CN106878221B

CN106878221B - Method and device for generating multi-carrier signal

Info

Publication number: CN106878221B
Application number: CN201510925556.6A
Authority: CN
Inventors: 黄琛; 胡留军; 辛雨
Original assignee: ZTE Corp
Current assignee: ZTE Corp
Priority date: 2015-12-14
Filing date: 2015-12-14
Publication date: 2021-08-06
Anticipated expiration: 2035-12-14
Also published as: CN106878221A; WO2017101459A1

Abstract

A generation method and generation device of multi-carrier signals; the generation method comprises the following steps: zero adding is carried out on one or more sections of single carrier signals, and signal transformation is carried out to obtain one or more transform domain signal sections; mapping the one or more transform domain signal segments to resource positions of one or more subbands to obtain one or more subband signals; respectively carrying out multi-carrier modulation and filtering on the one or more sub-band signals; and superposing the multi-carrier modulated and filtered sub-band signals. The invention can resist the influence caused by channel multipath time delay and propagation time delay and eliminate ISI.

Description

Method and device for generating multi-carrier signal

Technical Field

The present invention relates to the field of wireless communications, and in particular, to a method and an apparatus for generating a multi-carrier signal.

Background

In an LTE (Long Term Evolution) system and an LTE-a (Long Term Evolution-Advanced, Long Term Evolution-follow-up) system, OFDM (Orthogonal Frequency Division Multiplexing) is a basic technology for physical layer signal transmission. However, the sideband leakage of the OFDM signal is large, especially when there is a time offset and a frequency offset. This results in a large guard bandwidth between OFDM and other systems, and in order to reduce interference to other users, signals of each user equipment of the OFDM system need to be strictly time and frequency synchronized. To reduce the sideband leakage of the OFDM system, several techniques are proposed: FBMC (Filter-Bank Multi-Carrier, Filter Bank Multi-Carrier), UFMC (Universal Filtered Multi-Carrier, full-Filtered Multi-Carrier), GFDM (Generalized Frequency Division multiplex), and the like. Among them, UFMC is also called f-OFDM (filtered OFDM, filtered orthogonal frequency division multiplexing).

The UFMC filters each subband based on the OFDM signal, i.e. the same filter within the same subband (within the resources of the same user equipment). The UFMC technology filters the sub-bands, thereby greatly reducing the side-band leakage, greatly reducing the interference power between the sub-bands, and flexibly configuring different parameters for different sub-bands to better adapt to the service and channel requirements. This feature of UFMC is particularly suitable for the situation where services with different requirements and features coexist in the future wireless communication system.

The UFMC signals, as generally discussed in the industry, are CP (cyclic Prefix) free. When there is multipath delay of channel, there is ISI (inter-symbol interference), and if the multipath delay of channel is small, the interference can be ignored; if the channel multipath delay is large and the interference is not negligible, the technique of UFMC for ISI cancellation needs to be considered. The common technique for eliminating ISI is to add CP, and the UFMC can also adopt the method for adding CP to resist the influence of channel multipath delay and propagation delay, thereby eliminating ISI. However, when different user equipments use CPs with different lengths for different channel multipath delays and propagation delays, the symbols of the user equipments are not synchronized, as shown in fig. 1. When these ues form MU-MIMO (Multi-User Multiple-Input Multiple-Output), or are located in the same sub-band (possibly on different sub-carriers) of the UFMC, they may interfere with each other. If each user equipment adopts the same CP length, each user needs to set the CP length according to the maximum channel multipath delay and the propagation delay, thus wasting the system resource and not maximizing the system efficiency.

Disclosure of Invention

The invention provides a method and a device for generating a multi-carrier signal, which can resist the influence caused by channel multi-path delay and propagation delay and eliminate ISI.

In order to solve the above problems, the following technical solutions are adopted.

A method of generating a multi-carrier signal, comprising:

zero adding is carried out on one or more sections of single carrier signals, and signal transformation is carried out to obtain one or more transform domain signal sections;

mapping the one or more transform domain signal segments to resource positions of one or more subbands to obtain one or more subband signals;

respectively carrying out multi-carrier modulation and filtering on the one or more sub-band signals;

and superposing the multi-carrier modulated and filtered sub-band signals.

Optionally, the zero padding for one or more segments of the single-carrier signal further includes:

dividing the single carrier signal into one or more segments;

the respectively zero-filling one or more segments of single-carrier signals comprises:

and zero adding is respectively carried out on each segment of single carrier signal obtained by segmentation.

Optionally, the position where zero is added to a segment of the single-carrier signal is any one or any several of the following positions of the segment of the single-carrier signal: front, middle, back.

Optionally, when there are multiple segments of single carrier signals, the number of zero added to each segment of single carrier signal is the same or different; when zero adding is carried out at a plurality of positions in a single-carrier signal, the zero adding numbers of different positions are the same or different; the number of the zero padding of the single carrier signal of different user equipment is the same or different.

Optionally, the mapping one or more transform domain signal segments onto resource locations of one or more subbands includes:

and mapping each transform domain signal segment to the resource position of one corresponding subband respectively according to a one-to-one corresponding mode.

and dividing each transform domain signal segment into one or more segments of transform domain signals, and mapping each segment of the divided transform domain signals to the resource position of one corresponding subband in a one-to-one corresponding mode.

and combining each transform domain signal segment, then dividing into one or more segments of transform domain signals, and respectively mapping each divided segment of transform domain signals to the resource position of a corresponding subband according to a one-to-one corresponding mode.

