CN108366375B

CN108366375B - Method and device for sharing downlink frequency spectrum

Info

Publication number: CN108366375B
Application number: CN201710057602.4A
Authority: CN
Inventors: 王新征
Original assignee: Huawei Technologies Co Ltd
Current assignee: Huawei Technologies Co Ltd
Priority date: 2017-01-26
Filing date: 2017-01-26
Publication date: 2021-09-14
Anticipated expiration: 2037-01-26
Also published as: CN108366375A

Abstract

The application provides a method and a device for sharing a downlink frequency spectrum, belonging to the technical field of communication. The method comprises the following steps: when the data transmission quantity of a target Long Term Evolution (LTE) cell is lower than a preset threshold value, a base station determines at least one non-scheduled non-multimedia broadcast multicast single frequency network (MBSFN) subframe of the target LTE cell; the base station maps the reference signal of the target LTE cell to the resource unit RE of the LTE reference signal in the at least one non-MBSFN subframe; the base station maps data to be sent of a target new wireless NR cell to REs except for REs of the LTE reference signal in the at least one non-MBSFN subframe; and the base station transmits the reference signal and the data to be transmitted through the at least one non-MBSFN subframe. By the method and the device, the data transmission efficiency of the LTE cell can be higher.

Description

Method and device for sharing downlink frequency spectrum

Technical Field

The present application relates to the field of communications technologies, and in particular, to a method and an apparatus for sharing a downlink spectrum.

Background

A New Radio (NR) technology in a fifth generation mobile communication technology (5G) is similar to a Long Term Evolution (LTE) technology in a fourth generation mobile communication technology (4G), and is also an air interface technology having a time-Frequency structure, in which, even when using a Frequency resource, a time dimension is divided into different Orthogonal Frequency Division Multiplexing (OFDM) symbols, and a Frequency dimension is divided into different subcarriers.

In the prior art, when the downlink spectrum is shared by the LTE cell and the NR cell, the general base station is a dual-system base station and supports simultaneous data transmission between the LTE cell and the NR cell. If the data transmission amount of the NR cell is relatively high in a certain period of time, and the data transmission amount of the LTE cell is relatively low, the LTE cell may share one or more carriers for the NR cell.

However, when the LTE cell shares the carrier to the NR cell for use, the transmission resource shared to the NR cell at a time is relatively large, which may cause the transmission resource of the LTE cell to be deficient, and thus cause the efficiency of transmitting data in the LTE cell to be low.

Disclosure of Invention

In order to solve the problem in the prior art, embodiments of the present invention provide a method and an apparatus for sharing a downlink spectrum. The technical scheme is as follows:

in a first aspect, a method for sharing a downlink spectrum is provided, where the method includes:

when the data transmission quantity of the target LTE cell is lower than a preset threshold value, the base station determines at least one non-MBSFN subframe which is not scheduled in the target LTE cell, the base station maps the reference signal of the target LTE cell to the RE of the LTE reference signal in the at least one non-MBSFN subframe, the base station maps the data to be transmitted of the target new NR cell to the RE except the RE of the LTE reference signal in the at least one non-MBSFN subframe, and the base station transmits the reference signal and the data to be transmitted through the at least one non-MBSFN subframe.

The base station is a dual-mode base station and can be used for transmitting data to a terminal of a target LTE Cell and a terminal of a target NR Cell, the target LTE Cell and the target NR Cell have the same coverage range and overlapped frequency spectrums, and a Reference Signal of the target LTE Cell refers to a Cell-specific Reference Signal (CRS).

According to the scheme shown in the embodiment of the invention, a base station can detect the data transmission quantity of a target LTE cell, when the data transmission quantity of the target LTE cell is lower than a preset threshold value, the base station can share at least one non-MBSFN subframe which is not scheduled in the target LTE cell to a target NR cell, the base station determines a reference signal of the target LTE cell, then the reference signal of the target LTE cell is mapped to Resource Elements (REs) of the LTE reference signal of the MBSFN subframe, and the data to be transmitted of the target NR cell is mapped to the REs except the REs of the LTE reference signal. And then transmitting the data to be transmitted of the reference signal through the non-MBSFN subframe. The terminal of the target LTE cell can acquire the reference signal of the target LTE cell from the non-MBSFN subframe to perform radio resource measurement and channel estimation, and the terminal of the target NR cell can acquire the reference signal of the target LTE cell from the non-MBSFN subframe to perform channel estimation as the reference signal thereof to obtain a channel matrix, and then analyzes data sent by the base station from the non-MBSFN subframe.

In one possible implementation, the base station maps the data to be transmitted of the target NR cell to REs in the data region of the at least one non-MBSFN subframe except for REs of the LTE reference signal.

According to the scheme shown in the embodiment of the invention, the non-MBSFN subframe comprises a data area and a control area, wherein the data area can be used for transmitting data and reference signals, and the control area is only used for transmitting the reference signals and control information.

The data to be transmitted of the target NR cell may be applicable only to the data region of the non-MBSFN subframe.

In a possible implementation manner, the base station may perform linear transformation on the reference signal of the target LTE cell based on a preset linear general formula, where the preset linear general formula is a unitary matrix and the moduli of the elements are equal.

Wherein the preset linear general formula is set by a technician and stored in the base station, the preset linear general formula is a unitary matrix, and the modulus of each element is equal, such as

And the like.

According to the scheme disclosed by the embodiment of the invention, after the base station maps the reference signal of the target LTE cell to the RE of the LTE reference signal, the reference signal of the target LTE cell is subjected to linear transformation based on a preset linear general formula, and the reference signal after the linear transformation is the reference signal sent by the base station.

In a possible implementation manner, the base station may perform linear transformation on the to-be-transmitted data and the reference signal mapped in the non-MBSFN subframe of the target LTE cell based on a preset linear general formula.

According to the scheme shown in the embodiment of the invention, the reference signal sent by at least one non-MBSFN subframe is a reference signal subjected to linear transformation, the reference signal received by the terminal of the target LTE cell is a reference signal subjected to linear transformation, and the terminal of the target LTE cell uses the reference signal subjected to linear transformation to perform channel estimation and radio resource measurement, so that the obtained channel matrix is not original H but multiplied by a linear general formula P to be converted into H P. Since P is a unitary matrix, H is the same as the statistical property of H × P, and H × P is an equivalent channel matrix of H, the terminal of the target LTE cell can analyze data using H × P.

In the scheme shown in the embodiment of the invention, a base station determines a reference signal of a target NR cell, and maps the reference signal of the target NR cell to RE of an NR reference signal in at least one non-MBSFN subframe; and the base station maps the data to be transmitted of the target NR cell to the REs except for the REs of the LTE reference signal and the NR reference signal in at least one non-MBSFN subframe.

In a possible implementation, The reference signal of The target NR cell may also be transmitted on a non-MBSFN subframe, so that although The overhead of The reference signal becomes large, with The development of The third Generation technical specification (3 GPP), The target NR cell may schedule a smaller time slot to transmit data, such as 4 symbols, and in The scheduled small time slot, The reference signal must be mapped for The terminal of The target NR cell to perform channel estimation, so The reference signal of The target NR cell is mapped in The non-MBSFN subframe. Correspondingly, the data to be transmitted of the target NR cell is mapped to REs except REs of the LTE reference signal and the NR reference signal in at least one non-MBSFN subframe.

In the scheme shown in the embodiment of the invention, the intervals of the subcarriers of the target NR cell and the target LTE cell are the same, and the lengths of the OFDM symbols are the same.

