CN105101431A

CN105101431A - Device-to-Device communication method, apparatus and system

Info

Publication number: CN105101431A
Application number: CN201410510078.8A
Authority: CN
Inventors: 吴栓栓; 袁弋非; 张峻峰; 贺海港; 黄双红
Original assignee: ZTE Corp
Current assignee: ZTE Corp
Priority date: 2014-05-07
Filing date: 2014-09-28
Publication date: 2015-11-25
Anticipated expiration: 2034-09-28
Also published as: WO2016045442A1; CN105101431B

Abstract

The invention discloses a device-to-device (D2D) communication method, apparatus and system, wherein the method includes: receiving a first resource configuration message of the D2D from a network node, and determining D2D resource sets according to the first resource configuration message; and transmitting device to D2D signals in the resource sets, wherein the resource sets are distributed periodically, and each resource period includes a plurality of resource units divided by a time division multiplexing mode and/or a frequency division multiplexing mode.

Description

Device-to-device communication method, device and system

Technical Field

The present invention relates to device-to-device (D2D) communication technology in the field of mobile communication, and in particular, to a D2D communication method, apparatus and system.

Background

In a cellular communication system, when there is traffic transmission between two User Equipments (UEs), when UE1 and UE2 are located in the same cell and are close to each other, although the two UEs are covered by the cell of the same base station, data transmission still needs to be relayed through a core network, and one data transmission still consumes radio spectrum resources on two links. It can be seen that the above-described cellular communication method is clearly not optimal. With diversification of mobile communication services, for example, popularization of applications such as social networks, electronic payments, and the like in wireless communication systems, service transmission demands among close-range users are increasing. Device-to-Device (D2D) communication modes are of increasing interest. For users of short-range communication, D2D not only saves wireless spectrum resources, but also reduces data transmission pressure of the core network.

In cellular communication, when two UEs communicate, the UEs do not generally know the location of the other UE, but establish a connection between the two UEs through a network side device (base station or core network device). For D2D communication, the premise for establishing a communication link is mutual discovery between UEs, i.e., UEs have a proximity relationship. One way to implement device discovery is through the transmission and detection of device discovery signals. And the performance of device discovery is related to the load of the device discovery signal. For example, when the load of the device discovery signal is large, how to ensure or improve the performance of device discovery is an urgent problem to be solved in the related art. In addition, during the device-to-device communication, a terminal transmission control signaling (or called scheduling assignment) needs to be sent to indicate the relevant data channel. The transmission manner of the control signaling is also a problem to be considered in the related art.

Disclosure of Invention

In order to solve the above technical problems, the present invention provides a D2D communication method, device and system.

The embodiment of the invention provides a D2D communication method, which comprises the following steps:

receiving a D2D first resource configuration message from a network node;

determining a set of D2D resources from the first resource configuration message;

transmitting the device-to-D2D signal within the set of resources;

the resource sets are periodically distributed, and each resource period comprises a plurality of resource units which are divided in a time division multiplexing and/or frequency division multiplexing mode.

In the above scheme, the method further comprises:

determining, from the set of resources, a location of a dedicated resource unit for transmitting a D2D signal, and transmitting the D2D signal in the dedicated resource unit;

the dedicated resource unit comprises a plurality of resource units which are discretely distributed in a time domain and/or a frequency domain according to a preset rule;

the discrete distribution mode comprises at least one of the following modes:

the frequency locations of the plurality of resource units are not contiguous;

a temporal location of the plurality of resource units is discontinuous;

the frequency location and the time location of the plurality of resource units are not contiguous.

In the foregoing scheme, determining the location of the dedicated resource unit for transmitting the D2D signal includes:

determining the position of a virtual resource for transmitting the D2D signal, and determining the position of a dedicated resource unit for transmitting the D2D signal according to the position of the virtual resource.

In the foregoing scheme, determining the virtual resource location for transmitting the D2D signal includes:

randomly selecting the position of the virtual resource unit from a virtual resource candidate set;

or,

receiving a D2D second resource configuration message from a network node, wherein the second resource configuration message is used to indicate at least a location of the virtual resource.

determining the position of a specific resource unit in the plurality of resource units for transmitting the D2D signal, and determining the positions of other resource units in the plurality of resource units for transmitting the D2D signal according to the position of the specific resource unit and the preset rule, wherein the position of the specific resource unit and the positions of the other resource units are taken as the positions of the dedicated resources.

In the foregoing solution, determining a location of a specific resource unit in a plurality of resource units used for transmitting the D2D signal includes:

randomly selecting a location of the particular resource unit in a candidate set of resource units;

or,

receiving, from the network node, a device-to-device second resource configuration message indicating at least a location of the particular resource unit.

In the above scheme, the preset rule is: the frequency domain position interval of two adjacent resource units in the plurality of resource units for transmitting the D2D signal is K/2; or, the frequency domain position intervals of two adjacent resource units in the plurality of resource units for transmitting the D2D signal are K/m;

wherein, K is the number of available resource units in the frequency domain for the device-to-device communication, and m is the number of resource units used for transmitting the D2D signal in one resource cycle.

In the above scheme, the preset rule is: the time domain position interval of two adjacent resource units in the plurality of resource units for transmitting the D2D signal is L/2;

or, the time domain position interval of two adjacent resource units in the plurality of resource units for transmitting the D2D signal is L/n;

or, the time domain position interval of two adjacent resource units in the plurality of resource units for transmitting the D2D signal is L1/2;

or, the time domain position interval of two adjacent resource units in the plurality of resource units for transmitting the D2D signal is L1/n;

wherein L is the number of time domain available resource units in a resource period for the device-to-device communication, L1 is the number of time domain available resource units per resource group in a resource period for the device-to-device communication, and n is the number of dedicated resource units for the D2D signaling in one resource period.

In the above scheme, the method further comprises:

grouping resource units in a resource period in a time domain according to the number of dedicated resource units in the resource period, so that the number of available resource units in the time domain in each resource unit group is the same as the number of dedicated resource units for the D2D signal transmission;

the resource elements are used for D2D signaling; the D2D signal is transmitted within one of the resource packets.

In the above scheme, the method further comprises:

determining the positions of other resource units in the plurality of resource units for transmitting the D2D signal according to the position (l, k) of the specific resource unit and the preset rule;

wherein the specific resource unit is a first resource unit which transmits the D2D signal in the resource period;

the preset rule is as follows: the time position of the ith resource unit transmitting the D2D signal is mod (L + (i-1) L/m, L), or mod (L + (i-1) L1/m, L1), or L + i-1;

and/or the frequency position of the i-th resource unit transmitting the D2D signal is mod (K + (i-1) K/m, K), or mod (K + mod (i-1, 2) K/2, K), or K;

wherein i is a positive integer less than or equal to m.

In the above scheme, the D2D signal is a discovery signal used for device discovery or a physical channel carrying a discovery signal; or,

the D2D signal is control signaling for device communication, or scheduling assignment information, or a physical channel carrying the control signaling or information.

In the above scheme, the resource unit in the resource cycle includes a plurality of resource groups in the time domain;

each of the resource packets includes time-domain contiguous subframes for transmission of signals for the device-to-device communication;

the resource groups are distributed discretely and the number of the subframes in different resource groups is the same in one resource period.

In the foregoing scheme, the manner of determining the number of consecutive subframes in the time domain includes at least one of:

the number of the continuous subframes is not more than the length of an uplink semi-persistent scheduling interval, and the semi-persistent scheduling interval is the minimum value of the semi-persistent scheduling interval allowed by the cellular communication system;

the number of the continuous subframes is not more than the round trip time of the uplink hybrid automatic repeat request;

the number of the continuous subframes is not more than the number of continuous uplink subframes in a subframe uplink and downlink configuration 0 of the time division duplex cellular communication system;

the number of the continuous subframes is not more than the number of continuous uplink subframes in the subframe uplink and downlink configuration 3 of the time division duplex cellular communication system;

the number of the continuous subframes is not more than the number of continuous uplink subframes in the uplink and downlink configuration of the subframes configured by the time division duplex cellular communication system.

The real-time embodiment of the present invention further provides a D2D communication method, including:

generating a D2D first resource configuration message;

sending the D2D first resource configuration message to a D2D User Equipment (UE); the first resource configuration message is for allocating at least a set of D2D resources for signaling of the device-to-device communication;

the resource set is periodically distributed, and each resource period comprises a plurality of resource units which are divided in a time division multiplexing and/or frequency division multiplexing mode; the set of resources is for the D2D user device to transmit D2D signals.

In the above scheme, the method further comprises: sending a D2D second resource configuration message;

wherein the second resource configuration message comprises: indicating a location of a particular resource unit of a plurality of resource units transmitting the D2D signal; or indicating the position of the virtual resource, wherein the position of the virtual resource has a preset mapping relation with a plurality of resource units for transmitting the D2D signal.

In the foregoing solution, the second resource configuration message includes: a time domain resource indication parameter and a frequency domain resource indication parameter;

wherein the time domain resource indication parameter is used for indicating the time domain position of a specific resource unit in a plurality of resource units transmitting the D2D signal in one resource period to the user equipment;

the frequency domain resource indication parameter is used for indicating the frequency domain position of a specific resource unit in a plurality of resource units transmitting the D2D signal in one resource period to user equipment;

the frequency domain resource indication parameter is indicated in the form of an index or a bitmap;

the time domain resource indication parameter is indicated in an index form, and the maximum value of the index is Kt-1 or Kt/m-1 or Kt/m;

wherein, Kt is the total number of the available resource units in time domain D2D in the resource period or the maximum number of the available resource units in time domain D2D allowed in the resource period, and m is the number of the resource units D2D occupied by the D2D signal during transmission in a resource period.

receiving a configuration message for a D2D resource from a network node;

determining a set of resources for the D2D communication from the configuration message;

detecting a D2D signal in the set of resources;

the configuration message is at least used for indicating a resource set for detecting the D2D signal, where the resource set is periodically distributed, and each resource period includes a plurality of resource units divided in a time division multiplexing and/or frequency division multiplexing manner; accordingly, in one resource period, the D2D signal is transmitted in a plurality of resource units, and the plurality of resource units are distributed discretely in the time domain and/or the frequency domain according to a preset rule.

