1;

[0560] Among them, there is M1 frequency domain data {X(k0 ),X(k 1 ),…X(k M1-1 )} does not transmit any information, that is, any value can be set to meet the requirement that the above M data sequences are the same; here k 0 ,k 1 ,…k M1-1 , is a non-repeating integer greater than or equal to 0 and less than or equal to N-1. 0 ,k 1 ,…k M1-1 The number of combinations is: That is, select the combination of M1 elements from N elements.

[0561] The other frequency domains are used to transmit data (i.e., the data in other frequency domains are fixed values ​​and cannot be changed). 0 ),X(k 1 ),…X(k M-1 )}.

[0562] According to the following IDFT formula:

[0563]

[0564] We can list M1-variable linear equations, and there are M M1-variable linear equations in total. That is, by solving M M1-variable linear equations, we can get a set of "numerical solutions".

[0565] Furthermore, due to k 0 ,k 1 ,…k M1-1 The number of combinations of is K, that is, at least K groups of “numerical solutions” can be obtained.

[0566] Find a set of "appropriate" values ​​from K sets of "numerical solutions", that is, determine the "appropriate" position and the "appropriate" value.

[0567] The solution that satisfies the "appropriate" value can be any of the following:

[0568] 1) The modulus of all M1 values ​​is less than a threshold;

[0569] 2) The average value of the modulus of M1 values ​​is less than a threshold.

[0570] It should be noted that when solving a linear equation of M1, the "numerical solution" may not be the numerical value of the solution to the equation in the mathematical sense. When the error between two numerical values ​​is within a certain range, it can be considered as the solution to the equation.

[0571] In addition to being greater than or equal to M, the value of M1 can also be less than M. Considering the randomness of the input data of OFDM symbol n+1, there may be other situations where the number of reserved resources is less than M (such as M1=0, M1=M / 2), and the above equation relationship is satisfied.

[0572] On the M1 frequency domain reserved resources, data can be transmitted in a rate matching manner (i.e., bypassing these resources when mapping data) or in a puncturing manner (i.e., data can be mapped to the reserved resources, and the receiving end considers that it is punctured);

[0573] Among the combinations of M1 frequency domain reserved resources, the combinations occupying important frequency domain positions are discarded, for example, the original RE positions are used to transmit PDCCH or DMRS.

[0574] It should be noted that, when the first OFDM symbol is symbol n and the target OFDM symbol is symbol n+1, the method for the network device to determine the positions of M1 frequency domain reserved resources and the values ​​of the frequency domain reserved resources is similar to the above method and will not be described in detail here. It should be noted that, in the case where the first OFDM symbol is an adjacent symbol before the target OFDM symbol for CP extension, the network device does not need to indicate the information of the extended increment M of the CP to the terminal, and the terminal side does not need to calculate the value; but the transmitting end needs to perform symbol reverse processing, such as processing symbol n+1 first and then symbol n. Taking into account that public signaling needs to be compatible with older versions of UE, this method can be used for sending public signaling, thereby improving the receiving performance of public signaling, such as using this method to send SSB, SIB1 information, etc.

[0575] The M1 is only related to the FFT size and CP extension, and has nothing to do with the actual number of PRBs occupied. In theory, the M1 reserved resources can be located anywhere. If optimized, the value of M1 can be less than M, or greater than or equal to M. The implementation effect is as follows: Fig.15 Assume that for symbol n-1, the CP needs to be extended by 1 FFT sample point. Then, by setting the data of "appropriate" value in the RE resource at the specific k0 position of symbol n, the effect of extending the CP of symbol n-1 from 2 FFT sample points to 3 FFT sample points can be achieved.

[0576] Optionally, the distribution of the M1 frequency domain reserved resources includes at least one of the following situations:

[0577] The M1 frequency domain reserved resources are distributed in the transmittable bandwidth;

[0578] The M1 frequency domain reserved resources are distributed in the protection bandwidth, and the signal power of the M1 frequency domain reserved resources is less than a third threshold; the third threshold can be set according to the data transmission requirement of the network device;

[0579] The M1 frequency domain reserved resources are distributed outside the bandwidth, and the signal power of the M1 frequency domain reserved resources is less than a fourth threshold, and the fourth threshold can be set according to the data transmission requirement of the network device.

[0580] In this embodiment, the M1 frequency domain reserved resources in the first OFDM symbol may be distributed in the transmittable bandwidth, in the protection bandwidth, or outside the bandwidth. In addition to traversing all positions, other methods may be used to optimize the method of determining the M1 "appropriate" frequency domain reserved resources and the "appropriate" value of the frequency domain reserved resources. The specific optimization method is as follows:

[0581] Step 61: The M1 frequency domain reserved resources are preferentially placed on the protection bandwidth and out-of-band RE resources.

[0582] In this embodiment, the M1 frequency domain reserved resources are preferentially placed on the protection bandwidth and out-of-band RE resources. The power corresponding to the set data value does not exceed the threshold range specified by the standard protocol.

[0583] Step 62: Determine the location of the frequency domain reserved resource on the communication frequency

[0584] Through step 62, a part or all of the M1 frequency domain reserved resources are preferentially determined. If the above-mentioned extended CP function can be achieved through step 62, there is no need to set reserved resources on the communication frequency, that is, there is no need to indicate the UE frequency domain reserved resource information.