In the scheme shown in the embodiment of the invention, the base station transmits the reference signal and the data to be transmitted through at least one non-MBSFN subframe by using a transmission mode of the transmission diversity.

In a possible implementation manner, the transmission mode of the transmit diversity refers to that the same reference signal and data to be transmitted are transmitted at different antenna ports, so that even if the terminal of the target NR cell does not receive the reference signal and the data to be transmitted at the first antenna port, the reference signal and the data to be transmitted at the second antenna port can be received, and the success rate of receiving data by the terminal of the target NR cell can be improved.

In the scheme shown in the embodiment of the invention, in at least one non-MBSFN subframe, the center frequency of all subcarriers corresponding to all REs to which the data to be sent of any terminal in the target NR cell is mapped is greater than or less than the center frequency of the direct current DC subcarrier of the target LTE cell.

Among them, a Direct Current (DC) subcarrier is a subcarrier at a carrier center position and cannot be used for transmitting a reference signal and data.

In a possible implementation manner, since the reference signals of the target NR cell are generally at equal subcarrier intervals, if there is a DC subcarrier among all REs to which data to be transmitted corresponding to any terminal in the NR cell is mapped, the interval of the reference signals of the target NR cell is increased by one subcarrier, the base station needs to transmit control information to notify that the interval of the reference signals of the terminal of the target NR cell has changed, and thus, if all REs to which data to be transmitted corresponding to any terminal in the target NR cell is mapped do not cross the DC subcarrier, the base station does not need to transmit the control information to notify that the interval of the reference signals of the terminal of the target NR cell has changed. Thereby saving transmission resources.

According to the scheme disclosed by the embodiment of the invention, the DC subcarrier of the target LTE cell is not overlapped with the DC subcarrier of the target NR cell; the center frequency of the subcarrier corresponding to the reference signal of the target LTE cell is not equal to the center frequency of the DC subcarrier of the target NR cell.

In a possible implementation manner, when the base station is set up, a Physical Cell Identifier (PCI) of the target LTE Cell is set, so that the reference signal of the target LTE Cell cannot be mapped to the DC subcarrier, and therefore when the DC subcarrier of the target LTE Cell overlaps with the DC subcarrier of the target NR Cell, the reference signal of the target LTE Cell cannot be mapped to the DC subcarrier with certainty. However, if the DC subcarrier of the target LTE cell does not overlap the DC subcarrier of the target NR cell, the base station sets up a suitable PCI of the target LTE cell so that the reference signal of the target LTE cell is not mapped onto the DC subcarrier of the target NR cell, even if the center frequency of the subcarrier corresponding to the reference signal of the target LTE cell is not equal to the center frequency of the DC subcarrier of the target NR cell.

According to the scheme shown in the embodiment of the invention, the antenna ports of the target LTE cell are a first antenna port and a second antenna port, and the antenna ports of the target NR cell are a first antenna port, a second antenna port, a third antenna port and a fourth antenna port; for the first antenna port and the second antenna port, the base station maps the reference signal of the target LTE cell to the RE of the LTE reference signal in at least one non-MBSFN subframe; for the third antenna port and the fourth antenna port, the base station determines a reference signal of a target NR cell, and maps the reference signal of the target NR cell to RE of the NR reference signal in at least one non-MBSFN subframe; for the first antenna port and the second antenna port, the base station maps the data to be sent of the target new wireless NR cell to the REs except for the RE of the LTE reference signal in at least one non-MBSFN subframe, and for the third antenna port and the fourth antenna port, the base station maps the data to be sent of the target NR cell to the REs except for the RE of the NR reference signal in at least one non-MBSFN subframe.

In a possible implementation manner, when the target LTE cell corresponds to two antenna ports, and the target NR cell corresponds to four antenna ports, for the first antenna port and the second antenna port, the base station may map the reference signal of the target LTE cell to REs of the LTE reference signal in at least one non-MBSFN subframe, and for the third antenna port and the fourth antenna port, the base station may map the reference signal of the target NR cell to REs of the NR reference signal in at least one non-MBSFN subframe.

Correspondingly, for the first antenna port and the second antenna port, the base station maps the data to be transmitted of the target new wireless NR cell to REs except for REs of the LTE reference signal in at least one non-MBSFN subframe, and for the third antenna port and the fourth antenna port, the base station maps the data to be transmitted of the target NR cell to REs except for REs of the NR reference signal in at least one non-MBSFN subframe.

In the scheme shown in the embodiment of the present invention, a base station continuously schedules a plurality of non-MBSFN subframes for a terminal of a target NR cell, and when performing channel estimation, the terminal of the target NR cell assumes that a channel remains unchanged within a length of a preset number of OFDM symbols, if two non-MBSFN subframes are continuously scheduled, 4 consecutive OFDM symbols are divided into a group, and reference signals are present on REs of a first OFDM symbol and a fourth OFDM symbol, reference signals on REs of the first OFDM symbol and the fourth OFDM symbol may be used to determine reference signals of the first OFDM symbol and the fourth OFDM symbol, and then channel estimation is performed, and if values of reference signals on REs of the first OFDM symbol and the fourth OFDM symbol in a group of OFDM symbols are taken as reference signals of channels in which the second OFDM symbol and the third OFDM symbol are respectively located, an average value is calculated.

In a second aspect, a base station is provided, where the base station includes a processor and a transmitter, and the processor implements the method for sharing a downlink spectrum provided in the first aspect by executing instructions.

In a third aspect, an apparatus for sharing a downlink spectrum is provided, where the apparatus includes at least one module, and the at least one module is configured to implement the method for sharing a downlink spectrum provided in the first aspect.

In a fourth aspect, a computer program product containing instructions is provided, which when run on a base station, causes the base station to perform the method for sharing a downlink spectrum provided in the first aspect.

The technical scheme provided by the embodiment of the invention has the following beneficial effects:

in the embodiment of the invention, a base station can detect the data transmission quantity of a target LTE cell, when the data transmission quantity of the target LTE cell is lower than a preset threshold value, the base station can determine at least one non-MBSFN subframe which is not scheduled in the target LTE cell, the base station maps a reference signal of the target LTE cell to a resource unit (RE) of the LTE reference signal in the at least one non-MBSFN subframe, maps data to be transmitted of a target NR cell to REs except the RE of the LTE reference signal in the at least one non-MBSFN subframe, and then the base station transmits the reference signal and the data to be transmitted through the at least one non-MBSFN subframe. Therefore, the base station can share the non-MBSFN subframe which is not scheduled by the target LTE cell to the target NR cell for use, so that the transmission resource shared to the target NR cell at a time is less, the transmission resource of the target LTE cell is not lacked, and the efficiency of transmitting data by the target LTE cell is higher.

Drawings

Fig. 1 is a schematic structural diagram of a system for sharing a downlink spectrum according to an embodiment of the present invention;

fig. 2 is a schematic structural diagram of a base station according to an embodiment of the present invention;

fig. 3 is a schematic flow chart of sharing a downlink spectrum according to an embodiment of the present invention;

fig. 4 is a schematic diagram of a reference signal of a target NR cell according to an embodiment of the present invention;

FIG. 5 is a schematic diagram of the change of the reference signal before and after linear transformation according to an embodiment of the present invention;

FIG. 6 is a schematic diagram of one embodiment of the present invention;

fig. 7(a) is a schematic diagram of a situation where a carrier of a target LTE cell is not overlapped with a dc subcarrier of a target NR cell according to an embodiment of the present invention;

fig. 7(b) is a schematic diagram of a shared spectrum of a carrier of a target LTE cell and a target NR cell, which is provided by the embodiment of the present invention, without including a dc subcarrier;

fig. 8 is a diagram illustrating channel estimation using a set of reference signals according to an embodiment of the present invention;

fig. 9 is a schematic structural diagram of an apparatus for sharing a downlink spectrum according to an embodiment of the present invention;

fig. 10 is a schematic structural diagram of an apparatus for sharing a downlink spectrum according to an embodiment of the present invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the present application more apparent, embodiments of the present invention will be described in further detail below with reference to the accompanying drawings.