In the above scheme, the frequency domain discrete distribution is that the frequency locations occupied by the plurality of resource units are discontinuous;

the time domain discrete distribution is discontinuous in time domain positions occupied by the plurality of resource units;

the frequency domain and the time domain are distributed discretely, so that the frequency domain positions and the time positions occupied by the resource units are discontinuous.

In the above solution, the resource units in a resource cycle are grouped in the time domain according to the number of the dedicated resource units in a resource cycle, and the number of the time domain available resource units in each resource group is the same as the number of the dedicated resource units used for the D2D signal transmission;

the resource elements are used for D2D signaling.

In the scheme, the position of a specific resource unit in a plurality of resource units for transmitting the D2D signal is determined;

determining the positions of other resource units in the plurality of resource units for transmitting the D2D signal according to the position of the specific resource unit and the preset rule;

detecting the D2D signal in the particular resource and the other resource elements.

In the above scheme, the positions of other resource units in the plurality of resource units for transmitting the D2D signal are determined according to the position (l, k) of the specific resource unit and the preset rule, where the specific resource unit is the first resource unit in the resource cycle to transmit the D2D signal;

and/or the presence of a gas in the gas,

the frequency location of the i-th resource unit transmitting the D2D signal is mod (K + (i-1) K/m, K), or mod (K + mod (i-1, 2) K/2, K), or K;

wherein i is a positive integer less than or equal to m.

An embodiment of the present invention provides a user equipment, including:

a first communication unit to receive a D2D first resource configuration message from a network node;

a baseband processing unit, configured to determine a D2D resource set according to the first resource configuration message;

a second communication unit to signal the device-to-device communication within the set of D2D resources;

wherein the set of resources is used for signaling of the device-to-device communication; the resource sets are periodically distributed, and each resource period comprises a plurality of resource units which are divided in a time division multiplexing and/or frequency division multiplexing mode.

In the foregoing solution, the second communication unit is configured to send the D2D signal in the dedicated resource unit;

correspondingly, the baseband processing unit is further configured to determine, from the resource set, a location of a dedicated resource unit for transmitting a D2D signal;

the dedicated resource units are a plurality of resource units which are discretely distributed in a time domain and/or a frequency domain according to a preset rule;

the discrete distribution mode comprises at least one of the following modes:

the frequency locations of the plurality of resource units are not contiguous;

a temporal location of the plurality of resource units is discontinuous;

In the foregoing solution, the baseband processing unit is specifically configured to determine a location of a virtual resource used for transmitting the D2D signal, and determine locations of a plurality of resource units used for transmitting the D2D signal as locations of the dedicated resource units according to the location of the virtual resource.

In the foregoing solution, the baseband processing unit is specifically configured to randomly select a position of the virtual resource unit from a virtual resource candidate set;

or,

receiving, by the first communication unit, a D2D second resource configuration message from the network node, wherein the second resource configuration message is at least for indicating a location of the virtual resource.

In the foregoing solution, the baseband processing unit is specifically configured to determine a location of a specific resource unit in the multiple resource units used for transmitting the D2D signal, determine locations of other resource units in the multiple resource units used for transmitting the D2D signal according to the location of the specific resource unit and the preset rule, and use the location of the specific resource unit and the locations of the other resource units as the locations of the dedicated resources.

In the foregoing solution, the baseband processing unit is specifically configured to randomly select a location of the specific resource unit from a resource unit candidate set;

or,

receiving, by the first communication unit, a device-to-device second resource configuration message from the network node, the second resource configuration message indicating at least a location of the particular resource unit.

In the foregoing solution, the baseband processing unit is further configured to group, in a time domain, the resource units in a resource period according to the number of dedicated resource units in the resource period, so that the number of available resource units in the time domain in each resource unit group is the same as the number of dedicated resource units used for the D2D signal transmission;

In the foregoing solution, the baseband processing unit is further configured to determine, according to the location (l, k) of the specific resource unit and the preset rule, locations of other resource units in the multiple resource units for transmitting the D2D signal;

wherein i is a positive integer less than or equal to m.

the D2D signal is a signal used for control signaling for device communication, or scheduling assignment information transmission, or a physical channel carrying the signal.

An embodiment of the present invention provides a network node, including:

a configuration module to generate a D2D first resource configuration message; the first resource configuration message is for allocating at least a set of D2D resources for signaling of the device-to-device communication; the resource set is periodically distributed, and each resource period comprises a plurality of resource units which are divided in a time division multiplexing and/or frequency division multiplexing mode; the set of resources is for the D2D user device to transmit D2D signals;

a sending module, configured to send the D2D first resource configuration message to a D2D User Equipment (UE).

In the foregoing scheme, the sending module is further configured to send a D2D second resource configuration message;

wherein the second resource configuration message comprises a location indicating a first one of a plurality of resource elements transmitting the D2D signal; or indicating the position of the virtual resource, wherein the position of the virtual resource has a preset mapping relation with a plurality of resource units for transmitting the D2D signal.

An embodiment of the present invention provides a user equipment, including:

a first communication module to receive a configuration message for a D2D resource from a network node; wherein the configuration message comprises at least: indicating a resource set used for detecting the D2D signal, wherein the resource set is periodically distributed, and each resource period comprises a plurality of resource units divided in a time division multiplexing and/or frequency division multiplexing manner; correspondingly, in one resource period, the D2D signal is transmitted in a plurality of resource units, and the plurality of resource units are distributed discretely in the time domain and/or the frequency domain according to a preset rule;

a baseband processing module to determine a set of resources for the D2D communication from the configuration message;

a second communication module to detect a D2D signal in the set of resources.

In the above scheme, the preset rule is: the frequency domain position interval of the resource units used for transmitting the D2D signal is K/2; or, the frequency domain position intervals of a plurality of resource units used for transmitting the D2D signal are K/m;

wherein K is the number of available resource units in the frequency domain for device-to-device communication, and m is the number of resource units used for transmitting the D2D signal in one resource cycle.

In the above scheme, the preset rule is: the time domain position intervals of a plurality of resource units used for transmitting the D2D signal are L/2;

or, the time domain position intervals of a plurality of resource units used for transmitting the D2D signal are L/n;

or, the time domain position interval of the plurality of resource units for transmitting the D2D signal is L1/2;

or, the time domain position intervals of the plurality of resource units for transmitting the D2D signal are L1/n;

wherein L is the number of time domain available resource units in a resource period for device-to-device communication, L1 is the number of time domain available resource units per resource group in a resource period for device-to-device communication, and n is the number of resource units for the D2D signal transmission in one resource period.

In the foregoing solution, the baseband processing module is specifically configured to group, in a time domain, the resource units in a resource period according to the number of dedicated resource units in the resource period, where the number of time-domain available resource units in each resource group is the same as the number of dedicated resource units used for D2D signal transmission; the resource elements are used for D2D signaling.

In the foregoing solution, the baseband processing module is specifically configured to determine a location of a specific resource unit in a plurality of resource units used for transmitting the D2D signal; determining the positions of other resource units in the plurality of resource units for transmitting the D2D signal according to the position of the specific resource unit and the preset rule; detecting the D2D signal in the particular resource and the other resource elements.

In the foregoing solution, the baseband processing module is specifically configured to determine, according to a location (l, k) of the specific resource unit and the preset rule, locations of other resource units in the multiple resource units for transmitting the D2D signal, where the specific resource unit is a first resource unit in the resource cycle for transmitting the D2D signal;

and/or the presence of a gas in the gas,

wherein i is a positive integer less than or equal to m.

An embodiment of the present invention provides a device-to-device communication system, where the system includes:

a user equipment for receiving a D2D first resource configuration message from a network node; determining a resource for transmitting a D2D signal according to the first resource configuration message;

a network node for generating a D2D first resource configuration message; and sending the D2D first resource configuration message to the D2D user equipment.

The D2D communication method, device and system provided by the invention can determine the resource for transmitting the discovery signal according to the configuration message sent by the network node, so as to send the D2D discovery signal on the resource, thus the transmission problem of the device discovery signal and the control signaling during the device-to-device communication can be solved, and the method can enable the device-to-device signal to obtain frequency diversity and/or time diversity gain on the premise of not increasing the complexity of terminal realization and signaling overhead, thereby obviously improving the transmission performance of the signal or the signaling; in another aspect, the present invention provides a method for ensuring compatibility of D2D communication with cellular link uplink communication while allocating resources for device-to-device communication by grouping sets of resources in a device-to-device resource period.

