WO2015035604A1

WO2015035604A1 - Transmission method, user equipment, and base station for d2d communication

Info

Publication number: WO2015035604A1
Application number: PCT/CN2013/083461
Authority: WO
Inventors: 张磊; 王轶; 周华
Original assignee: 富士通株式会社
Priority date: 2013-09-13
Filing date: 2013-09-13
Publication date: 2015-03-19
Also published as: CN105325036A; CN105325036B

Abstract

Provided in embodiments of the present invention are a transmission method, user equipment, and base station for D2D communication. The user equipment employs an OFDM signal modulation scheme for an uplink time-frequency resource or employs an SC-FDM signal modulation scheme for a downlink time-frequency resource to conduct D2D communication. The method comprises: a user equipment either aligns a subcarrier center of a D2D communication signal that employs an OFDM signal modulation scheme with a subcarrier center of an uplink time-frequency resource signal or aligns a subcarrier center of a D2D communication signal that employs an SC-FDM signal modulation scheme with a subcarrier center of a downlink time-frequency resource signal. The embodiments of the present invention allow a signal of D2D communication to remain orthogonal with a signal of an uplink time-frequency resource and prevents mutual aliasing that affects the quality of communication.

Description

Transmission method, user equipment and base station of D2D communication

The present invention relates to the field of communications, and in particular, to a method for transmitting D2D communication, a user equipment, and a base station. Background technique

Currently, device-to-device (D2D) communication is an important topic discussed in the LTE standard process. In the LTE standard, an Orthogonal Frequency Division Multiplexing (OFDM) signal modulation method is currently used in a downlink in which a base station communicates with a User Equipment (UE); The impact of the Peak-to-Average Power Ratio (PAPR) on user equipment is currently based on Single-Carrier Frequcency Division Multiplexing (SC-FDM) signal modulation.

In the OFDM OFDM signal modulation scheme and the SC-FDM signal modulation scheme, the most common subcarrier spacing is 15 kHz, but the mapping method of the subcarriers in the frequency domain is different in the two modulation schemes. 1 is a schematic diagram of a mapping manner of an existing uplink subcarrier, and FIG. 2 is a schematic diagram of a mapping manner of an existing downlink subcarrier; FIG. 1 shows an uplink SC-FDM signal modulation scheme and a downlink OFDM signal modulation, respectively. the way.

As shown in Figures 1 and 2, the subcarrier mapping modes of the uplink signal and the downlink signal are different, and the subcarrier center positions are different by 7.5 kHz, that is, half of the subcarriers. Further, in the OFDM signal modulation scheme, there may be zero subcarriers.

In the current discussion of the LTE standard conference, it is considered that if the D2D user equipment needs to occupy the common time-frequency resources of one cell for D2D communication, then the uplink frequency band of the occupied cell is more reasonable, and thus the interference generated by the D2D communication only affects. The reception on the base station side does not affect the reception on the UE side. Compared with the UE side, the signal processing capability of the base station side is stronger, and accordingly, the anti-interference capability is also stronger.

However, considering that the uplink time-frequency resources of the cell are limited in some cases, for example, the uplink and downlink frame structures in the Time Division Duplex (TDD) mode may include only one or two uplink subframes, It is also possible to use the downlink time-frequency resources of the cell for D2D communication in the future.

For the D2D communication between the UEs, whether the uplink time-frequency resources or the downlink time-frequency resources of the cell are used, the signals between the two UEs may adopt an OFDM modulation method or an SC-FDM modulation method. Taking the uplink time-frequency resource for communication as an example, the SC-FDM signal modulation method can reuse the UE side transmission device. Set and guarantee a lower PAPR level; OFDM modulation can reuse the receiver module on the UE side, reduce the pilot density, and provide a more flexible resource scheduling mode.

It should be noted that the above description of the technical background is only for the purpose of facilitating the clear and complete description of the technical solutions of the present invention, and is convenient for understanding by those skilled in the art. The above technical solutions are not considered to be well known to those skilled in the art simply because these solutions are set forth in the background section of the present invention. Summary of the invention

However, the inventor has found that: if the uplink time-frequency resource adopts the existing OFDM modulation mode of LTE or the downlink time-frequency resource adopts the existing LTE SC-FDM modulation mode for D2D communication, the D2D communication signal and the ordinary uplink Or the downlink signals may overlap each other, which in turn affects the communication quality. The overlap caused by this lack of orthogonality is mainly caused by the fact that the existing LTE OFDM modulation method and the SC-FDM modulation method deviate from each other by half a subcarrier in the subcarrier mapping.

Embodiments of the present invention provide a transmission method, a user equipment, and a base station of D2D communication. The purpose is to solve the problem that the above D2D communication signal and ordinary uplink or downlink signals may overlap with each other to affect the communication quality.

According to an aspect of the embodiments of the present invention, a method for transmitting D2D communication is provided. The user equipment adopts an OFDM signal modulation mode on an uplink time-frequency resource or a SC-FDM signal modulation mode on a downlink time-frequency resource to perform D2D communication. The method includes:

The user equipment aligns a subcarrier center of the D2D communication signal using the OFDM signal modulation mode with a subcarrier center of the uplink time frequency resource signal; or

The user equipment aligns the subcarrier center of the D2D communication signal in the SC-FDM signal modulation mode with the subcarrier center of the downlink time-frequency resource signal.