To facilitate understanding of the embodiments of the present invention, a system architecture related to the embodiments of the present invention and concepts related to the terms are first described below.

The embodiment of the present invention may be applied to a communication system, as shown in fig. 1, where the communication system includes a base station and a terminal, the terminal is a user equipment that communicates with the base station, and includes a 4G terminal and a 5G terminal, and corresponding to a terminal of a target LTE cell and a terminal of a target NR cell in the embodiment of the present invention, the base station is a dual-system base station, one is LTE, and the other is NR, and frequency spectrums used by LTE and NR are partially overlapped or completely overlapped. The base station comprises at least one LTE cell and at least one NR cell, and the number of the LTE cells is the same as that of the NR cells.

Target LTE cell: any LTE cell included in the base station, for example, the base station includes 5 cells, and the target LTE cell is any one of the LTE cells.

Target NR cell: and the base station is shared with the target LTE cell, and the coverage area of the base station is the same as that of the target LTE cell.

The subcarriers and OFDM symbols of the target NR cell and the target LTE cell meet the following conditions:

the sub-carriers of the target NR cell and the target LTE cell are equally spaced, for example, the sub-carriers are all 15KHZ apart. The length of the OFDM symbols of the subcarriers of the target NR cell and the target LTE cell is equal, for example, the length of each OFDM symbol is one-seventh millisecond.

In addition, the Cyclic Prefix (CP) length of the subcarriers of the target NR cell and the target LTE cell is equal, and the CP is a Prefix added before the OFDM symbol enters the channel and is used to fill the guard interval.

The embodiment of the invention provides a method for sharing a downlink frequency spectrum, and an execution main body of the method is a base station. As shown in fig. 2, the base station may include a receiver 210, a processor 220, and a transmitter 230. The receiver 210 and the transmitter 230 may be respectively connected with the processor 220, the receiver 210 may be used for receiving messages or data, the transmitter 230 may be used for sending messages or data, and the processor 220 may be a control center of the base station, and various interfaces and lines are used for connecting various parts of the whole base station, such as the receiver 210, the transmitter 230, and the like. In this embodiment of the present invention, the processor 220 may be configured to perform processing related to spectrum sharing between an LTE cell and an NR cell, and optionally, the processor 220 may include one or more processing units.

As shown in fig. 3, an embodiment of the present invention provides a method for sharing a downlink spectrum, where a processing flow of the method may include the following steps:

step 301, when the data transmission amount of the target LTE cell is lower than a preset threshold, the base station determines at least one non-MBSFN subframe that is not scheduled of the target LTE cell.

The preset threshold may be set by a technician and stored in the base station, for example, the utilization rate of the time-frequency resource of the target LTE cell is lower than 30%.

In implementation, the base station may continuously detect the data transmission amount of the target LTE cell, and when it is detected that the data transmission amount of the target LTE cell is lower than a preset threshold, at least one non-MBSFN subframe may be determined in non-scheduled non-MBSFN subframes of the target LTE cell, where the non-scheduled non-MBSFN subframe refers to a subframe that is not used for transmitting data to be transmitted by a terminal of the target LTE cell.

In addition, the base station may detect a data transmission amount of the target LTE cell within a period of time, where the period of time may be preset by a technician and stored in the base station, for example, 1 minute, 30 seconds, and the like, and when it is detected that the data transmission amount of the target LTE cell within the period of time is lower than a preset threshold, at least one non-MBSFN subframe may be determined in a non-MBSFN subframe that is not scheduled by the target LTE cell.

In addition, the base station may detect a data transmission amount of the target LTE cell within a period of time and a data transmission amount of the target NR cell within the period of time, and when it is detected that the data transmission amount of the target LTE cell within the period of time is lower than a preset threshold and the data transmission amount of the target NR cell is higher than the preset threshold, the base station may determine at least one non-MBSFN subframe in a non-MBSFN subframe that is not scheduled by the target LTE cell.

Step 302, the base station maps the reference signal of the target LTE cell to the RE of the LTE reference signal in at least one non-MBSFN subframe.

In implementation, after determining at least one non-MBSFN subframe that is not scheduled by the LTE cell, the base station may obtain a pre-stored reference signal of the target LTE cell and a time-frequency position of the LTE reference signal, or generate the reference signal of the target LTE cell by using a preset reference signal generation algorithm, and determine REs of the LTE reference signal in the non-MBSFN subframe by using a PCI of the target LTE cell. And then mapping the reference signal of the target LTE cell to the RE of the LTE reference signal in at least one non-MBSFN subframe.

Optionally, the base station may further map a reference signal of the target NR cell on at least one non-MBSFN subframe, and the corresponding processing may be as follows:

the base station determines a reference signal of a target NR cell, and maps the reference signal of the target NR cell to REs of the NR reference signal in at least one non-MBSFN subframe.

In implementation, the base station may obtain a reference signal of a target NR cell and a time-frequency position of the NR reference signal, which are stored in advance, or generate the reference signal of the target NR cell based on a preset reference signal generation algorithm and determine the time-frequency position of the NR reference signal by using the PCI of the target LTE cell. And then mapping the reference signal of the target NR cell to a time-frequency position RE of the NR reference signal in at least one non-MBSFN subframe, wherein the value of the reference signal of the target NR cell can enable the terminal of the target NR cell to perform channel estimation more accurately. For example, as shown in fig. 4, the "+" sign in the figure indicates a value of the reference signal of the target NR cell.

The scheme of mapping the reference signal of the target NR cell may be applied to a scenario in which the scheduling granularity of the base station corresponding to the target NR cell in the time dimension is not a subframe but may be a smaller time slot. Based on the current discussion progress of 3GPP, the scheduling granularity of the target NR cell in the time dimension, not the subframe but possibly a smaller slot, such as a small slot, contains 4 OFDM symbols, and in the scheduled small slot, a reference signal must be mapped for the terminal of the target NR cell to perform channel estimation. For example, as shown in fig. 4, the value of l in the figure indicates the number of OFDM symbols in one Resource Block (RB), the non-MBSFN subframe of the target LTE cell includes two RBs, the control region is the first two OFDM symbols in the first RB, the mini slot is 4 OFDM symbols, the value of the reference signal of the target NR cell is indicated by an "x" sign, the value of the reference signal of the target LTE cell is indicated by "A, B", data to be transmitted can be transmitted to terminal 1 of the target NR cell through 2 nd (from 0 th) to 5 th OFDM symbols in the first RB, data to be transmitted is transmitted to terminal 2 of the target NR cell through the 6 th OFDM symbol in the first RB to the 2 nd OFDM symbol in the second RB, and sending data to be sent to the terminal 3 of the target NR cell through the 3rd OFDM symbol to the 6 th OFDM symbol in the second RB.