[0585] The protection bandwidth in the above embodiment: In the authorized spectrum, in order to avoid frequency domain interference of adjacent channels, usually, the transmitter needs to reserve some frequency domain RE resources. The power of these frequency domain reserved resources needs to be strictly limited, that is, the power cannot exceed a certain threshold. Usually, on these reserved resources, the network equipment does not send any data information.

[0586] Regarding out-of-band leakage limitation: When the transmitter sends a signal, due to the limitation of the implementation device, the relevant signal will not only be transmitted in the communication channel but also leak out of the communication bandwidth. The leaked signal power cannot exceed a certain threshold.

[0587] It should be noted that the network device in the embodiment of the present application can implement the steps and technical effects implemented by all network devices in the above method embodiment applied to the terminal, and the same parts will not be repeated here.

[0588] In an embodiment of the present application, for the nth OFDM symbol to be transmitted, on the N REs input to the IFFT, the "appropriate" position and the "appropriate" value of the M1 RE resources are selected, so as to achieve the effect of extending the CP length of the n-1th OFDM symbol by M sample points. Alternatively, for the nth OFDM symbol to be transmitted, on the N REs input to the IFFT, the "appropriate" position and the "appropriate" value of the M1 RE resources are selected, so as to achieve the effect of extending the CP length of the n+1th OFDM symbol by M sample points.

[0589] It should be noted that the above embodiment is described with the terminal as the data receiving end and the network device as the data sending end. In practical applications, the above method of extending CP is also applicable to the transmission of uplink data, that is, the terminal is used as the data sending end and the network device is used as the data receiving end. The process of uplink data transmission is similar to the implementation process of downlink data transmission in the above embodiment. The relevant information of the extended CP and / or the information of the frequency domain reserved resources of the first OFDM symbol are configured by the network device, but the execution end of the data transmission is different, and similar contents are not repeated here.

[0590] In an embodiment of the present application, the network device indicates to the terminal the relevant information of the extended CP, so that the terminal can determine the target OFDM symbol for which the CP extension is required and the extended increment of the CP. The network device can indicate to the terminal the information of the frequency domain reserved resources of the adjacent symbols of the target OFDM symbol before the transformation is performed, so that the terminal can determine the unavailable position in the data transmission, thereby improving the data reception efficiency; the terminal can also obtain the uplink OFDM symbol to be sent based on the information of the frequency domain reserved resources, so as to achieve the effect of extending the CP without changing the physical layer frame structure. This solution achieves the effect of extending the CP without changing the physical layer frame structure, the device implementation cost is low, and it is compatible with the terminal services of the old version, which can save air interface resources.

[0591] The above embodiment introduces the method for extending the cyclic prefix of the present application. The following embodiment will further illustrate the corresponding device in conjunction with the accompanying drawings.

[0592] Specifically, Fig.23 As shown, the embodiment of the present application provides a device 2300 for extending a cyclic prefix, which is applied to a terminal, including:

[0593] The first receiving unit 2310 is configured to receive information related to an extended cyclic prefix CP sent by a network device and / or information on frequency domain reserved resources of a first OFDM symbol;

[0594] The relevant information of the extended CP is used to indicate a target OFDM symbol using the extended CP and an extended increment of the CP; the first OFDM symbol is adjacent to the target OFDM symbol;

[0595] The transmission unit 2320 is configured to perform data transmission according to the relevant information of the extended CP and / or the information of the frequency domain reserved resources of the first OFDM symbol.

[0596] Optionally, the relevant information of the extended CP includes at least one of the following:

[0597] Information indicating a target OFDM symbol using an extended CP;

[0598] Expansion increment of CP;

[0599] The extended CP length.

[0600] Optionally, the first receiving unit is specifically configured to:

[0601] A high-layer signaling and / or a scheduling signaling sent by a network device is received, where the high-layer signaling and / or the scheduling signaling carries relevant information of the extended CP and / or information of frequency domain reserved resources of the first OFDM symbol.

[0602] Optionally, the transmission unit is specifically used for:

[0603] According to the information of the frequency domain reserved resources of the first OFDM symbol, it is determined that the frequency domain reserved resources are not used for downlink transmission or uplink transmission.

[0604] Optionally, the transmission unit is specifically used for:

[0605] According to the extended increment of the CP, a starting position for receiving the target OFDM symbol is adjusted.

[0606] Optionally, the starting position for receiving the target OFDM symbol is: a position that is M time domain positions later than the receiving starting position determined by a conventional CP;

[0607] Where M is the expansion increment of CP.

[0608] It should be noted here that the above-mentioned device provided in the embodiment of the present application can implement all the method steps implemented by the above-mentioned method embodiment applied to the terminal, and can achieve the same technical effect. The parts and beneficial effects of this embodiment that are the same as the method embodiment will not be described in detail here.

[0609] Specifically, Fig.24 As shown, the embodiment of the present application provides a device 2400 for extending a cyclic prefix, which is applied to a network device, including:

[0610] The first sending unit 2410 is configured to send relevant information of an extended cyclic prefix CP and / or information of a frequency domain reserved resource of a first OFDM symbol to a terminal;

[0611] The relevant information of the extended CP is used to indicate the target OFDM symbol using the extended CP and the extended increment of the CP; and the first OFDM symbol is adjacent to the target OFDM symbol.