According to another aspect of the embodiments of the present invention, a method for transmitting D2D communication is provided. The user equipment adopts an OFDM signal modulation mode on an uplink time-frequency resource, or uses an SC-FDM signal modulation mode to perform D2D communication on a downlink time-frequency resource. , the method includes:

The user equipment vacates one or more subcarriers in a D2D communication signal using an OFDM signal modulation mode; or

The user equipment vacates one or more subcarriers in a D2D communication signal adopting an SC-FDM signal modulation mode. According to another aspect of the embodiments of the present invention, a method for transmitting D2D communication is provided, where the method includes: a base station scheduling a user equipment for D2D communication on a resource that is not adjacent to a zero subframe.

According to another aspect of the present invention, a user equipment is provided, where an OFDM signal modulation mode is adopted on an uplink time-frequency resource, or an SC-FDM signal modulation mode is used to perform D2D communication on a downlink time-frequency resource, where the user equipment is used. Includes:

The first mapping unit aligns the subcarrier center of the D2D communication signal adopting the OFDM signal modulation mode with the subcarrier center of the uplink time-frequency resource signal; or, the subcarrier center of the D2D communication signal adopting the SC-FDM signal modulation mode The subcarrier center of the downlink time-frequency resource signal is aligned.

The second mapping unit vacates one or more subcarriers in the D2D communication signal adopting the OFDM signal modulation mode; or, the one or more subcarriers are hollow in the D2D communication signal adopting the SC-FDM signal modulation mode.

According to another aspect of the embodiments of the present invention, a base station is provided, where the base station includes:

The scheduling unit schedules the user equipment for D2D communication on resources that are not adjacent to the zero subframe.

According to another aspect of an embodiment of the present invention, there is provided a communication system comprising the user equipment as described above, and a base station as described above.

According to still another aspect of an embodiment of the present invention, a computer readable program is provided, wherein when the program is executed in a base station, the program causes a computer to perform a transmission method of D2D communication as described above in the base station.

According to still another aspect of an embodiment of the present invention, a storage medium storing a computer readable program, wherein the computer readable program causes a computer to perform a transmission method of D2D communication as described above in a base station.

According to still another aspect of an embodiment of the present invention, a computer readable program is provided, wherein when the program is executed in a user equipment, the program causes a computer to perform transmission of D2D communication as described above in the user equipment method.

According to still another aspect of an embodiment of the present invention, a storage medium storing a computer readable program, wherein the computer readable program causes a computer to perform transmission of D2D communication as described above in a user equipment Method.

The beneficial effects of the embodiments of the present invention are: aligning the subcarrier center of the D2D communication signal with the subcarrier center of the uplink/downlink time-frequency resource signal, so that the signal of the D2D communication and the signal of the uplink time-frequency resource are orthogonal; One or more subcarriers are hollow in the D2D communication signal to avoid maximum interference between adjacent subcarriers. Thereby, communication quality problems due to aliasing of signals can be solved or suppressed.

Specific embodiments of the present invention are disclosed in detail with reference to the following description and drawings, which illustrate the manner in which the principles of the invention may be employed. It should be understood that the embodiments of the invention are not limited in scope. The embodiments of the present invention include many variations, modifications, and equivalents within the spirit and scope of the appended claims.

Features described and/or illustrated with respect to one embodiment may be used in the same or similar manner in one or more other embodiments, in combination with, or in place of, features in other embodiments. .

It should be emphasized that the term "comprising", when used herein, refers to the presence of a feature, component, step or component, but does not exclude the presence or addition of one or more other features, components, steps or components. DRAWINGS

Many aspects of the invention can be better understood with reference to the following drawings. The components in the figures are not drawn to scale, but only to illustrate the principles of the invention. In order to facilitate the illustration and description of some parts of the invention, the corresponding parts in the drawings may be enlarged or reduced.

The elements and features described in one of the figures or one embodiment of the invention may be combined with elements and features illustrated in one or more other figures or embodiments. In the accompanying drawings, like reference numerals refer to the

1 is a schematic diagram of a mapping manner of an existing uplink subcarrier;

2 is a schematic diagram of a mapping manner of existing downlink subcarriers;

3 is a schematic flowchart of a method for transmitting D2D communication according to Embodiment 1 of the present invention;

4 is a schematic diagram of a D2D signal moving to a left half of a subframe according to Embodiment 1 of the present invention;

5 is a schematic diagram of a D2D signal moving to a right half of a subframe according to Embodiment 1 of the present invention;

6 is a schematic diagram of canceling a zero subcarrier and moving a half subframe to the left/right according to Embodiment 1 of the present invention; FIG. 7 is a diagram showing a reserved zero subcarrier and a left/right shift of a half subframe according to Embodiment 1 of the present invention; FIG. 8 is a schematic diagram of adding a zero subcarrier and moving a half subframe to the left/right according to Embodiment 1 of the present invention; FIG. 9 is a schematic diagram of moving a half subframe to the left/right according to Embodiment 1 of the present invention;