Optionally, when the number of antenna ports of the target LTE cell is less than the number of antenna ports of the target NR cell, the processing of step 302 may be as follows:

the antenna ports of the target LTE cell are a first antenna port and a second antenna port, and the antenna ports of the target NR cell are a first antenna port, a second antenna port, a third antenna port and a fourth antenna port; for the first antenna port and the second antenna port, the base station maps the reference signal of the target LTE cell to the RE of the LTE reference signal in at least one non-MBSFN subframe. For the third antenna port and the fourth antenna port, the base station determines a reference signal of a target NR cell, and maps the reference signal of the target NR cell to REs of the NR reference signal in at least one non-MBSFN subframe.

In implementation, the antenna ports of the target LTE cell correspond to two antenna ports, which are a first antenna port and a second antenna port, and the antenna ports of the target NR cell correspond to four antenna ports, which are a first antenna port, a second antenna port, a third antenna port, and a fourth antenna port. The above-mentioned antenna ports are logical antenna ports, the first antenna port, the second antenna port, the third antenna port, and the fourth antenna port correspond to different physical antennas, and for the first antenna port and the second antenna port, the base station may obtain a reference signal of a target LTE cell and RE of the LTE reference signal, which are stored in advance, or generate the reference signal of the target LTE cell using a generation algorithm of the reference signal, determine RE of the LTE reference signal using PCI of the target LTE cell, and then map the reference signal of the target LTE cell to RE of the LTE reference signal in at least one non-MBSFN subframe.

For the third antenna port and the fourth antenna port, the base station may obtain a reference signal of the target NR cell and REs of the NR reference signal, which are stored in advance, or generate the reference signal of the target NR cell using a generation algorithm of the reference signal, determine REs of the NR reference signal using a PCI of the target NR cell, and then map the reference signal of the target NR cell to REs of the NR reference signal in at least one non-MBSFN subframe. It should be noted here that the reference signal value of the target NR cell and the RE of the NR reference signal determined by the base station enable the terminal of the target NR cell to perform channel estimation.

Step 303, the base station maps the data to be transmitted of the target NR cell to REs in at least one non-MBSFN subframe except for REs of the LTE reference signal.

In implementation, after determining the data to be transmitted of the target NR cell, the base station may perform processing such as scrambling, constellation mapping, layer mapping, and resource mapping on the data to be transmitted, and map the data to be transmitted of the target NR cell to REs other than REs of the LTE reference signal in the non-MBSFN subframe.

Optionally, the base station maps the data to be transmitted of the target NR cell to REs except for REs of the LTE reference signal in the data region of the at least one non-MBSFN subframe.

In implementation, the non-MBSFN subframe of the target LTE cell may be divided into a data region and a control region, where the data region may be used for transmitting reference signals and data, and the control region may be used for transmitting reference signals and control information. Although at least one non-MBSFN subframe determined by the base station is a subframe that is not called by the target LTE cell, a control region on the non-MBSFN subframe is also a reference signal to be transmitted to the target LTE cell, and is used for a terminal of the target LTE cell to perform channel estimation, radio resource measurement, and the like, and sometimes control information is also transmitted, so as not to affect the transmission of the control information by the target LTE cell, when the non-MBSFN subframe of the target LTE cell is shared by the base station to the target NR cell, the control region of the target LTE cell is not occupied by the control region by the control target NR cell, so that the base station can perform processing such as scrambling, constellation mapping, layer mapping, resource mapping, and the like on data to be transmitted of the target NR cell, and map the data to be transmitted of the target NR cell to REs other than REs of the LTE reference signal in the data region of the at least one non-MBSFN subframe.

In addition, the target NR cell may also use a control region in at least one non-MBSFN subframe, for example, the target LTE cell does not need to transmit control information, and the base station may map data to be transmitted of the target NR cell to REs in the control region in at least one subframe, except for REs of the LTE reference signal. In this way, the target NR cell can use more REs.

In addition, if the target LTE cell does not need to transmit the control channel, the target NR cell may use more REs, and may use the control region and the data region of the non-MBSFN subframe.

Optionally, when the reference signal of the target NR cell is transmitted through at least one non-MBSFN subframe, the processing in step 303 may be as follows:

and the base station maps the data to be transmitted of the target NR cell to the REs except for the REs of the LTE reference signal and the NR reference signal in at least one non-MBSFN subframe.

In implementation, after determining the data to be transmitted of the target NR cell, the base station may perform processing such as scrambling, constellation mapping, layer mapping, and resource mapping on the data to be transmitted, and map the data to be transmitted of the target NR cell to REs except REs of the LTE reference signal and the NR reference signal in the non-MBSFN subframe.

Optionally, corresponding to the processing procedure in step 302 when the number of antenna ports of the target LTE cell is less than the number of antenna ports of the target NR cell, the processing in step 303 may be as follows:

for the first antenna port and the second antenna port, the base station maps the data to be sent of the target NR cell to the REs except for the RE of the LTE reference signal in at least one non-MBSFN subframe, and for the third antenna port and the fourth antenna port, the base station maps the data to be sent of the target NR cell to the REs except for the RE of the NR reference signal in at least one non-MBSFN subframe.

In implementation, for the first antenna port and the second antenna port, after determining the data to be transmitted of the target NR cell, the base station may perform processing such as scrambling, constellation mapping, layer mapping, and resource mapping on the data to be transmitted, and map the data to be transmitted of the target NR cell to REs except for REs of the LTE reference signal in the non-MBSFN subframe. For the third antenna port and the fourth antenna port, after determining the data to be transmitted of the target NR cell, the base station may perform processing such as scrambling, constellation mapping, layer mapping, and resource mapping on the data to be transmitted of the target NR cell, and map the data to be transmitted of the target NR cell to REs other than REs of the NR reference signal in the non-MBSFN subframe.

Step 304, the base station sends the reference signal and the data to be sent through at least one non-MBSFN subframe.

In implementation, the base station may send the reference signal and the data to be sent through at least one non-MBSFN subframe, and the terminal of the target LTE cell may obtain the reference signal from the RE of the LTE reference signal in the non-MBSFN subframe, to perform channel estimation, radio resource measurement, and the like. The terminal of the target NR cell may obtain the reference signal of the target LTE cell as its own reference signal from the REs of the LTE reference signal in the non-MBSFN subframe, perform channel estimation, determine a channel matrix H, map the REs of the data to be sent from the non-MBSFN subframe, obtain the data to be sent, and determine the data to be sent by the base station using the channel matrix H. In this way, the terminal of the target LTE cell can perform radio resource measurement and channel estimation without affecting the use of the terminal of the target LTE cell, and the target NR cell can also use non-MBSFN subframes that are not scheduled by the target LTE cell.

Alternatively, a transmit diversity transmit mode may be used to transmit the reference signal and the data to be transmitted, and the corresponding processing in step 304 may be as follows:

and the base station transmits the reference signal and the data to be transmitted through at least one non-MBSFN subframe by using a transmission mode of the transmission diversity.

In implementation, if the base station transmits data to the terminal of the target NR cell, precoding processing is used, the reference signal of the target LTE cell is inserted before precoding processing, and after precoding processing, the reference signal of the target LTE cell changes because the value of the reference signal of the target LTE cell is multiplied by a precoding matrix. Therefore, if the target NR cell wants to share the non-MBSFN subframe that is not scheduled by the target LTE cell, the reference signal of the target LTE cell cannot be precoded. On different RBs on one subframe, the target NR cell may adopt different precoding matrices (for example, precoding matrices of terminals directed to different target NR cells are different), and thus, different precoding matrices are used for reference signals on different RBs of the target LTE cell, which results in that the terminal of the target LTE cell cannot correctly receive the reference signals. Here, a transmission mode of the transmit diversity is generally used, where the transmission mode of the transmit diversity refers to sending the same reference signal and data to be sent at different antenna ports, and even if a terminal of a target NR cell does not receive the reference signal and the data to be sent at a first antenna port, the terminal can also receive the reference signal and the data to be sent at a second antenna port, so that a success rate of data transmission can be improved.