Optionally, the separately multi-carrier modulating and filtering the one or more subband signals includes:

performing inverse signal transformation on the one or more sub-band signals respectively;

respectively carrying out middle processing on one or more sub-band signals obtained after inverse transformation; the middle treatment comprises any one or several of the following operations: multiplying by a predetermined complex vector, adding a cyclic prefix or suffix;

and respectively filtering each sub-band signal after the middle part processing.

Optionally, the middle processing refers to a vector multiplied by [1,1, … 1 ].

Optionally, before the superimposing the multi-carrier modulated and filtered subband signal, the method further includes:

performing first back-end processing on the sub-band signals subjected to multi-carrier modulation and filtering;

the first back-end processing comprises any one or any few of the following operations: multiply by a predetermined complex vector, add a cyclic prefix or suffix.

Optionally, the superimposing the multi-carrier modulated and filtered subband signal further includes:

carrying out second back-end processing on the sub-band signals subjected to multi-carrier modulation and filtering;

the second back-end processing comprises any one or any few of the following operations: multiply by a predetermined complex vector, add a cyclic prefix or suffix.

An apparatus for generating a multicarrier signal, comprising:

the front-end processing module is used for zero adding to one or more sections of single carrier signals and carrying out signal transformation to obtain one or more transform domain signal sections;

a resource mapping module, configured to map the one or more transform domain signal segments to resource locations of one or more subbands to obtain one or more subband signals;

the modulation filtering module is used for respectively carrying out multi-carrier modulation and filtering on the one or more sub-band signals;

and the back-end processing module is used for superposing the sub-band signals after multi-carrier modulation and filtering.

Optionally, the method further comprises:

the signal segmentation module is used for dividing the single carrier signal into one or more sections;

the zero padding of one or more segments of single carrier signals by the front-end processing module refers to:

and the front-end processing module respectively adds zero to each segment of single-carrier signals obtained by segmentation.

Optionally, the position where the front-end processing module performs zero padding on a segment of single-carrier signal is any one or any several of the following positions of the segment of single-carrier signal: front, middle, back.

Optionally, when there are multiple segments of single carrier signals, the number of zeros added to each segment of single carrier signals by the front-end processing module is the same or different; when zero adding is carried out at a plurality of positions in a single-carrier signal, the number of zero adding at different positions is the same or different; the number of zero-added to the single carrier signal of different user equipment is the same or different.

Optionally, the mapping, by the resource mapping module, one or more transform domain signal segments onto resource positions of one or more subbands refers to:

and the resource mapping module maps each transform domain signal segment to the resource position of one corresponding subband respectively in a one-to-one corresponding mode.

and the resource mapping module divides each transform domain signal segment into one or more segments of transform domain signals respectively, and maps each divided segment of transform domain signals to the resource position of one corresponding subband respectively according to a one-to-one corresponding mode.

and the resource mapping module combines each transform domain signal segment firstly and then divides the combined transform domain signal segment into one or more segments of transform domain signals, and maps each segment of the divided transform domain signals to the resource position of one corresponding subband respectively according to a one-to-one corresponding mode.

Optionally, the modulation filtering module includes:

an inverse transform unit for performing signal inverse transform on the one or more subband signals, respectively;

the middle processing unit is used for respectively carrying out middle processing on one or more sub-band signals obtained after inverse transformation; the middle treatment comprises any one or several of the following operations: multiplying by a predetermined complex vector, adding a cyclic prefix or suffix;

and the filtering unit is used for respectively filtering each sub-band signal after the middle part processing.

Optionally, the back-end processing module is further configured to perform a first back-end processing on the multi-carrier modulated and filtered subband signal before the multi-carrier modulated and filtered subband signal is superimposed;

Optionally, the back-end processing module is further configured to perform second back-end processing on the sub-band signals after the multi-carrier modulation and the filtering are superimposed;

The embodiment of the invention provides an improved method and a device for generating a multi-carrier signal, which can resist the influence caused by channel multipath delay and propagation delay, eliminate ISI (inter-symbol interference), and flexibly set zero-added numbers (such as different zero-added numbers or different proportions with the length of original data) aiming at the channel environments of different user equipment; and the user equipment has no interference with each other, thereby saving system resources.

Additional features and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. The objectives and other advantages of the invention will be realized and attained by the structure particularly pointed out in the written description and claims hereof as well as the appended drawings.

Drawings

The accompanying drawings are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the example serve to explain the principles of the invention and not to limit the invention.

Fig. 1 is a schematic diagram illustrating different length CPs used by different ues in the prior art;

fig. 2 is a flowchart illustrating a method for generating a multi-carrier signal according to a first embodiment;

fig. 3 is a flowchart illustrating a multi-carrier signal generation process according to an example of the first embodiment;

fig. 4 is a schematic diagram of a multicarrier signal generating apparatus according to a second embodiment;

fig. 5 is a flowchart of multicarrier signal generation in example 1;

FIG. 6 is a diagram of a first implementation of the modulation filter module of example 1;

FIG. 7 is a diagram of a second implementation of the modulation filter module of example 1;

FIG. 8 is a schematic diagram of a third implementation of the modulation filtering module of example 1;

FIG. 9 is a schematic diagram of a fourth implementation of the modulation filter module of example 1;

fig. 10 is a flowchart of multicarrier signal generation in example 2;

fig. 11 is a flowchart of multicarrier signal generation in example 3.

Detailed Description

The technical solution of the present invention will be described in more detail with reference to the accompanying drawings and examples.

It should be noted that, if not conflicting, the embodiments of the present invention and the features of the embodiments may be combined with each other within the scope of protection of the present invention. Additionally, while a logical order is shown in the flow diagrams, in some cases, the steps shown or described may be performed in an order different than here.