[0612] Optionally, the relevant information of the extended CP includes at least one of the following:

[0613] Information indicating a target OFDM symbol using an extended CP;

[0614] Expansion increment of CP;

[0615] The extended CP length.

[0616] Optionally, the first sending unit is specifically configured to:

[0617] A high-layer signaling and / or a scheduling signaling is sent to the terminal, wherein the high-layer signaling and / or the scheduling signaling carries relevant information of the extended CP and / or information of frequency domain reserved resources of the first OFDM symbol.

[0618] Optionally, the device further comprises:

[0619] A mapping unit, used for mapping the data to be sent to the frequency domain of the OFDM symbol to be sent;

[0620] A second determining unit, configured to determine, for the first OFDM symbol, a position of the frequency domain reserved resource and a value of the frequency domain reserved resource;

[0621] A transform unit, used to perform transformation to generate OFDM symbols to be transmitted;

[0622] A symbol adding unit, configured to add CPs to the OFDM symbol according to a conventional number of CPs;

[0623] The second sending unit is used to send the OFDM symbol to the terminal.

[0624] Optionally, the first OFDM symbol is an adjacent symbol after the time domain position of the target OFDM symbol, and the values ​​of the M first time domain positions of the first OFDM symbol are the same as the values ​​of the first M time domain positions of the target OFDM symbol;

[0625] or,

[0626] The first OFDM symbol is an adjacent symbol before the time domain position of the target OFDM symbol, and the values ​​of the last M time domain positions of the first OFDM symbol are the same as the values ​​of the M second time domain positions of the target OFDM symbol;

[0627] Where M is the expansion increment of CP.

[0628] Optionally, the M first time domain positions include one of the following:

[0629] The first M time domain positions of the first OFDM symbol after adding the CP according to the conventional CP number;

[0630] When M is less than or equal to A, the M first time domain positions include: a time domain position of first data and subsequent M-1 time domain positions, and the first data is: data whose sequence number is the difference between the total length of the data sequence and A;

[0631] When M is greater than A, the 1st to Ath time domain positions in M ​​are: the time domain position of the first data and the subsequent A-1 time domain positions, the first data being: data whose sequence number is the difference between the total length of the data sequence and A; the A+1th to Mth time domain positions in M ​​are: the first MA time domain positions;

[0632] Where A is the number of sample points of the conventional CP.

[0633] Optionally, the M second time domain positions include:

[0634] The difference between the total length of the data sequence and the total length of the extended CP and the time domain position of the subsequent M-1 data.

[0635] Optionally, the device further includes: a processing unit, wherein the processing unit is specifically configured to:

[0636] Select M1 frequency domain reserved resource positions from the N frequency domain positions, where M1 is greater than or equal to 0;

[0637] According to the M known data and the transformation formula, one or more sets of numerical solutions are determined, each set of numerical solutions corresponds to a resource location combination;

[0638] If the numerical solution is a group, determining the group of numerical solutions as the numerical value of the frequency domain reserved resources; if the numerical solution is multiple groups, determining a group of numerical solutions that meets the first condition in the multiple groups of numerical solutions as the numerical value of the frequency domain reserved resources;

[0639] Wherein, M is the extended increment of CP, and the M known data are the values ​​of the M time domain positions where the first OFDM symbol is the same as the target OFDM symbol.

[0640] Optionally, the first condition includes at least one of the following:

[0641] The moduli of all the values ​​in a set of numerical solutions are smaller than the first threshold;

[0642] The average value of the moduli of all numerical values ​​in a set of numerical solutions is less than a second threshold.

[0643] Optionally, the distribution of the M1 frequency domain reserved resources includes at least one of the following situations:

[0644] The M1 frequency domain reserved resources are distributed in the transmittable bandwidth;

[0645] The M1 frequency domain reserved resources are distributed in the protection bandwidth, and the signal power of the M1 frequency domain reserved resources is less than a third threshold;

[0646] The M1 frequency domain reserved resources are distributed outside the bandwidth, and signal powers of the M1 frequency domain reserved resources are less than a fourth threshold.

[0647] Optionally, the device further comprises:

[0648] A third determining unit is used to determine an expansion increment of CP, where the expansion increment of CP is an increment relative to the number of regular CPs;

[0649] The fourth determining unit is configured to determine relevant information of the extended CP according to the extended increment of the CP.

[0650] Optionally, the frequency domain reserved resources of the first OFDM symbol are not used for downlink transmission or uplink transmission.

[0651] It should be noted here that the above-mentioned device provided in the embodiment of the present application can implement all the method steps implemented by the above-mentioned method embodiment applied to the network side device, and can achieve the same technical effect. The parts and beneficial effects of this embodiment that are the same as the method embodiment will not be described in detail here.

[0652] It should be noted that the division of units in the embodiments of the present application is schematic and is only a logical function division. There may be other division methods in actual implementation. In addition, each functional unit in each embodiment of the present application may be integrated into a processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit. The above-mentioned integrated unit may be implemented in the form of hardware or in the form of software functional units.

[0653] If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a processor-readable storage medium. Based on this understanding, the technical solution of the present application is essentially or the part that contributes to the prior art or all or part of the technical solution can be embodied in the form of a software product, and the computer software product is stored in a storage medium, including a number of instructions to enable a computer device (which can be a personal computer, server, or network device, etc.) or a processor (processor) to perform all or part of the steps of the method described in each embodiment of the present application. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (Read-Only Memory, ROM), random access memory (Random Access Memory, RAM), disk or optical disk and other media that can store program codes.