10 is a schematic diagram of adding a zero subcarrier and moving a half subframe to the left/right direction according to Embodiment 1 of the present invention; FIG. 11 is a schematic flowchart of a method for transmitting D2D communication according to Embodiment 2 of the present invention;

12 is a schematic diagram of a left idle subcarrier on the left side according to Embodiment 2 of the present invention;

13 is a schematic diagram of a null subcarrier on the right side according to Embodiment 2 of the present invention;

14 is a schematic diagram of a null subcarrier on both sides according to Embodiment 2 of the present invention;

15 is a schematic diagram of a method for transmitting D2D communication according to Embodiment 3 of the present invention;

16 is a schematic structural diagram of a user equipment according to Embodiment 4 of the present invention;

17 is a schematic structural diagram of a user equipment according to Embodiment 5 of the present invention;

18 is a schematic structural diagram of a base station according to Embodiment 6 of the present invention;

Figure 19 is a block diagram showing the configuration of a communication system according to a seventh embodiment of the present invention.

detailed description

The foregoing and other features of the invention will be apparent from the The specific embodiments of the present invention are disclosed in the specification and the drawings, which are illustrated in the embodiments of the invention The invention includes all modifications, variations and equivalents falling within the scope of the appended claims.

Example 1

The embodiment of the invention provides a method for transmitting D2D communication, which is applied to the user equipment side. The user equipment uses the OFDM signal modulation mode for D2D communication on the uplink time-frequency resources, or adopts the SC-FDM signal modulation mode for D2D communication on the downlink time-frequency resources.

FIG. 3 is a schematic flowchart of a method for transmitting D2D communication according to an embodiment of the present invention. As shown in FIG. 3, the method includes:

Step 301: The user equipment aligns a subcarrier center of the D2D communication signal that adopts the OFDM signal modulation mode with a subcarrier center of the uplink time-frequency resource signal, or uses a subcarrier center and a downlink of the D2D communication signal that adopts the SC-FDM signal modulation mode. The subcarrier center of the time-frequency resource signal is aligned.

In this embodiment, if the user equipment adopts an OFDM signal modulation mode on the uplink time-frequency resource, the subcarrier center of the D2D communication signal and the subcarrier of the uplink time-frequency resource signal may be performed when performing subcarrier mapping. Center alignment; thus, the signal of the D2D communication and the signal of the uplink time-frequency resource can be kept positive Intercourse, there will be no overlap and affect the quality of communication.

If the user equipment adopts the SC-FDM signal modulation mode on the downlink time-frequency resource, the sub-carrier center of the signal for performing D2D communication and the sub-carrier center of the signal of the downlink time-frequency resource may be aligned when performing sub-carrier mapping; This can make the signal of the D2D communication and the signal of the downlink time-frequency resource maintain orthogonality without overlapping with each other and affecting the communication quality.

In an embodiment, when the uplink time-frequency resource or the downlink time-frequency resource does not include the time-frequency resource adjacent to the zero-subcarrier; the user equipment moves the D2D communication signal that adopts the OFDM signal modulation mode to the left or the right. Half subcarrier, such that the center of the subcarrier of the D2D communication signal is aligned with the center of the subcarrier of the uplink time-frequency resource signal;

Alternatively, the user equipment moves the D2D communication signal in the SC-FDM signal modulation mode to the left or right by half a subcarrier, so that the subcarrier center of the D2D communication signal is aligned with the subcarrier center of the downlink time-frequency resource signal.

4 is a schematic diagram of a D2D signal moving to a left half of a subframe according to an embodiment of the present invention, and FIG. 5 is a schematic diagram of a D2D signal moving to a right half of a subframe according to an embodiment of the present invention. As shown in Fig. 4 or Fig. 5, before the data is moved, the mapping manner of the normal uplink/downlink signals is different from that of the D2D signals by half a subcarrier, which may cause aliasing.

As shown in FIG. 4 or FIG. 5, after the D2D signal is shifted to the left or right by half of the subcarriers, the subcarrier center of the D2D signal is aligned with the center of the subcarrier of the uplink/downlink time-frequency resource signal. Thereby, the orthogonality of the signals is maintained, and there is no possibility of aliasing and affecting the communication quality.

In another embodiment, where the uplink time-frequency resource includes a time-frequency resource adjacent to the zero-subcarrier, the method may further include: the user equipment cancels the zero-subcarrier; and the user equipment adopts an OFDM signal modulation manner. The D2D communication signal moves half a subcarrier to the left or right such that the subcarrier center of the D2D communication signal is aligned with the subcarrier center of the uplink time-frequency resource signal.

6 is a schematic diagram of canceling a zero subcarrier and moving a half subframe to the left/right to the right according to an embodiment of the present invention. As shown in Figure 6, when the uplink resource is occupied for D2D communication and the OFDM modulation mode is adopted, the subcarrier mapping may be shifted to the left or right by half of the subcarriers, and the zero subcarriers are cancelled. The subcarrier center of the D2D signal is aligned with the center of the subcarrier of the uplink time-frequency resource signal, thereby maintaining the orthogonality of the signals without aliasing and affecting the communication quality.