In an embodiment, as shown in fig. 2, a method for generating a multicarrier signal includes S120 to S150:

and S120, zero adding is carried out on one or more sections of single-carrier signals, and signal transformation is carried out to obtain one or more transformation domain signal sections.

Optionally, step S120 may further include:

and S110, dividing the single carrier signal into one or more sections.

Accordingly, nulling one or more segments of the single carrier signal may comprise: and zero adding is respectively carried out on each segment of single carrier signal obtained by segmentation.

If step S110 is not performed, zero padding is directly performed on the original single-carrier signal as a segment in step S120.

In this alternative, in step S110, the single-carrier signal segment may have various forms.

In this alternative, the length of each segment of the single-carrier signal obtained after the segmentation may be the same or different.

In this alternative, in step S110, a single carrier signal of any length of one user equipment may be divided into one or more single carrier signals.

Optionally, in step S120, the position where zero padding is performed on the segment of single-carrier signal may be any one or several of the following positions of the segment of single-carrier signal: front, middle, back. The position of the front part means zero padding is carried out before the first bit of the single carrier signal of the section; the position of the rear part means zero padding is carried out after the last bit of the single carrier signal of the section; the position is the middle part, which means that zero padding is carried out on any bit or any few bits from the first bit to the last bit of the single-carrier signal of the section. Hereinafter, for convenience of description, the zero-adding is generally referred to as signal zero-adding regardless of the position.

Optionally, the signal transformation in step S120 may be in various ways, including but not limited to discrete fourier transform or fast fourier transform, and accordingly, the transform domain may be, but not limited to, a frequency domain.

Optionally, in step S120, when there are multiple segments of single-carrier signals, the number of zeros added to each segment of single-carrier signal (i.e., several zeros are added) may be the same or different; when zero adding is carried out at a plurality of positions in a single-carrier signal, the number of zero adding at different positions can be the same or different; the number of the single carrier signal zero padding of different user equipments may be the same or different.

S130, mapping the one or more transform domain signal segments to resource positions of one or more sub-bands to obtain one or more sub-band signals.

Mapping the one or more transform domain signal segments onto resource locations of one or more subbands in step S130 includes, but is not limited to, the following optional implementations:

the first method is as follows: and mapping each transform domain signal segment obtained in step S120 to the resource position of a corresponding subband in a one-to-one correspondence manner.

The second method comprises the following steps: and dividing each transform domain signal segment obtained in step S120 into one or more segments of transform domain signals, and mapping each segment of the divided transform domain signals to the resource position of a corresponding subband in a one-to-one correspondence manner.

The third method comprises the following steps: each transform domain signal segment obtained in step S120 is first combined and then divided into one or more transform domain signals, and each divided transform domain signal segment is mapped to a resource location of a corresponding subband in a one-to-one correspondence manner.

And S140, respectively carrying out multi-carrier modulation and filtering on the one or more sub-band signals.

In step S140, the purpose of multicarrier modulation and filtering is to output a multicarrier signal, and the multicarrier signal includes one or more subband signals with sideband leakage suppression.

There are many alternative implementations of step S140, and four implementations of step S140 are given in example 1, see the description in example 1.

Optionally, step S140 includes three substeps:

and a substep S141 of performing inverse signal transformation on the one or more subband signals, respectively.

In sub-step S141, the inverse signal transform may be performed in various manners, including but not limited to an inverse discrete fourier transform or an inverse fast fourier transform.

And a substep S142 of performing middle processing on the one or more subband signals obtained in the substep S110 respectively.

In the sub-step S142, the purpose of the middle processing is to reduce a peak-to-average ratio of the final time domain signal, enhance the capability of the final time domain signal against inter-symbol interference or frequency deviation, reduce energy consumption of the final time domain signal, provide a copy signal for a subsequent process, and the like.

In the sub-step S142, the middle processing may include, but is not limited to, any one or several of the following operations: multiply by a predetermined complex vector, add a cyclic prefix or suffix, and so on.

In other alternatives, the substep S142 may not be performed, and the substep S143 may be directly performed, which corresponds to not performing the operation in the substep S142, and corresponds to the vector multiplied by [1,1, … 1] being processed in the middle.

And a substep S143 of filtering each subband signal obtained in the substep S142.

In the sub-step S143, the filtering may be performed in the time domain, and the time domain signal is filtered; equivalent filtering may also be performed in the transform domain. The transform domain includes, but is not limited to, the frequency domain.

And S150, superposing the sub-band signals subjected to multi-carrier modulation and filtering.

Optionally, in step S150, before the step of superimposing the multi-carrier modulated and filtered subband signal, the method may further include: performing first back-end processing on the sub-band signals subjected to multi-carrier modulation and filtering;

the purpose of the first back-end processing is to reduce the peak-to-average ratio of the final time domain signal, enhance the capability of the final time domain signal to resist intersymbol interference or frequency deviation, reduce the energy consumption of the final time domain signal, and the like.

The first back-end processing may include, but is not limited to, any one or any few of the following: multiply by a predetermined complex vector, add a cyclic prefix or suffix, and so on.

Optionally, before the step S150 of superposing the multi-carrier modulated and filtered subband signal, the method may further include: and carrying out second back-end processing on the sub-band signals subjected to multi-carrier modulation and filtering.

The purpose of the second back-end processing is to reduce the peak-to-average ratio of the final time domain signal, enhance the capability of the final time domain signal against intersymbol interference or frequency deviation, reduce the energy consumption of the final time domain signal, and the like.

The second back-end processing may include, but is not limited to, any one or any few of the following: multiply by a predetermined complex vector, add a cyclic prefix or suffix, and so on.