[0654] like Fig.25 As shown, an embodiment of the present application further provides a terminal, including: a memory 2520, a transceiver 2500, and a processor 2510; wherein the memory 2520 is used to store a computer program; the transceiver 2500 is used to receive and send data under the control of the processor 2510; the processor 2510 is used to read the computer program in the memory and perform the following operations:

[0655] Receiving relevant information of an extended cyclic prefix CP and / or information of a frequency domain reserved resource of a first OFDM symbol sent by a network device;

[0656] The relevant information of the extended CP is used to indicate a target OFDM symbol using the extended CP and an extended increment of the CP; the first OFDM symbol is adjacent to the target OFDM symbol;

[0657] Data transmission is performed according to the relevant information of the extended CP and / or the information of the frequency domain reserved resources of the first OFDM symbol.

[0658] Optionally, the relevant information of the extended CP includes at least one of the following:

[0659] Information indicating a target OFDM symbol using an extended CP;

[0660] Expansion increment of CP;

[0661] The extended CP length.

[0662] Optionally, the processor is configured to read the computer program in the memory and perform the following operations:

[0663] A high-layer signaling and / or a scheduling signaling sent by a network device is received, where the high-layer signaling and / or the scheduling signaling carries relevant information of the extended CP and / or information of frequency domain reserved resources of the first OFDM symbol.

[0664] Optionally, the processor is configured to read the computer program in the memory and perform the following operations:

[0665] According to the information of the frequency domain reserved resources of the first OFDM symbol, it is determined that the frequency domain reserved resources are not used for downlink transmission or uplink transmission.

[0666] Optionally, the processor is configured to read the computer program in the memory and perform the following operations:

[0667] According to the extended increment of the CP, a starting position for receiving the target OFDM symbol is adjusted.

[0668] Optionally, the starting position for receiving the target OFDM symbol is: a position that is M time domain positions later than the receiving starting position determined by a conventional CP;

[0669] Where M is the expansion increment of CP.

[0670] Among them, Fig.25 In the embodiment, the bus architecture may include any number of interconnected buses and bridges, specifically one or more processors represented by processor 2510 and various circuits of memory represented by memory 2520 are linked together. The bus architecture may also link together various other circuits such as peripherals, voltage regulators, and power management circuits, which are well known in the art and are therefore not further described herein. The bus interface provides an interface. The transceiver 2500 may be a plurality of components, namely, a transmitter and a transceiver, providing a unit for communicating with various other devices on a transmission medium. For different user devices, the user interface 2530 may also be an interface capable of externally and internally connecting required devices, and the connected devices include but are not limited to a keypad, a display, a speaker, a microphone, a joystick, and the like.

[0671] The processor 2510 is responsible for managing the bus architecture and general processing, and the memory 2520 can store data used by the processor 2510 when performing operations.

[0672] Optionally, processor 2510 can be a central processing unit (CPU), an application specific integrated circuit (ASIC), a field programmable gate array (FPGA) or a complex programmable logic device (CPLD), and the processor can also adopt a multi-core architecture.

[0673] The processor calls the computer program stored in the memory to execute any of the methods provided in the embodiments of the present application according to the obtained executable instructions. The processor and the memory can also be arranged physically separately.

[0674] It should be noted here that the above-mentioned terminal provided in the embodiment of the present application can implement all the method steps implemented by the above-mentioned method embodiment applied to the terminal, and can achieve the same technical effect. The parts and beneficial effects of this embodiment that are the same as the method embodiment will not be described in detail here.

[0675] like Fig.26 As shown, an embodiment of the present application further provides a network device, including: a memory 2620, a transceiver 2600, and a processor 2610; wherein the memory 2620 is used to store a computer program; the transceiver 2600 is used to receive and send data under the control of the processor 2610; the processor 2610 is used to read the computer program in the memory and perform the following operations:

[0676] Sending relevant information of the extended cyclic prefix CP and / or information of the frequency domain reserved resources of the first OFDM symbol to the terminal;

[0677] The relevant information of the extended CP is used to indicate the target OFDM symbol using the extended CP and the extended increment of the CP; and the first OFDM symbol is adjacent to the target OFDM symbol.

[0678] Optionally, the relevant information of the extended CP includes at least one of the following:

[0679] Information indicating a target OFDM symbol using an extended CP;

[0680] Expansion increment of CP;

[0681] The extended CP length.

[0682] Optionally, the processor is configured to read the computer program in the memory and perform the following operations:

[0683] A high-layer signaling and / or a scheduling signaling is sent to the terminal, wherein the high-layer signaling and / or the scheduling signaling carries relevant information of the extended CP and / or information of frequency domain reserved resources of the first OFDM symbol.

[0684] Optionally, the processor is configured to read the computer program in the memory and perform the following operations:

[0685] Mapping the data to be sent to the frequency domain of the OFDM symbol to be sent;

[0686] For the first OFDM symbol, determining a position of the frequency domain reserved resource and a value of the frequency domain reserved resource;

[0687] Performing transformation to generate OFDM symbols to be transmitted;

[0688] Adding CPs to the OFDM symbol according to a conventional number of CPs;

[0689] The OFDM symbol is sent to a terminal.