Drawings

Fig. 1 is a first flowchart illustrating a device-to-device communication method according to an embodiment of the present invention;

fig. 2 is a flowchart illustrating a device-to-device communication method according to an embodiment of the present invention;

fig. 3 is a third schematic flowchart of a device-to-device communication method according to an embodiment of the present invention;

fig. 4 is a schematic diagram of a communication resource partitioning structure;

fig. 5 is a schematic diagram of a network deployment of a cellular wireless communication system;

FIG. 6 is an example one of a D2D resource configuration;

FIG. 7 is an example two of a D2D resource configuration;

FIG. 8 is an example three of a D2D resource configuration;

FIG. 9 is an example four of a D2D resource configuration;

FIG. 10 is an example five of a D2D resource configuration;

FIG. 11 is an example six of a D2D resource configuration;

fig. 12 is an example seven of a D2D resource configuration;

FIG. 13 is an example eight of a D2D resource configuration;

FIG. 14 is an example nine of a D2D resource configuration;

FIG. 15 is an example ten of a D2D resource configuration;

FIG. 16 is an example eleven of a D2D resource configuration;

FIG. 17 is an example twelve of a D2D resource configuration;

FIG. 18 is an example thirteen of a D2D resource configuration;

FIG. 19 is a schematic diagram of a system configuration according to an embodiment of the present invention;

fig. 20 is a schematic diagram of a network node structure according to an embodiment of the present invention;

fig. 21 is a schematic diagram of a user equipment composition structure according to an embodiment of the present invention.

Detailed Description

The present invention will be described in further detail with reference to the accompanying drawings and specific embodiments.

The first embodiment of the method,

The present embodiment provides a device-to-device communication method, as shown in fig. 1, including:

step 101: receiving a D2D first resource configuration message from a network node;

step 102: determining a set of D2D resources from the first resource configuration message;

step 103: transmitting the device-to-D2D signal within the set of resources.

Specifically, the step 103 may be to determine, from the resource set, a location of a dedicated resource unit for transmitting a D2D signal, and transmit the D2D signal in the dedicated resource unit.

Here, the set of resources is used for signaling of the device-to-device communication; the resource sets are periodically distributed, and each resource period comprises a plurality of resource units which are divided in a time division multiplexing and/or frequency division multiplexing mode.

the discrete distribution mode comprises at least one of the following modes:

the frequency locations of the plurality of resource units are not contiguous;

a temporal location of the plurality of resource units is discontinuous;

Preferably, the determining the location of the dedicated resource unit for transmitting the D2D signal may include: determining the position of a virtual resource for transmitting the D2D signal, and determining the positions of a plurality of resource units for transmitting the D2D signal as the positions of the dedicated resource units according to the positions of the virtual resource.

Wherein the determining a virtual resource location for transmitting the D2D signal comprises:

randomly selecting the position of the virtual resource unit from a virtual resource candidate set; alternatively, a second resource configuration message is received from a network node, D2D, wherein the second resource configuration message is used to indicate at least a location of the virtual resource.

Wherein the virtual resource candidate set corresponds to a device-to-device communication resource within one resource period of the resource set; or a device-to-device communication resource in a resource grouping within a resource period in the set of resources.

Preferably, the determining the location of the dedicated resource unit for transmitting the D2D signal may include: determining the position of a specific resource unit in the plurality of resource units for transmitting the D2D signal, and determining the positions of other resource units in the plurality of resource units for transmitting the D2D signal according to the position of the specific resource unit and the preset rule, wherein the position of the specific resource unit and the positions of the other resource units are taken as the positions of the dedicated resources.

Wherein determining a location of a particular resource unit of the plurality of resource units used to transmit the D2D signal comprises: randomly selecting a location of the particular resource unit in a candidate set of resource units; alternatively, a device-to-device second resource configuration message is received from the network node, the second resource configuration message indicating at least a location of the particular resource unit.

The resource unit candidate set is a device-to-device communication resource in one resource period in the resource set; or a device-to-device resource in a resource grouping within a resource period in the resource set.

Preferably, the preset rule may be: the frequency domain position interval of two adjacent resource units in the plurality of resource units for transmitting the D2D signal is K/2; or, the frequency domain position intervals of two adjacent resource units in the plurality of resource units for transmitting the D2D signal are K/m; wherein K is the number of available resource units in the frequency domain for device-to-device communication, and m is the number of resource units used for transmitting the D2D signal in one resource cycle.

Preferably, the preset rule may further be: the time domain position interval of two adjacent resource units in the plurality of resource units for transmitting the D2D signal is L/2;

The D2D signal is a discovery signal for device discovery or a physical channel carrying a discovery signal; or, the D2D signal is control signaling for device communication, or scheduling assignment information, or a physical channel carrying the control signaling or information.

The preset mapping mode is as follows: randomly selecting a location of the particular resource unit or a location of the virtual resource unit; or receiving a device-to-device second resource configuration message, and determining the location of the specific resource unit or the location of the virtual resource according to the indication of the second resource configuration message.

The resource unit in the resource cycle comprises a plurality of resource groups in the time domain; each of the resource packets includes time-domain contiguous subframes for transmission of signals for the device-to-device communication;

The manner of determining the number of the time-domain consecutive subframes comprises at least one of the following:

Preferably, the method for grouping the resource units may specifically include: grouping resource elements within a resource period in the time domain according to the number of dedicated resource elements for the D2D signaling within the resource period, the number of time domain available resource elements within each resource group being the same as the number of dedicated resource elements for the D2D signaling; the D2D signal is transmitted within one of the resource packets. The resource elements are used for D2D signaling; the D2D signal is transmitted within one of the resource packets.

The method further comprises the following steps: determining the positions of other resource units in the plurality of resource units for transmitting the D2D signal according to the position (l, k) of the specific resource unit and the preset rule; wherein the specific resource unit is a first resource unit which transmits the D2D signal in the resource period;

and/or the frequency position of the i-th resource unit transmitting the D2D signal is mod (K + (i-1) K/m, K), or mod (K + mod (i-1, 2) K/2, K), or K; wherein i is a positive integer less than or equal to m.

It should be noted that "first" in "first resource unit" is a logical concept, and is only for convenience of description of the scheme. In theory, any resource unit that transmits the D2D signal may be the "first resource unit".

Method examples II,

The present embodiment provides a device-to-device communication method, as shown in fig. 2, including:

step 201: generating a D2D first resource configuration message;

step 202: sending the D2D first resource configuration message to a D2D User Equipment (UE), the first resource configuration message at least for allocating a set of D2D resources for signaling of the device-to-device communication. The resource set is periodically distributed, and each resource period comprises a plurality of resource units which are divided in a time division multiplexing and/or frequency division multiplexing mode; the set of resources is for the D2D user device to transmit D2D signals.

The set of resources is for the D2D user device to transmit D2D signals, including: the D2D user equipment determines the position of a dedicated resource unit for transmitting the D2D signal from the resource set, and transmits the D2D signal in the dedicated resource unit;

wherein the discrete distribution mode comprises at least one of the following modes:

the frequency locations of the plurality of resource units are not contiguous;

a temporal location of the plurality of resource units is discontinuous;

Preferably, the preset rule may be: the frequency domain position interval of two adjacent resource units in the plurality of resource units for transmitting the D2D signal is K/2; or, the frequency domain position intervals of two adjacent resource units in the plurality of resource units for transmitting the D2D signal are K/m;

Preferably, while performing steps 201-202, or before or after performing step 202, the method may further comprise: sending a D2D second resource configuration message;

wherein the second resource configuration message includes a location indicating a particular resource unit of a plurality of resource units that transmitted the D2D signal; or indicating the position of the virtual resource, wherein the position of the virtual resource has a preset mapping relation with a plurality of resource units for transmitting the D2D signal.

Preferably, the second resource configuration message may further include: a time domain resource indication parameter and a frequency domain resource indication parameter;

the frequency domain resource indication parameter is used for indicating the time domain position of a specific resource unit in a plurality of resource units transmitting the D2D signal in one resource period to user equipment;

the time domain resource indication parameter is indicated in an index form, and the maximum value of the index is Kt-1 or Kt/m-1 or Kt/m-1;

For the index, values can be taken from 0, or values can be taken from 1. For example, when the maximum index value is Kt-1 or Kt/m-1, the value is taken from 0; when the maximum index value is Kt or Kt/m < -1 >, the value is taken from 1.

The resource unit in the resource cycle comprises a plurality of resource groups in the time domain;

Method examples III,

The present embodiment provides a device-to-device communication method, as shown in fig. 3, the method includes:

step 301: receiving a configuration message for a D2D resource from a network node;

step 302: determining a set of resources for the D2D communication from the configuration message;

step 303: detecting a D2D signal in the set of resources.

Wherein the configuration message comprises at least: indicating a resource set used for detecting the D2D signal, wherein the resource set is periodically distributed, and each resource period comprises a plurality of resource units divided in a time division multiplexing and/or frequency division multiplexing manner; accordingly, in one resource period, the D2D signal is transmitted in a plurality of resource units, and the plurality of resource units are distributed discretely in the time domain and/or the frequency domain according to a preset rule.

Wherein the frequency domain discrete distribution is discontinuous in frequency positions occupied by the plurality of resource units; the time domain discrete distribution is discontinuous in time domain positions occupied by the plurality of resource units; the frequency domain and the time domain are distributed discretely, so that the frequency domain positions and the time positions occupied by the resource units are discontinuous.

The preset rule is as follows: the frequency domain position interval of two adjacent resource units in the plurality of resource units for transmitting the D2D signal is K/2; or, the frequency domain position intervals of two adjacent resource units in the plurality of resource units for transmitting the D2D signal are K/m;

The preset rule is as follows: the time domain position interval of two adjacent resource units in the plurality of resource units for transmitting the D2D signal is L/2;

Preferably, the resource units in a resource cycle are grouped in the time domain according to the number of dedicated resource units in the resource cycle, and the number of available resource units in the time domain in each resource group is the same as the number of dedicated resource units for D2D signal transmission; the resource elements are used for D2D signaling.

Preferably, the method further comprises: determining a location of a particular resource unit of a plurality of resource units used to transmit the D2D signal; determining the positions of other resource units according to the position of the specific resource unit and the preset rule; detecting the D2D signal in the particular resource and the other resource elements.