In step S150, the superimposition may be performed in the time domain or in the transform domain. The transform domain includes, but is not limited to, the frequency domain.

In step S150, both the first and second backend processes may be performed, or only one of them may be performed, or neither of them may be performed.

In steps S140 and S150, the predetermined complex vector/cyclic prefix/cyclic suffix in the middle processing, the first back-end processing, and the second back-end processing may be the same or different.

In an example of this embodiment, a flow of generating a multi-carrier signal is as shown in fig. 3, an input single-carrier signal S0 is segmented to obtain a single-carrier signal S1, a segment of the single-carrier signal in fig. 3 is represented as a set of arrows, where each arrow represents a signal of one sampling point.

Carrying out zero padding and signal transformation on each single carrier signal segment to obtain a change domain signal segment S2; the zero added positions in this example are front and rear, i.e., zero added before the first sample (i.e., the first bit) and after the last sample (i.e., the last bit) in a segment of the single carrier signal.

Performing signal combination, segmentation and resource mapping on the plurality of change domain signal segments S2 after signal transformation; in this example, it is assumed that the subband signals are divided into M segments, and the M segments of the variable domain signals are respectively mapped to resource positions of M subbands according to a one-to-one correspondence relationship, so as to obtain M subband signals S3, including: a sub-band signal S3-1, sub-band signals S3-2, … …, and sub-band signals S3-M.

The multi-carrier modulation and filtering are performed on the subband signal S3 to obtain M modulated and filtered subband signals S4, which includes: a sub-band signal S4-1, sub-band signals S4-2, … …, and sub-band signals S4-M.

And performing back-end processing on the modulated and filtered sub-band signal S4 to obtain a signal S5 to be transmitted.

In a second embodiment, a multicarrier signal generating apparatus, as shown in fig. 4, includes:

a front-end processing module 42, configured to zero-add one or more segments of single carrier signals, perform signal transformation, and obtain one or more transform domain signal segments;

a resource mapping module 43, configured to map the one or more transform domain signal segments to resource positions of one or more subbands, so as to obtain one or more subband signals;

a modulation filtering module 44, configured to perform multicarrier modulation and filtering on the one or more subband signals respectively;

and a back-end processing module 45, configured to superimpose the multi-carrier modulated and filtered subband signals.

Optionally, the apparatus further comprises:

a signal segmentation module 41, configured to divide the single carrier signal into one or more segments;

the front-end processing module 42 zero-filling one or more segments of single carrier signals means:

the front-end processing module 42 performs zero padding on each segment of the single-carrier signal obtained by segmentation.

If the apparatus does not include the signal segmentation module 41, the front-end processing module 42 directly zero-adds the original single-carrier signal as a segment.

Optionally, when there are multiple segments of single carrier signals, the number of zeros added to each single carrier signal by the front-end processing module is the same or different; when zero adding is carried out at a plurality of positions in a single-carrier signal, the number of zero adding at different positions is the same or different; the number of zero-added to the single carrier signal of different user equipment is the same or different.

Optionally, the modulation filtering module includes:

Wherein the middle processing may refer to, but is not limited to, a vector multiplied by [1,1, … 1 ].

the second back-end processing may include, but is not limited to, any one or any few of the following: multiply by a predetermined complex vector, add a cyclic prefix or suffix.

The above embodiments are further illustrated below by 3 examples.

Example 1

The embodiment provides a signal generation method, which improves the UFMC technology, can resist the influence caused by channel multipath delay and propagation delay, eliminates ISI, flexibly adopts different parameters aiming at the channel environment of different user equipment, has no interference with each other, and saves system resources.

The specific method of the embodiment comprises the following steps 101-105:

101: single carrier signal segmentation;

101, the single-carrier signal segment can have various forms;

in 101, a single carrier signal of an arbitrary length for one user equipment can be divided into one or more segments of single carrier signals.

102: and after zero padding is respectively carried out on each segment of single carrier signal obtained by segmentation, signal transformation is carried out to obtain a plurality of transform domain signal segments.

In 102, the position where zero padding is performed on each segment of the single-carrier signal may be any one or any several of the following positions of each segment of the single-carrier signal: front, middle, back.

The signal in 102 may be transformed in a number of ways including, but not limited to, a discrete fourier transform or a fast fourier transform, and accordingly, the transform domain may be, but is not limited to, the frequency domain.

102, the number of zero-added per segment of the single carrier signal may be different; when zero adding is performed at a plurality of positions in a single-carrier signal, the number of zero adding at different positions can be different; the number of single carrier signal nulling for different user equipments may also be different.

103: and according to a one-to-one correspondence mode, mapping each transform domain signal segment obtained by 102 to the resource position of a corresponding subband respectively to form an input signal of the corresponding subband.

104: the subband signals obtained at 103 are subjected to multicarrier modulation and filtering.

At 104, the purpose of multicarrier modulation and filtering is to output a multicarrier signal and to include a plurality of subband signals subjected to sideband leakage suppression.

There are many alternative implementations of step 104, and four implementations of step 104 are given in this example, see below.

The above implementation of step 104 may also be applied to other examples, which are not described in detail later.

104 may include three substeps:

the first substep: and each sub-band signal is subjected to signal inverse transformation respectively.

In sub-step one, the inverse signal transform may be performed in various ways, including but not limited to an inverse discrete fourier transform or an inverse fast fourier transform.

And a second substep: and respectively carrying out middle processing on the plurality of sub-band signals obtained in the sub-step one.