For example, the existing IFFT transform formula of OFDM can be expressed as follows (including subcarrier mapping corresponding), _s /2

j2A&f(tN _cpl T _s )

ν Σ»” ■ Σ j2A&f(tN _cpl T _s )

), where represents a time-continuous signal on the antenna port p of the downlink slot OFDM symbol /. For 0 _≤ "(W _CP ,, ₊ W)xr _s , where k, -, =^ ₊ L B3⁄4 ^B /2J and (+) = _B ^LB /2"_l For △ / = 15kHz, the variable W is 2048; For A/ = 7.5kHz, the variable W is 4096

In the case where the positive frequency side shifts to the left negative frequency side to the right, and the zero subcarrier is canceled,

-)= Lw 2"

In another embodiment, where the uplink time-frequency resource includes a time-frequency resource adjacent to the zero-subcarrier, the method may further include: the user equipment retains the zero-subcarrier; and the user equipment adopts an OFDM signal modulation manner. The D2D communication signal moves half a subcarrier to the left or right such that the subcarrier center of the D2D communication signal is aligned with the subcarrier center of the uplink time-frequency resource signal.

7 is a schematic diagram of a reserved zero subcarrier and a left/right shift of a half subframe according to an embodiment of the present invention. As shown in Figure 7, when the uplink resource is occupied for D2D communication and the OFDM modulation mode is adopted, the subcarrier mapping may be shifted to the left or right by half a subcarrier, and the original zero subcarrier is reserved. The subcarrier center of the D2D signal is aligned with the center of the subcarrier of the uplink time-frequency resource signal, thereby maintaining the orthogonality of the signals without aliasing and affecting the communication quality. Moreover, since the zero subcarriers are reserved, the influence of adjacent interference can be reduced.

For example, when moving half a subcarrier to the left and keeping the relative position of the original zero subcarrier unchanged,

Where 0 ≤ , <, N _CVJ +N)XT _s , k—, =k + LNRBN _S c ^B /2”

TV = 2048,

A/ = 15kHz, « for the serial number ^J) RE carries the content at antenna port p.

When moving half a subcarrier to the right and keeping the relative position of the original zero subcarrier unchanged,

^ ( · φ ₊ 1/2) Δ / (, - W _{CP S} ) + J _a ( . (+1/2) 4 (, - W _{CP S} ) where 0 ≤ , <, N _{CV 1} +N) xT _s ,

TV = 2048, A / = 15kHz, «RE is the serial number ^J) carried on the antenna port p. In another embodiment, where the uplink time-frequency resource includes a time-frequency resource adjacent to the zero-subcarrier, the method may further include: the user equipment retains the original zero-subcarrier and adds a new zero-subcarrier; And the user equipment moves the D2D communication signal in the OFDM signal modulation mode to the left or the right by half a subcarrier, so that the subcarrier center of the D2D communication signal is aligned with the subcarrier center of the uplink time-frequency resource signal.

FIG. 8 is a schematic diagram of adding a zero subcarrier and moving a half subframe to the left/right to the right according to an embodiment of the present invention. As shown in Figure 8, when the uplink resource is used for D2D communication and the OFDM modulation mode is adopted, the subcarrier mapping is shifted to the left or right by half a subcarrier, and a new zero is added in addition to the original zero subcarrier. Subcarrier. The subcarrier center of the D2D signal is aligned with the center of the subcarrier of the uplink time-frequency resource signal, thereby maintaining the orthogonality of the signals without aliasing and affecting the communication quality. Moreover, since the original zero carrier is retained and a new zero subcarrier is added, the influence of adjacent interference can be further reduced.

For example, when moving half a subcarrier to the left and adding a new zero subcarrier to the right of the original zero subcarrier,

(i- 1/ 2) Δ/(ί—

Where 0 ≤ ί <, N _CVJ + N)XT _s , k ⁽ -, = k + LNRBN _S c ^B /2", ⁽⁺⁾ =

, TV = 2048 , A / = 15 kHz , « for the serial number ^J) RE carried on the antenna port p. In the case of moving half a subcarrier to the right and adding a new zero subcarrier to the left of the original zero subcarrier,

Where 0 ≤ ί <, N _{CV 1} + N) x T _s , k -, = k + LN Nr /2", ⁽⁺⁾ = k + LNRB N _S c ^B /2" - 1, TV = 2048 , A/ = 15 kHz, «RE is the serial number of ^J) carried on the antenna port p.

In another embodiment, in the case that the downlink time-frequency resource does not include the time-frequency resource adjacent to the zero-subcarrier; the user equipment moves the D2D communication signal in the SC-FDM signal modulation mode to the left or the right by half. The carrier is such that the center of the subcarrier of the D2D communication signal is aligned with the center of the subcarrier of the downlink time-frequency resource signal.

FIG. 9 is a schematic diagram of moving a half subframe to the left/rightward according to an embodiment of the present invention. As shown in FIG. 9, when the downlink resource is occupied for D2D communication and the SC-FDM modulation mode is adopted, the subcarrier mapping is shifted to the left or right by half a subcarrier. The subcarrier center of the D2D signal is aligned with the center of the subcarrier of the downlink time-frequency resource signal, thereby maintaining the orthogonality of the signals without aliasing and affecting the communication quality.

