CN106656892B

CN106656892B - Method and device for transmitting data

Info

Publication number: CN106656892B
Application number: CN201510724560.6A
Authority: CN
Inventors: 屈代明; 刘霞东; 江涛; 陈磊
Original assignee: Huawei Technologies Co Ltd
Current assignee: XFusion Digital Technologies Co Ltd
Priority date: 2015-10-30
Filing date: 2015-10-30
Publication date: 2020-04-24
Anticipated expiration: 2035-10-30
Also published as: CN106656892A; WO2017071574A1

Abstract

According to the method and the device for sending data, the data rate of each sub-band signal is unified by respectively carrying out frequency domain filtering and frequency domain mapping on each sub-band signal and then carrying out inverse Fourier transform, so that the filtering of each sub-band signal can be carried out at a lower sampling rate, and compared with time domain filtering in the related technology and filtering of each sub-band which needs to be operated at a higher sampling rate, the complexity of an F-OFDM transmitter is effectively reduced.

Description

Method and device for transmitting data

Technical Field

The present invention relates to communications technologies, and in particular, to a method and a device for transmitting data.

Background

Orthogonal Frequency Division Multiplexing (OFDM) is a widely used multi-carrier modulation technique. The main idea of the OFDM technique is: the channel is divided into a plurality of orthogonal sub-channels, the high-speed data signal is converted into parallel low-speed sub-data streams, and the parallel low-speed sub-data streams are modulated to each sub-channel for transmission. The OFDM technology is widely used mainly because it has the following advantages: the high frequency spectrum utilization rate can effectively resist frequency selective fading channels, and by introducing Cyclic Prefix (CP), Inter Symbol Interference (ISI) can be eliminated, and meanwhile, a receiver can adopt a simpler single tap equalization algorithm.

However, compared to a single carrier system, the OFDM system also has some problems to be solved. One of the disadvantages of the OFDM system is that it requires strict frequency synchronization and good time synchronization between different subbands. This requires that the sub-carrier spacing, symbol length, and CP length of OFDM should be consistent in the whole system bandwidth, otherwise it is difficult to achieve time and frequency synchronization on different sub-bands.

The OFDM based on subband filtering (F-OFDM for short) is used as a new multi-carrier modulation technology, can use parameters such as different subcarrier intervals, symbol lengths, CP lengths and the like in different subbands, and provides a method for solving intersymbol interference brought by a filter. Fig. 1 is a schematic structural diagram of an F-OFDM transmitter in the related art, and as shown in fig. 1, a system bandwidth is divided into N sub-bands, each sub-band performs sub-carrier mapping, Inverse Fast Fourier Transform (IFFT), CP addition, and filtering independently, and finally performs combining transmission. For each sub-band, the sub-carrier spacing, the symbol length, and the CP length of each sub-band can be adaptively adjusted to adapt to channel scenarios and service types of different User Equipments (UEs).

Since the signals of the individual subbands are finally directly combined together, their sampling rates need to be the same, which means that a high sampling rate filter is required although the bandwidth of each subband may not be large. For example, assuming that the total system bandwidth is 80MHz and divided into 4 20MHz sub-bands with sub-carrier spacing of 15kHz, and assuming an output sampling rate of 30.72MHz, all 4 sub-bands need to use 2048-point IFFT, and each sub-band needs to operate at a sampling rate of 30.72MHz, which increases complexity as a whole.

Disclosure of Invention

The method and the device for sending data provided by the embodiment of the invention can effectively reduce the complexity of the F-OFDM transmitter.

In a first aspect, a method for transmitting data is provided, including:

generating at least two subband signals, wherein the at least two subband signals comprise data to be transmitted;

respectively carrying out frequency domain filtering on the at least two sub-band signals to obtain frequency domain signals corresponding to the at least two sub-band signals;

respectively performing frequency domain mapping on the frequency domain signals corresponding to the at least two sub-band signals to obtain frequency domain signals corresponding to the data to be sent;

performing first inverse Fourier transform on the frequency domain signal corresponding to the data to be transmitted to obtain a transmission signal;

and sending the transmission signal.

With reference to the implementation manner of the first aspect, in a first possible implementation manner of the first aspect, the separately performing frequency-domain filtering on the at least two subband signals includes: dividing each of the at least two sub-band signals into a plurality of data segments, respectively; respectively performing Fourier transform on a data segment of each of the at least two sub-band signals, wherein the ratio between the number of points of Fourier transform corresponding to any two sub-band signals in the at least two sub-band signals is equal to the ratio between the data rates of the any two sub-band signals; and respectively carrying out frequency domain filtering on the data segment of each sub-band signal in the at least two sub-band signals after Fourier transform.

With reference to the first aspect or the first possible implementation manner of the first aspect, in a second possible implementation manner of the first aspect, the sending the transmission signal includes: carrying out data combination on data segments in the transmitting signals; and carrying out data transmission on the transmitting signals after data combination.

With reference to the first aspect or the second possible implementation manner of the first aspect, in a third possible implementation manner of the first aspect, the dividing each of the at least two subband signals into a plurality of data segments respectively includes: adding T-1 0 to the heads of the at least two sub-band signals respectively, wherein T is the impulse response length of the filter corresponding to the at least two sub-band signals respectively; dividing the at least two added subband signals into a plurality of data segments with the length of L + T-1 respectively, wherein L is a positive integer, and T-1 overlapped data are arranged between every two adjacent data segments; the ratio of T-1 and the ratio of L + T-1 corresponding to any two subband signals in the at least two subband signals are equal, and equal to the ratio of the data rates of the any two subband signals.

With reference to the first aspect or any one of the first to third possible implementation manners of the first aspect, in a fourth possible implementation manner of the first aspect, the performing fourier transform on the data segment of each of the at least two subband signals respectively includes: determining the point number P of Fourier transform according to the data segment length L + T-1 of the at least two sub-band signals respectively, wherein P is L + T-1; and respectively carrying out P-point Fourier transform on each data segment of the at least two sub-band signals.

With reference to the first aspect or any one of the first to the fourth possible implementation manners of the first aspect, in a fifth possible implementation manner of the first aspect, the performing a first inverse fourier transform on the frequency domain signal corresponding to the data to be transmitted includes: and performing M-point first inverse Fourier transform on the frequency domain signal corresponding to the data to be transmitted, wherein the ratio of M to the number P of Fourier transform points corresponding to any sub-band signal in the at least two sub-band signals is equal to the ratio of the data rate of the transmission signal to the data rate of any sub-band signal.

With reference to the first aspect or any one of the first to the fifth possible implementation manners of the first aspect, in a sixth possible implementation manner of the first aspect, the performing data combination on the data segment in the transmission signal includes: according to the values of P and T corresponding to any one of the at least two sub-band signals and a formula

Determining the first K data of each data segment in the transmission signal; eliminating the first K data of each data segment in the transmitting signal; and splicing the residual data of each data segment in the transmitting signal in sequence.