In the sub-step two, the purpose of the middle processing is to reduce the peak-to-average ratio of the final time domain signal, enhance the capability of the final time domain signal against intersymbol interference or frequency deviation, reduce the energy consumption of the final time domain signal, provide a copy signal for the subsequent process, and the like.

In sub-step two, the middle processing may include, but is not limited to, any one or several of the following operations: multiply by a predetermined complex vector, add a cyclic prefix or suffix, and so on.

In the second substep, no operation may be performed, which corresponds to a vector multiplied by [1,1, … 1], and may be considered as a specific example of the second substep.

And a third substep: and respectively filtering the plurality of sub-band signals obtained in the sub-step two.

In the third sub-step, the filtering may be performed in the time domain, and the filtering may be performed on the time domain signal; equivalent filtering may also be performed in the transform domain. The transform domain includes, but is not limited to, the frequency domain.

105: the multi-carrier modulated and filtered multiple sub-band signals obtained at 104 are post-processed.

In 105, the back-end processing includes first back-end processing on the subband signal, superimposing the plurality of subband signals, and second back-end processing.

In 105, the purpose of the first back-end processing is to reduce a peak-to-average ratio of the final time domain signal, enhance the capability of the final time domain signal against inter-symbol interference or frequency deviation, reduce energy consumption of the final time domain signal, and the like. The first back-end processing may include, but is not limited to, the following: multiply by a predetermined complex vector, add a cyclic prefix or suffix, and so on.

In 105, the purpose of the second back-end processing is to reduce the peak-to-average ratio of the final time domain signal, enhance the capability of the final time domain signal against intersymbol interference or frequency deviation, reduce the energy consumption of the final time domain signal, and the like. The second back-end processing may include, but is not limited to, the following: multiply by a predetermined complex vector, add a cyclic prefix or suffix, and so on.

In 105, the subband signals may be superimposed in the time domain or in the transform domain. The transform domain includes, but is not limited to, the frequency domain.

The embodiment can be realized by adopting the device of the second embodiment.

The multi-carrier signal generation flow of this example is shown in fig. 5, after the input single-carrier signal S10 is segmented, a single-carrier signal S11 is obtained, in fig. 5, a segment of the single-carrier signal is represented as a set of arrows, where each arrow represents a signal of one sampling point.

Carrying out zero padding and signal transformation on each single carrier signal segment to obtain a change domain signal segment S12; the zero added positions in this example are front and rear, i.e., zero added before the first sample (i.e., the first bit) and after the last sample (i.e., the last bit) in a segment of the single carrier signal.

The plurality of signal segments S12 in the change domain after signal transformation are mapped to resource positions of M subbands according to a one-to-one correspondence, that is: combining the input signals of sub-band 1, sub-band 2, sub-band … …, and sub-band M, respectively, to obtain sub-band signal S13, comprising: a sub-band signal S13-1, sub-band signals S13-2, … …, and sub-band signals S13-M.

The multi-carrier modulation and filtering are performed on the subband signal S13 to obtain M modulated and filtered subband signals S14, which includes: modulation filtered subband signal S14-1, modulation filtered subband signals S14-2, … …, modulation filtered subband signal S14-M.

And performing back-end processing on the modulated and filtered sub-band signal S14 to obtain a signal S15 to be transmitted.

The multi-carrier modulation and filtering in 104 includes four optional implementation manners as follows:

in a first implementation manner, the inverse transform of the first sub-step in 104 is inverse discrete fourier transform, and the filtering of the third sub-step is performed by using a Band-Pass Filter (BPF).

In this implementation, the modulation filtering module is shown in fig. 6 and includes inverse discrete fourier transform units 5-1, 5-2, … …, 5-M; middle treatment units 6-1, 6-2, … …, 6-M; band pass filters 7-1, 7-2, … …, 7-M; the inverse discrete Fourier transform unit is connected with the middle processing unit in a one-to-one corresponding mode, and the middle processing unit is connected with the BPF in a one-to-one corresponding mode.

Sub-band signals S13-1, S13-2, … … and S13-M are respectively input into inverse discrete Fourier transform units 5-1, 5-2, … … and 5-M; the band pass filters 7-1, 7-2, … …, 7-M output modulation filtered subband signals S14-1, S14-2, … …, S14-M, respectively.

The difference between the second implementation and the first implementation is that the filtering in the third sub-step is implemented by using LPF (Low Pass Filter) and multiplier.

In this implementation, the modulation filtering module is shown in fig. 7 and includes inverse discrete fourier transform units 5-1, 5-2, … …, 5-M; middle treatment units 6-1, 6-2, … …, 6-M; low-pass filters 8-1, 8-2, … …, 8-M and M multipliers; the inverse discrete Fourier transform unit is connected with the middle processing unit in a one-to-one corresponding way, and the middle processing unit is connected with the LPF in a one-to-one corresponding way; LPF is connected with the multipliers in one-to-one correspondence and is respectively connected with the reference frequency f_1-1、f_1-2、……、f_1-MMultiplying; a low-pass filter and a multiplier which are connected form a filtering unit.

Sub-band signals S13-1, S13-2, … … and S13-M are respectively input into inverse discrete Fourier transform units 5-1, 5-2, … … and 5-M; the M multipliers output modulation-filtered subband signals S14-1, S14-2, … …, S14-M, respectively.

The third implementation mode is different from the second implementation mode in that the first sub-step adopts inverse fast Fourier transform, all sub-band signals adopt an IFFT unit to complete inverse transform, and a middle processing unit is adopted to complete middle processing; in the third substep, the result of the middle processing is multiplied by the reference frequency, and then sent to an LPF (Low Pass Filter), and the output of the LPF is up-sampled and then input to the multiplier.