It should be noted here that, if the target NR cell shares the MBSFN subframe of the target LTE cell, the target NR cell of the base station may use precoding processing, so that the data to be transmitted sent by different antenna ports are different, and the amount of data to be transmitted is large, thereby improving the efficiency of data transmission.

In the embodiment of the present invention, a scheme for performing linear transformation on an LTE reference signal is further provided, and corresponding processing may be as follows:

the base station performs linear transformation on the reference signal of the target LTE cell based on a preset linear general formula, wherein the preset linear general formula is a unitary matrix, and the modulus of elements is equal.

In implementation, the preset linear general formula is set by a technician and stored in the base station, the preset linear general formula is a unitary matrix, and the modulus of each element in the matrix is equal. When a preset linear general formula is set, the linear general formula meets the following two conditions, firstly, the sum of the transmitting power of all antenna ports participating in linear transformation before and after the linear transformation is the same, and in addition, if the transmitting power of two or more antenna ports before the linear transformation is equal, the transmitting power of two or more antenna ports after the linear transformation is also equal, so that the total transmitting power of a base station is not changed, the condition that the coverage area of the base station is enlarged or reduced is avoided, the terminal covered by the base station cannot receive a reduced reference signal or data, the terminal covered by other base stations cannot receive the reference signal or data sent by the base station, and the radio frequency specification of the antenna ports does not need to be changed; secondly, the transmitting power of the RE corresponding to the LTE reference signal of all the antenna ports after the linear transformation is the same, so that the terminal of the target NR cell and the terminal of the target LTE cell are notified conveniently to obtain the reference signal, and the accuracy of channel estimation performed by the terminal of the target NR cell is also improved.

Taking an example that the antenna port of the target LTE cell and the antenna port of the target NR cell are both the first antenna port and the second antenna port, the preset linear general formula that satisfies the above two conditions may be:

where α, β, and Δ are preset real numbers, and j is an imaginary unit, for example, when Δ ═ α ═ β ═ 0,

when alpha is 0,

When the temperature of the water is higher than the set temperature,

when α ═ β ═ 0 and Δ ═ pi, then,

and the like.

After the base station maps the reference signal of the target LTE cell to the RE of the LTE reference signal in at least one non-MBSFN subframe, the base station can perform linear transformation on the reference signal of the target LTE cell mapped to the RE of the LTE reference signal by using a preset linear general formula, and then the target LTE cell is used as the targetThe antenna port of the LTE cell and the antenna port of the target NR cell are both a first antenna port and a second antenna port, which are taken as examples, and values of reference signals mapped on the kth subcarrier and the RE corresponding to the l-th OFDM symbol in the non-MBSFN subframe sent by the first antenna port are taken before and after linear transformation to obtain values

And

indicating that values of reference signals mapped on the k subcarrier in the non-MBSFN subframe sent by the second antenna port and the RE corresponding to the l OFDM symbol before and after linear transformation

And

expressed, the preset linear transformation general formula is expressed by P, and the linear transformation formula is

For example,

and

can be expressed as:

after the linear transformation, the reference signal sent by the base station through at least one non-MBSFN subframe is the reference signal after the linear transformation.

For example, as shown in fig. 5, the reference signal of the target LTE cell on the non-MBSFN subframe transmitted through the first antenna port takes a value of R₁、R₂……R₈The reference signal of the target LTE cell on the RE at the same time-frequency position on the MBSFN subframe sent through the second antenna port takes a value of 0, the reference signal of the target LTE cell on the non-MBSFN subframe sent through the first antenna port takes a value of 0, and the reference signal of the target LTE cell on the RE at the same time-frequency position on the MBSFN subframe sent through the second antenna port takes a value of R₉、R₁₀……R₁₆The preset linear formula is

The values of the reference signal after the linear transformation are shown in figure 5,

as can be seen from fig. 5, since the values of the reference signals of the target LTE cell after the linear transformation of the REs at the same time-frequency position of the non-MBSFN subframe sent by the two antenna ports are equal or opposite, the transmission powers of the REs of the LTE reference signals corresponding to the first antenna port and the second antenna port after the linear transformation are the same.

It should be noted that the linear transformation is performed only for the antenna port transmitting the Reference Signal, and the linear transformation is not required for the antenna port not transmitting the Reference Signal, where the antenna port transmitting the Reference Signal may be understood as an antenna port transmitting the CRS of the target LTE cell, and where the Reference Signal is the CRS and is understood as an antenna port transmitting the Channel State Information Reference Signal (CSI-RS) of the target LTE cell.

Or, the linear transformation may be that the base station performs linear transformation on the reference signal of the target LTE cell in advance, stores the value of the reference signal after the linear transformation, and maps the reference signal after the linear transformation to the RE of the LTE reference signal when the base station transmits the data to be transmitted of the target NR cell through the non-MBSFN subframe that is not scheduled.

In addition, the embodiment of the present invention further provides a scheme for performing linear transformation on a reference signal of a target LTE cell when the number of antenna ports of the target LTE cell is 4 and the number of antenna ports of the target NR cell is 4 or greater than 4, and the corresponding processing may be as follows:

the number of antenna ports of the target LTE cell is 4, the number of antenna ports of the target NR cell is 4 or more, the linear general formula is unitary matrix, and the modulus of each element in the matrix is equal, and only one specific example of the linear general formula is given here, such as

And the like.

Optionally, in the embodiment of the present invention, a scheme is further provided that does not affect data transmission of a non-MBSFN subframe that is not used by a target NR cell, and corresponding processing may be as follows:

the base station carries out linear transformation on the data to be sent and the reference signal mapped in the non-MBSFN subframe of the target LTE cell based on a preset linear general formula.

In implementation, after the base station performs scrambling, constellation mapping, layer mapping, precoding, resource mapping and other processing on the reference signal and the data to be transmitted of the target LTE cell, the reference signal and the data to be transmitted of the target LTE cell are mapped to other subframes except for at least one non-MBSFN subframe, and the base station may obtain a preset linear general formula and then perform linear transformation on the reference signal and the data to be transmitted based on the preset linear general formula. The processing of the linear transformation is the same as that of the linear transformation described above and will not be described herein again. If at least one non-MBSFN subframe has data to be sent of a target LTE cell, the data to be sent of the target LTE cell also needs to be linearly transformed based on a preset linear general formula.

Assuming that a channel matrix from a base station to a UE is marked as H, H is a matrix of 2 x 2, and linear transformation is carried out on a reference signal and data to be transmitted on the basis of a preset linear general formulaIn other words, the vector of the signal received by the terminal is denoted by r, where r is Hx, where x is the reference signal transmitted by the base station,

to represent

The transposing of (1). After linear transformation is performed based on a preset linear general formula, a vector of a signal received by a terminal is represented by r, and r is HPx and H₁x, wherein P represents a predetermined linear formula, H₁HP, so that the P matrix is unitary, H and H₁The channel matrix has the same statistical characteristics and is an equivalent channel, and the channel matrixes have the same autocorrelation function and the same channel fading, so that the data received by the terminal of the target LTE cell is not influenced by the linear transformation.