For example, the existing IFFT transform formula of SC-FDM can be expressed as follows (including subcarrier mapping corresponding),

, where (- ) = [_O /2 丄 W = 2048, A / = 15kHz The serial number is ^, the content of the RE RE carried on the antenna port p.

In the case of moving half a subcarrier to the right (positive frequency direction), ! , : Σ

Where 0 ≤, <(W _CP , _{/ +} W)xr _s ,

The sequence number is ^, and the RE is carried on the antenna port p.

In the case of moving to the left (half subcarriers in the negative frequency direction,

among them, .

≤, <(W _CP , _{/ +} W)xr _s , k, -,

The sequence number is ^, and the RE is carried on the antenna port p.

In another embodiment, in the case that the downlink time-frequency resource does not include the time-frequency resource adjacent to the zero-subcarrier; the method may further include: adding, by the user equipment, the D2D communication signal in the SC-FDM signal modulation mode a new zero subcarrier; and the user equipment moves the D2D communication signal using the SC-FDM signal modulation mode to the left or right by half a subcarrier, so that the subcarrier center of the D2D communication signal is aligned with the subcarrier center of the downlink time-frequency resource signal .

FIG. 10 is a schematic diagram of adding a zero subcarrier and moving a half subframe to the left/right to the right according to an embodiment of the present invention. As shown in FIG. 10, when the downlink resource is occupied for D2D communication and the SC-FDM modulation mode is adopted, the subcarrier mapping is shifted to the left or right by half a subcarrier, and a zero subcarrier is added. The subcarrier center of the D2D signal is aligned with the center of the subcarrier of the downlink time-frequency resource signal, thereby maintaining the orthogonality of the signals without intermixing and affecting the communication quality. Moreover, the effect of adjacent interference can be further reduced due to the addition of new zero subcarriers.

For example, moving half of the subcarriers to the left and right, and one zero subcarrier,

Where 0 ≤ ί <, N _CVJ + N)XT _s , k ⁽ -, = k + LNRB N _S c ^B /2", ⁽⁺⁾ =

, TV = 2048 , A / = 15 kHz , « for the serial number ^J) RE carried on the antenna port p.

It is to be noted that FIG. 8 or FIG. 10 only shows the case where one zero subcarrier is added, but the present invention is not limited thereto, and for example, a plurality of zero subcarriers may be added. Further, the above-described formulas and the like are merely illustrative of the present invention, but the present invention is not limited thereto, and specific embodiments may be determined according to actual needs. The meaning of each symbol of the above formula can also be referred to the prior art.

Further, in the above embodiment, the case where the left sub-carrier is shifted left or right is taken as an example. However, the present invention is not limited thereto, and for example, one half, two halves, and the like may be shifted left or right. For example, you only need to align the subcarrier center, and you can determine the specific implementation according to the actual situation.

In this embodiment, the user equipment may predetermine whether to adopt the OFDM signal modulation mode, or use the SC-FDM signal modulation mode to perform D2D communication. The user equipment can be determined according to the dynamic signaling configuration on the base station side. For example, the base station can be dynamically configured through physical layer signaling, MAC layer signaling, or RRC signaling.

It can be seen from the above embodiment that the subcarrier center of the D2D communication signal adopting the OFDM signal modulation mode is aligned with the subcarrier center of the uplink time-frequency resource signal by the user equipment; or the sub-D2D communication signal of the SC-FDM signal modulation mode is used. The carrier center is aligned with the center of the subcarrier of the downlink time-frequency resource signal. The signal of the D2D communication and the signal of the uplink time-frequency resource can be made orthogonal, and there is no mutual aliasing and the communication quality is affected. Example 2

The embodiment of the invention provides a method for transmitting D2D communication, which is applied to the user equipment side. The user equipment uses the OFDM signal modulation mode on the uplink time-frequency resource or the SC-FDM signal modulation mode on the downlink time-frequency resource for D2D communication.

FIG. 11 is a schematic flow chart of a method for transmitting D2D communication according to an embodiment of the present invention. As shown in FIG. 11, the method includes:

Step 1101: The user equipment vacates one or more subcarriers in the D2D communication signal adopting the OFDM signal modulation mode, or vacates one or more subcarriers in the D2D communication signal adopting the SC-FDM signal modulation mode.

In this embodiment, since the interference of the adjacent subcarriers is the largest, by vacating one or more subcarriers, it is possible to suppress the mutual deviation between the OFDM modulation mode and the SC-FDM modulation mode of the existing LTE in the subcarrier mapping. The interference caused by half of the subcarriers.

In an embodiment, the user equipment vacates one or more subcarriers on a side of the D2D communication signal that adopts the OFDM signal modulation mode, and overlaps with the signal of the uplink time-frequency resource; or adopts an SC-FDM signal modulation mode. In the D2D communication signal, one or more subcarriers are vacant on the side of the signal aliasing with the downlink time-frequency resource.

Specifically, when performing subcarrier mapping, a mapping method corresponding to the signal modulation method may be employed (for example, the SC-FDM modulation method adopts the method shown in FIG. 1 and the OFDM modulation method uses the method shown in FIG. 2). And, one or more subcarriers are vacant on the side of the D2D communication signal that may be aliased with the adjacent normal uplink or downlink signals.