In this implementation, the modulation filtering module is shown in fig. 8 and includes an inverse fast fourier transform unit 10-0; a middle processing unit 6-0; m first multipliers; low pass filters 8-1, 8-2, … …, 8-M; upsampling units 9-1, 9-2, … …, 9-M, and M second multipliers; the inverse fast Fourier transform unit is connected with the middle processing unit, the middle processing unit is connected with the M multipliers, and the middle processing unit and the M multipliers are respectively connected with the reference frequency f_2-1、f_2-2、……、f_2-MAfter multiplication, inputting the multiplied signal into an LPF; the LPFs are connected with the up-sampling units in a one-to-one corresponding mode; upsampling unit and second multiplierConnected in one-to-one correspondence with the reference frequency f_1-1、f_1-2、……、f_1-MMultiplying; a first multiplier, a low-pass filter, an up-sampling unit and a second multiplier which are connected form a filtering unit.

The sub-band signals S13-1, S13-2, … …, S13-M are all inputted to the inverse fast Fourier transform unit 10-0; the M second multipliers output modulation-filtered subband signals S14-1, S14-2, … …, S14-M, respectively.

The difference between the fourth implementation and the second implementation is that in the first sub-step, inverse fast fourier transform is used, and in the third sub-step, the output of LPF (Low Pass Filter) is up-sampled and then input to the multiplier.

In this implementation, the modulation filtering module is shown in fig. 9 and includes inverse fast fourier transform units 10-1, 10-2, … …, 10-M; middle treatment units 6-1, 6-2, … …, 6-M; low pass filters 8-1, 8-2, … …, 8-M; upsampling units 9-1, 9-2, … …, 9-M, and M multipliers; the inverse fast Fourier transform units are connected with the middle processing units in a one-to-one corresponding manner, and the middle processing units are connected with the LPFs in a one-to-one corresponding manner; the LPFs are connected with the up-sampling units in a one-to-one corresponding mode; the up-sampling units are correspondingly connected with the multipliers one by one and respectively connected with the reference frequency f_1-1、f_1-2、……、f_1-MMultiplying; a low-pass filter, an up-sampling unit and a multiplier which are connected form a filtering unit.

Sub-band signals S13-1, S13-2, … … and S13-M are respectively input into inverse fast Fourier transform units 10-1, 10-2, … … and 10-M; the M multipliers output modulation-filtered subband signals S14-1, S14-2, … …, S14-M, respectively.

Example 2

The embodiment provides a method for generating a multi-carrier signal, which improves the UFMC technology, can resist the influence caused by channel multipath delay and propagation delay, eliminates ISI, flexibly adopts different parameters aiming at the channel environment of different user equipment, has no interference with each other, and saves system resources.

The steps of the embodiment comprise the following steps 201-205:

201: single carrier signal segmentation;

in 201, the single-carrier signal segment can have various forms;

in 201, a single carrier signal of an arbitrary length for one user equipment can be divided into one or more segments of single carrier signals.

202: and after zero padding is respectively carried out on each segment of single carrier signal obtained by segmentation, signal transformation is carried out to obtain a plurality of transform domain signal segments.

In 202, the position where zero padding is performed on a segment of single-carrier signal may be any one or any several of the following positions of the segment of single-carrier signal: front, middle, back.

The signal in 202 may be transformed in a number of ways including, but not limited to, a discrete fourier transform or a fast fourier transform, and accordingly, the transform domain may be, but is not limited to, the frequency domain.

202, the number of zero-added per segment of single carrier signal may be different; when zero adding is performed at a plurality of positions in a single-carrier signal, the number of zero adding at different positions can be different; the number of single carrier signal nulling for different user equipments may also be different.

203: dividing each transform domain signal segment obtained in step 202 into one or more segments of transform domain signals, and mapping each segment of the divided transform domain signals to the resource position of a corresponding subband in a one-to-one correspondence manner.

204: the plurality of subband signals obtained at 203 are subjected to multicarrier modulation and filtering, respectively.

At 204, the purpose of multicarrier modulation and filtering is to output a multicarrier signal and to include a plurality of subband signals subjected to sideband leakage suppression. There are many implementations of step 204, and several implementations of step 204 are given in example 1.

204 may include three substeps:

205: the multi-carrier modulated and filtered multiple sub-band signals obtained at 204 are post-processed.

In 205, the back-end processing includes a first back-end processing on the subband signal, the superposition of the plurality of subband signals, and a second back-end processing.

205, the purpose of the first back-end processing is to reduce a peak-to-average ratio of the final time domain signal, enhance the capability of the final time domain signal against inter-symbol interference or frequency deviation, reduce energy consumption of the final time domain signal, and the like. The first back-end processing may include, but is not limited to, the following: multiply by a predetermined complex vector, add a cyclic prefix or suffix, and so on.

205, the purpose of the second back-end processing is to reduce the peak-to-average ratio of the final time domain signal, enhance the capability of the final time domain signal to resist inter-symbol interference or frequency deviation, reduce the energy consumption of the final time domain signal, and so on. The second back-end processing may include, but is not limited to, the following: multiply by a predetermined complex vector, add a cyclic prefix or suffix, and so on.

205, the superposition of the subband signals may be performed in the time domain or in the transform domain. The transform domain includes, but is not limited to, the frequency domain.

The embodiment can be realized by adopting the device of the second embodiment.

The flow of generating a multicarrier signal in this example is as shown in fig. 10, and after an input single-carrier signal S20 is segmented, a single-carrier signal S21 is obtained, and in fig. 10, the case of segmenting into one single-carrier signal is shown, and when segmenting into multiple segments, the processing flow of each segment of single-carrier signal is the same as that in fig. 10. One single-carrier signal is represented in fig. 10 as a set of arrows, where each arrow represents a signal of one sampling point.