[0690] Optionally, the first OFDM symbol is an adjacent symbol after the time domain position of the target OFDM symbol, and the values ​​of the M first time domain positions of the first OFDM symbol are the same as the values ​​of the first M time domain positions of the target OFDM symbol;

[0691] or,

[0692] The first OFDM symbol is an adjacent symbol before the time domain position of the target OFDM symbol, and the values ​​of the last M time domain positions of the first OFDM symbol are the same as the values ​​of the M second time domain positions of the target OFDM symbol;

[0693] Where M is the expansion increment of CP.

[0694] Optionally, the M first time domain positions include one of the following:

[0695] The first M time domain positions of the first OFDM symbol after adding the CP according to the conventional CP number;

[0696] When M is less than or equal to A, the M first time domain positions include: a time domain position of first data and subsequent M-1 time domain positions, and the first data is: data whose sequence number is the difference between the total length of the data sequence and A;

[0697] When M is greater than A, the 1st to Ath time domain positions in M ​​are: the time domain position of the first data and the subsequent A-1 time domain positions, the first data being: data whose sequence number is the difference between the total length of the data sequence and A; the A+1th to Mth time domain positions in M ​​are: the first MA time domain positions;

[0698] Where A is the number of sample points of the conventional CP.

[0699] Optionally, the M second time domain positions include:

[0700] The difference between the total length of the data sequence and the total length of the extended CP and the time domain position of the subsequent M-1 data.

[0701] Optionally, the processor is configured to read the computer program in the memory and perform the following operations:

[0702] Select M1 frequency domain reserved resource positions from N frequency domain positions, where M1 is greater than or equal to 0; determine one or more sets of numerical solutions based on the M known data and the transformation formula, where each set of numerical solutions corresponds to a resource position combination;

[0703] If the numerical solution is a group, determining the group of numerical solutions as the numerical value of the frequency domain reserved resources; if the numerical solution is multiple groups, determining a group of numerical solutions that meets the first condition in the multiple groups of numerical solutions as the numerical value of the frequency domain reserved resources;

[0704] Wherein, M is the extended increment of CP, and the M known data are the values ​​of the M time domain positions where the first OFDM symbol is the same as the target OFDM symbol.

[0705] Optionally, the first condition includes at least one of the following:

[0706] The moduli of all the values ​​in a set of numerical solutions are smaller than the first threshold;

[0707] The average value of the moduli of all numerical values ​​in a set of numerical solutions is less than a second threshold.

[0708] Optionally, the distribution of the M1 frequency domain reserved resources includes at least one of the following situations:

[0709] The M1 frequency domain reserved resources are distributed in the transmittable bandwidth;

[0710] The M1 frequency domain reserved resources are distributed in the protection bandwidth, and the signal power of the M1 frequency domain reserved resources is less than a third threshold;

[0711] The M1 frequency domain reserved resources are distributed outside the bandwidth, and signal powers of the M1 frequency domain reserved resources are less than a fourth threshold.

[0712] Optionally, the processor is configured to read the computer program in the memory and perform the following operations:

[0713] Determining an expansion increment of the CP, wherein the expansion increment of the CP is an increment relative to the number of regular CPs;

[0714] The relevant information of the extended CP is determined according to the extended increment of the CP.

[0715] Optionally, the frequency domain reserved resources of the first OFDM symbol are not used for downlink transmission or uplink transmission.

[0716] Among them, Fig.26 In the embodiment, the bus architecture may include any number of interconnected buses and bridges, specifically one or more processors represented by processor 2610 and various circuits of memory represented by memory 2620 are linked together. The bus architecture may also link together various other circuits such as peripherals, voltage regulators, and power management circuits, which are well known in the art and are therefore not further described herein. The bus interface provides an interface. The transceiver 2600 may be a plurality of components, namely, a transmitter and a transceiver, providing a unit for communicating with various other devices on a transmission medium. The processor 2610 is responsible for managing the bus architecture and general processing, and the memory 2620 may store data used by the processor 2610 when performing operations.

[0717] The processor 2610 may be a central processing unit (CPU), an application specific integrated circuit (ASIC), a field programmable gate array (FPGA) or a complex programmable logic device (CPLD). The processor may also adopt a multi-core architecture.

[0718] It should be noted here that the above-mentioned network device provided in the embodiment of the present application can implement all the method steps implemented by the above-mentioned method embodiment applied to the network side device, and can achieve the same technical effect. The parts and beneficial effects that are the same as the method embodiment in this embodiment will not be described in detail here.

[0719] In addition, a specific embodiment of the present application also provides a processor-readable storage medium on which a computer program is stored, wherein when the program is executed by the processor, the steps of the method for extending the cyclic prefix applied to the terminal as described above are implemented, and the same technical effect can be achieved. To avoid repetition, it will not be repeated here.

[0720] A specific embodiment of the present application also provides a processor-readable storage medium on which a computer program is stored, wherein when the program is executed by the processor, the steps of the method for extending the cyclic prefix applied to a network device as described above are implemented, and the same technical effect can be achieved. To avoid repetition, it will not be repeated here.

[0721] Among them, the readable storage medium can be any available medium or data storage device that can be accessed by the processor, including but not limited to magnetic storage (such as floppy disks, hard disks, magnetic tapes, magneto-optical disks (MO), etc.), optical storage (such as CD, DVD, BD, HVD, etc.), and semiconductor storage (such as ROM, EPROM, EEPROM, non-volatile memory (NANDFLASH), solid-state drive (SSD)), etc.