And for the data to be sent of the target NR cell, linear transformation is not needed, and the terminal of the target NR cell calculates a channel matrix H according to the reference signal acquired from the non-MBSFN subframe₁I.e. the channel matrix of the data to be sent in the target NR cell.

In addition, it should be noted that, when the terminal of the target LTE cell is configured with a Transmission Mode 9(Transmission Mode Nine, TM9) and a Precoding Matrix Indicator (PMI)/Rank Indicator (RI) report, a Channel Quality Indicator (CQI) reported by the terminal of the target LTE cell is obtained based on measurement of the CSI-RS, and antenna ports used by the base station to send the CSI-RS and a reference signal of the target LTE cell are different, and linear transformation processing is not performed on the CSI-RS, so the CQI obtained by the base station is the Channel Quality of an actual Channel. For the case that the terminal of the target LTE cell is configured with TM9 but is not configured with PMI/RI reporting, the CQI reported by the terminal of the target LTE cell is obtained based on the measurement of the reference signal of the target LTE cell, and if the base station performs linear transformation on the reference signal of the target LTE cell, the CQI measured by the terminal reflects the channel quality of the equivalent channel. Generally, for the situation that a terminal of a target LTE cell is configured with TM9 but is not configured with PMI/RI for reporting, a base station knows CQI of an equivalent channel in a Time Division Duplex (TDD) mode, and then can obtain channel quality of an actual channel through reciprocity between an uplink channel and a downlink channel. In this way, the base station does not affect the use of the terminal of the target LTE cell after linearly changing the reference signal of the target LTE cell.

In addition, the embodiment of the present invention further provides a scheme that linear transformation is not performed on to-be-transmitted data and reference signals mapped in non-MBSFN subframes of a target LTE cell, and linear transformation is performed on to-be-transmitted data and reference signals mapped on all subframes used by a target NR cell, where corresponding processing may be as follows:

the base station may obtain a reference signal of a target NR cell and REs of the NR reference signal stored in advance, or generate the reference signal of the target NR cell using a preset reference signal generation algorithm, and determine the REs of the NR reference signal in the non-MBSFN subframe using a PCI of the target NR cell. Then, the reference signal of the target NR cell is mapped to the RE of the NR reference signal of at least one non-MBSFN subframe, and the data to be transmitted of the target NR cell is mapped to the RE except the RE of the NR reference signal. And then carrying out linear transformation on the data to be transmitted and the reference signal of the target NR cell based on a preset linear general formula Q, wherein the preset linear general formula Q is the transposed conjugate of the aforementioned linear general formula P, the value of the reference signal of the target NR cell is the value of the reference signal of the target LTE cell after the linear transformation, and then transmitting the reference signal of the NR cell and the data to be transmitted after the linear transformation through at least one non-MBSFN subframe. In this way, the reference signal acquired by the terminal of the target LTE cell is the reference signal that should be actually received, and the reference signal acquired by the terminal of the target NR cell is the reference signal of the NR cell after linear transformation, so that the data to be transmitted in the NR cell is also linearly transformed, and the data to be transmitted can be correctly analyzed.

In the embodiment of the present invention, a method for reducing overhead of control information indicating a time-frequency position of a reference signal of a target NR cell is further provided, and corresponding processing may be as follows:

in at least one non-MBSFN subframe, the center frequency of subcarriers corresponding to all REs to which data to be sent of any terminal in a target NR cell is mapped is greater than or less than the center frequency of a direct current DC subcarrier of a target LTE cell.

In implementation, as shown in fig. 6, the DC subcarrier of the target LTE cell overlaps with the DC subcarrier of the target NR cell, the DC subcarrier is not included in the non-MBSFN subframe of the target LTE cell, and the DC subcarrier may be included in the non-MBSFN subframe of the target NR cell. Thus, since the DC subcarrier cannot be used for mapping the reference signal and the data to be transmitted, after the reference signal of the target LTE cell crosses over one DC subcarrier, the interval of the reference signal of the target LTE cell in the frequency dimension becomes larger, for example, if 3 subcarriers of the interval of the reference signal of the original target LTE cell are crossed over the DC subcarrier, the interval becomes 4 subcarriers. However, the reference signals of the target NR cell are generally distributed at equal intervals in the frequency dimension, such as 3 subcarriers, so that when the target NR cell shares the reference signal of the target LTE cell, all REs mapped by the data to be transmitted of any terminal corresponding to the target NR cell generally do not span the DC subcarrier, that is, the center frequencies of all subcarriers mapped by the data to be transmitted of any terminal corresponding to the target NR cell are all greater than or all less than the center frequency of the DC subcarrier of the target LTE cell. Therefore, the terminal of the target NR cell can acquire the reference signal from the non-MBSFN subframe at equal intervals without sending the indication control information of the change of the interval of the reference signal, thereby saving downlink transmission resources.

In the embodiment of the present invention, a method for defining a time-frequency position of a reference signal of a target LTE cell when frequency spectrums occupied by the target NR cell and the target LTE cell are partially overlapped is also provided, and corresponding processing may be as follows:

the DC subcarrier of the target LTE cell is not overlapped with the DC subcarrier of the target NR cell; the center frequency of the subcarrier corresponding to the reference signal of the target LTE cell is not equal to the center frequency of the DC subcarrier of the target NR cell.

In implementation, the DC subcarrier is a subcarrier set at a carrier center position and cannot be used for transmitting data, so that the base station cannot map the reference signal onto the DC subcarrier of the target NR cell or the target LTE cell when the target NR cell or the target LTE cell transmits data through a non-MBSFN subframe. When the frequency spectrums occupied by the target NR cell and the target LTE cell are partially overlapped, as shown in fig. 7(a), one case is that when the frequency spectrums are partially overlapped, the DC subcarrier of the target LTE cell and the DC subcarrier of the target NR cell are not overlapped, when the base station is established, the PCI of the target LTE cell is set, so that the reference signal of the target LTE cell cannot be mapped onto the DC subcarrier of the target NR cell, that is, the center frequency of the subcarrier corresponding to the reference signal of the target LTE cell is not equal to the center frequency of the DC subcarrier of the target NR cell. It should be noted here that the time-frequency position of the reference signal of the target LTE cell is calculated according to the PCI of the target LTE cell. As shown in fig. 7(b), in another case, when the frequency spectrums are partially overlapped, the DC subcarrier of the target NR cell is not included in the overlapped partial frequency spectrums, and in this case, the setting of the PCI of the target LTE cell does not need to be considered.

In the embodiment of the present invention, a scheme for optimizing channel estimation when a base station continuously schedules a plurality of non-MBSFN subframes for a terminal of a target NR cell is further provided, and corresponding processing may be as follows:

the base station continuously schedules a plurality of non-MBSFN subframes for the terminal of the target NR cell, and when the terminal of the target NR cell carries out channel estimation, the channel is supposed to be kept unchanged within the length of a preset number of OFDM symbols, as shown in fig. 8, two non-MBSFN subframes are consecutively scheduled, consecutive 4 OFDM symbols are grouped, the first dotted circle encloses 4 OFDM symbols, there is a reference signal on the RE of the first and fourth OFDM symbols in the virtual circle, the reference signals on the REs of the first OFDM symbol and the fourth OFDM symbol may be used, the reference signals of the first OFDM symbol and the fourth OFDM symbol may be determined, then, channel estimation is performed, for example, values of reference signals on REs of a first OFDM symbol and a fourth OFDM symbol in a group of OFDM symbols may be averaged, and the averaged value is used as a reference signal of a channel in which the second OFDM symbol and the third OFDM symbol are respectively located.