Carrying out zero padding and signal transformation on each single carrier signal segment to obtain a change domain signal segment S22; the zero added positions in this example are front and rear, i.e., zero added before the first sample (i.e., the first bit) and after the last sample (i.e., the last bit) in a segment of the single carrier signal.

The plurality of signal segments S22 in the change domain after signal transformation are mapped to resource positions of M subbands according to a one-to-one correspondence, that is: combining the input signals of sub-band 1, sub-band 2, sub-band … …, and sub-band M, respectively, to obtain sub-band signal S23, comprising: a sub-band signal S23-1, sub-band signals S23-2, … …, and sub-band signals S23-M.

The multi-carrier modulation and filtering are performed on the subband signal S23 to obtain M modulated and filtered subband signals S24, which includes: modulation filtered subband signal S24-1, modulation filtered subband signals S24-2, … …, modulation filtered subband signal S24-M.

And performing back-end processing on the modulated and filtered sub-band signal S24 to obtain a signal S25 to be transmitted.

Example 3

The steps of the embodiment comprise the following steps 301-305:

301: single carrier signal segmentation;

301, the single-carrier signal segment may have multiple forms;

in 301, a single carrier signal of an arbitrary length for one user equipment may be divided into one or more pieces of single carrier signals.

302: and after zero padding is respectively carried out on each segment of single carrier signal obtained by segmentation, signal transformation is carried out to obtain a plurality of transform domain signal segments.

In 302, the position where zero padding is performed on a segment of single-carrier signal may be any one or any several of the following positions of the segment of single-carrier signal: front, middle, back.

The signal in 302 may be transformed in a number of ways including, but not limited to, a discrete fourier transform or a fast fourier transform, and accordingly, the transform domain may be, but is not limited to, the frequency domain.

In 302, the number of zero-added per segment of the single carrier signal may be different; when zero adding is performed at a plurality of positions in a single-carrier signal, the number of zero adding at different positions can be different; the number of single carrier signal nulling for different user equipments may also be different.

303: each transform domain signal segment obtained in step 302 is first combined and then divided into one or more segments of transform domain signals, and each segment of transform domain signals is mapped to the resource position of a corresponding subband in a one-to-one correspondence manner.

304: the plurality of subband signals obtained at 303 are subjected to multicarrier modulation and filtering, respectively.

At 304, the purpose of multicarrier modulation and filtering is to output a multicarrier signal and to include a plurality of subband signals subjected to sideband leakage suppression. There are many implementations of step 304, and several implementations of step 204 are given in example 1.

304 may include three substeps:

305: the multi-carrier modulated and filtered plurality of subband signals resulting from 304 are post-processed.

In 305, the back-end processing includes a first back-end processing on the subband signal, the superposition of the plurality of subband signals, and a second back-end processing.

In 305, the purpose of the first back-end processing is to reduce the peak-to-average ratio of the final time domain signal, enhance the capability of the final time domain signal to resist inter-symbol interference or frequency deviation, reduce the energy consumption of the final time domain signal, and so on. The first back-end processing may include, but is not limited to, the following: multiply by a predetermined complex vector, add a cyclic prefix or suffix, and so on.

In 305, the purpose of the second back-end processing is to reduce the peak-to-average ratio of the final time domain signal, enhance the capability of the final time domain signal to resist inter-symbol interference or frequency deviation, reduce the energy consumption of the final time domain signal, and so on. The second back-end processing may include, but is not limited to, the following: multiply by a predetermined complex vector, add a cyclic prefix or suffix, and so on.

In 305, the subband signals may be superimposed in the time domain or in the transform domain. The transform domain includes, but is not limited to, the frequency domain. The embodiment can be realized by adopting the device of the second embodiment.

The flow of generating the multi-carrier signal in this example is shown in fig. 11, after the input single-carrier signal S30 is segmented, a single-carrier signal S31 is obtained, in fig. 11, a segment of the single-carrier signal is represented as a set of arrows, where each arrow represents a signal of one sampling point.

Carrying out zero padding and signal transformation on each single carrier signal segment to obtain a change domain signal segment S32; the zero added positions in this example are front and rear, i.e., zero added before the first sample (i.e., the first bit) and after the last sample (i.e., the last bit) in a segment of the single carrier signal.

Combining a plurality of signal segments S32 of the changed domain after signal transformation, then dividing into M segments, and respectively mapping onto resource positions of M sub-bands, namely: combining the input signals of sub-band 1, sub-band … … and sub-band M to obtain sub-band signal S33, comprising: sub-band signals S33-1, … …, sub-band signal S33-M. In this example, every N (N is a positive integer greater than 1) change field signal segments S32 are combined and divided into one segment, but the implementation is not limited to this method, and may be any combination or segmentation method.

The multi-carrier modulation and filtering are performed on the subband signal S33 to obtain M modulated and filtered subband signals S34, which includes: the filtered subband signals S34-1, … … are modulated, the filtered subband signal S34-M is modulated.

And performing back-end processing on the modulated and filtered sub-band signal S34 to obtain a signal S35 to be transmitted.

It will be understood by those skilled in the art that all or part of the steps of the above methods may be implemented by instructing the relevant hardware through a program, and the program may be stored in a computer readable storage medium, such as a read-only memory, a magnetic or optical disk, and the like. Alternatively, all or part of the steps of the above embodiments may be implemented using one or more integrated circuits. Accordingly, each module/unit in the above embodiments may be implemented in the form of hardware, and may also be implemented in the form of a software functional module. The present invention is not limited to any specific form of combination of hardware and software.