[0722] It should be noted that the technical solution provided in the embodiment of the present application can be applicable to a variety of systems, especially 5G systems. For example, the applicable system can be a global system of mobile communication (GSM) system, a code division multiple access (CDMA) system, a wideband code division multiple access (WCDMA) general packet radio service (GPRS) system, a long term evolution (LTE) system, a LTE frequency division duplex (FDD) system, a LTE time division duplex (TDD) system, an advanced long term evolution (LTE-A) system, a universal mobile telecommunication system (UMTS), a world-wide interoperability for microwave access (WiMAX) system, a 5G new radio (NR) system, etc. These various systems include terminal equipment and network equipment. The system may also include a core network part, such as an evolved packet system (EPS), a 5G system (5GS), etc.

[0723] The terminal device involved in the embodiment of the present application may be a device that provides voice and / or data connectivity to a user, a handheld device with a wireless connection function, or other processing devices connected to a wireless modem. In different systems, the name of the terminal device may also be different. For example, in a 5G system, the terminal device may be called a user equipment (UE). A wireless terminal device can communicate with one or more core networks (CN) via a radio access network (RAN). The wireless terminal device may be a mobile terminal device, such as a mobile phone (or a "cellular" phone) and a computer with a mobile terminal device. For example, it may be a portable, pocket-sized, handheld, computer-built-in or vehicle-mounted mobile device that exchanges language and / or data with a wireless access network. For example, personal communication service (PCS) phones, cordless phones, session initiation protocol (SIP) phones, wireless local loop (WLL) stations, personal digital assistants (PDAs) and other devices. The wireless terminal device may also be referred to as a system, a subscriber unit, a subscriber station, a mobile station, a mobile station, a remote station, an access point, a remote terminal device, an access terminal device, a user terminal device, a user agent, and a user device, but is not limited in the embodiments of the present application.

[0724] The network device involved in the embodiment of the present application may be a base station, which may include multiple cells providing services for the terminal. Depending on the specific application scenario, the base station may also be called an access point, or may be a device in the access network that communicates with the wireless terminal device through one or more sectors on the air interface, or other names. The network device may be used to interchange received air frames with Internet Protocol (IP) packets, and serve as a router between the wireless terminal device and the rest of the access network, wherein the rest of the access network may include an Internet Protocol (IP) communication network. The network device may also coordinate the attribute management of the air interface. For example, the network device involved in the embodiments of the present application may be a network device (Base Transceiver Station, BTS) in the Global System for Mobile communications (Global System for Mobile communications, GSM) or Code Division Multiple Access (Code Division Multiple Access, CDMA), or a network device (NodeB) in Wide-band Code Division Multiple Access (WCDMA), or an evolutionary network device (evolutional Node B, eNB or e-NodeB) in the long term evolution (long term evolution, LTE) system, a 5G base station (gNB) in the 5G network architecture (next generation system), or a home evolved Node B (Home evolved Node B, HeNB), a relay node, a home base station (femto), a pico base station (pico), etc., which is not limited in the embodiments of the present application. In some network structures, the network device may include a centralized unit (CU) node and a distributed unit (DU) node, and the centralized unit and the distributed unit may also be arranged geographically separately.

[0725] Network devices and terminal devices can each use one or more antennas for multiple-input multiple-output (MIMO) transmission. MIMO transmission can be single-user MIMO (SU-MIMO) or multi-user MIMO (MU-MIMO). Depending on the form and number of antenna combinations, MIMO transmission can be 2D-MIMO, 3D-MIMO, FD-MIMO or massive-MIMO, or it can be diversity transmission, precoded transmission or beamforming transmission, etc.

[0726] Those skilled in the art will appreciate that the embodiments of the present application may be provided as methods, systems, or computer program products. Therefore, the present application may adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment in combination with software and hardware. Moreover, the present application may adopt the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage and optical storage, etc.) that contain computer-usable program code.

[0727] The present application is described with reference to the flowchart and / or block diagram of the method, device (system) and computer program product according to the embodiment of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, and the combination of the process and / or box in the flowchart and / or block diagram can be implemented by computer executable instructions. These computer executable instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device produce a device for implementing a process or multiple processes in the flowchart and / or a box or multiple boxes in the block diagram.

[0728] These processor-executable instructions may also be stored in a processor-readable memory that can direct a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the processor-readable memory produce a product including an instruction device that implements the functions specified in one or more processes in the flowchart and / or one or more boxes in the block diagram.

[0729] These processor-executable instructions may also be loaded onto a computer or other programmable data processing device so that a series of operational steps are performed on the computer or other programmable device to produce a computer-implemented process, whereby the instructions executed on the computer or other programmable device provide steps for implementing the functions specified in one or more processes in the flowchart and / or one or more boxes in the block diagram.

[0730] Obviously, those skilled in the art can make various changes and modifications to the present application without departing from the spirit and scope of the present application. Thus, if these modifications and variations of the present application fall within the scope of the claims of the present application and their equivalents, the present application is also intended to include these modifications and variations.

Claims

1. A method for extending a cyclic prefix, characterized in that: include: The terminal receives relevant information of the extended cyclic prefix CP and / or information of the frequency domain reserved resources of the first OFDM symbol sent by the network device; The relevant information of the extended CP is used to indicate a target OFDM symbol using the extended CP and an extended increment of the CP; the first OFDM symbol is adjacent to the target OFDM symbol; The terminal performs data transmission according to the relevant information of the extended CP and / or the information of the frequency domain reserved resource of the first OFDM symbol.