With reference to the first aspect or any one of the first to the sixth possible implementation manners of the first aspect, in a seventh possible implementation manner of the first aspect, the generating at least two subband signals includes: dividing the data to be sent into at least two sub-band data in sequence; respectively carrying out carrier mapping on the at least two sub-band data; respectively carrying out second inverse Fourier transform on the at least two sub-band data subjected to carrier mapping, wherein the point number of the second inverse Fourier transform corresponding to any sub-band data in the at least two sub-band data is determined according to the data rate of a sub-band signal corresponding to any sub-band data; and respectively adding cyclic prefixes to the at least two sub-band data subjected to the second inverse Fourier transform to generate corresponding sub-band signals.

With reference to the first aspect or any one of the first to the seventh possible implementation manners of the first aspect, in an eighth possible implementation manner of the first aspect, a data rate of any one of the at least two subband signals is determined according to a bandwidth of the subband signal.

With reference to the first aspect or any one of the first to eighth possible implementation manners of the first aspect, in a ninth possible implementation manner of the first aspect, the performing frequency domain mapping on the frequency domain signals corresponding to the at least two subband signals respectively includes: and sequentially mapping the effective frequency bands of the at least two sub-band signals on different frequency points according to a frequency spectrum mapping rule.

With reference to the first aspect or any one of the first to ninth possible implementation manners of the first aspect, in a tenth possible implementation manner of the first aspect, the spectrum mapping rule reserves a guard interval between effective frequency bands of two adjacent subband signals.

In a second aspect, an apparatus for transmitting data is provided, including:

a subband signal generating unit, configured to generate at least two subband signals, where the at least two subband signals include data to be transmitted;

the frequency domain filtering unit is used for respectively carrying out frequency domain filtering on the at least two sub-band signals to obtain frequency domain signals corresponding to the at least two sub-band signals;

a frequency domain mapping unit, configured to perform frequency domain mapping on the frequency domain signals corresponding to the at least two sub-band signals, respectively, to obtain frequency domain signals corresponding to the data to be sent;

the first inverse Fourier transform unit is used for performing first inverse Fourier transform on the frequency domain signal corresponding to the data to be transmitted to obtain a transmitting signal;

and the sending unit is used for sending the transmitting signal.

With reference to the implementation manner of the second aspect, in a first possible implementation manner of the second aspect, the frequency domain filtering unit includes: a data segmentation module, configured to divide each of the at least two subband signals into a plurality of data segments; a fourier transform module, configured to perform fourier transform on a data segment of each of the at least two sub-band signals, respectively, where a ratio between points of fourier transform corresponding to any two sub-band signals in the at least two sub-band signals is equal to a ratio between data rates of the any two sub-band signals; and the filtering module is used for respectively carrying out frequency domain filtering on the data segment of each sub-band signal in the at least two sub-band signals after the Fourier transform.

With reference to the second aspect or the first possible implementation manner of the second aspect, in a second possible implementation manner of the second aspect, the sending unit includes: the data merging module is used for merging data of the data segments in the transmitting signals; and the data sending module is used for sending the data of the transmitting signals after the data combination.

With reference to the second aspect or the second possible implementation manner of the second aspect, in a third possible implementation manner of the second aspect, the data segmentation module is specifically configured to: adding T-1 0 in the head of each of the at least two sub-band signals, wherein T is the length of the impulse response of the frequency domain filter corresponding to each of the at least two sub-band signals; dividing the at least two added subband signals into a plurality of data segments with the length of L + T-1 respectively, wherein L is a positive integer, and T-1 overlapped data are arranged between every two adjacent data segments; the ratio of T corresponding to any two subband signals in the at least two subband signals is equal to the ratio of L + T-1, and is equal to the ratio of the data rates of the any two subband signals.

With reference to the second aspect or any one of the first to third possible implementation manners of the second aspect, in a fourth possible implementation manner of the second aspect, the fourier transform module is specifically configured to: determining the point number P of Fourier transform according to the data segment length L + T-1 of the at least two sub-band signals respectively, wherein P is L + T-1; and respectively carrying out P-point Fourier transform on each data segment of the at least two sub-band signals.

With reference to the second aspect or any one of the first to the fourth possible implementation manners of the second aspect, in a fifth possible implementation manner of the second aspect, the first inverse fourier transform unit is specifically configured to: and performing M-point first inverse Fourier transform on the frequency domain signal corresponding to the data to be transmitted, wherein the ratio of M to the number P of Fourier transform points corresponding to any sub-band signal in the at least two sub-band signals is equal to the ratio of the data rate of the transmission signal to the data rate of any sub-band signal.

With reference to the second aspect or any one of the first to fifth possible implementation manners of the second aspect, in a sixth possible implementation manner of the second aspect, the data merging module is specifically configured to: according to the values of P and T corresponding to any one of the at least two sub-band signals and a formula

With reference to the second aspect or any one of the first to the sixth possible implementation manners of the second aspect, in a seventh possible implementation manner of the second aspect, the subband signal generating unit includes: a sub-band dividing module, configured to divide the data to be sent into at least two sub-band data in sequence; a carrier mapping module, configured to perform carrier mapping on the at least two sub-band data respectively; the second inverse Fourier transform module is used for respectively performing second inverse Fourier transform on the at least two sub-band data subjected to carrier mapping, wherein the number of points of the second inverse Fourier transform corresponding to any sub-band data in the at least two sub-band data is determined according to the data rate of a sub-band signal corresponding to any sub-band data; and the cyclic prefix adding module is used for respectively adding cyclic prefixes to the at least two sub-band data subjected to the second inverse Fourier transform to generate corresponding sub-band signals.

With reference to the second aspect or any one of the first to the seventh possible implementation manners of the second aspect, in an eighth possible implementation manner of the second aspect, the data rate of any one of the at least two subband signals is determined according to a bandwidth of the subband signal.

With reference to the second aspect or any one of the first to the eighth possible implementation manners of the second aspect, in a ninth possible implementation manner of the second aspect, the frequency domain mapping unit is specifically configured to: and sequentially mapping the effective frequency bands of the at least two sub-band signals on different frequency points according to a frequency spectrum mapping rule.

With reference to the second aspect or any one of the first to the ninth possible implementation manners of the second aspect, in a tenth possible implementation manner of the second aspect, the spectrum mapping rule reserves a guard interval between effective frequency bands of two adjacent subband signals.

In a third aspect, a transmitter is provided, including: a transmitter, a memory, and a processor coupled with the memory; the memory stores a software program; the processor, by executing the software program, is to:

the transmitter is used for transmitting the transmission signal.

With reference to the implementation manner of the third aspect, in a first possible implementation manner of the third aspect, the processor is specifically configured to: dividing each of the at least two sub-band signals into a plurality of data segments, respectively; respectively performing Fourier transform on a data segment of each of the at least two sub-band signals, wherein the ratio between the number of points of Fourier transform corresponding to any two sub-band signals in the at least two sub-band signals is equal to the ratio between the data rates of the any two sub-band signals; and respectively carrying out frequency domain filtering on the data segment of each sub-band signal in the at least two sub-band signals after Fourier transform.