FIG. 12 is a schematic diagram of a left idle subcarrier on the left side of the embodiment of the present invention, and FIG. 13 is a schematic diagram of a left idle subcarrier on the right side of the embodiment of the present invention. As shown in FIG. 12 or 13, one or more subcarriers are vacant on a side that may be aliased with the uplink/downlink time-frequency resources, so that the D2D signals and the subcarriers of the normal uplink/downlink signals in the mixed signal are no longer Adjacent, thereby avoiding maximum interference between adjacent subcarriers and suppressing communication quality problems caused by signal aliasing.

In another embodiment, the user equipment vacates one or more subcarriers on both sides of the D2D communication signal adopting the OFDM signal modulation mode, or vacant ones on both sides of the D2D communication signal adopting the SC-FDM signal modulation mode. Multiple subcarriers.

Specifically, when performing subcarrier mapping, a mapping method corresponding to the signal modulation method may be employed (for example, the SC-FDM modulation method adopts the method shown in FIG. 1 and the OFDM modulation method uses the method shown in FIG. 2). On both sides of the D2D signal, one or more subcarriers may be vacant, and the number of vacant subcarriers on both sides may be different.

FIG. 14 is a schematic diagram of a null subcarrier on both sides according to an embodiment of the present invention. As shown in Figure 14, one or more subcarriers are vacant on both sides of the D2D signal to avoid maximum interference between adjacent subcarriers and to suppress communication quality problems caused by signal aliasing.

It can be seen from the above embodiment that the user equipment has one or more subcarriers in the D2D communication signal adopting the OFDM signal modulation mode; or the D2D communication signal in the SC-FDM signal modulation mode is hollow. One or more subcarriers. The signal of the D2D communication and the signal of the uplink time-frequency resource may be mixed with each other to avoid the maximum interference between adjacent subcarriers, and the communication quality problem caused by the aliasing of the signals is suppressed. Example 3

The embodiment of the invention provides a method for transmitting D2D communication, which is described from the base station side. The same contents as those of Embodiment 1 or 2 will not be described again.

FIG. 15 is a schematic diagram of a method for transmitting D2D communication according to an embodiment of the present invention. As shown in FIG. 15, the method includes:

Step 1501: The base station schedules the user equipment for D2D communication on a resource that is not adjacent to the zero subframe.

In this embodiment, the base station tries to avoid resources adjacent to the zero subcarriers (such as adjacent to the zero subcarriers).

The RB or the RE adjacent to the zero subcarrier schedules D2D communication. Then, on the user equipment side, the user equipment can perform subcarrier mapping by the method described in Embodiment 1 or 2.

As shown in FIG. 15, the method may further include:

Step 1502: The base station uses dynamic signaling to configure the user equipment to perform D2D communication by using an OFDM signal modulation mode or an SC-FDM signal modulation mode.

It should be noted that there is no sequence relationship between step 1501 and step 1502. Step 1502 may be performed first and then step 1501 may be performed. The specific implementation manner may be determined according to actual conditions.

It can be seen from the above embodiment that the base station schedules user equipment for D2D communication on resources that are not adjacent to the zero subframe. When the signal of the D2D communication and the signal of the uplink time-frequency resource appear to overlap each other, the maximum interference between adjacent sub-carriers is avoided, and the communication quality problem caused by the aliasing of the signals is suppressed. Example 4

The embodiment of the present invention provides a user equipment, which corresponds to the method for transmitting D2D communication in Embodiment 1, and the same content as Embodiment 1 is not described herein. The user equipment uses the OFDM signal modulation mode on the uplink time-frequency resource or the SC-FDM signal modulation mode on the downlink time-frequency resource to perform D2D communication.

FIG. 16 is a schematic structural diagram of a user equipment according to an embodiment of the present invention. As shown in FIG. 16, the user equipment 1600 includes: a first mapping unit 1601. Other parts of user equipment 1600 are not shown, reference may be made to the prior art.

The first mapping unit 1601 aligns the subcarrier center of the D2D communication signal in the OFDM signal modulation mode with the subcarrier center of the uplink time-frequency resource signal; or, the SC-FDM signal modulation side is used. The subcarrier center of the D2D communication signal is aligned with the subcarrier center of the downlink time-frequency resource signal.

It can be seen from the above embodiment that the subcarrier center of the D2D communication signal adopting the OFDM signal modulation mode is aligned with the subcarrier center of the uplink time-frequency resource signal by the user equipment; or the sub-D2D communication signal of the SC-FDM signal modulation mode is used. The carrier center is aligned with the center of the subcarrier of the downlink time-frequency resource signal. The signal of the D2D communication and the signal of the uplink time-frequency resource can be made orthogonal, and there is no mutual aliasing and the communication quality is affected. Example 5

The embodiment of the present invention provides a user equipment, which corresponds to the transmission method of the D2D communication in the second embodiment, and the same content as that of the embodiment 2 is not described again. The user equipment uses the OFDM signal modulation mode on the uplink time-frequency resource or the SC-FDM signal modulation mode on the downlink time-frequency resource to perform D2D communication.

FIG. 17 is a schematic structural diagram of a user equipment according to an embodiment of the present invention. As shown in FIG. 17, the user equipment 1700 includes: a second mapping unit 1701. Other portions of user equipment 1700 are not shown, reference may be made to the prior art.