In addition, special processing may be performed on the first and last appearing reference signals, for example, in fig. 8, the first appearing reference signal and the adjacent reference signal may be combined into a group of reference signals for channel estimation.

Here, A, B in fig. 8 indicates the value of the reference signal.

It should be noted that the non-MBSFN subframe mentioned in the embodiment of the present invention is a subframe of the target LTE cell.

Fig. 9 is a structural diagram of an apparatus for sharing a downlink spectrum according to an embodiment of the present invention. The apparatus may be implemented as part or all of an apparatus in software, hardware, or a combination of both. The apparatus for sharing a downlink spectrum according to the embodiment of the present invention may implement the process described in fig. 3 according to the embodiment of the present invention, and the apparatus includes: a determining module 910, a mapping module 920, and a sending module 930, wherein:

the determining module 910 is configured to determine at least one non-multimedia broadcast multicast single frequency network MBSFN subframe that is not scheduled in a target Long Term Evolution (LTE) cell when a data transmission amount of the target LTE cell is lower than a preset threshold;

the mapping module 920 is configured to map the reference signal of the target LTE cell to the resource element RE of the LTE reference signal in the at least one non-MBSFN subframe;

the mapping module 920 is configured to map data to be sent of a target new wireless NR cell to REs in the at least one non-MBSFN subframe except for REs of the LTE reference signal;

the sending module 930 is configured to send the reference signal and the data to be sent through the at least one non-MBSFN subframe.

Optionally, the mapping module 920 is configured to:

mapping data to be transmitted of the target NR cell to REs of the LTE reference signal in a data region of the at least one non-MBSFN subframe.

Optionally, as shown in fig. 10, the apparatus further includes:

a transformation module 940, configured to perform linear transformation on the reference signal of the target LTE cell based on a preset linear general formula, where the preset linear general formula is a unitary matrix and the moduli of elements are equal.

Optionally, the transformation module 940 is configured to:

and performing linear transformation on the data to be sent and the reference signal mapped in the non-MBSFN subframe of the target LTE cell based on the preset linear general formula.

Optionally, the mapping module 920 is further configured to:

determining a reference signal of the target NR cell, and mapping the reference signal of the target NR cell to REs of the NR reference signal in the at least one non-MBSFN subframe;

the mapping module 920 is configured to:

mapping data to be transmitted of the target NR cell to REs of the at least one non-MBSFN subframe except for REs of the LTE reference signal and the NR reference signal.

Optionally, the intervals of the subcarriers of the target NR cell and the target LTE cell are the same, and the lengths of the orthogonal frequency division multiplexing OFDM symbols are the same.

Optionally, the sending module 930 is configured to:

and transmitting the reference signal and the data to be transmitted through the at least one non-MBSFN subframe by using a transmission mode of transmission diversity.

Optionally, in the at least one non-MBSFN subframe, a center frequency of a subcarrier corresponding to all REs to which data to be sent of any terminal in the target NR cell is mapped is greater than or less than a center frequency of a direct current DC subcarrier of the target LTE cell.

Optionally, the DC subcarrier of the target LTE cell does not overlap with the DC subcarrier of the target NR cell; the center frequency of a subcarrier corresponding to the reference signal of the target LTE cell is not equal to the center frequency of the DC subcarrier of the target NR cell.

Optionally, the antenna ports of the target LTE cell are a first antenna port and a second antenna port, and the antenna ports of the target NR cell are the first antenna port, the second antenna port, the third antenna port, and a fourth antenna port;

the mapping module 920 is configured to:

for the first antenna port and the second antenna port, mapping the reference signal of the target LTE cell to the REs of the LTE reference signal in the at least one non-MBSFN subframe;

the mapping module 920 is further configured to:

for the third antenna port and the fourth antenna port, determining a reference signal of the target NR cell, mapping the reference signal of the target NR cell to REs of NR reference signals in the at least one non-MBSFN subframe;

the mapping module 920 is configured to map, for the first antenna port and the second antenna port, to-be-transmitted data of a target new wireless NR cell to REs except for REs of the LTE reference signal in the at least one non-MBSFN subframe, and map, for the third antenna port and the fourth antenna port, to-be-transmitted data of the target NR cell to REs except for REs of the NR reference signal in the at least one non-MBSFN subframe.

It should be noted that the determining module 910, the mapping module 920 and the sending module 930 may be implemented by the processor 220, or the processor 220 may be implemented in cooperation with the transmitter 230.

In the above embodiments, all or part of the implementation may be realized by software, hardware, firmware or any combination thereof, and when the implementation is realized by software, all or part of the implementation may be realized in the form of a computer program product. The computer program product comprises one or more computer program instructions which, when loaded and executed on a base station, cause the flow or functions according to embodiments of the invention to be performed, in whole or in part. The computer instructions may be stored in a computer readable storage medium or transmitted from one computer readable storage medium to another, for example, the computer instructions may be transmitted from one website, computer, server, or data center to another website, computer, server, or data center by wire (e.g., coaxial cable, fiber optics, digital subscriber line) or wirelessly (e.g., infrared, wireless, microwave, etc.). The computer readable storage medium can be any available medium that can be accessed by the base station or a data storage device, such as a server, data center, etc., that can comprise an integration of one or more available media. The usable medium may be a magnetic medium (such as a floppy Disk, a hard Disk, a magnetic tape, etc.), an optical medium (such as a Digital Video Disk (DVD), etc.), or a semiconductor medium (such as a solid state Disk, etc.).

The above description is only one embodiment of the present application and should not be taken as limiting the present application, and any modifications, equivalents, improvements, etc. made within the spirit and principle of the present application should be included in the protection scope of the present application.

Claims

1. A method for sharing a downlink spectrum, the method comprising:

when the data transmission quantity of a target Long Term Evolution (LTE) cell is lower than a preset threshold value, a base station determines at least one non-scheduled non-multimedia broadcast multicast single frequency network (MBSFN) subframe of the target LTE cell;

the base station maps the reference signal of the target LTE cell to the resource unit RE of the LTE reference signal in the at least one non-MBSFN subframe;

the base station maps data to be sent of a target new wireless NR cell to REs except for REs of the LTE reference signal in the at least one non-MBSFN subframe, wherein in the at least one non-MBSFN subframe, the center frequency of subcarriers corresponding to all the REs to which the data to be sent of any terminal in the target NR cell is mapped is greater than or less than the center frequency of a Direct Current (DC) subcarrier of the target LTE cell;

and the base station transmits the reference signal and the data to be transmitted through the at least one non-MBSFN subframe.

2. The method of claim 1, wherein the base station maps data to be sent of a target new wireless NR cell to REs of the at least one non-MBSFN subframe other than REs of the LTE reference signal, comprising:

and the base station maps the data to be sent of the target NR cell to the REs of the LTE reference signal in the data area of the at least one non-MBSFN subframe.

3. The method of claim 1, further comprising:

and the base station performs linear transformation on the reference signal of the target LTE cell based on a preset linear general formula, wherein the preset linear general formula is a unitary matrix, and the modulus of elements is equal.

4. The method of claim 3, further comprising:

and the base station carries out linear transformation on the data to be sent and the reference signal mapped in the non-MBSFN subframe of the target LTE cell based on the preset linear general formula.