2. The method according to claim 1, characterized in that The relevant information of the extended CP includes at least one of the following: Information indicating a target OFDM symbol using an extended CP; Expansion increment of CP; The extended CP length.

3. The method according to claim 1, characterized in that The receiving network device sends the related information of the extended cyclic prefix CP and / or the information of the frequency domain reserved resources of the first OFDM symbol, including: A high-layer signaling and / or a scheduling signaling sent by a network device is received, where the high-layer signaling and / or the scheduling signaling carries relevant information of the extended CP and / or information of frequency domain reserved resources of the first OFDM symbol.

4. The method according to claim 1, characterized in that: The performing of data transmission according to the information of the frequency domain reserved resource of the first OFDM symbol comprises: According to the information of the frequency domain reserved resources of the first OFDM symbol, it is determined that the frequency domain reserved resources are not used for downlink transmission or uplink transmission.

5. The method according to claim 1, characterized in that Perform data transmission according to the relevant information of the extended CP, including: According to the extended increment of the CP, a starting position for receiving the target OFDM symbol is adjusted.

6. The method according to claim 5, characterized in that The starting position for receiving the target OFDM symbol is: a position that is M time domain positions later than the receiving starting position determined by a conventional CP; wherein M is an extended increment of the CP.

7. A method for extending a cyclic prefix, characterized in that: include: The network device sends relevant information of the extended cyclic prefix CP and / or information of the frequency domain reserved resources of the first OFDM symbol to the terminal; The related information of the extended CP is used to indicate the target OFDM symbol using the extended CP and the extended increment of the CP; The first OFDM symbol is adjacent to the target OFDM symbol.

8. The method according to claim 7, characterized in that The sending the relevant information of the extended cyclic prefix CP and / or the information of the frequency domain reserved resources of the first OFDM symbol to the terminal includes: A high-layer signaling and / or a scheduling signaling is sent to the terminal, wherein the high-layer signaling and / or the scheduling signaling carries relevant information of the extended CP and / or information of frequency domain reserved resources of the first OFDM symbol.

9. The method according to claim 7, characterized in that: The first OFDM symbol is an adjacent symbol after the time domain position of the target OFDM symbol, and the values ​​of the M first time domain positions of the first OFDM symbol are the same as the values ​​of the first M time domain positions of the target OFDM symbol; or, The first OFDM symbol is an adjacent symbol before the time domain position of the target OFDM symbol, and the values ​​of the last M time domain positions of the first OFDM symbol are the same as the values ​​of the M second time domain positions of the target OFDM symbol; Where M is the expansion increment of CP.

10. The method according to claim 9, characterized in that The M first time domain positions include one of the following: The first M time domain positions of the first OFDM symbol after adding the CP according to the conventional CP number; When M is less than or equal to A, the M first time domain positions include: a time domain position of first data and subsequent M-1 time domain positions, and the first data is: data whose sequence number is the difference between the total length of the data sequence and A; When M is greater than A, the 1st to Ath time domain positions in M ​​are: the time domain position of the first data and the subsequent A-1 time domain positions, the first data being: data whose sequence number is the difference between the total length of the data sequence and A; the A+1th to Mth time domain positions in M ​​are: the first MA time domain positions; Where A is the number of sample points of the conventional CP.

11. The method according to claim 9, characterized in that The M second time domain positions include: The difference between the total length of the data sequence and the total length of the extended CP and the time domain position of the subsequent M-1 data.

12. The method according to claim 7, characterized in that The method further comprises: Select M1 frequency domain reserved resource positions from the N frequency domain positions, where M1 is greater than or equal to 0; According to the M known data and the transformation formula, one or more sets of numerical solutions are determined, each set of numerical solutions corresponds to a resource location combination; If the numerical solution is a group, determining the group of numerical solutions as the numerical value of the frequency domain reserved resources; if the numerical solution is multiple groups, determining a group of numerical solutions that meets the first condition in the multiple groups of numerical solutions as the numerical value of the frequency domain reserved resources; Wherein, M is the extended increment of CP, and the M known data are the values ​​of the M time domain positions where the first OFDM symbol is the same as the target OFDM symbol.

13. The method according to claim 12, characterized in that The first condition includes at least one of the following: The moduli of all the values ​​in a set of numerical solutions are smaller than the first threshold; The average value of the moduli of all numerical values ​​in a set of numerical solutions is less than a second threshold.

14. The method according to claim 12, characterized in that The distribution of the M1 frequency domain reserved resources includes at least one of the following situations: The M1 frequency domain reserved resources are distributed in the transmittable bandwidth; The M1 frequency domain reserved resources are distributed in the protection bandwidth, and the signal power of the M1 frequency domain reserved resources is less than a third threshold; The M1 frequency domain reserved resources are distributed outside the bandwidth, and signal powers of the M1 frequency domain reserved resources are less than a fourth threshold.

15. The method according to claim 7, characterized in that The method further comprises: Determining an expansion increment of the CP, wherein the expansion increment of the CP is an increment relative to the number of regular CPs; The relevant information of the extended CP is determined according to the extended increment of the CP.

16. The method according to claim 7, characterized in that The frequency domain reserved resources of the first OFDM symbol are not used for downlink transmission or uplink transmission.