The second mapping unit 1701 vacates one or more subcarriers in the D2D communication signal adopting the OFDM signal modulation mode; or, the one or more subcarriers are hollow in the D2D communication signal adopting the SC-FDM signal modulation mode.

It can be seen from the above embodiment that the user equipment has one or more subcarriers in the D2D communication signal adopting the OFDM signal modulation mode, or one or more subcarriers in the D2D communication signal in the SC-FDM signal modulation mode. When the signal of the D2D communication and the signal of the uplink time-frequency resource appear to be mutually aliased, the maximum interference between adjacent subcarriers is avoided, and the communication quality problem caused by the aliasing of the signals is suppressed. Example 6

The embodiment of the present invention provides a base station, which corresponds to the transmission method of the D2D communication in the third embodiment, and the same content as that of the third embodiment is not described again.

FIG. 18 is a schematic diagram of a structure of a base station according to an embodiment of the present invention. As shown in FIG. 18, the base station 1800 includes: a scheduling unit 1801. Other parts of the base station 1800 that are not shown in the drawings may be referred to the prior art.

The scheduling unit 1801 schedules the user equipment for D2D communication on resources that are not adjacent to the zero subframe. As shown in FIG. 18, the base station 1800 may further include: a configuration unit 1802, configured to configure, by using dynamic signaling, the user equipment to perform D2D communication by using an OFDM signal modulation manner or using an SC-FDM signal modulation manner. It can be seen from the above embodiment that the base station schedules the user equipment for D2D communication on resources that are not adjacent to the zero subframe. When the signals of the D2D communication and the signals of the uplink time-frequency resources appear to overlap each other, the maximum interference between adjacent subcarriers is avoided, and the communication quality problem caused by the aliasing of the signals is suppressed. Example 7

The embodiment of the present invention further provides a communication system, including the user equipment according to Embodiment 4, and the base station according to Embodiment 6, or the user equipment as described in Embodiment 5 and the base station according to Embodiment 6 .

FIG. 19 is a schematic diagram of a configuration of a communication system according to an embodiment of the present invention. As shown in FIG. 19, the communication system 1900 includes a user equipment 1901, a user equipment 1902, and a base station 1903. The user equipment 1901 may be the user equipment 1600, 1700 in the embodiment 4 or 5, and performs D2D communication with the user equipment 1902; the extreme cold 1903 may be the base station 1800 in the embodiment 6.

An embodiment of the present invention further provides a computer readable program, wherein when the program is executed in a user equipment, the program causes a computer to perform D2D communication as described in Embodiment 1 or 2 above in the user equipment. Transmission method.

The embodiment of the present invention further provides a storage medium storing a computer readable program, wherein the computer readable program causes the computer to execute a transmission method of D2D communication as described in Embodiment 1 or 2 above in the user equipment.

The embodiment of the present invention further provides a computer readable program, wherein when the program is executed in a base station, the program causes a computer to execute a transmission method of D2D communication as described in Embodiment 3 above in the base station.

The embodiment of the present invention further provides a storage medium storing a computer readable program, wherein the computer readable program causes a computer to execute a transmission method of D2D communication as described in Embodiment 3 above in a base station.

The above apparatus and method of the present invention may be implemented by hardware, or may be implemented by hardware in combination with software. The present invention relates to a computer readable program that, when executed by a logic component, enables the logic component to implement the apparatus or components described above, or to cause the logic component to implement the various methods described above Or steps. The present invention also relates to a storage medium for storing the above program, such as a hard disk, a magnetic disk, an optical disk, a DVD, a flash memory, or the like. One or more of the functional blocks described in the figures and/or one or more combinations of functional blocks may be implemented as a general purpose processor, digital signal processor (DSP) for performing the functions described herein. ), application specific integrated circuit (ASIC), field programmable gate array (FPGA) or other programmable logic device, discrete Gate or transistor logic, discrete hardware components, or any suitable combination thereof. One or more of the functional blocks described with respect to the figures and/or one or more combinations of functional blocks may also be implemented as a combination of computing devices, eg, a combination of a DSP and a microprocessor, multiple microprocessors One or more microprocessors in conjunction with DSP communication or any other such configuration.

The present invention has been described in connection with the specific embodiments thereof, and it should be understood by those skilled in the art that these descriptions are not intended to limit the scope of the invention. A person skilled in the art can make various modifications and changes to the invention in accordance with the spirit and the principles of the invention, which are also within the scope of the invention.

Claims

claims

1. A transmission method for D2D communication. The user equipment adopts the OFDM signal modulation method on the uplink time-frequency resources or uses the SC-FDM signal modulation method on the downlink time-frequency resources to perform D2D communication. The method includes:

The user equipment aligns the subcarrier center of the D2D communication signal using the OFDM signal modulation method with the subcarrier center of the uplink time-frequency resource signal; or

The user equipment aligns the subcarrier center of the D2D communication signal using the SC-FDM signal modulation method with the subcarrier center of the downlink time-frequency resource signal.