Determining the positions of other resource units in the plurality of resource units for transmitting the D2D signal according to the position (l, k) of the specific resource unit and the preset rule, wherein the specific resource unit is the first resource unit in the resource cycle for transmitting the D2D signal;

and/or the presence of a gas in the gas,

wherein i is a positive integer less than or equal to m.

Method examples IV,

The various embodiments provided in the present invention are applicable to cellular wireless communication systems or networks. A common cellular wireless communication system may be based on CDMA (code division multiple access) technology, FDMA (frequency division multiple access) technology, OFDMA (Orthogonal-FDMA) technology, SC-FDMA (single carrier-FDMA), single carrier frequency division multiple access) technology, and the like. For example, the downlink (or referred to as the forward link) of a 3GPP (3rd generation partnership project) LTE (long term evolution)/LTE-a (LTE-Advanced long term evolution) cellular communication system is based on OFDMA technology and the uplink (or referred to as the reverse link) is based on SC-FDMA multiple access technology. It is possible in the future to support hybrid multiple access techniques on one link.

In the OFDMA/SC-FDMA system, a radio resource (radio resource) for communication is a two-dimensional form of time-frequency. For example, for the LTE/LTE-a system, the communication resources of the uplink and downlink are divided in the time direction by radio frame (radioframe), each radio frame (radioframe) has a length of 10ms, and includes 10 subframes (sub-frames) with a length of 1ms, and each subframe includes two slots (slots) with a length of 0.5ms, as shown in fig. 4. And each slot may include 6 or 7 OFDM or SC-FDM symbols depending on a configuration of a Cyclic Prefix (CP).

In the frequency direction, resources are divided in units of subcarriers (subcarriers), and specifically, in communication, the minimum unit of frequency domain resource allocation is RB (resource block) and corresponds to one PRB (physical RB) of a physical resource. One PRB includes 12 sub-carriers in the frequency domain, corresponding to one slot (slot) in the time domain. Two PRBs adjacent in the time domain within a subframe are called a PRB pair (PRBpair). The resource corresponding to one subcarrier on each OFDM/SC-FDM symbol is called a Resource Element (RE).

Fig. 5 is a schematic diagram of a network deployment of a cellular wireless communication system. The illustration may be a 3gpp LTE/LTE-a system, or other cellular wireless communication technology. In an access network of a cellular wireless communication system, a network device generally includes a number of base stations (referred to as node bs, nodebs, evolved node bs, enbs, or enhanced node bs, evolved node bs, enbs), and other network entities (networks) or network elements (networks). Alternatively, in general, the radio access network may also be referred to as a network side (E-UTRAN, evolved universal terrestrial radio access network) in 3 GPP.

The base station herein also includes a Low Power Node (LPN) in a network, such as a femto cell or a home base station (pico, Relay, femto, HeNB, or HomeeNB), and may also be referred to as a small cell (smallcell).

For simplicity of description, only 3 base stations 51 are shown in fig. 5. A base station provides a certain radio signal coverage area with which terminals (or user equipment 52, user equipment, UE, or device) within the coverage area can communicate wirelessly. The wireless signal coverage area of a base station may be divided into one or more cell cells or sector sectors based on some criteria, for example, three cells.

Device discovery is a key technology in D2D communication, i.e., UEs conducting D2D communication first need to implement mutual discovery, referred to herein as discovery of D2D communication or D2D discovery or device discovery. Herein, device discovery is achieved by transmission and detection of a discovery signal (discovery signal) between user equipments. In the described embodiments of the present invention, the discovery signal includes a message (message) portion, and the load (payload) of the discovery signal carried by the message portion may affect the performance of device discovery. For example, a larger load may result in an increased code rate of the discovery signal and thus may result in a reduced discovery performance.

When the discovery signal load is large, more resources may be allocated for discovery signal transmission to guarantee its performance. For convenience of description, hereinafter, we define resource units (resource units) of device-to-device communication, each resource unit including 1 or more PRBs. For example, one resource unit may include 1 PRB pair, or 2 PRB pairs. Comprising 2 PRB pairs, the 2 PRB pairs may be consecutive in the time domain or consecutive in the frequency domain. When there are only 1 PRB pair in the resource unit, the meaning of the resource unit and PRB pair is identical.

In the scenario shown in fig. 5, the UE-side operation flow of the D2D communication method in this embodiment may include: a User Equipment (UE) receives a D2D resource configuration message and determines resources for D2D signal transmission according to the configuration message; the UE transmits a D2D signal in the resource.

Wherein the configuration message is at least used for indicating a resource set for transmitting the D2D signal, the device-to-device resource set has resource periods, and resources in each period are divided into resource units in a time division multiplexing and/or frequency division multiplexing manner.

For example, a network device (e.g., a base station) sends a configuration message indicating a set of resources for transmitting D2D signals, and a user equipment receives the configuration message.

The configuration message may be a higher layer signaling, such as a common RRC (radio resource control) signaling, and the network device sends the signaling in a broadcast form, for example, it may be carried in a system message block (SIB); or dedicated RRC signaling, which is sent by the network device to the user equipment.

Preferably, the device-to-device resource set indicated by the D2D resource configuration message has a periodicity, and the resource set configured by the configuration message may be a resource lasting for a plurality of periodicities. In one resource period, the resources are divided into resource units in a time division multiplexing and/or frequency division multiplexing manner (the definition of the resource units is described in the foregoing). The resource period configuration may be a period, e.g., 320ms (milliseconds, or 320 subframes), or 640ms, etc., of the set of resources indicated by the configuration message. The configuration message may indicate both the time and frequency location of the device-to-device resource within the resource period. For example, indicating specific subframes (such as uplink subframes) within the resource period as device-to-device resources, these subframes configured for D2D may be continuous or discretely distributed; while indicating the frequency location, for example, in a carrier (carrier) of an LTE/LTE-a system having a bandwidth of 10MHz, the effective bandwidth of the frequency domain is 50 PRBs, in which a partial bandwidth can be allocated for D2D.

Fig. 6 is an example of a D2D resource configuration. The allocated resources are used for device discovery, the resource period is 1280ms (128 wireless frames), 8 subframes are allocated in each resource period as time domain resources for device discovery, and the 8 subframes are continuous; the middle 40 PRBs of the frequency band are allocated in each subframe for device discovery, and these time domain 8 subframes and frequency domain 40 RBs are device discovery resources in one resource period of the resource set.

Preferably, the device-to-device resources within the device-to-device resource set period in the D2D resource configuration message include P resource groups in the time domain, P being an integer and P >1, each of the resource groups including therein time-domain consecutive subframes for the device-to-device communication; the resource groups in the resource period are distributed discretely, and the number of the subframes in different resource groups is the same in one resource period. By grouping the resources, cellular communication can be performed in subframes between the groups, avoiding that cellular communication is blocked due to long-time occupation of time domain resources by the device to the device.

Further, the number of time domain consecutive subframes used for the device-to-device communication within the packet is not greater than a length of an uplink Semi-persistent scheduling (SPS) interval (interval), which is a minimum value of SPS intervals allowed by the cellular communication system. E.g., the minimum value is 10ms, then the number of time domain consecutive subframes within the packet for the device-to-device communication is no greater than 10. I.e. the number of allocated consecutive subframes is defined in the system to be no more than 10. May be specifically defined as 10, or 9, or 8, or 4, or 2, etc.

Further, the number of time domain consecutive subframes within the packet for the device-to-device communication is not greater than an uplink hybrid automatic repeat request (HARQ) Round Trip Time (RTT). For example in an FDD cellular system, the harq rtt for the LTE/LTE-a uplink is 8ms, then the number of time domain consecutive subframes within the packet for the device-to-device communication is no greater than 8. I.e. it is defined in the system that the number of consecutive subframes allocated is not more than 8. May be specifically defined as 8, or 6, or 4, or 2, etc.

By limiting the number of consecutive device-to-device communication subframes in the packet as described above, it is possible to avoid the impact of D2D on cellular traffic, e.g., being limited to be no more than the SPS interval, and it is possible to ensure that the cellular uplink SPS transmissions of some UEs blocked by D2D are no more than 1 time; limited to no more than HARQ rtt, it can be guaranteed that the retransmission of the cellular link uplink HARQ process (process) blocked by D2D is no more than 1 time.

Further, it can also be defined that "not greater than" is "less than" as described above, i.e., the number of time domain consecutive subframes within the packet for the device-to-device communication is less than the uplink SPS interval or less than the harq rtt. And will not be described in detail.

Further, in the TDD cellular communication system, the number of time domain consecutive subframes used for the device-to-device communication within the packet is not greater than the number of consecutive uplink subframes in a TDD subframe uplink and downlink configuration (UL-dl configuration). The subframe uplink and downlink configuration of the TDDLTE/LTE-a system is shown in table 1.

Table 1: uplink and downlink configuration of LTE/LTE-ATDD system subframe

The uplink and downlink configuration of the TDD subframe may be the uplink and downlink configuration 0 or the uplink and downlink configuration 1, where the number of consecutive D2D communication subframes is not greater than 3. Or based on the uplink and downlink configuration of the currently used subframe, for example, the uplink and downlink configuration of the subframe used by the current cellular system is configuration 1, then the number of consecutive D2D communication subframes is not greater than 2.

Fig. 7 is another example of a D2D resource configuration. The allocated resources are also used for device discovery, and a resource period of the allocated resources is 5120ms (512 radio frames), 32 subframes are allocated in each resource period as device discovery time domain resources, the 32 subframes are not continuous, for example, in this example, 32 subframes are divided into 4 groups, each group has 8 subframes which are continuous, and the 4 groups of subframes are discretely distributed in one resource period. The allocation of frequency domain resources may be similar to the example described above. The shaded radio frames in the figure include discovery subframes. It should be noted that only one group of consecutive discovery subframes is shown in the figure, and the other groups are similar.