17. A terminal, characterized in that: include: Memory, transceiver, processor: Memory for storing computer programs; a transceiver for receiving and sending data under the control of the processor; A processor is configured to read the computer program in the memory and perform the following operations: Receiving information related to the extended CP and / or information on frequency domain reserved resources of the first OFDM symbol sent by the network device; The relevant information of the extended CP is used to indicate a target OFDM symbol using the extended CP and an extended increment of the CP; the first OFDM symbol is adjacent to the target OFDM symbol; Data transmission is performed according to the relevant information of the extended CP and / or the information of the frequency domain reserved resources of the first OFDM symbol.

18. The terminal according to claim 17, characterized in that: The processor is configured to read the computer program in the memory and perform the following operations: According to the information of the frequency domain reserved resources of the first OFDM symbol, it is determined that the frequency domain reserved resources are not used for downlink transmission or uplink transmission.

19. The terminal according to claim 17, characterized in that: The processor is configured to read the computer program in the memory and perform the following operations: According to the extended increment of the CP, a starting position for receiving the target OFDM symbol is adjusted.

20. The terminal according to claim 19, characterized in that The starting position for receiving the target OFDM symbol is: a position that is extended M time domain positions backward from the receiving starting position determined by the conventional CP; Where M is the expansion increment of CP.

21. A network device, characterized in that: include: Memory, transceiver, processor: Memory for storing computer programs; a transceiver for receiving and sending data under the control of the processor; A processor is configured to read the computer program in the memory and perform the following operations: Sending relevant information of the extended cyclic prefix CP and / or information of the frequency domain reserved resources of the first OFDM symbol to the terminal; The related information of the extended CP is used to indicate the target OFDM symbol using the extended CP and the extended increment of the CP; The first OFDM symbol is adjacent to the target OFDM symbol.

22. The network device according to claim 21, characterized in that: The first OFDM symbol is an adjacent symbol after the time domain position of the target OFDM symbol, and the values ​​of the M first time domain positions of the first OFDM symbol are the same as the values ​​of the first M time domain positions of the target OFDM symbol; or, The first OFDM symbol is an adjacent symbol before the time domain position of the target OFDM symbol, and the values ​​of the last M time domain positions of the first OFDM symbol are the same as the values ​​of the M second time domain positions of the target OFDM symbol; Where M is the expansion increment of CP.

23. The network device according to claim 22, characterized in that: The M first time domain positions include one of the following: The first M time domain positions of the first OFDM symbol after adding the CP according to the conventional CP number; When M is less than or equal to A, the M first time domain positions include: a time domain position of first data and subsequent M-1 time domain positions, and the first data is: data whose sequence number is the difference between the total length of the data sequence and A; When M is greater than A, the 1st to Ath time domain positions in M ​​are: the time domain position of the first data and the subsequent A-1 time domain positions, the first data being: data whose sequence number is the difference between the total length of the data sequence and A; the A+1th to Mth time domain positions in M ​​are: the first MA time domain positions; Where A is the number of sample points of the conventional CP.

24. The network device according to claim 22, characterized in that: The M second time domain positions include: The difference between the total length of the data sequence and the total length of the extended CP and the time domain position of the subsequent M-1 data.

25. The network device according to claim 21, characterized in that The processor is configured to read the computer program in the memory and perform the following operations: Select M1 frequency domain reserved resource positions from the N frequency domain positions, where M1 is greater than or equal to 0; According to the M known data and the transformation formula, one or more sets of numerical solutions are determined, each set of numerical solutions corresponds to a resource location combination; If the numerical solution is a group, determining the group of numerical solutions as the numerical value of the frequency domain reserved resources; if the numerical solution is multiple groups, determining a group of numerical solutions that meets the first condition in the multiple groups of numerical solutions as the numerical value of the frequency domain reserved resources; Wherein, M is the extended increment of CP, and the M known data are the values ​​of the M time domain positions where the first OFDM symbol is the same as the target OFDM symbol.

26. The network device according to claim 21, characterized in that The processor is configured to read the computer program in the memory and perform the following operations: Determining an expansion increment of the CP, wherein the expansion increment of the CP is an increment relative to the number of regular CPs; The relevant information of the extended CP is determined according to the extended increment of the CP.

27. A device for extending a cyclic prefix, characterized in that: include: A first receiving unit, configured to receive relevant information of an extended cyclic prefix CP sent by a network device, and / or information of a frequency domain reserved resource of a first OFDM symbol; The relevant information of the extended CP is used to indicate a target OFDM symbol using the extended CP and an extended increment of the CP; the first OFDM symbol is adjacent to the target OFDM symbol; The transmission unit is used to perform data transmission according to the relevant information of the extended CP and / or the information of the frequency domain reserved resources of the first OFDM symbol.

28. A device for extending a cyclic prefix, characterized in that: include: A first sending unit, configured to send relevant information of an extended cyclic prefix CP and / or information of a frequency domain reserved resource of a first OFDM symbol to a terminal; The related information of the extended CP is used to indicate the target OFDM symbol using the extended CP and the extended increment of the CP; The first OFDM symbol is adjacent to the target OFDM symbol.

29. A processor-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the computer program implements the steps of the method for extending a cyclic prefix according to any one of claims 1 to 6; or implements the steps of the method for extending a cyclic prefix according to any one of claims 7 to 16.

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