5. The method of claim 1, wherein the base station maps the reference signal of the target LTE cell to the Resource Elements (REs) of the LTE reference signal in the at least one non-MBSFN subframe, and further comprising:

the base station determines a reference signal of the target NR cell, and maps the reference signal of the target NR cell to REs of the NR reference signal in the at least one non-MBSFN subframe;

the base station maps data to be sent of a target new wireless NR cell to REs of the at least one non-MBSFN subframe except for REs of the LTE reference signal, and the method comprises the following steps:

and the base station maps the data to be sent of the target NR cell to the REs of the at least one non-MBSFN subframe except the REs of the LTE reference signal and the NR reference signal.

6. The method of claim 1, wherein the target NR cell and the target LTE cell have the same subcarrier spacing and the same length of orthogonal frequency division multiplexing, OFDM, symbol.

7. The method of claim 1, wherein the base station transmits the reference signal and the data to be transmitted through the at least one non-MBSFN subframe, and wherein the transmitting comprises:

and the base station transmits the reference signal and the data to be transmitted through the at least one non-MBSFN subframe by using a transmission mode of transmission diversity.

8. The method of claim 1, wherein a DC subcarrier of the target LTE cell does not overlap with a DC subcarrier of the target NR cell; the center frequency of a subcarrier corresponding to the reference signal of the target LTE cell is not equal to the center frequency of the DC subcarrier of the target NR cell.

9. The method of claim 1, wherein the antenna ports of the target LTE cell are a first antenna port and a second antenna port, and wherein the antenna ports of the target NR cell are the first antenna port, the second antenna port, a third antenna port, and a fourth antenna port;

the base station maps the reference signal of the target LTE cell to the resource element RE of the LTE reference signal in the at least one non-MBSFN subframe, and the method comprises the following steps:

for the first antenna port and the second antenna port, the base station maps the reference signal of the target LTE cell to the REs of the LTE reference signal in the at least one non-MBSFN subframe;

the method further comprises the following steps:

for the third antenna port and the fourth antenna port, the base station determining a reference signal of the target NR cell, mapping the reference signal of the target NR cell to REs of NR reference signals in the at least one non-MBSFN subframe;

the base station maps data to be transmitted of a target NR cell to REs of the at least one non-MBSFN subframe except for REs of the LTE reference signal, and the method comprises the following steps:

for the first antenna port and the second antenna port, the base station maps data to be transmitted of the target NR cell to REs except REs of the LTE reference signal in the at least one non-MBSFN subframe, and for the third antenna port and the fourth antenna port, the base station maps data to be transmitted of the target NR cell to REs except REs of the NR reference signal in the at least one non-MBSFN subframe.

10. A base station, comprising a transmitter and a processor, wherein:

the processor is used for determining at least one non-scheduled non-multimedia broadcast multicast single frequency network (MBSFN) subframe of a target Long Term Evolution (LTE) cell when the data transmission quantity of the target LTE cell is lower than a preset threshold value;

the processor is configured to map the reference signal of the target LTE cell to Resource Elements (REs) of an LTE reference signal in the at least one non-MBSFN subframe;

the processor is configured to map data to be sent of a target new wireless NR cell to REs other than REs of the LTE reference signal in the at least one non-MBSFN subframe, where in the at least one non-MBSFN subframe, a center frequency of a subcarrier corresponding to all REs to which data to be sent of any terminal in the target NR cell is mapped is greater than or less than a center frequency of a DC subcarrier of the target LTE cell;

the transmitter is configured to transmit the reference signal and the data to be transmitted through the at least one non-MBSFN subframe.

11. The base station of claim 10, wherein the processor is configured to:

12. The base station of claim 10, wherein the processor is further configured to:

and performing linear transformation on the reference signal of the target LTE cell based on a preset linear general formula, wherein the preset linear general formula is a unitary matrix, and the modulus of elements is equal.

13. The base station of claim 12, wherein the processor is further configured to:

14. The base station of claim 10, wherein the processor is further configured to:

the processor is configured to:

15. The base station of claim 10, wherein the target NR cell and the target LTE cell have the same subcarrier spacing and the same length of orthogonal frequency division multiplexing, OFDM, symbol.

16. The base station of claim 10, wherein the transmitter is configured to transmit the uplink packet to the base station

17. The base station of claim 10, wherein the DC subcarrier of the target LTE cell does not overlap with the DC subcarrier of the target NR cell; the center frequency of a subcarrier corresponding to the reference signal of the target LTE cell is not equal to the center frequency of the DC subcarrier of the target NR cell.

18. The base station of claim 10, wherein the antenna ports of the target LTE cell are a first antenna port and a second antenna port, and wherein the antenna ports of the target NR cell are the first antenna port, the second antenna port, a third antenna port, and a fourth antenna port;

the processor is configured to:

the processor is further configured to:

the processor is configured to map, for the first antenna port and the second antenna port, to-be-transmitted data of the target NR cell to REs except for REs of the LTE reference signal in the at least one non-MBSFN subframe, and map, for the third antenna port and the fourth antenna port, to-be-transmitted data of the target NR cell to REs except for REs of the NR reference signal in the at least one non-MBSFN subframe.

19. An apparatus for sharing downlink spectrum, the apparatus comprising:

the device comprises a determining module, a judging module and a judging module, wherein the determining module is used for determining at least one non-multimedia broadcast multicast single frequency network (MBSFN) subframe which is not scheduled in a target Long Term Evolution (LTE) cell when the data transmission quantity of the target LTE cell is lower than a preset threshold;

a mapping module, configured to map the reference signal of the target LTE cell to Resource Elements (REs) of an LTE reference signal in the at least one non-MBSFN subframe;

the mapping module is configured to map data to be sent of a target new wireless NR cell to REs, excluding REs of the LTE reference signal, in the at least one non-MBSFN subframe, where a center frequency of a subcarrier corresponding to all REs to which data to be sent of any terminal in the target NR cell is mapped is greater than or less than a center frequency of a DC subcarrier of the target LTE cell;

a sending module, configured to send the reference signal and the data to be sent through the at least one non-MBSFN subframe.

20. The apparatus of claim 19, wherein the mapping module is configured to:

21. The apparatus of claim 19, further comprising:

and the transformation module is used for carrying out linear transformation on the reference signal of the target LTE cell based on a preset linear general formula, wherein the preset linear general formula is a unitary matrix, and the modulus of elements is equal.

22. The apparatus of claim 21, wherein the transformation module is configured to:

23. The apparatus of claim 19, wherein the mapping module is further configured to:

the mapping module is configured to:

24. The apparatus of claim 19, wherein the target NR cell and the target LTE cell have the same subcarrier spacing and the same length of orthogonal frequency division multiplexing, OFDM, symbol.

25. The apparatus of claim 19, wherein the sending module is configured to:

26. The apparatus of claim 19, wherein a DC subcarrier of the target LTE cell does not overlap with a DC subcarrier of the target NR cell; the center frequency of a subcarrier corresponding to the reference signal of the target LTE cell is not equal to the center frequency of the DC subcarrier of the target NR cell.

27. The apparatus of claim 19, wherein the antenna ports of the target LTE cell are a first antenna port and a second antenna port, and wherein the antenna ports of the target NR cell are the first antenna port, the second antenna port, a third antenna port, and a fourth antenna port;

the mapping module is configured to:

the mapping module is further configured to:

the mapping module is configured to map, for the first antenna port and the second antenna port, to-be-transmitted data of a target NR cell to REs except for REs of the LTE reference signal in the at least one non-MBSFN subframe, and map, for the third antenna port and the fourth antenna port, to-be-transmitted data of the target NR cell to REs except for REs of the NR reference signal in the at least one non-MBSFN subframe.

28. A computer-readable storage medium storing instructions that, when executed on a base station, cause the base station to perform the method of any of claims 1-9.