It should be noted that the above numbers and the distribution of the D2D resource sets in the resource cycle are only examples, and do not limit the relevant schemes. For example, the consecutive device discovery subframes described in the related examples are located in one radio frame, and do not represent that only this configuration can be supported, e.g., the device discovery subframes may be consecutive across radio frames.

In yet another embodiment, the device-to-device resources within the device-to-device resource set resource period comprise P resource groups in the time domain, P being an integer and P >1, each of said resource groups comprising a number of subframes therein for said device-to-device communication; the resource groups in the resource period are distributed discretely, and the number of the subframes in different resource groups is the same in one resource period. By grouping the resources, cellular communication can be performed in subframes between the groups, avoiding that cellular communication is blocked due to long-time occupation of time domain resources by the device to the device.

Further, a time domain span of a subframe within the packet for the device-to-device communication is not greater than a length of an uplink Semi-persistent scheduling (SPS) interval (interval), which is a minimum value of SPS intervals allowed by a cellular communication system. E.g., the minimum value is 10ms, then the time domain span of the subframes within the packet used for the device-to-device communication is no greater than 10 subframes. May be specifically defined as 10, or 9, or 8, or 4, or 2, etc.

Further, or, a time domain span of subframes for the device-to-device communication within the packet is not greater than an uplink hybrid automatic repeat request (HARQ) Round Trip Time (RTT). For example, in a TDD cellular system, the harq rtt for the LTE/LTE-a uplink is determined by a specific subframe uplink and downlink configuration, for example, if the harq rtt in some subframe uplink and downlink configurations is 10ms, then the time domain span of the subframe for the device-to-device communication in the packet is not greater than 10 subframes. May be specifically defined as 8, or 6, or 4, or 2, etc.

By limiting the number of consecutive device-to-device communication subframes within a packet as described above, the impact of D2D on cellular traffic, particularly in TDD cellular systems, can be avoided. E.g., defined as no greater than the SPS interval, may guarantee that the cellular link uplink SPS transmissions of certain UEs blocked by D2D are no greater than 1 time; limited to no more than HARQ rtt, it can be guaranteed that the retransmission of the cellular link uplink HARQ process (process) blocked by D2D is no more than 1 time.

Further, a time domain span of subframes within the packet for the device-to-device communication is not greater than a length of S radio frames, S > -1. For example, the time domain span of the sub-frames within the packet for the device-to-device communication may be defined to be no more than 1 radio frame, i.e., S ═ 1. And will not be described in detail.

It should be noted that, in the related description, the device-to-device communication refers to transmission of D2D signals or channels between terminals, and includes, but is not limited to, device-to-device discovery signals/channels, device-to-device control signaling/scheduling assignment signaling or channels carrying the signaling, device-to-device traffic data or channels carrying the data, and so on.

In one embodiment, the D2D signal of the user equipment is transmitted in a plurality of resource units and the plurality of resource units are distributed discretely in the time domain and/or the frequency domain within one resource period. The plurality of resource units used for transmitting the D2D signal are distributed discretely in a time domain and/or a frequency domain, and comprise at least one of the following: the frequency domain discrete distribution refers to discontinuous frequency positions occupied by the plurality of resource units; the time domain discrete distribution refers to discontinuous time domain positions occupied by the plurality of resource units; the frequency domain and the time domain are discretely distributed, which means that the frequency domain positions and the time positions occupied by the plurality of resource units are discontinuous. In other words, when the D2D signal of the user equipment is transmitted in a plurality of resource elements and the plurality of resource elements are discretely distributed in the frequency domain, the time domain positions of the plurality of resource elements are continuous; when the D2D signal of the user equipment is transmitted in a plurality of resource units and the plurality of resource units are distributed discretely in the time domain, the frequency domain positions of the plurality of resource units are continuous; when the D2D signal of the user equipment is transmitted in a plurality of resource units and the plurality of resource units are distributed discretely in time domain and frequency domain, the frequency domain positions and the time domain positions of the plurality of resource units are not continuous.

In one embodiment, adjacent two of the plurality of resource elements used for transmitting the D2D signal have a frequency domain location interval of K/2; where K is the number of frequency domain available resource units for device-to-device communication. The two adjacent resource units refer to two resource units with a nearest distance in any time domain position in the plurality of resource units. If the plurality of resource units includes only 2 resource units, the two adjacent resource units refer to the 2 resource units.

In one embodiment, adjacent two of the plurality of resource elements used for transmitting the D2D signal have a frequency domain location interval of K/m; where K is the number of available resource units in the frequency domain for device-to-device communication, and m is the number of resource units used for transmitting the D2D signal in one resource cycle.

In one embodiment, the time domain position interval of two adjacent resource units of the plurality of resource units for transmitting the D2D signal is L/2; where L is the number of time domain available resource units in a resource cycle used for device-to-device communication.

Fig. 8 shows a specific example. In this example, the D2D signal for a particular user equipment is transmitted in 2 resource elements during one resource period. Each resource unit is the same size as one PRB pair. In this example, for simplicity of description, it is assumed that K is 8 and L is 6, that is, there are 48 resource units in a resource period. For a particular UE, its D2D signal is transmitted in 2 resource elements within one resource period; the frequency interval of the 2 resource units is K/2-4, and the time positions are the same.

Fig. 9 shows a specific example. In this example, the D2D signal for a particular user equipment is transmitted in 2 resource elements during one resource period. Each resource unit is the same size as one PRB pair. In this example, for simplicity of description, it is also assumed that K is 8 and L is 6, that is, there are 48 resource units in a resource period. For a particular UE, its D2D signal is transmitted in 2 resource elements within one resource period; the time interval of the 2 resource units is L/2-3, and the frequency positions are the same.

Fig. 10 shows a specific example. In this example, the D2D signal for a particular user equipment is transmitted in 2 resource elements during one resource period. Each resource unit is the same size as one PRB pair. In this example, for simplicity of description, it is also assumed that K is 8 and L is 6, that is, there are 48 resource units in a resource period. For a particular UE, its D2D signal is transmitted in 2 resource elements within one resource period; the frequency interval of the 2 resource units is K/2-4, and the time interval is L/2-3.

Fig. 11 shows another embodiment. In this example, the size of the resource unit is the bandwidth of 2 consecutive PRBs in the frequency domain, and the time domain is 1 PRB pair, i.e., 1 subframe. In other words, 1 resource element includes 2 PRB pairs that are consecutive in the frequency domain. In this example, for simplicity of description, it is assumed that K is 4 and L is 4, that is, there are 16 resource units in a resource period. For a particular UE, its D2D signal is transmitted in 2 resource elements within one resource period; the frequency interval of the 2 resource units is K/2-4, and the time interval is L/2-3. Note that one square in the figure represents 1 PRB pair. Similarly to the examples in fig. 9 and fig. 10, the 2 resource units may be discontinuous only in the frequency domain or only in the time domain, and are not described again.

Fig. 12 shows a specific example. In this example, the D2D signal for a particular user equipment is transmitted in 2 resource elements during one resource period. The size of each resource unit is NUM PRB pairs with continuous frequency domains, and NUM is more than or equal to 1. In this example, for simplicity of description, it is also assumed that K is 8 and L is 6, that is, there are 48 resource units in a resource period. For a particular UE, its D2D signal is transmitted in 2 resource elements within one resource period; the frequency interval of the 2 resource units is K/2-4, and is continuous in time.

In one embodiment, the time domain position interval of two adjacent resource units in the plurality of resource units for transmitting the D2D signal is L/n; wherein L is the number of time domain available resource units in a resource period for device-to-device communication, and n is the number of resource units used for transmitting the D2D signal in one resource period.

Fig. 13 shows a specific example. In this example, the D2D signal for a particular user equipment is transmitted in 4 resource elements during one resource period. Each resource unit is the same size as one PRB pair. In this example, for simplicity of description, it is assumed that K is 8 and L is 12, that is, 96 resource units are in total in one resource period. For a particular UE, its D2D signal is transmitted in 4 resource elements in one resource period; in the 4 resource units, the frequency interval between two adjacent resource units is K/2-4, and the time interval is L/4-3. As mentioned above, the two adjacent resource units refer to two of the plurality of resource units that are closest in time domain position. For example, in this example, 1 and 2 are adjacent resource units, 2 and 3 are adjacent resource units, and 3 and 4 are adjacent resource units. The meaning of adjacent resource units in the relevant embodiments is similar.

Fig. 14 shows another embodiment. Unlike fig. 13, in this example, the frequency interval of 4 resource elements for D2D signaling for a particular UE is K/4-2 and the time interval is L/4-3.

Fig. 15 shows yet another embodiment. Unlike fig. 14 in this example, the 4 resource elements for D2D signaling for a particular UE are contiguous in the time domain.

It should be noted that the present example is also applicable to the case where the size of the resource unit is more than 1 PRB pair. For example, 1 resource unit includes 2 PRB pairs that are consecutive in the frequency domain, and in this case, the resource unit represented by the small squares in fig. 13 and 12 includes 2 PRB pairs.

In one embodiment, the plurality of resource elements used for transmitting the D2D signal have a time domain position interval of L1/n; where L1 is the number of time domain available resource units per resource grouping within a resource period for device-to-device communication, and n is the number of resource units used for transmitting the D2D signal within one resource period. Assuming that the time length of a resource unit is the same as a PRB pair (length of 1 subframe), the number of subframes of the device-to-device resource set configured in each resource period is 32, but in the time domain, it corresponds to 4 resource groups, each resource group includes 8 device-to-device subframes, i.e. L1 equals 8, and assuming that the number of resource units transmitting the D2D signal in one resource period is 2, i.e. n equals 2, the time interval of the multiple resource units is 4, i.e. 4 subframes or resource units are separated. In this example, it can be further defined that for a particular UE, the 2 resource elements that transmit its D2D signal do not span the resource grouping, i.e., they are within 1 resource grouping.