With reference to the third aspect or the first possible implementation manner of the third aspect, in a second possible implementation manner of the third aspect, the transmitter is specifically configured to: carrying out data combination on data segments in the transmitting signals; and carrying out data transmission on the transmitting signals after data combination.

With reference to the third aspect or the second possible implementation manner of the third aspect, in a third possible implementation manner of the third aspect, the processor is further specifically configured to: adding T-1 0 to the heads of the at least two sub-band signals respectively, wherein T is the impulse response length of the filter corresponding to the at least two sub-band signals respectively; dividing the at least two added subband signals into a plurality of data segments with the length of L + T-1 respectively, wherein L is a positive integer, and T-1 overlapped data are arranged between every two adjacent data segments; the ratio of T-1 and the ratio of L + T-1 corresponding to any two subband signals in the at least two subband signals are equal, and equal to the ratio of the data rates of the any two subband signals.

With reference to the third aspect, or any one of the first to third possible implementation manners of the third aspect, in a fourth possible implementation manner of the third aspect, the processor is specifically further configured to: determining the point number P of Fourier transform according to the data segment length L + T-1 of the at least two sub-band signals respectively, wherein P is L + T-1; and respectively carrying out P-point Fourier transform on each data segment of the at least two sub-band signals.

With reference to the third aspect or any one of the first to fourth possible implementation manners of the third aspect, in a fifth possible implementation manner of the third aspect, the processor is specifically configured to: and performing M-point first inverse Fourier transform on the frequency domain signal corresponding to the data to be transmitted, wherein the ratio of M to the number P of Fourier transform points corresponding to any sub-band signal in the at least two sub-band signals is equal to the ratio of the data rate of the transmission signal to the data rate of any sub-band signal.

In combination with the thirdIn a sixth possible implementation manner of the third aspect, the transmitter is further specifically configured to: according to the values of P and T corresponding to any one of the at least two sub-band signals and a formula

With reference to the third aspect or any one of the first to sixth possible implementation manners of the third aspect, in a seventh possible implementation manner of the third aspect, the processor is specifically configured to: dividing the data to be sent into at least two sub-band data in sequence; respectively carrying out carrier mapping on the at least two sub-band data; respectively carrying out second inverse Fourier transform on the at least two sub-band data subjected to carrier mapping, wherein the point number of the second inverse Fourier transform corresponding to any sub-band data in the at least two sub-band data is determined according to the data rate of a sub-band signal corresponding to the sub-band data; and respectively adding cyclic prefixes to the at least two sub-band data subjected to the second inverse Fourier transform to generate corresponding sub-band signals.

With reference to the third aspect or any one of the first to seventh possible implementation manners of the third aspect, in an eighth possible implementation manner of the third aspect, the data rate of any one of the at least two subband signals is determined according to a bandwidth of the subband signal.

With reference to the third aspect or any one of the first to eighth possible implementation manners of the third aspect, in a ninth possible implementation manner of the third aspect, the processor is specifically configured to: and sequentially mapping the effective frequency bands of the at least two sub-band signals on different frequency points according to a frequency spectrum mapping rule.

With reference to the third aspect or any one of the first to ninth possible implementation manners of the third aspect, in a tenth possible implementation manner of the third aspect, the spectrum mapping rule reserves a guard interval between effective frequency bands of two adjacent subband signals.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to these drawings without creative efforts.

Fig. 1 is a schematic diagram of a structure of a related art F-OFDM transmitter;

fig. 2 is a flowchart of a method for transmitting data according to an embodiment of the present invention;

fig. 3 is a flowchart of another method for transmitting data according to an embodiment of the present invention;

FIG. 4 is a diagram of data segmentation for a subband signal;

FIG. 5 is a diagram illustrating the signal amplitude of a sub-band signal after FFT;

FIG. 6 is a schematic diagram of the signal amplitude of a subband signal after frequency domain filtering;

FIG. 7 is a schematic representation of the recombination of the transmitted signals;

FIG. 8 is a schematic diagram of frequency domain mapping of a subband signal;

FIG. 9 is a schematic diagram of frequency domain mapping of another subband signal;

fig. 10 is a schematic diagram of an apparatus for transmitting data according to an embodiment of the present invention;

fig. 11 is a schematic structural diagram of a subband signal generating unit 101;

fig. 12 is a schematic diagram of another apparatus for transmitting data according to an embodiment of the present invention;

fig. 13 is a schematic diagram of a transmitter according to an embodiment of the present invention.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

The terms "first," "second," and the like in the following embodiments of the present invention are used for distinguishing between similar elements and not necessarily for describing a particular sequential or chronological order. It will be appreciated that the data so used may be interchanged under appropriate circumstances such that the embodiments described herein may be practiced otherwise than as specifically illustrated or described herein.

The OFDM has been widely used in the Wireless communication systems such as the Long Term Evolution (Long Term Evolution, 4G LTE) system and the Wireless Fidelity (Wi-Fi) system in the fourth Generation mobile communication technology due to its advantages of high transmission efficiency, simple implementation, and easy combination with Multiple Input Multiple Output (MIMO). However, the traditional OFDM system has the disadvantages of high out-of-band leakage, strict synchronization requirement, and the like, and the whole bandwidth only supports one waveform parameter. The basic waveform requirement of the fifth Generation mobile communication technology (the5th Generation mobile communication technology, abbreviated as 5G) can support rich service scenarios, the requirements of each service scenario on waveform parameters are different, the waveform parameters can be dynamically selected and configured according to the service scenarios, and meanwhile, the advantages of the conventional OFDM can be considered. F-OFDM is a waveform technology capable of meeting the 5G requirement, fig. 1 is a schematic diagram of a structure of an F-OFDM transmitter in the related art, and as shown in fig. 1, a system bandwidth is divided into a plurality of sub-bands: sub-band data 1, sub-band data 2, … … and sub-band data N, wherein only extremely low guard band overhead exists among the sub-bands, and each sub-band is configured with different waveform parameters according to the actual service scene requirements. And each sub-band independently performs sub-carrier mapping, IFFT conversion, cyclic prefix adding and filtering operation, so that decoupling of the waveform of each sub-band is realized, and 5G dynamic soft air interface parameter configuration according to service requirements is supported.

The method for sending data provided by the embodiment of the present invention may be specifically applicable to downlink data transmission from a base station (evolution Node B, eNB for short) to a UE, and may also be applicable to uplink data transmission from the UE to the eNB. The main body of the method may be the eNB side transmitter or the UE side transmitter.

Fig. 2 is a flowchart of a method for sending data according to an embodiment of the present invention, and as shown in fig. 2, the method for sending data according to the embodiment includes the following steps:

s21, generating at least two sub-band signals, the at least two sub-band signals including data to be transmitted;

s22, respectively carrying out frequency domain filtering on the at least two sub-band signals to obtain frequency domain signals corresponding to the at least two sub-band signals;

s23, frequency domain mapping is respectively carried out on the frequency domain signals corresponding to the at least two sub-band signals, and frequency domain signals corresponding to data to be sent are obtained;

s24, performing inverse Fourier transform on the frequency domain signal corresponding to the data to be transmitted to obtain a transmitting signal;

and S25, sending a transmitting signal.