Although the embodiments of the present invention have been described above, the above description is only for the convenience of understanding the present invention, and is not intended to limit the present invention. It will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.

Claims

1. A method of generating a multi-carrier signal, comprising:

zero adding is carried out on multiple sections of single carrier signals, and signal transformation is carried out to obtain multiple transform domain signal sections;

mapping the plurality of transform domain signal segments to resource positions of a plurality of sub-bands to obtain a plurality of sub-band signals;

respectively carrying out multi-carrier modulation and filtering on the plurality of sub-band signals;

superposing the sub-band signals subjected to multi-carrier modulation and filtering;

when multiple sections of single-carrier signals exist, the zero adding number of each section of single-carrier signals is different; when zero adding is carried out at a plurality of positions in a single-carrier signal, the zero adding numbers of different positions are the same or different; the number of zero padding of single carrier signals of different user equipment is the same or different;

the zero-padding position of a segment of single-carrier signal is any one or several of the following positions of the segment of single-carrier signal: a front portion, a middle portion, a rear portion;

when there are multiple sections of single carrier signals, the length of each section of single carrier signal is different.

2. The method of claim 1, wherein said nulling the multi-segment single-carrier signal further comprises:

dividing the single carrier signal into a plurality of sections;

the zero padding for the multi-segment single carrier signals respectively comprises the following steps:

3. The method of claim 1, wherein said mapping the plurality of transform domain signal segments onto resource locations of the plurality of subbands comprises:

4. The method of claim 1, wherein said mapping the plurality of transform domain signal segments onto resource locations of the plurality of subbands comprises:

5. The method of claim 1, wherein said mapping the plurality of transform domain signal segments onto resource locations of the plurality of subbands comprises:

and combining each transform domain signal segment, then dividing into a plurality of segments of transform domain signals, and respectively mapping each segment of the divided transform domain signals to the resource position of one corresponding subband according to a one-to-one corresponding mode.

6. The method of claim 1, wherein the separately multi-carrier modulating and filtering the plurality of subband signals comprises:

performing inverse signal transformation on the plurality of sub-band signals respectively;

respectively carrying out middle processing on a plurality of sub-band signals obtained after inverse transformation; the middle treatment comprises any one or several of the following operations: multiplying by a predetermined complex vector, adding a cyclic prefix or suffix;

7. The method of claim 6, wherein:

the middle processing refers to a vector multiplied by [1,1, … 1 ].

8. The method of claim 1, wherein the pre-superimposing the multi-carrier modulated and filtered subband signals further comprises:

9. The method of claim 1, wherein the superimposing the multi-carrier modulated and filtered subband signals further comprises:

10. An apparatus for generating a multicarrier signal, comprising:

the front-end processing module is used for zero adding to the multi-segment single carrier signal, and performing signal transformation to obtain a plurality of transform domain signal segments;

a resource mapping module, configured to map the multiple transform domain signal segments to resource positions of multiple subbands to obtain multiple subband signals;

the modulation filtering module is used for respectively carrying out multi-carrier modulation and filtering on the plurality of sub-band signals;

the back-end processing module is used for superposing the sub-band signals subjected to multi-carrier modulation and filtering;

when multiple segments of single-carrier signals exist, the front-end processing module has different zero adding numbers for each segment of single-carrier signals; when zero adding is carried out at a plurality of positions in a single-carrier signal, the number of zero adding at different positions is the same or different; the number of zero-added to the single carrier signals of different user equipment is the same or different;

the zero padding position of the front-end processing module for a segment of single-carrier signal is any one or any several of the following positions of the segment of single-carrier signal: a front portion, a middle portion, a rear portion;

11. The apparatus of claim 10, further comprising:

the signal segmentation module is used for dividing the single carrier signal into a plurality of segments;

the zero padding of the multi-segment single carrier signal by the front-end processing module is as follows:

12. The apparatus of claim 10, wherein the resource mapping module maps the plurality of transform domain signal segments onto resource locations of a plurality of subbands is to:

13. The apparatus of claim 10, wherein the resource mapping module maps the plurality of transform domain signal segments onto resource locations of a plurality of subbands is to:

14. The apparatus of claim 10, wherein the resource mapping module maps the plurality of transform domain signal segments onto resource locations of a plurality of subbands is to:

and the resource mapping module combines each transform domain signal segment firstly and then divides the transform domain signal segment into a plurality of segments of transform domain signals, and maps each segment of the divided transform domain signals to the resource position of one corresponding subband respectively according to a one-to-one corresponding mode.

15. The apparatus of claim 10, wherein the modulation filtering module comprises:

an inverse transform unit for performing signal inverse transform on the plurality of subband signals, respectively;

the middle processing unit is used for respectively carrying out middle processing on a plurality of sub-band signals obtained after inverse transformation; the middle treatment comprises any one or several of the following operations: multiplying by a predetermined complex vector, adding a cyclic prefix or suffix;

16. The apparatus of claim 15, wherein:

the middle processing refers to a vector multiplied by [1,1, … 1 ].

17. The apparatus of claim 10, wherein:

the back-end processing module is further configured to perform first back-end processing on the sub-band signals after multi-carrier modulation and filtering before superimposing the sub-band signals after multi-carrier modulation and filtering;

18. The apparatus of claim 10, wherein:

the back-end processing module is further configured to perform second back-end processing on the sub-band signals subjected to multi-carrier modulation and filtering after the sub-band signals subjected to multi-carrier modulation and filtering are superimposed;