For example, the correlation scheme is still applicable when the time domain resources in the examples shown in fig. 8-15 are defined as resources for each resource grouping within a resource period. And will not be described in detail.

In one embodiment, the resource units within a resource period are grouped in the time domain according to the number of dedicated resource units for the D2D signaling within the resource period, the number of time domain available resource units within each resource group being the same as the number of dedicated resource units for the D2D signaling; the D2D signal is transmitted within one of the resource packets. That is, assuming that the number of resource units for transmitting the D2D signal in one resource period is n, the number of time domain resource units in each resource packet is n; the dedicated resource units transmitting the D2D signal are located within one resource packet.

Fig. 16 shows a specific example. In this example, the D2D signal for a particular user equipment is transmitted in 2 resource units (i.e., n-2) within one resource period. The size of each resource unit is NUM PRB pairs with continuous frequency domains, and NUM is more than or equal to 1. In this example, for simplicity of description, K is 8 and L is 6. The resource elements in the resource period are grouped in the time domain according to the number of the dedicated resource elements in one resource period for the D2D signal transmission, i.e., the resources are grouped according to n-2 in this example, the number of the time domain resource elements in each group is n, i.e., each group includes 2 consecutive subframes in this example. For a specific UE, in one resource period, the D2D signal is transmitted only in one resource packet, i.e. in 2 resource units in one resource packet in this example; for the 2 resource units, the frequency interval is K/2-4, which is continuous in time.

Fig. 17 shows another specific example. In this example, the D2D signal for a particular user equipment is transmitted in 4 resource units (i.e., n-4) within one resource period. The size of each resource unit is NUM PRB pairs with continuous frequency domains, and NUM is more than or equal to 1. In this example, for simplicity of description, K is 8 and L is 12. The resource units in the resource period are grouped in the time domain according to the number of the dedicated resource units used for the D2D signal transmission in one resource period, i.e., the resources are grouped according to n-4 in this example, the number of the time domain resource units in each group is n, i.e., each group includes 4 consecutive subframes in this example, since the time length of each resource unit is the same as 1 subframe, i.e., the number of the time domain resource units in each group is 4. For a specific UE, in one resource period, its D2D signal is transmitted in only 4 resource units in one resource packet; for the 4 resource units, the frequency interval is K/n-2, and the resource units are consecutive in time.

Fig. 18 shows yet another specific example. In this example, the frequency spacing for a particular UE to transmit the D2D signal is determined in a manner K/2, and the rest is the same as described in the previous example.

It should be noted that when grouping the D2D resources in a resource period, if the number of time domain resource units cannot be divided by the number of resource units occupied by a specific D2D signal transmission, the number of time domain resource units in the 1 st or last resource group in the resource period may be smaller than the number of time domain resource units in other groups.

In one embodiment, the D2D signal in the relevant example is a discovery signal for device discovery or a physical channel carrying a discovery signal.

In one embodiment, the D2D signal in the relevant example is a signal used for device-to-device communication control signaling or scheduling assignment information transmission or a physical channel carrying the signal.

In one embodiment, in one resource period, the D2D signal transmitted by the ue occupies multiple resource units, and the information transmitted in the multiple resource units is the same or different. The same means that the information transmitted in the plurality of resource units is the repeated transmission of a set of valid information; the same or different modulation coding scheme and coding redundancy version can be used in the repeated transmission. For example, the discovery signal or the control signaling (alternatively referred to as scheduling assignment) is repeatedly transmitted a plurality of times within one resource period. By contrast, the information transmitted in the resource units constitutes a complete information, such as a complete discovery signal message.

In one embodiment, the user equipment determines the resource location for its transmission of the D2D signal by determining the location of a particular resource unit of a plurality of resource units used for transmission of the D2D signal, the locations of other resource units of the plurality of resource units being determined according to agreed rules. The agreed rule is the manner of discrete distribution of the plurality of resource units as described above.

For example, if there are 2 resource units used by the UE to transmit a D2D signal in one resource period and the position of a specific resource unit is (L, k), the time position of the second resource unit used by the UE to transmit the D2D signal may be mod (L + L/2, L), or mod (L + L1/2, L1), or L + 1; the frequency location of the second resource unit may be mod (K + K/2, K), or K.

For example, if there are m resource units and the position of a specific resource unit is (L, k) in one resource period for the UE to transmit the D2D signal (assuming that the specific resource unit is represented as the first resource unit), the time position of the i-th resource unit for the UE to transmit the D2D signal may be mod (L + (i-1) L/m, L), or mod (L + (i-1) L1/m, L1), or L + i-1; the frequency location of the ith resource unit may be mod (K + (i-1) × K/m, K), or mod (K + mod (i-1, 2) × K/2, K), or K. Wherein i is a positive integer less than or equal to m.

The values of L and K are respectively the frequency and time domain position of the user equipment in a specific resource unit in a resource period, the value of L is 0-L-1, or 0-L1-1, and the value of K is 0-K. mod denotes a modulo operation, such as mod (5,2) 1. The remaining letters have the same meaning as previously described.

Further, the specific way of determining the location of the first resource unit may be UE random selection, that is, the UE randomly selects a resource location for transmission of a specific resource unit in the candidate resource unit set. The set of candidate resource elements may be a set of device-to-device resource elements within one device-to-device resource period, e.g., the UE may randomly select among L × K resource elements; or the candidate resource unit set may be the number of D2D signals that can be accommodated within one device-to-device resource period, e.g., each D2D signal is transmitted in m resource units, then randomly selecting among the candidate resource unit set means randomly selecting among L × K/m resource units; or the candidate resource unit set may be a set of a device-to-device resource unit grouping within a device-to-device resource cycle, e.g., randomly selected among L1 × K resource units; or, similar to the above, randomly selected among L1 × K/m resource elements. Wherein m is the number of resource units for transmitting the D2D signal in one resource period, and the remaining letters have the same meanings as above. Alternatively, the candidate resource unit set is all resource units whose time domain positions l of the resource units in the resource period satisfy mod (l, m) ═ 0.

Further, the user equipment may determine the location of the first resource unit according to an indication of a network device (e.g., a base station). For example, a second resource configuration message is transmitted by the base station to the user equipment, the second resource configuration message indicating a time and frequency location of a first resource unit of the user equipment transmitting the D2D signal within one resource period. The second resource configuration message may be user equipment specific RRC signaling or physical layer signaling.

In an embodiment, the second resource configuration message sent by the base station to the user equipment includes a time domain resource indication parameter and a frequency domain resource indication parameter, where the time domain resource indication parameter and the frequency domain resource indication parameter indicate, to the user equipment, a location of a specific resource unit, such as a location of a first resource unit, in a plurality of resource units in one resource period for transmitting the D2D signal.

Further, the frequency domain resource is indicated by an index. For example, the frequency domain location of the particular resource unit is indicated by an index of 0, 1, 2, …, Kf-1 or 1, 2, …, Kf. Where Kf is the total number of available resource units (i.e., the number of D2D resources allocated in the resource period) of the D2D signal in the frequency domain. Or Kf is the total number of resource units in the frequency domain, for example, in the LTE system, when the system bandwidth is 10MHz, the total number of resource blocks in the frequency domain is 50, the total number of resource units is 50/Mu, and Mu is the frequency domain bandwidth of one D2D resource unit, and is expressed in units of resource blocks. When 50/Mu is a non-integer, it is rounded up or down or up.

Or, the frequency domain resource is indicated by a bitmap (bitmap) form. For example, the frequency domain position of the specific resource unit is indicated by a bitmap with length Kf. Wherein Kf has the same meaning as described above.

Further, the time domain resource is indicated by an index. For example, then the time domain location of the particular resource element is indicated by an index of 0, 1, 2, …, Kt-1 or 1, 2, …, Kt. Where Kt is the total number of available resource units in the resource period for the time domain D2D signal (i.e., the number of D2D resources configured in the resource period, if the time span of a resource unit is 1 subframe, then the number of D2D subframes in the resource period). Or Kt is the maximum number of resource units in the time domain allowed in the resource period, for example, in the lte fdd system, in each D2D discovery period, if a maximum of 200 discovery subframes can be configured, Kt is 200, regardless of the number of actually configured D2D discovery subframes.

Alternatively, the time domain location of the particular resource unit is indicated by an index of 0, 1, 2, …, Kt/m-1 or 1, 2, …, Kt/m. Wherein m is the number of resource units of D2D occupied by the transmission of the D2D signal in one resource period, for example, when the D2D signal is repeatedly transmitted in a resource period, m represents the number of times of repeated transmission, and the meanings of the other parameters are the same as those described above. When Kt/m is a non-integer, it is rounded up or rounded down or rounded up.

In one embodiment, the user equipment determines the resource location for transmitting the D2D signal by determining the location of a virtual resource for transmitting the D2D signal and determining the locations of a plurality of physical resource units for transmitting the D2D signal based on the mapping relationship between the virtual resource and the physical resource.

For example, the number of D2D signal resources in a resource cycle is L × K in terms of resource units, and the corresponding number of virtual resources is assumed to be L × K/m. Where m is the number of resource units occupied by the specific ue transmitting the D2D signal in one resource period, and the remaining letters have the same meanings as described above. Meanwhile, the virtual resource and the physical resource unit have an agreed mapping relation. For example, the mapping is such that the virtual resource location (or number) corresponds to one of the resource units, such as the first one, used for one D2D signaling. The locations of the remaining resource units are determined according to the rules agreed between the plurality of resource units.