In the present embodiment, the subband signal refers to an OFDM signal on a subband, but other types of signals are not excluded, such as a single Carrier signal and a Filter Bank Multiple Carrier (FBMC) signal. In order to describe the technical solution of the present invention more clearly, the present embodiment will exemplarily illustrate that the subband signal is an OFDM signal. It will be apparent that the examples are given for illustration and are not intended to limit the invention.

Illustratively, the at least two subband signals may be generated according to a correlation technique. As an alternative embodiment, the at least two subband signals may be generated according to a standard OFDM signal generation process. Specifically, S21 may include the following steps:

step 1, dividing data to be transmitted into at least two sub-band data in sequence;

step 2, respectively carrying out carrier mapping on at least two sub-band data;

step 3, performing inverse Fourier transform on the at least two sub-band data subjected to carrier mapping respectively;

and 4, respectively adding CP to the at least two sub-band data subjected to the Fourier inverse transformation to generate corresponding sub-band signals.

The role of subcarrier mapping is to map data to be transmitted on effective subcarriers. For example: the total number of subcarriers is 128, and the effective subcarriers are 100, then 100 data to be transmitted are mapped on the specific 100 subcarriers. The inverse fourier transform and CP adding operations are consistent with the OFDM signal processing method in the related art, that is, the inverse fourier transform here can be selected as IFFT. It should be noted that, in the present embodiment, in the sub-band signal generation process, each sub-band may perform IFFT with a smaller number of points. For convenience of description, the IFFT performed in the subband signal generating process is hereinafter referred to as a second IFFT.

It will be appreciated that the total bandwidth of the generated sub-band signal is the spectrum for the total number of sub-carriers, where the effective sub-carriers correspond to the effective bandwidth and the remainder are the out-of-band components. In order to suppress and prevent interference between subbands, in this embodiment, frequency domain filtering is performed on each subband signal, frequency domain mapping is performed on the frequency domain signal corresponding to each subband signal after frequency domain filtering, so as to obtain a frequency domain signal corresponding to data to be transmitted, and then inverse fourier transform is performed on the frequency domain signal corresponding to the data to be transmitted. For convenience of description, the IFFT performed on the frequency domain signal corresponding to the data to be transmitted is referred to as a first IFFT hereinafter. On the one hand, the frequency domain signal can be converted back to the time domain by the first IFFT; on the other hand, the data rates of the respective subband signals can be unified by the first IFFT.

It is worth mentioning that each subband signal is low rate data, the so-called low rate being relative to the resulting high rate transmitted signal. For example, the final output data rate is 30.72MHz, and the signal rate for each sub-band may be less than 30.72 MHz.

Illustratively, the data rate of a subband signal may be determined based on parameters such as the bandwidth requirement of the subband and the subcarrier spacing. For example, assuming that the sub-carrier interval of sub-band 1 is 15KHz, it carries a small packet type service, and the number of users is not large, so the bandwidth requirement of the sub-band is small, and assuming that the bandwidth requirement is 100 sub-carrier widths, the data rate is 100 × 15KHz — 1.5 MHz. Similarly, the data rate of other subband signals can be determined by this method, and assuming that the subcarrier spacing of subband 2 is 15KHz and the bandwidth requirement is 600 subcarriers, the data rate is 600 × 15 KHz-9 MHz.

In general, in order to facilitate the first IFFT and the second IFFT, the number of subcarriers of each subband signal needs to be an integer power of 2. In the present embodiment, taking subband 1 as an example, the number of reasonable subcarriers should be 128, i.e. greater than 100, and is the minimum value of 2 raised to the power of an integer. At this time, the total number of subcarriers of subband 1 is 128, and the number of effective subcarriers is 100, the data rate of subband 1 is finally determined to be 1.92MHz, i.e., 128 × 15KHz is 1.92 MHz. Similarly, if the total number of subcarriers of subband 2 is 1024 and the number of effective subcarriers is 600, the data rate of subband 2 is finally determined to be 15.36MHz, i.e., 1024 × 15KHz is 15.36 MHz.

As described above, in the present embodiment, in the subband signal generating process, each subband can be subjected to IFFT with a small number of points. Specifically, the number of the second IFFT points performed on each subband signal may be determined according to the data rate of the corresponding subband.

Since the data rates of the sub-band signals are unified through the first IFFT in this embodiment, the number of points M of the first IFFT can be determined according to the total number of sub-carriers of one of the sub-band signals, the data rate, and the data rate of the final transmission signal. For example, if the total number of subcarriers in subband 1 is 128, the data rate of subband 1 is 1.92MHz, and the data rate of the final transmission signal is 30.72MHz, the number of points of the first IFFT is 128 × (30.72/1.92) ═ 2048 points. Similarly, the same result will be obtained from the total number of subcarriers for subband 2, the data rate, and the data rate of the final transmitted signal, i.e., 1024 × (30.72/15.36) ═ 2048 points.

In the method for sending data provided in this embodiment, for each sub-band signal, the sub-carrier interval, the sub-band width, and the CP length of the sub-band signal may be adaptively adjusted to adapt to channel scenarios and service types of different UEs, and the data rate of each sub-band signal is unified by performing frequency domain filtering and frequency domain mapping on each sub-band signal, so that the filtering of each sub-band signal may be performed at a lower sampling rate, and compared with the related art in which the filtering of each sub-band needs to be performed at a higher sampling rate, the complexity may be effectively reduced.

In addition, in the present embodiment, by performing frequency domain filtering on each subband signal, complexity can be effectively reduced compared to time domain filtering in the related art. In addition, in the sub-band signal generation process, the second IFFT with a smaller number of points may be used for each sub-band, which may further reduce complexity.

Fig. 3 is a flowchart of another method for sending data according to an embodiment of the present invention, where in this embodiment, based on the embodiment shown in fig. 2, S22 may specifically include the following steps:

s221, dividing each sub-band signal of at least two sub-band signals into a plurality of data segments;

s222, respectively carrying out Fourier transform on the data segment of each sub-band signal in at least two sub-band signals;

and S223, respectively carrying out frequency domain filtering on the data segment of each sub-band signal in the at least two sub-band signals after Fourier transform.

Further, S25 may specifically include the following steps:

s251, data merging is carried out on the data segments in the transmitting signals;

and S252, transmitting the data of the transmitting signals after data combination.

The filtering operation is usually implemented in the time domain by linear convolution, and assuming that the filter impulse response is h (n) and the length is T, the filtering operation on the signal x (n) can be expressed as:

where y (n) is the filtered output signal.

Assuming that the total length of the data is N, the total number of complex multiplications is about NT. In the F-OFDM system, in order to control the inter-subband interference, the impulse response length T of the filter is usually large, and the calculation complexity is very high. In order to reduce complexity, the embodiment of the invention adopts low-complexity frequency domain filtering to realize filtering of the sub-band signals.