2. The transmission method according to claim 1, wherein, when the uplink time-frequency resource or the downlink time-frequency resource does not include a time-frequency resource adjacent to zero subcarrier;

The user equipment moves the D2D communication signal using the OFDM signal modulation mode by half a subcarrier to the left or right, so that the subcarrier center of the D2D communication signal is aligned with the subcarrier center of the uplink time-frequency resource signal; or

The user equipment moves the D2D communication signal using the SC-FDM signal modulation mode by half a subcarrier to the left or right, so that the subcarrier center of the D2D communication signal is aligned with the subcarrier center of the downlink time-frequency resource signal.

3. The transmission method according to claim 1, wherein when the uplink time-frequency resources include time-frequency resources adjacent to zero subcarriers; the method further includes:

The user equipment cancels the zero subcarrier; and

The user equipment moves the D2D communication signal using the OFDM signal modulation mode by half a subcarrier to the left or right, so that the subcarrier center of the D2D communication signal is aligned with the subcarrier center of the uplink time-frequency resource signal.

4. The transmission method according to claim 1, wherein when the uplink time-frequency resources include time-frequency resources adjacent to zero subcarriers; the method further includes:

The user equipment reserves the zero subcarrier; and

5. The transmission method according to claim 1, wherein when the uplink time-frequency resources include time-frequency resources adjacent to zero subcarriers; the method further includes:

The user equipment reserves the zero subcarrier and adds a new zero subcarrier; and

6. The transmission method according to claim 1, wherein the method further includes:

The user equipment adds a new zero subcarrier to the D2D communication signal using the SC-FDM signal modulation method; and

7. The transmission method according to claim 1, wherein the method further includes:

The user equipment determines to use the OFDM signal modulation method or the SC-FDM signal modulation method for D2D communication according to the dynamic signaling configuration on the base station side.

8. A transmission method for D2D communication. The user equipment uses the OFDM signal modulation method on the uplink time-frequency resources, or uses the SC-FDM signal modulation method on the downlink time-frequency resources to perform D2D communication. The method includes:

The user equipment leaves one or more subcarriers vacant in the D2D communication signal using OFDM signal modulation; or

The user equipment leaves one or more subcarriers vacant in the D2D communication signal using the SC-FDM signal modulation method.

9. The transmission method according to claim 8, wherein in the D2D communication signal using the OFDM signal modulation method, the user equipment leaves the one vacant on the side that overlaps with the signal of the uplink time-frequency resource or multiple subcarriers; or

In the D2D communication signal using the SC-FDM signal modulation method, the user equipment leaves the one or more subcarriers vacant on the side that overlaps with the signal of the downlink time-frequency resource.

10. The transmission method according to claim 8, wherein the user equipment leaves the one or more subcarriers vacant on both sides of the D2D communication signal using OFDM signal modulation; or The user equipment leaves the one or more subcarriers vacant on both sides of the D2D communication signal using the SC-FDM signal modulation method.

11. The transmission method according to claim 8, wherein the method further includes:

12. A transmission method for D2D communication, the method includes:

The base station schedules the user equipment for D2D communication on resources that are not adjacent to the zero subframe.

13. The transmission method according to claim 12, wherein the method further includes:

The base station uses dynamic signaling to configure the user equipment to use OFDM signal modulation or SC-FDM signal modulation for D2D communication.

14. A user equipment that uses OFDM signal modulation on uplink time-frequency resources or SC-FDM signal modulation on downlink time-frequency resources to perform D2D communication. The user equipment includes:

The first mapping unit aligns the subcarrier center of the D2D communication signal using the OFDM signal modulation method with the subcarrier center of the uplink time-frequency resource signal; or, aligns the subcarrier center of the D2D communication signal using the SC-FDM signal modulation method with the subcarrier center of the uplink time-frequency resource signal. The subcarrier centers of downlink time-frequency resource signals are aligned.

15. A user equipment that uses OFDM signal modulation on uplink time-frequency resources or SC-FDM signal modulation on downlink time-frequency resources to perform D2D communication. The user equipment includes:

The second mapping unit vacates one or more subcarriers in the D2D communication signal using the OFDM signal modulation method; or, vacates one or more subcarriers in the D2D communication signal using the SC-FDM signal modulation method.

16. A base station, the base station includes:

The scheduling unit schedules the user equipment to perform D2D communication on resources that are not adjacent to the zero subframe.

17. The base station according to claim 16, wherein the base station further includes:

The configuration unit uses dynamic signaling to configure the user equipment to use the OFDM signal modulation method or the SC-FDM signal modulation method to perform D2D communication.

18. A communication system, comprising the user equipment as claimed in claim 14 or 15, and the base station as claimed in claim 15 or 16.

19. A computer-readable program, wherein when the program is executed in the user equipment, the program causes the computer to perform the transmission method of D2D communication according to any one of claims 1 to 11 in the user equipment. .

20. A storage medium storing a computer-readable program, wherein the computer-readable program causes the computer to execute the transmission method of D2D communication according to any one of claims 1 to 11 in the user equipment.

21. A computer-readable program, wherein when the program is executed in a base station, the program causes the computer to execute the transmission method of D2D communication as claimed in claim 12 or 13 in the base station.

22. A storage medium storing a computer-readable program, wherein the computer-readable program causes the computer to perform the transmission method of D2D communication according to claim 12 or 13 in the base station.