Further, the specific way of determining the location (or number) of the virtual resource may be UE random selection, that is, the UE randomly selects a location (or number) of a virtual resource in the virtual resource unit candidate set. The virtual resource unit candidate set may be a set corresponding to a resource unit in one resource cycle in the resource set, for example, the UE may randomly select from L × K/m virtual resources; or a corresponding set of device-to-device resource element groups within a device-to-device resource cycle, for example randomly selected among L1 × K/m virtual resources. Wherein m is the number of resource units for transmitting the D2D signal in one resource period, and the remaining letters have the same meanings as above.

Further, the user equipment may determine the location (or number) of the virtual resource according to an indication of a network device (e.g., a base station). For example, a second resource configuration message indicating a location (or number) of a virtual resource where the user equipment transmits the D2D signal within one resource period is transmitted to the user equipment by the base station. The second resource configuration message may be user equipment specific RRC signaling or physical layer signaling.

The first embodiment of the device,

In the present embodiment, a D2D communication system is provided. Fig. 19 is a schematic structural diagram of a wireless communication system according to an embodiment of the present invention, the wireless communication system according to the embodiment of the present invention including: a network side device 1902 of a cellular network, a first user equipment 1904 and a second user equipment 1906. The above-described entities will be described separately below.

In one embodiment, a network side device 1902 of a cellular network may be used to perform configuration of device discovery resources.

As shown in fig. 20, the network-side device 1902 may include at least:

a configuration module 2002 for generating a D2D first resource configuration message;

a sending module 2004 for sending the D2D first resource configuration message to a D2D user equipment, UE.

The configuration module 2002 is specifically configured to configure device-to-device radio resources and generate a corresponding configuration message.

Wherein the first resource configuration message comprises a set of resources for allocating D2D, the set of resources for transmission of device-to-device signals; the resource set is periodically distributed, and each resource period comprises a plurality of resource units which are divided in a time division multiplexing and/or frequency division multiplexing mode; the set of resources is for the D2D user device to transmit D2D signals.

For example, the device discovery resources may be configured in a resource cycle manner, the device discovery radio resources in each resource cycle are divided into discovery resource units in a time division multiplexing and/or frequency division multiplexing manner, and each discovery signal may be transmitted on one discovery resource unit.

In an embodiment, the network-side device 1902 may be a base station (base station or eNB), or other network access device such as a small cell, or may be a network node of an upper layer, such as a gateway (gateway), or a Mobility Management Entity (MME), or other server or network unit that provides services for D2D, or may include one or more of the above nodes.

In one embodiment, the network-side device 1902 may also be a temporarily deployed network element in an uncovered scenario. The non-coverage scene refers to a scene that the user equipment is in a coverage hole of the cellular network, such as a damaged cellular infrastructure, or a coverage hole area.

In an embodiment, the network side device 1902 may also be a UE acting as a cluster head (ClusterHead) or a primary UE (primaryue), for example, in some specific scenarios, such as scenarios without network coverage, a specific user equipment performs configuration of device discovery resources.

The discrete distribution mode comprises at least one of the following modes: the frequency locations of the plurality of resource units are not contiguous; a temporal location of the plurality of resource units is discontinuous; the frequency location and the time location of the plurality of resource units are not contiguous.

The preset rule is as follows: the frequency domain position interval of two adjacent resource units in the plurality of resource units for transmitting the D2D signal is K/2; or, the frequency domain position intervals of two adjacent resource units in the plurality of resource units for transmitting the D2D signal are K/m; wherein K is the number of available resource units in the frequency domain for device-to-device communication, and m is the number of resource units used for transmitting the D2D signal in one resource cycle.

The sending module is further configured to send a D2D second resource configuration message; wherein the second resource configuration message comprises a location indicating a first one of a plurality of resource elements transmitting the D2D signal; alternatively, in an embodiment, indicating the location of the virtual resource, which has a preset mapping relationship with the plurality of resource units for transmitting the D2D signal, the first user equipment 1904 may include as shown in fig. 21:

a first communication unit 2102 for receiving a D2D first resource configuration message from a network node,

a baseband processing unit 2104 for determining a set of resources for allocating D2D according to the first resource configuration message;

a second communication unit 2106 for transmitting signals of the device-to-device communication within the set of D2D resources; wherein the set of resources is for transmission of device-to-device signals; the resource sets are periodically distributed, and each resource period comprises a plurality of resource units which are divided in a time division multiplexing and/or frequency division multiplexing mode.

Preferably, a second communication unit 2106, configured to send the D2D signal in the dedicated resource unit; accordingly, the baseband processing unit 2104 is further configured to determine, from the set of resources, a location of a dedicated resource unit for transmitting the D2D signal.

In one embodiment, the second user device 1906 may detect the D2D signal.

In one embodiment, the discrete distribution of the plurality of resource units for transmitting the D2D signal in the time domain and/or the frequency domain includes at least one of: the frequency domain discrete distribution refers to discontinuous frequency positions occupied by the plurality of resource units; the time domain discrete distribution refers to discontinuous time domain positions occupied by the plurality of resource units; the frequency domain and the time domain are discretely distributed, which means that the frequency domain positions and the time positions occupied by the plurality of resource units are discontinuous.

The baseband processing unit is specifically configured to determine a location of a virtual resource used for transmitting the D2D signal, and determine locations of a plurality of resource units used for transmitting the D2D signal as locations of the dedicated resource units according to the location of the virtual resource.

The baseband processing unit is specifically configured to randomly select a position of the virtual resource unit from a virtual resource candidate set; alternatively, a second resource configuration message is received D2D from the network node through the first communication unit, wherein the second resource configuration message is at least for indicating a location of the virtual resource.

The baseband processing unit is specifically configured to determine a location of a specific resource unit of the multiple resource units for transmitting the D2D signal, determine locations of other resource units of the multiple resource units for transmitting the D2D signal according to the location of the specific resource unit and the preset rule, and use the location of the specific resource unit and the locations of the other resource units as the locations of the dedicated resources.

The baseband processing unit is specifically configured to randomly select a position of the specific resource unit in the resource unit candidate set; alternatively, a device-to-device second resource configuration message is received from the network node via the first communication unit, the second resource configuration message indicating at least a location of the particular resource unit.

The preset rule is as follows: the frequency domain position interval of two adjacent resource units in the plurality of resource units for transmitting the D2D signal is K/2; or, the frequency domain position intervals of two adjacent resource units in the plurality of resource units for transmitting the D2D signal are K/m; wherein, K is the number of available resource units in the frequency domain for the device-to-device communication, and m is the number of resource units used for transmitting the D2D signal in one resource cycle.

The preset rule is as follows: the time domain position interval of two adjacent resource units in the plurality of resource units for transmitting the D2D signal is L/2; or, the time domain position interval of two adjacent resource units in the plurality of resource units for transmitting the D2D signal is L/n; or, the time domain position interval of two adjacent resource units in the plurality of resource units for transmitting the D2D signal is L1/2; or, the time domain position interval of two adjacent resource units in the plurality of resource units for transmitting the D2D signal is L1/n; wherein L is the number of time domain available resource units in a resource period for the device-to-device communication, L1 is the number of time domain available resource units per resource group in a resource period for the device-to-device communication, and n is the number of dedicated resource units for the D2D signaling in one resource period.

The D2D signal is a discovery signal for device discovery or a physical channel carrying a discovery signal; or, the D2D signal is a signal used for control signaling of device communication, or scheduling assignment information transmission, or a physical channel carrying the signal.

The resource unit in the resource cycle comprises a plurality of resource groups in the time domain; each of the resource packets includes time-domain contiguous subframes for transmission of signals for the device-to-device communication; the resource groups are distributed discretely and the number of the subframes in different resource groups is the same in one resource period.

In one embodiment, the user equipment determines the resource location for its transmission of the D2D signal by determining the location of a first resource unit of a plurality of resource units for transmission of the D2D signal, the locations of other resource units of the plurality of resource units being determined according to agreed rules. The rules of the convention are as previously described.

Further, the specific manner of determining the location (or number) of the virtual resource or the first resource unit may be that the baseband processing unit randomly selects, that is, the baseband processing unit randomly selects the location (or number) of one virtual resource, or randomly selects the location of the first resource unit.

Further, the baseband processing unit may determine the location (or number) of the virtual resource according to an indication of a network device (e.g., a base station), or determine the location of the first resource unit according to the indication. For example, the first communication unit receives a second resource configuration message transmitted by the base station to the user equipment, the second resource configuration message indicating a location (or number) of a virtual resource for the user equipment to transmit a D2D signal within one resource period, or indicating a location of the first resource unit. The second resource configuration message may be user equipment specific RRC signaling or physical layer signaling.

In the following, the functions of the apparatus provided in the foregoing embodiment are described in detail, where the user equipment includes:

a baseband processing unit, configured to determine a resource for transmitting a D2D signal according to the first resource configuration message;

a second communication unit, configured to send a D2D signal on the resource.

Here, the first resource configuration message includes: indicating a set of resources to transmit the D2D signal;

the device-to-device resource set comprises resource periods, and each resource period comprises a plurality of resource units which are divided in a time division multiplexing and/or frequency division multiplexing mode.

The baseband processing unit is specifically configured to determine, according to the first resource configuration message, a location of a specified resource unit in a resource cycle for transmitting the D2D signal; the appointed resource units are a plurality of resource units distributed in a time domain and/or frequency domain discrete mode;

wherein the time domain and/or frequency domain discretization comprises at least one of:

the plurality of resource units occupy non-contiguous frequency locations;

the plurality of resource units occupy discontinuous time domain positions;

the plurality of resource units occupy discrete frequency domain locations and time locations.