It can be understood that a Finite Impulse Response (FIR) filter has the advantages of linear phase and easy design compared with an Infinite Impulse Response (IIR) filter, and in addition, the FIR filter can adopt a Fast Fourier Transform (FFT) algorithm, and the operation speed can be much faster under the condition of the same order. The subband signals are continuous, so that the purpose of data segmentation is to divide the continuous data into data blocks which are convenient for signal processing and meet a certain length condition, and preparation is made for realizing frequency domain filtering. In this embodiment, the processing methods of all the subbands are the same, and the difference lies in the selection of specific parameters, which will be described in further detail below by taking one subband as an example.

FIG. 4 is a schematic diagram of data segmentation of a subband signal, and as shown in FIG. 4, T-1 0 s are added to the head of the subband signal, where T is the impulse response length of the filter corresponding to the subband signal, and it is assumed that the impulse response of the filter is h (n), where n is greater than or equal to 1 and less than or equal to T. And then segmenting the data, wherein the length of each segment is L + T-1, L is any positive integer, and T-1 data in two continuous segments of data are overlapped. Recording segmentThe last i-th data is x_i(n),1≤n≤L+T-1。

It is worth mentioning that if the data is of finite length, the length of the last segment may be less than L + T-1, and L + T-1 can be achieved by adding 0 to the tail. The choice of L is an implementation issue. Preferably, L is chosen such that L + T-1 is an integer power of 2, i.e., L + T-1 is 2^NAnd FFT is conveniently carried out.

The specific lengths of T and L are not limited in this embodiment, but the lengths should satisfy that the ratio of T-1 and the ratio of L + T-1 of different sub-bands are equal and equal to the ratio of data rates between different sub-bands. For example: assume that T-1 for subband 1 has a size of 64 and L + T-1 has a size of 128; since the ratio of the data rates of sub-band 1 and sub-band 2 is 1.92/15.56-1/8; thus, the size of T-1 for sub-band 2 should be chosen to be 512 (i.e., 64X 8) and the L + T-1 size should be 1024 (i.e., 128X 8).

For data segments, i.e. x, of the segmented subband signal_i(n), n is more than or equal to 1 and less than or equal to L + T-1, FFT is carried out, and the purpose of FFT is also to prepare for realizing frequency domain filtering. Fig. 5 is a schematic diagram of signal amplitude of a subband signal after FFT, and as shown in fig. 5, we refer to data samples with more significant amplitude values as effective bandwidth, and data samples with lower amplitude values on both sides of the effective bandwidth as out-of-band component, and all data samples are referred to as total bandwidth, obviously, the width of the total bandwidth is determined by the total number of subcarriers of the subband, and the position and width of the effective bandwidth are determined by the effective subcarriers of the subband. For example, since the effective number of sub-band 1 is 100 and the total number of sub-carriers is 128, assuming that after performing 128-point FFT, the total bandwidth of sub-band 1 is formed by 128 frequency samples, and its effective bandwidth is 100 frequency samples at the center. Similarly, assume that after subband 2 undergoes 1024-point FFT, the total bandwidth consists of 1024 frequency samples, and its effective bandwidth is the 600 frequency samples at the center.

As a preferred embodiment, the number P of FFT points may be determined according to the length of the data segment of each sub-band signal after segmentation, for example, P ═ L + T-1. Theoretically, the ratio of the number P of FFT performed on the data segment of each sub-band signal to the number M of first IFFT should be equal to the ratio of the data rate of the transmission signal to the data rate of each sub-band signal, so that the sub-band signals with different data rates have uniform data rates after passing through the first IFFT, that is, the data rates of the transmission signals. It will further be appreciated that the number of points of the first IFFT, determined according to the data rate of any sub-band and the number of points of its FFT, and the data rate of the transmitted signal, is the same. For example, if the FFT size of subband 1 is 128 and the data rate of subband 1 is 1.92MHz, the first IFFT size M should be 128 × (30.72/1.92) × 2048 points. Similarly, the FFT size of subband 2 is 1024, and the data rate of subband 2 is 15.36MHz, then the first IFFT size M should be 1024 × (30.72/15.36) ═ 2048 points.

Further, the data segment of the sub-band signal after the FFT is subjected to frequency domain filtering. Specifically, the FFT-processed data is multiplied by the frequency domain response of the filter, which can be processed by the FFT_L+T-1{ h (n) }, where h (n) is the time domain impulse response of the filter, its length is T, FFT_L+T-1{ h (n) } denotes FFT conversion of h (n) at L + T-1 point. Fig. 6 is a schematic diagram of the amplitude of a frequency-domain filtered signal of a subband signal, wherein the amplitude of the out-of-band portion is significantly reduced compared to the amplitude of the signal before filtering as shown in fig. 5.

It can be understood that for x_i(n), n is more than or equal to 1 and less than or equal to L + T-1, FFT of L + T-1 point is carried out, the FFT is multiplied by the frequency domain response of the filter, the frequency domain response is converted back to the time domain through the first IFFT, and the obtained signal can be expressed as: y is_i(n)＝IFFT_M{FFT_L+T-1{x_i(n)}FFT_L+T-1{ h (n) }, where the frequency domain response of the filter FFT_L+T-1{ h (n) } is constant in one filtering operation, and only needs to be calculated once, or calculated in advance and stored.

Fig. 7 is a schematic diagram of a recombination of the transmitted signals, please refer to fig. 7. Since frequency domain multiplication is equivalent to time domain cyclic convolution, pass y_i(n)＝IFFT_M{FFT_L+T-1{x_i(n)}FFT_L+T-1Y calculated from { h (n) } }_i(n) corresponds to x_i(n) and h (n). However, as can be seen from the properties of the circular convolution, y_iX is contained in the first K data of (n)_i(n) a contribution of last T-1 data, wherein

Therefore y_iThe first K data of (n) belong to the result of cyclic convolution, and the rest are the result of equivalent linear convolution.

It should be noted that, as described above, in this embodiment, the ratio of T-1 and the ratio of P corresponding to any two subband signals are equal, so the parameters P and T for determining K may be the number of FFT points and the impulse response length of the filter corresponding to any subband signal.

As a preferred embodiment, all data segments y may be divided_iAnd (n) eliminating the first K data, splicing the residual data of the data segments according to the sequence, and finally obtaining the equivalent linear convolution result. Obviously, the ratio of T-1 and the ratio of P corresponding to any two subband signals are equal, so that the length of data to be removed in each data segment in the final transmission signal is the same.

The specific lengths of T and L should be such that the ratio of T-1 and L + T-1 for the different subbands are equal and equal to the ratio of the data rates between the different subbands, as described above. It is worth mentioning that L should exceed T-1 by a factor of several, since y is filtered_iK data in (n) are discarded, and if L is selected too small, the ratio of invalid calculation is large.

In this embodiment, the FFT is performed if the frequency domain response of the calculation filter is omitted_L+T-1{ h (n) } required complexity. The number of complex multiplications required to perform frequency domain filtering on data of length N is approximately

The multiplication complexity NT required for the time-domain filtering is approximately proportional to

For example, when T is 512 and L is 513, the multiplication number of the frequency domain filtering is about 0.08 times of the time domain filtering. Therefore, the method for sending the data provided by the embodiment can effectively reduce the complexity.

In a possible implementation manner of this embodiment, when performing spectrum mapping on the frequency domain signals corresponding to the at least two subband signals (S23), the effective bands of the at least two subband signals may be mapped on different frequency points according to a spectrum mapping rule.

And mapping the signals of each sub-band signal after frequency domain filtering on different frequency points. The effective bandwidth of each sub-band signal is mapped on different frequency positions according to a predefined spectrum mapping rule, and the out-band component is completely or partially overlapped with the spectrum of other sub-bands.

For example, assuming that the number of points of the first IFFT is 2048, it can be known from the property of the IFFT that 2048 data samples of the input IFFT represent 2048 different frequency locations at equal intervals, respectively. For example, the frequency-domain filtered signal for subband 1 has 128 data samples with an effective bandwidth of 100 data samples, and the frequency-domain filtered signal for subband 2 has 1024 data samples with an effective bandwidth of 600 data samples.

Fig. 8 is a schematic diagram of frequency domain mapping of a subband signal, as shown in fig. 8, where the spectrum mapping rule is that no guard interval is reserved between adjacent subbands. For example, 100 data samples of the effective bandwidth of subband 1 are mapped at frequency positions numbered Z to number Z +99, and 600 data samples of the effective bandwidth of subband 2 are mapped at frequency positions numbered Z +100 to Z +699, where Z represents the number of the starting frequency position of subband 1. The samples of their out-of-band components overlap with other sub-bands, and a plurality of samples overlapping with each other may be directly added in signal processing.

Fig. 9 is a schematic diagram of frequency domain mapping of another subband signal, as shown in fig. 9, when the spectrum mapping rule is to reserve guard intervals between the effective bands of adjacent subbands. The difference from fig. 8 is that Δ null frequency positions exist between the effective frequency bands of adjacent sub-bands as guard intervals. It can be understood that when a guard interval exists between the effective frequency bands of adjacent sub-bands, the interference between the sub-bands can be effectively reduced.

Based on the method for transmitting data provided by the above embodiment of the present invention, the data rates of the respective sub-band signals are unified by performing frequency domain filtering and frequency domain mapping on the respective sub-band signals, so that the filtering of the respective sub-band signals can be performed at a lower sampling rate, and the complexity can be effectively reduced compared with the related art in which the filtering of the respective sub-band signals needs to be performed at a higher sampling rate. By performing frequency domain filtering on each sub-band signal, the computational complexity of the algorithm can be effectively reduced compared with time domain filtering in the related art. By means of frequency domain mapping and reserving guard intervals between the effective frequency bands of adjacent sub-bands, interference among the sub-bands can be effectively reduced.

Fig. 10 is a schematic diagram of an apparatus for sending data according to an embodiment of the present invention, where the apparatus may be specifically configured in a base station, or may be configured in a user equipment, and may be configured to implement the method for sending data according to the embodiment of fig. 2 or fig. 3 of the present invention, which is not described herein again. As shown in fig. 10, the data transmission apparatus includes a subband signal generating section 101, a frequency domain filtering section 102, a frequency domain mapping section 103, an inverse fourier transform section 104, and a transmitting section 105.

The subband signal generating unit 101 may be configured to generate at least two subband signals, where the at least two subband signals include data to be transmitted. The frequency domain filtering unit 102 may be configured to perform frequency domain filtering on the at least two sub-band signals, respectively, to obtain frequency domain signals corresponding to the at least two sub-band signals. The frequency domain mapping unit 103 may be configured to perform frequency domain mapping on the frequency domain signals corresponding to the at least two sub-band signals, respectively, to obtain frequency domain signals corresponding to data to be sent. The inverse fourier transform unit 104 may be configured to perform a first inverse fourier transform on the frequency domain signal corresponding to the data to be transmitted, so as to obtain a transmission signal. The transmitting unit 105 may be used to transmit a transmission signal.

In practical applications, the subband signal generating unit 101 may be a device for generating an OFDM signal in the related art, and fig. 11 is a schematic structural diagram of the subband signal generating unit 101, as shown in fig. 11, the subband signal generating unit includes a subband dividing module 111,

carrier mapping modules

1121, 1122, … …, 112N,

IFFT modules

1131, 1132, … …, 113N and

CP adding modules

1141, 1142, … …, 114N.

The subband dividing module 111 may be configured to sequentially divide data to be transmitted into at least two subband data. The

carrier mapping modules

1121, 1122, … …, 112N may be used to perform carrier mapping on the sub-band data, respectively. The

IFFT modules

1131, 1132, … …, and 113N may be configured to perform second inverse fourier transform on each sub-band data after carrier mapping, where the number of points of the second inverse fourier transform corresponding to any one of the at least two sub-band data is determined according to the data rate of the sub-band. The

CP adding modules

1141, 1142, … …, and 114N may be configured to add a CP to each sub-band data after the second inverse fourier transform, respectively, to generate corresponding sub-band signals.

It should be noted that, in this embodiment, the data rate of each subband signal may be determined according to the bandwidth corresponding to the subband signal.

In practical applications, the frequency domain mapping unit 103 may be specifically configured to sequentially map the effective frequency bands of the sub-band signals on different frequency points according to a spectrum mapping rule.

In a preferred embodiment, the spectrum mapping rule herein may reserve a guard interval between the effective bands of two adjacent subband signals to reduce interference between the subbands.

The apparatus for sending data provided in this embodiment may be used to implement the method for sending data provided in the embodiments shown in fig. 2 or fig. 4 of the present invention, and the implementation principle and the technical effect are similar, which are not described herein again.

Fig. 12 is a schematic diagram of another apparatus for sending data according to an embodiment of the present invention, and in this embodiment, on the basis of the embodiment shown in fig. 10, the frequency domain filtering unit 102 may specifically include

data segmentation modules

10211, 10212, … …, and 1021N, fourier transform modules (FFT modules) 10221, 10222, … …, and 1022N, and

filtering modules

10231, 10232, … …, and 1023N. The

data segmentation modules

10211, 10212, … …, and 1021N may be configured to divide each subband signal into a plurality of data segments. The

FFT modules

10221, 10222, … …, 1022N may be configured to perform fourier transform on data segments of the respective sub-band signals, respectively, where a ratio between points of the fourier transform corresponding to any two sub-band signals of at least two sub-band signals is equal to a ratio between data rates of the any two sub-band signals. The

filtering modules

10231, 10232, … …, 1023N may be used to frequency-domain filter the data segments of the respective sub-band signals after fourier transformation.

Further, the sending unit 105 may specifically include a data merging module 1051 and a data sending module 1052. The data merging module 1051 may be configured to merge data segments in the transmission signal; the data sending module 1052 may be configured to send data to the transmission signal after data combination.

In practical applications, the

data segmentation modules

10211, 10212, … …, 1021N may be specifically configured to: adding T-1 0 s to the head of the corresponding sub-band signal, wherein T is the length of the impulse response of the filter corresponding to the corresponding sub-band signal; dividing the added subband signal into a plurality of data segments with the length of L + T-1, wherein L is a positive integer, and T-1 overlapped data are arranged between every two adjacent data segments;

it is worth mentioning that the ratio of T-1 and the ratio of L + T-1 corresponding to any two subband signals are equal and equal to the ratio of the data rates of the any two subband signals.

Further, the

FFT modules

10221, 10222, … …, 1022N may be specifically configured to: and determining the point number P of Fourier transform according to the data segment length L + T-1 of the corresponding sub-band signal, wherein P is L + T-1, and performing P-point Fourier transform on each data segment of the sub-band signal.

Further, in practical applications, the inverse fourier transform unit 104 may be specifically configured to: and performing M-point first inverse Fourier transform on the frequency domain signal corresponding to the data to be transmitted. Wherein, the ratio of M to the number P of fourier transformed points corresponding to any one of the subband signals is equal to the ratio of the data rate of the transmitted signal to the data rate of the subband signal.

Further, in practical applications, the data merging module 1051 may be specifically configured to: according to the values of P and T corresponding to any one of at least two sub-band signals and formula

Determining the first K data of each data segment in the transmission signal; and eliminating the first K data of each data segment in the transmitting signal, and sequentially splicing the residual data of each data segment in the transmitting signal.

Fig. 13 is a schematic diagram of a transmitter according to an embodiment of the present invention, where the transmitter may be specifically configured in a base station, and may be used to implement the method for sending data according to the embodiment shown in fig. 2 or fig. 3, which is not described herein again. As shown in fig. 12, the present embodiment provides a transmitter including a transmitter 131, a memory 132, and a processor 133, wherein the processor 133 is coupled to the memory 132.

In particular, the memory 132 stores software programs, and the processor 133 may be configured to: generating at least two subband signals, wherein the at least two subband signals comprise data to be transmitted; respectively carrying out frequency domain filtering on the at least two sub-band signals to obtain frequency domain signals corresponding to the at least two sub-band signals; respectively performing frequency domain mapping on the frequency domain signals corresponding to the at least two sub-band signals to obtain frequency domain signals corresponding to the data to be sent; and performing first inverse Fourier transform on the frequency domain signal corresponding to the data to be transmitted to obtain a transmitting signal. Transmitter 131 may be used to transmit the transmit signal.

In practical applications, the processor 133 may be specifically configured to: dividing each sub-band signal of at least two sub-band signals into a plurality of data segments respectively; respectively carrying out Fourier transform on a data segment of each sub-band signal in at least two sub-band signals; and respectively carrying out frequency domain filtering on the data segment of each sub-band signal in the at least two sub-band signals after Fourier transform.

Further, the transmitter 131 may specifically be configured to: carrying out data combination on data segments in the transmitting signals; and carrying out data transmission on the transmission signals subjected to data combination.

It should be noted that the ratio between the number of fourier transform points corresponding to any two of the above subband signals is equal to the ratio between the data rates of any two of the subband signals.

Further, in practical applications, the processor 133 may be further configured to: for each sub-band signal, adding T-1 0 to the head of the sub-band signal, wherein T is the impulse response length of the filter corresponding to the sub-band signal; dividing the added subband signal into a plurality of data segments with the length of L + T-1, wherein L is a positive integer, and T-1 overlapped data are arranged between every two adjacent data segments; the ratio of T-1 and the ratio of L + T-1 corresponding to any two subband signals in the at least two subband signals are equal, and equal to the ratio of the data rates of the any two subband signals.

Further, the processor 133 may be specifically configured to: for each sub-band signal, determining the point number P of Fourier transform according to the data segment length L + T-1 of the sub-band signal, wherein P is L + T-1; a P-point fourier transform is performed on each data segment of the subband signal.

Further, the processor 133 may be specifically configured to: and performing M-point first inverse Fourier transform on the frequency domain signal corresponding to the data to be transmitted, wherein the ratio of M to the number P of Fourier transform points corresponding to any sub-band signal in at least two sub-band signals is equal to the ratio of the data rate of the transmitted signal to the data rate of the sub-band signal.

Accordingly, the transmitter 131 may be further specifically configured to: according to the values of P and T corresponding to any one of at least two sub-band signals and formula

Determining the first K data of each data segment in the transmission signal; eliminating the first K data of each data segment in the transmitting signal; and splicing the residual data of each data segment in the transmission signal in sequence.

In practical applications, the processor 133 is further configured to: dividing data to be transmitted into at least two sub-band data in sequence; respectively carrying out carrier mapping on at least two sub-band data; respectively carrying out second inverse Fourier transform on the at least two sub-band data subjected to carrier mapping, wherein the point number of the second inverse Fourier transform corresponding to any sub-band data in the at least two sub-band data is determined according to the data rate of the sub-band; and respectively adding CP to the at least two sub-band data subjected to the second inverse Fourier transform to generate corresponding sub-band signals.

In this embodiment, the data rate of each subband signal may be determined according to the bandwidth of the subband.

In practical applications, the processor 133 is further configured to: and sequentially mapping the effective frequency band of each sub-band signal on different frequency points according to a spectrum mapping rule.

The transmitter provided in this embodiment may be used to implement the method for sending data provided in the embodiments shown in fig. 2 or fig. 4 of the present invention, and the implementation principle and technical effect are similar, which are not described herein again.

Those of ordinary skill in the art will understand that: all or a portion of the steps of implementing the above-described method embodiments may be performed by hardware associated with program instructions. The program may be stored in a computer-readable storage medium. When executed, the program performs steps comprising the method embodiments described above; and the aforementioned storage medium includes: various media that can store program codes, such as ROM, RAM, magnetic or optical disks.

Finally, it should be noted that: the above embodiments are only used to illustrate the technical solution of the present invention, and not to limit the same; while the invention has been described in detail and with reference to the foregoing embodiments, it will be understood by those skilled in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some or all of the technical features may be equivalently replaced; and the modifications or the substitutions do not make the essence of the corresponding technical solutions depart from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method of transmitting data, comprising:

transmitting the transmission signal;

the frequency domain filtering the at least two sub-band signals respectively comprises:

dividing each of the at least two sub-band signals into a plurality of data segments, respectively;

respectively performing Fourier transform on a data segment of each of the at least two sub-band signals, wherein the ratio between the number of points of Fourier transform corresponding to any two sub-band signals in the at least two sub-band signals is equal to the ratio between the data rates of any two sub-band signals;

and respectively carrying out frequency domain filtering on the data segment of each sub-band signal in the at least two sub-band signals after Fourier transform.

2. The method of claim 1, wherein said sending the transmission signal comprises:

carrying out data combination on data segments in the transmitting signals;

and carrying out data transmission on the transmitting signals after data combination.

3. The method according to claim 1 or 2, wherein the separately dividing each of the at least two subband signals into a plurality of data segments comprises:

adding T-1 0 to the heads of the at least two sub-band signals respectively, wherein T is the impulse response length of the filter corresponding to the at least two sub-band signals respectively;

dividing the at least two added subband signals into a plurality of data segments with the length of L + T-1 respectively, wherein L is a positive integer, and T-1 overlapped data are arranged between every two adjacent data segments;

the ratio of T-1 and the ratio of L + T-1 corresponding to any two subband signals in the at least two subband signals are equal, and equal to the ratio of the data rates of any two subband signals.

4. The method of claim 3, wherein the separately Fourier transforming the data segments of each of the at least two sub-band signals comprises:

determining the point number P of Fourier transform according to the data segment length L + T-1 of the at least two sub-band signals respectively, wherein P is L + T-1;

and respectively carrying out P-point Fourier transform on each data segment of the at least two sub-band signals.

5. The method according to claim 4, wherein the performing a first inverse fourier transform on the frequency-domain signal corresponding to the data to be transmitted comprises:

and performing M-point first inverse Fourier transform on the frequency domain signal corresponding to the data to be transmitted, wherein the ratio of M to the number P of Fourier transform points corresponding to any sub-band signal in the at least two sub-band signals is equal to the ratio of the data rate of the transmission signal to the data rate of any sub-band signal.

6. The method of claim 5, wherein the data combining the data segments in the transmission signal comprises:

according to the values of P and T corresponding to any one of the at least two sub-band signals and a formula

Determining the first K data of each data segment in the transmission signal;

eliminating the first K data of each data segment in the transmitting signal;

and splicing the residual data of each data segment in the transmitting signal in sequence.

7. The method of any of claims 1-2 and 4-6, wherein generating at least two subband signals comprises:

dividing the data to be sent into at least two sub-band data in sequence;

respectively carrying out carrier mapping on the at least two sub-band data;

respectively carrying out second inverse Fourier transform on the at least two sub-band data subjected to carrier mapping, wherein the point number of the second inverse Fourier transform corresponding to any sub-band data in the at least two sub-band data is determined according to the data rate of a sub-band signal corresponding to any sub-band data;

and respectively adding cyclic prefixes to the at least two sub-band data subjected to the second inverse Fourier transform to generate corresponding sub-band signals.

8. The method according to any of claims 1-2 and 4-6, wherein the data rate of any of said at least two subband signals is determined according to the bandwidth of said any subband signal.

9. The method according to any of claims 1-2 and 4-6, wherein the frequency domain mapping the frequency domain signals corresponding to the at least two sub-band signals respectively comprises:

and sequentially mapping the effective frequency bands of the at least two sub-band signals on different frequency points according to a frequency spectrum mapping rule.

10. The method of claim 9, wherein the spectrum mapping rule reserves a guard interval between the active bands of two adjacent subband signals.

11. An apparatus for transmitting data, comprising:

the inverse Fourier transform unit is used for performing first inverse Fourier transform on the frequency domain signal corresponding to the data to be transmitted to obtain a transmitting signal;

a transmitting unit for transmitting the transmission signal;

the frequency domain filtering unit includes:

a data segmentation module, configured to divide each of the at least two subband signals into a plurality of data segments;

a fourier transform module, configured to perform fourier transform on a data segment of each of the at least two sub-band signals, respectively, where a ratio between points of fourier transform corresponding to any two sub-band signals in the at least two sub-band signals is equal to a ratio between data rates of the any two sub-band signals;

and the filtering module is used for respectively carrying out frequency domain filtering on the data segment of each sub-band signal in the at least two sub-band signals after the Fourier transform.

12. The apparatus of claim 11, wherein the sending unit comprises:

the data merging module is used for merging data of the data segments in the transmitting signals;

and the data sending module is used for sending the data of the transmitting signals after the data combination.

13. The apparatus of claim 12, wherein the data segmentation module is specifically configured to:

adding T-1 0 in the head of each of the at least two sub-band signals, wherein T is the length of the impulse response of the frequency domain filter corresponding to each of the at least two sub-band signals;

14. The apparatus of claim 13, wherein the fourier transform module is specifically configured to:

15. The apparatus according to claim 14, wherein said inverse fourier transform unit is specifically configured to:

16. The apparatus of claim 15, wherein the data merging module is specifically configured to:

Determining the first K data of each data segment in the transmission signal;

eliminating the first K data of each data segment in the transmitting signal;

17. The apparatus according to any of claims 11-12, 14-16, wherein the subband signal generating unit comprises:

a sub-band dividing module, configured to divide the data to be sent into at least two sub-band data in sequence;

a carrier mapping module, configured to perform carrier mapping on the at least two sub-band data respectively;

the inverse Fourier transform module is used for respectively performing second inverse Fourier transform on the at least two sub-band data after carrier mapping, wherein the number of points of the second inverse Fourier transform corresponding to any sub-band data in the at least two sub-band data is determined according to the data rate of a sub-band signal corresponding to any sub-band data;

and the cyclic prefix adding module is used for respectively adding cyclic prefixes to the at least two sub-band data subjected to the second inverse Fourier transform to generate corresponding sub-band signals.

18. The apparatus according to any of claims 11-12, 14-16, wherein the data rate of any of said at least two subband signals is determined according to the bandwidth of said any subband signal.

19. The apparatus according to any of claims 11-12, 14-16, wherein the frequency domain mapping unit is specifically configured to:

20. The apparatus of claim 19, wherein the spectrum mapping rule reserves a guard interval between the active bands of two adjacent subband signals.

21. A transmitter, comprising: a transmitter, a memory, and a processor coupled with the memory;

the memory stores a software program;

the processor, by executing the software program, is to:

the transmitter is used for transmitting the transmission signal;

the processor is specifically configured to:

22. The transmitter according to claim 21, characterized in that the transmitter is specifically configured to:

carrying out data combination on data segments in the transmitting signals;

23. The transmitter according to claim 21 or 22, wherein the processor is further configured to:

24. The transmitter of claim 23, wherein the processor is further configured to:

25. The transmitter of claim 24, wherein the processor is further configured to:

26. The transmitter of claim 25, wherein the transmitter is further configured to:

Determining the first K data of each data segment in the transmission signal;

eliminating the first K data of each data segment in the transmitting signal;

27. The transmitter according to any of claims 21-22, 24-26, wherein the processor is specifically configured to:

dividing the data to be sent into at least two sub-band data in sequence;

respectively carrying out carrier mapping on the at least two sub-band data;

28. The transmitter according to any of claims 21-22, 24-26, wherein the data rate of any of said at least two sub-band signals is determined according to the bandwidth of said any sub-band signal.

29. The transmitter according to any of claims 21-22, 24-26, wherein the processor is further configured to: and sequentially mapping the effective frequency bands of the at least two sub-band signals on different frequency points according to a frequency spectrum mapping rule.

30. The transmitter of claim 29, wherein the spectrum mapping rule reserves a guard interval between the active bands of two adjacent subband signals.