The baseband processing unit is specifically configured to determine positions of virtual resources used for transmitting the D2D signal, and determine positions of a plurality of resource units used for transmitting the D2D signal according to the positions of the virtual resources in a preset mapping manner.

The second communication unit is specifically configured to send the D2D signal in a resource unit specified in one resource cycle.

The discontinuous frequency positions are: the frequency domain position interval of the resource units used for transmitting the D2D signal is K/2; or, the frequency domain position intervals of a plurality of resource units used for transmitting the D2D signal are K/m;

The discontinuous time domain positions are: the time domain position intervals of a plurality of resource units used for transmitting the D2D signal are L/2;

The D2D signal is a discovery signal for device discovery or a physical channel carrying a discovery signal; or,

the D2D signal is a signal used for control signaling for device-to-device communication, or scheduling assignment information transmission, or a physical channel carrying the signal.

The preset mapping mode is as follows: randomly selecting a location of the particular resource unit or a location of the virtual resource unit; or receiving a device-to-device second resource configuration message, and determining the location of the specific resource unit or the location of the virtual resource according to the second resource configuration message.

each of the resource packets includes time-domain contiguous subframes for the device-to-device communication;

The network node provided by the embodiment of the invention comprises:

The appointed resource units are a plurality of resource units distributed in a time domain and/or frequency domain discrete mode;

the plurality of resource units occupy non-contiguous frequency locations;

the plurality of resource units occupy discontinuous time domain positions;

the plurality of resource units occupy discrete frequency domain locations and time locations. .

The sending module is further configured to send a D2D second resource configuration message; wherein the second resource configuration message comprises a location indicating a first one of a plurality of resource elements transmitting the D2D signal; or indicating the position of the virtual resource, wherein the position of the virtual resource has a preset mapping relation with a plurality of resource units for transmitting the D2D signal.

Preferably, another user equipment provided in this embodiment may include:

a first communication module, configured to receive a configuration message of a D2D resource; wherein the configuration message comprises at least: indicating a set of resources for detecting the D2D signal, the set of device-to-device resources having a resource periodicity; each resource cycle comprises a plurality of resource units divided in a time division multiplexing and/or frequency division multiplexing mode; correspondingly, in one resource period, the D2D signal is transmitted in a plurality of resource units, and the plurality of resource units are distributed discretely in the time domain and/or the frequency domain;

a second communication module to detect a D2D signal in the set of resources.

The frequency domain discrete distribution is discontinuous in frequency positions occupied by the plurality of resource units;

The above description is only a preferred embodiment of the present invention, and is not intended to limit the scope of the present invention.

Claims

1. A device-to-device, D2D, communication method, the method comprising:

receiving a D2D first resource configuration message from a network node;

transmitting the device-to-D2D signal within the set of resources;

2. The method of claim 1, further comprising:

the discrete distribution mode comprises at least one of the following modes:

the frequency locations of the plurality of resource units are not contiguous;

a temporal location of the plurality of resource units is discontinuous;

3. The method of claim 2, wherein determining the location of a dedicated resource unit for transmitting the D2D signal comprises:

4. The method of claim 3, wherein determining the location of the virtual resource for transmitting the D2D signal comprises:

or,

5. The method of claim 1 or 2, wherein determining the location of the dedicated resource unit for transmitting the D2D signal comprises:

6. The method of claim 5, wherein determining the location of a particular resource unit of the plurality of resource units used for transmitting the D2D signal comprises:

or,

7. The method according to any one of claims 2 to 6, wherein the preset rule is: the frequency domain position interval of two adjacent resource units in the plurality of resource units for transmitting the D2D signal is K/2; or, the frequency domain position intervals of two adjacent resource units in the plurality of resource units for transmitting the D2D signal are K/m;

8. The method according to any one of claims 2 to 6, wherein the preset rule is: the time domain position interval of two adjacent resource units in the plurality of resource units for transmitting the D2D signal is L/2;

9. The method according to claim 1 or 8, characterized in that the method further comprises:

10. The method of claim 5, further comprising:

wherein i is a positive integer less than or equal to m.

11. The method according to any one of claims 1 to 6, wherein the D2D signal is a discovery signal for device discovery or a physical channel carrying a discovery signal; or,

12. The method of claim 1, wherein the resource unit in the resource period comprises a plurality of resource packets in time domain;

13. The method of claim 11, wherein the determining of the number of time-domain consecutive subframes comprises at least one of:

14. A D2D communication method, the method comprising:

generating a D2D first resource configuration message;

15. The method of claim 14, further comprising: sending a D2D second resource configuration message;

16. The method of claim 15,

the second resource configuration message comprises: a time domain resource indication parameter and a frequency domain resource indication parameter;

17. A D2D communication method, the method comprising:

receiving a configuration message for a D2D resource from a network node;

detecting a D2D signal in the set of resources;

18. The method of claim 17,

19. The method of claim 18, wherein the preset rule is: the frequency domain position interval of two adjacent resource units in the plurality of resource units for transmitting the D2D signal is K/2; or, the frequency domain position intervals of two adjacent resource units in the plurality of resource units for transmitting the D2D signal are K/m;

20. The method of claim 19, wherein the preset rule is: the time domain position interval of two adjacent resource units in the plurality of resource units for transmitting the D2D signal is L/2;

21. The method according to any one of claims 17 to 20,

grouping the resource units in the resource cycle in the time domain according to the number of the dedicated resource units in one resource cycle, wherein the number of the time domain available resource units in each resource group is the same as the number of the dedicated resource units for the D2D signal transmission;

the resource elements are used for D2D signaling.

22. The method of claim 17,

determining a location of a particular resource unit of a plurality of resource units used to transmit the D2D signal;

23. The method of claim 17 or 21,

and/or the presence of a gas in the gas,

wherein i is a positive integer less than or equal to m.

24. A user device, comprising:

25. The user equipment of claim 24,

the second communication unit is configured to transmit the D2D signal in the dedicated resource unit;

the discrete distribution mode comprises at least one of the following modes:

the frequency locations of the plurality of resource units are not contiguous;

a temporal location of the plurality of resource units is discontinuous;

26. The UE of claim 25, wherein the baseband processing unit is specifically configured to determine locations of virtual resources used for transmitting the D2D signal, and determine locations of multiple resource units used for transmitting the D2D signal as the locations of the dedicated resource units according to the locations of the virtual resources.

27. The user equipment of claim 26,

the baseband processing unit is specifically configured to randomly select a position of the virtual resource unit from a virtual resource candidate set;

or,

28. The user equipment of claim 25,

29. The user equipment of claim 28,

the baseband processing unit is specifically configured to randomly select a location of the specific resource unit from a resource unit candidate set;

or,

30. The ue of any one of claims 25 to 29, wherein the preset rule is: the frequency domain position interval of two adjacent resource units in the plurality of resource units for transmitting the D2D signal is K/2; or, the frequency domain position intervals of two adjacent resource units in the plurality of resource units for transmitting the D2D signal are K/m;

31. The ue of any one of claims 25 to 29, wherein the preset rule is: the time domain position interval of two adjacent resource units in the plurality of resource units for transmitting the D2D signal is L/2;

32. The UE of claim 24 or 31, wherein the baseband processing unit is further configured to group the resource units in a resource period in time domain according to the number of dedicated resource units in the resource period, so that the number of available resource units in time domain in each resource unit group is the same as the number of dedicated resource units for the D2D signal transmission;

33. The UE of claim 28, wherein the baseband processing unit is further configured to determine locations of other resource units in the plurality of resource units for transmitting the D2D signal according to the location (l, k) of the specific resource unit and the preset rule;

wherein i is a positive integer less than or equal to m.

34. The UE of any one of claims 25 to 29, wherein the D2D signal is a discovery signal for device discovery or a physical channel carrying a discovery signal; or,

35. The UE of claim 25, wherein the resource units in the resource period comprise a plurality of resource packets in time domain;

36. The UE of claim 35, wherein the determination of the number of consecutive subframes in the time domain comprises at least one of:

37. A network node, comprising:

38. The network node of claim 37, wherein the sending module is further configured to send a D2D second resource configuration message;

39. The network node of claim 38,

40. A user device, comprising:

a second communication module to detect a D2D signal in the set of resources.

41. The UE of claim 40, wherein the frequency domain discrete distribution is discontinuous in frequency locations occupied by the plurality of resource units;

42. The UE of claim 41, wherein the preset rule is: the frequency domain position interval of the resource units used for transmitting the D2D signal is K/2; or, the frequency domain position intervals of a plurality of resource units used for transmitting the D2D signal are K/m;

43. The UE of claim 42, wherein the preset rule is: the time domain position intervals of a plurality of resource units used for transmitting the D2D signal are L/2;

44. The user equipment of any one of claims 40 to 43, wherein:

the baseband processing module is specifically configured to group, in a time domain, the resource units in a resource cycle according to the number of dedicated resource units in the resource cycle, where the number of time-domain available resource units in each resource group is the same as the number of dedicated resource units used for the D2D signal transmission; the resource elements are used for D2D signaling.

45. The user equipment of claim 40,

the baseband processing module is specifically configured to determine a location of a specific resource unit in the plurality of resource units used for transmitting the D2D signal; determining the positions of other resource units in the plurality of resource units for transmitting the D2D signal according to the position of the specific resource unit and the preset rule; detecting the D2D signal in the particular resource and the other resource elements.

46. The user equipment of claim 40,

the baseband processing module is specifically configured to determine, according to a location (l, k) of the specific resource unit and the preset rule, locations of other resource units in the plurality of resource units for transmitting the D2D signal, where the specific resource unit is a first resource unit in the resource cycle for transmitting the D2D signal;

and/or the presence of a gas in the gas,

wherein i is a positive integer less than or equal to m.

47. A device-to-device communication system, the system comprising: