CN106375930A - Device-to-device (D2D) communication method and apparatus - Google Patents

Abstract

The invention discloses a device-to-device (D2D) communication method and apparatus. The D2D communication method comprises the following steps: first user equipment (UE) obtaining a first power value, wherein the first power value comprises a maximum standard power value of the first UE for sending data; the first UE obtaining a second power value, wherein the second power value comprises a power value for D2D communication between the first UE and the second UE; and the first UE comparing the first power value and the second power value with a third power value, determining that minimum power is output power used for sending the data to the second UE by the first UE, and the third power value comprises a maximum emission power value of the first UE. According to the invention, the output power used for sending the data to the second UE by the first UE is determined, and under the condition that D2D communication performance is not affected, it is ensured that interference power of the first UE for a base station does not go beyond a first target power value configured for an RRC signaling of the base station.

Description

Device-to-device communication method and device

Technical Field

The present invention relates to internet technologies, and in particular, to a device-to-device communication method and apparatus.

Background

With the diversification and development of mobile communication services, Device-to-Device (D2D) communication is receiving much attention. D2D communication may also be referred to as Proximity Service (ProSe), that is, a first User Equipment (User Equipment, UE for short) and a second UE located in the same cell directly perform data communication through an air interface, without forwarding through a base station and a core network.

In the prior art, when a first UE and a second UE perform D2D communication, the first UE or the second UE may detect a PHICH channel sent by a base station to a third UE, where the third UE is a UE performing data communication with the base station, and if Negative ACKnowledgement (NACK) is detected, it is determined that D2D communication between the first UE and the second UE causes interference to cellular communication of the base station, so as to reduce D2D transmission power, and otherwise, the D2D transmission power is increased.

However, in the implementation process of the prior art, the first UE or the second UE cannot determine whether the NACK sent by the base station is caused by the own D2D communication, which results in unnecessary reduction of D2D communication power between the first UE and the second UE, and thus reduces the performance of D2D communication.

Disclosure of Invention

In order to solve the above technical problem, the present invention provides a device-to-device communication method and apparatus, so as to solve the problem of low performance of D2D communication.

In order to achieve the object of the present invention, the present invention provides a device-to-device communication method, comprising: a device-to-device communication method, comprising:

a first User Equipment (UE) acquires a first power value, wherein the first power value comprises a maximum standard power value of data sent by the first UE, and the maximum standard power value comprises a first target power value which is smaller than or equal to a power value of the first UE and is received by a base station when the first UE sends data by adopting the maximum standard power value;

the first UE obtaining a second power value, the second power value comprising a power value at which the first UE communicates with a second UE for device-to-device D2D;

and the first UE compares the first power value, the second power value and a third power value, and determines that the minimum power value is the output power of the first UE for sending data to the second UE, wherein the third power value comprises the maximum transmission power value of the first UE.

Further, the obtaining, by the first user equipment UE, a first power value includes:

the first UE acquires a first type of open-loop power control signaling sent by a base station, wherein the first type of open-loop power control signaling comprises any one or a combination of the following: a first target power parameter, a first path loss compensation factor parameter;

the first UE obtains measurement information sent by a base station, and determines a first path loss, where the first path loss includes an uplink path loss between the first UE and the base station, and the measurement information includes at least one or any combination of the following: a common reference signal CRS and a channel state information reference signal CSI-RS;

and the first UE determines a first power value according to the first type of open loop power control signaling and the first path loss.

Further, the determining, by the first UE, a first power value according to the first type of open loop power control signaling and the first path loss includes:

the first UE is according to P_Celluar，c(i)＝10log10(M_D2D，c(i))+P_{O_Celluar，c}+α_Celluar，c·PL_Celluar，cObtaining the first power value P of the first UE on cell c, subframe i_Celluar，c(i) Wherein M is_D2D，c(i) Denotes the number of resource blocks RB, P, used for the transmission of physical channels in cell c, sub-frame i_{O_Celluar，c}Representing a first target received power of said physical channel on cell c, α_Celluar，cA first path loss compensation factor representing said physical channel on cell c, said physical channel comprising: a physical sideline control channel PSCCH or a physical sideline shared channel PSSCH or a physical sideline discovery channel PSDCH.

Further, the obtaining, by the first UE, a second power value includes:

the first UE acquires a second type of open loop power control signaling sent by a base station, wherein the second type of open loop power control signaling comprises any one or a combination of the following: a second target power parameter, a second path loss compensation factor parameter;

the first UE acquires parameter response information sent by the second UE, determines a second path loss, wherein the second path loss comprises the path loss of a D2D communication link between the first UE and the second UE, and the parameter response information comprises at least any one or the combination of a channel Sounding Reference Signal (SRS), a demodulation reference signal (DMRS), a confirmation character (ACK) and a Negative Acknowledgement (NACK);

and the first UE determines a second power value according to the second type of open loop power control signaling and the second path loss.

Further, the determining, by the first UE, a second power value according to the second type of open-loop power control signaling and the second path loss includes:

the first UE is according to the following formula:

P_D2D，c(i)＝10log₁₀(M_D2D，c(i))+P_{O_D2D，c}+α_D2D，c·PL_D2D，c，

obtaining the second power value P_D2D，c(i) Wherein the second target power parameter P_{O_D2D，c}Is the D2D target received power, α, in the D2D link on carrier c_D2D，cIs the second path loss compensation factor. PL_D2D，cIs the second path loss of the D2D communication link between the first UE and the second UE.

Further, after the first UE obtains the second type of open loop power control signaling sent by the base station, the method further includes:

the first UE acquires a second type of closed-loop power control signaling, wherein the second type of closed-loop power control signaling comprises any one or a combination of the following: a first parameter and a second parameter, where the first parameter is a closed-loop power control adjustment configured by the first UE, and the second parameter is a quantity configured by the first UE and related to a device-to-device modulation and coding scheme D2D MCS;

the first UE determines a second power value according to the second type of open-loop power control signaling and the second path loss, including:

and the first UE determines a second power value according to the second type of open-loop power control signaling, the second path loss and the second type of closed-loop power control signaling.

Further, the determining, by the first UE, a second power value according to the second type of open-loop power control signaling, the second path loss, and the second type of closed-loop power control signaling includes:

the first UE is according to the following formula:

P_D2D，c(i)＝10log₁₀(M_D2D，c(i))+P_{O_D2D，c}+α_D2D，c·PL_D2D，c+Δ_{TF_D2D，c}(i)+f_D2D，c(i)

obtaining the second power value P_D2D，c(i) Wherein the second target power parameter P_{O_D2D，c}Is the D2D target received power, α, in the D2D link on carrier c_D2D，cIs the second path loss compensation factor. PL_D2D，cIs a path loss estimate for a unicast D2D link between the first UE and the second UE, the second parameter Δ_{TF_D2D，c}(i) Is a quantity related to the D2D MCS, the first parameter f_D2D，c(i) Is the closed loop power control adjustment.

Further, the comparing, by the first UE, the first power value, the second power value, and a third power value, and determining that the minimum power is an output power for the first UE to send data to the second UE, where the third power value includes a maximum transmission power value of the first UE, includes:

the first UE compares the first power value with the second power value, and determines that the minimum value is first output power;

the first UE determines a second output power according to the first output power and the second closed-loop power control signaling;

and the first UE compares the second output power with the third power value and determines the minimum value as the output power.

Further, the determining, by the first UE, a second output power according to the first output power and the second type of closed-loop power control signaling includes:

the first UE sums the first output power with the first parameter to obtain the second output power; or

The first UE sums the first output power and the second parameter to obtain the second output power; or

And the first UE sums the first output power, the first parameter and the second parameter to obtain the second output power.

The present invention also provides a device-to-device communication apparatus, comprising:

a first obtaining module, configured to obtain a first power value, where the first power value includes a maximum standard power value of data sent by the first UE, and the maximum standard power value includes a first target power value configured by a base station RRC signaling when the first UE sends data by using the maximum standard power value, where the power value received by the base station is smaller than or equal to the power value of the first UE;

a second obtaining module, configured to obtain a second power value, where the second power value includes a power value for the first UE to perform device-to-device D2D communication with a second UE;

a determining module, configured to compare the first power value, the second power value, and a third power value, and determine that a minimum power is an output power of the first UE for sending data to the second UE, where the third power value includes a maximum transmission power value of the first UE.

Further, the first obtaining module is specifically configured to obtain, by the first UE, a first type of open-loop power control signaling sent by a base station, where the first type of open-loop power control signaling includes any one of or a combination of the following: a first target power parameter, a first path loss compensation factor parameter; obtaining measurement information sent by a base station, and determining a first path loss, where the first path loss includes an uplink path loss between the first UE and the base station, and the measurement information includes at least one or any combination of the following: a common reference signal CRS and a channel state information reference signal CSI-RS; and determining a first power value according to the first open loop power control signaling and the first path loss.

Further, the first obtaining module is specifically configured to obtain the value according to P_Celluar，c(i)＝10log10(M_D2D，c(i))+P_{O_Celluar，c}+α_Celluar，c·PL_Celluar，cObtaining the first power value P of the first UE on cell c, subframe i_Celluar，c(i) Wherein M is_D2D，c(i) Denotes the number of resource blocks RB, P, used for the transmission of physical channels in cell c, sub-frame i_{O_Celluar，c}Representing a first target received power of said physical channel on cell c, α_Celluar，cA first path loss compensation factor representing said physical channel on cell c, said physical channel comprising: a physical sideline control channel PSCCH or a physical sideline shared channel PSSCH or a physical sideline discovery channel PSDCH.

Further, the second obtaining module is specifically configured to obtain a second type of open-loop power control signaling sent by the base station, where the second type of open-loop power control signaling includes any one of or a combination of the following: a second target power parameter, a second path loss compensation factor parameter; acquiring parameter response information sent by the second UE, and determining second path loss, wherein the second path loss comprises the path loss of a D2D communication link between the first UE and the second UE, and the parameter response information comprises at least any one or combination of a channel Sounding Reference Signal (SRS), a demodulation reference signal (DMRS), an Acknowledgement Character (ACK) and a Negative Acknowledgement (NACK); and determining a second power value according to the second type of open loop power control signaling and the second path loss.

Further, the second obtaining module is specifically configured to:

P_D2D，c(i)＝10log₁₀(M_D2D，c(i))+P_{O_D2D，c}+α_D2D，c·PL_D2D，c，

obtaining the second power value P_D2D，c(i) Wherein the second target power parameter P_{O_D2D，c}Is the D2D target received power, α, in the D2D link on carrier c_D2D，cIs the second path loss compensation factor. PL_D2D，cIs the second path loss of the D2D communication link between the first UE and the second UE.

Further, the second obtaining module is further configured to obtain a second type of closed-loop power control signaling, where the second type of closed-loop power control signaling includes any one of or a combination of the following: a first parameter and a second parameter, where the first parameter is a closed-loop power control adjustment configured by the first UE, and the second parameter is a quantity configured by the first UE and related to a device-to-device modulation and coding scheme D2D MCS; and determining a second power value according to the second type of open-loop power control signaling, the second path loss and the second type of closed-loop power control signaling.

Further, the second obtaining module is specifically configured to:

P_D2D，c(i)＝10log₁₀(M_D2D，c(i))+P_{O_D2D，c}+α_D2D，c·PL_D2D，c，+Δ_{TF_D2D，c}(i)+f_D2D，c(i)；

wherein, P_D2D，c(i) For the second power value, a second target power parameter P_{O_D2D，c}Is the D2D target received power, α, in the D2D link on carrier c_D2D，cIs a second path loss compensation factor, PL_D2D，cIs a path loss estimate for a unicast D2D link between the first UE and the second UE, the second parameter Δ_{TF_D2D，c}(i) Is a quantity related to a device-to-device modulation and coding scheme D2D MCS, and the first parameter f_D2D，c(i) Is the closed loop power control adjustment.

17. The apparatus according to claim 14, wherein the determining module is specifically configured to compare the first power value and the second power value, and determine that the minimum value is the first output power; determining a second output power according to the first output power and the second closed-loop power control signaling; and comparing the second output power with the third power value, and determining the minimum value as the output power.

Further, the determining module is specifically configured to sum the first output power and the first parameter to obtain the second output power; or, summing the first output power and the second parameter to obtain the second output power; or summing the first output power, the first parameter and the second parameter to obtain the second output power.

Compared with the prior art, the method comprises the steps that first User Equipment (UE) acquires a first power value, wherein the first power value comprises a maximum standard power value of data sent by the first UE, and the maximum standard power value comprises a first target power value which is smaller than or equal to a power value of the first UE and is configured by base station RRC signaling when the first UE sends data by adopting the maximum standard power value; the first UE obtaining a second power value, the second power value comprising a power value at which the first UE communicates with a second UE for device-to-device D2D; and the first UE compares the first power value, the second power value and a third power value, and determines that the minimum power is the output power of the first UE for sending data to the second UE, wherein the third power value comprises the maximum transmission power value of the first UE. The determination of the output power of the data sent by the first UE to the second UE is realized, and further, under the condition that the D2D communication performance is not affected, the interference power of the first UE to the base station is ensured not to exceed the first target power value configured by the RRC signaling of the base station.

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

Drawings

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

FIG. 1 is a flow chart illustrating an embodiment of a method for communicating by a device of the present invention;

FIG. 2 is a flowchart illustrating a second embodiment of a communication method of the device of the present invention;

FIG. 3 is a flowchart illustrating a communication method according to a third embodiment of the present invention;

FIG. 4 is a flowchart illustrating a communication method according to a fourth embodiment of the present invention;

FIG. 5 is a flow chart of a fifth embodiment of a method for communicating by a device of the present invention;

FIG. 6 is a flowchart illustrating a communication method according to a sixth embodiment of the present invention;

FIG. 7 is a flowchart illustrating a seventh exemplary embodiment of a communication method of the present invention;

fig. 8 is a schematic structural diagram of an embodiment of a device communication apparatus according to the present invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, embodiments of the present invention will be described in detail below with reference to the accompanying drawings. It should be noted that the embodiments and features of the embodiments in the present application may be arbitrarily combined with each other without conflict.

The device-to-device communication method provided by the embodiment of the invention can be particularly applied to the D2D communication between the first UE and the second UE, wherein the first UE or the second UE can be any terminal device such as a mobile phone terminal or an intelligent computer. The device-to-device communication method provided in this embodiment may be specifically executed by a device-to-device communication apparatus, and the device-to-device communication apparatus may be integrated in a terminal device or separately provided, where the device-to-device communication apparatus may be implemented in a software and/or hardware manner. The device-to-device communication method and apparatus provided in the present embodiment are described in detail below.

Fig. 1 is a schematic flowchart of an embodiment of a device communication method according to the present invention, and as shown in fig. 1, the device communication method provided by the present invention includes:

step 101, a first user equipment UE obtains a first power value.

The applicable scenarios of this embodiment are: the first UE and the second UE perform D2D communication, that is, a link between the first UE and the second UE is a signal link, and the base station may also receive data sent by the first UE, that is, the link between the base station and the first UE is an interference link. The present embodiment determines the transmit power of D2D based on the link quality of the signal link and the interfering link.

In this embodiment, the first power value includes a maximum standard power value for the first UE to transmit data, where the maximum standard power value includes a power value of the first UE received by the base station when the first UE transmits data by using the maximum standard power value, which is less than or equal to a first target power value configured by RRC signaling of the base station. For example, in a scenario where a first UE communicates with a second UE2, a signal transmitted by the first UE reaches a base station after being attenuated by path loss, and if the strength of a signal received by the base station is greater than a first target power configured by a base station RRC signaling, it is considered that the UE1 causes strong interference to the base station, that is, the power value of data transmitted by the first UE is greater than the maximum standard power value.

The obtaining of the first power value for the first user equipment UE includes at least the following implementations:

in a first implementation manner, the first UE directly obtains a first power value sent by a base station.

In a second implementation manner, the first UE obtains a first type of open-loop power control signaling sent by a base station, where the first type of open-loop power control signaling includes any one or a combination of the following: a first target power parameter, a first path loss compensation factor parameter; the first UE obtains measurement information sent by a base station, and determines a first path loss, where the first path loss includes an uplink path loss between the first UE and the base station, and the measurement information includes at least one or any combination of the following: a common reference signal CRS and a channel state information reference signal CSI-RS; and the first UE determines a first power value according to the first type of open-loop power value control signaling and the first path loss.

For example, the determining, by the first UE, a first power value according to the first type of open loop power control signaling and the first path loss includes:

the first UE is according to P_Celluar，c(i)＝10log10(M_D2D，c(i))+P_{O_Celluar，c}+α_Celluar，c·PL_Celluar，cObtaining the first power value P of the first UE on cell c, subframe i_Celluar，c(i) Wherein M is_D2D，c(i) Denotes the number of resource blocks RB, P, used for the transmission of physical channels in cell c, sub-frame i_{O_Celluar，c}Representing the target received power of the physical channel on cell c, α_Celluar，cA first path loss compensation factor representing said physical channel on cell c, said physical channel comprising: a Physical edge Control Channel (PSCCH), a Physical edge Shared Channel (PSCCH), or a Physical edge Discovery Channel (PSDCH).

And 102, the first UE acquires a second power value.

The second power value in this embodiment includes: a power value at which the first UE communicates device-to-device D2D with a second UE.

Obtaining the second power value for the first UE includes at least the following implementations:

in a first implementation manner, the first UE directly obtains the second power value sent by the base station or the second UE.

In a second implementation manner, the first UE obtains a second type of open-loop power control signaling sent by a base station, where the second type of open-loop power control signaling includes any one or a combination of the following: a second target power parameter, a second path loss compensation factor parameter; the first UE acquires parameter response information sent by the second UE, determines a second path loss, wherein the second path loss comprises the path loss of a D2D communication link between the first UE and the second UE, and the parameter response information comprises at least any one or the combination of a channel Sounding Reference Signal (SRS), a demodulation reference signal (DMRS), a confirmation character (ACK) and a Negative Acknowledgement (NACK); and the first UE determines a second power value according to the second type of open loop power control signaling and the second path loss.

For example, the determining, by the first UE, a second power value according to the second type of open loop power control signaling and the second path loss includes:

the first UE is according to the following formula:

P_D2D，c(i)＝10log₁₀(M_D2D，c(i))+P_{O_D2D，c}+α_D2D，c·PL_D2D，c，

obtaining the second power value P_D2D，c(i) Wherein the second target power parameter P_{O_D2D，c}Is the D2D target received power, α, in the D2D link on carrier c_D2D，cIs the second path loss compensation factor. PL_D2D，cIs the second path loss of the D2D communication link between the first UE and the second UE.

In a third implementation manner, on the basis of the second implementation manner, after the first UE acquires the second type of open-loop power control signaling sent by the base station, the method further includes:

the first UE acquires a second type of closed-loop power control signaling, wherein the second type of closed-loop power control signaling comprises any one or a combination of the following: a first parameter, a second parameter, the first parameter being a closed loop power control adjustment configured by the first UE, the second parameter being a D2D MCS related quantity configured by the first UE;

the first UE determines a second power value according to the second type of open-loop power control signaling and the second path loss, including:

and the first UE determines a second power value according to the second type of open-loop power control signaling, the second path loss and the second type of closed-loop power control signaling.

Specifically, the determining, by the first UE, a second power value according to the second type of open-loop power control signaling, the second path loss, and the second type of closed-loop power control signaling includes:

the first UE is according to the following formula:

P_D2D，c(i)＝10log₁₀(M_D2D，c(i))+P_{O_D2D，c}+α_D2D，c·PL_D2D，c+Δ_{TF_D2D，c}(i)+f_D2D，c(i)

obtaining the second power value P_D2D，c(i) Wherein the second target power parameter P_{O_D2D，c}Is the D2D target received power, α, in the D2D link on carrier c_D2D，cIs the second path loss compensation factor. PL_D2D，cIs a path loss estimate for a unicast D2D link between the first UE and the second UE, the second parameter Δ_{TF_D2D，c}(i) Is a quantity related to the D2D MCS, the first parameter f_D2D，c(i) Is the closed loop power control adjustment.

Step 103, the first UE compares the first power value, the second power value and the third power value, and determines that the minimum power is the output power of the data sent by the first UE to the second UE.

In this embodiment, the third power value includes a maximum transmit power value for the first UE.

Comparing the first power value, the second power value and the third power value for the first UE, and determining that the minimum power is the output power of the first UE for transmitting data to the second UE at least includes the following implementation manners:

in a first implementation manner, the first UE compares the first power value, the second power value, and the third power value, and determines that the minimum power is an output power of the first UE for transmitting data to the base station.

In a second implementation manner, the first UE compares the first power value with the second power value, and determines that the minimum value is a first output power; the first UE determines a second output power according to the first output power and the second closed-loop power control signaling; and the first UE compares the second output power with the third power value and determines the minimum value as the output power.

For example, the determining, by the first UE, the second output power according to the first output power and the second type of closed loop power control signaling may include:

the first UE sums the first output power with the first parameter to obtain the second output power; or

The first UE sums the first output power and the second parameter to obtain the second output power; or

And the first UE sums the first output power, the first parameter and the second parameter to obtain the second output power.

In this embodiment, a first user equipment UE obtains a first power value, where the first power value includes a maximum standard power value of data sent by the first UE, and the maximum standard power value includes a first target power value configured by a base station RRC signaling that is received by a base station when the first UE sends data by using the maximum standard power value; the first UE obtaining a second power value, the second power value comprising a power value at which the first UE communicates with a second UE for device-to-device D2D; and the first UE compares the first power value, the second power value and a third power value, and determines that the minimum power is the output power of the first UE for sending data to the second UE, wherein the third power value comprises the maximum transmission power value of the first UE. The determination of the output power of the data sent by the first UE to the second UE is realized, and further, under the condition that the D2D communication performance is not affected, the interference power of the first UE to the base station is ensured not to exceed the first target power value configured by the RRC signaling of the base station.

Fig. 2 is a schematic flowchart of a second embodiment of the device communication method of the present invention, and as shown in fig. 2, the device communication method provided by the present invention includes:

step 201, a first UE, that is, UE1, obtains a first type of open loop power control signaling sent by a base station, where the first type of open loop power control signaling includes a first target power parameter.

Step 202, the first UE obtains measurement information sent by the base station, and determines a first path loss.

The first path loss includes an uplink path loss between the first UE and the base station, and the measurement information includes at least one or any combination of the following: a common reference signal CRS and a channel state information reference signal CSI-RS;

step 203, the first UE determines a first power value according to the first type of open-loop power value control signaling and the first path loss.

In particular, the UE1 has a first power value P on carrier c, i.e. cell c, subframe i_Celluar，c(i)：P_Celluar，c(i)＝10log₁₀(M_D2D，c(i))+P_{O_Celluar，c}+PL_Celluar，cWherein M is_D2D，c(i) Denotes the number of resource blocks RB, P, used for the transmission of physical channels in cell c, sub-frame i_{O_Celluar，c}A first target received power representing the physical channel on cell c, the physical channel comprising: physical downlink control channelPSCCH or pscsch or packet switched data channel PSDCH.

Step 204, the first UE acquires a second type open loop power control signaling sent by the base station, wherein the second type open loop power control signaling comprises a second target power parameter;

step 205, the first UE obtains the parameter response information sent by the second UE, and determines the second path loss.

Specifically, the second path loss includes the path loss of a D2D communication link between the first UE and the second UE, and the parameter response information includes at least any one or a combination of a channel sounding reference signal SRS, a demodulation reference signal DMRS, an acknowledgement character ACK, and a negative acknowledgement NACK;

and step 206, the first UE determines a second power value according to the second type of open-loop power control signaling and the second path loss.

Specifically, the first UE is according to the following formula:

P_D2D，c(i)＝10log₁₀(M_D2D，c(i))+P_{O_D2D，c}+PL_D2D，c

obtaining the second power value P_D2D，c(i) Wherein the second target power parameter P_{O_D2D，c}Is the D2D target received power in the D2D link on carrier c. PL_D2D，cIs the second path loss of the D2D communication link between the first UE and the second UE.

Step 207, the first UE compares the first power value, the second power value and the third power value, and determines that the minimum power is the output power of the first UE for transmitting data to the base station.

In this embodiment, the third power value P_CMAX，c(i) Is the maximum transmit power of the UE1 on carrier c.

Specifically, the actual transmission power of the UE1 on the carrier c and the subframe i is determined, that is, the output power is:

P_{D2D_Final，c}(i)＝min(P_CMAX，c(i)，P_Celluar，c(i)，P_D2D，c(i))

step 208, UE1 according to output power P_{D2D_Final，c}(i) And transmits control signaling or data or discovery signals for the D2D link.

Fig. 3 is a schematic flowchart of a third embodiment of the device communication method of the present invention, and as shown in fig. 3, the device communication method provided by the present invention includes:

step 301, a first UE, that is, UE1, obtains a first type of open-loop power control signaling sent by a base station, where the first type of open-loop power control signaling includes a first target power parameter and a first path loss compensation factor parameter.

Step 302, the first UE obtains measurement information sent by the base station, and determines a first path loss.

The first path loss includes an uplink path loss between the first UE and the base station, and the measurement information includes at least one or any combination of the following: a common reference signal CRS and a channel state information reference signal CSI-RS;

step 303, the first UE determines a first power value according to the first type of open-loop power value control signaling and the first path loss.

In particular, the UE1 has a first power value P on carrier c, i.e. cell c, subframe i_Celluar，c(i)：

P_Celluar，c(i)＝10log₁₀(M_D2D，c(i))+P_{O_Celluar，c}+α_Celluar，c·PL_Celluar，cWherein M is_D2D，c(i) Denotes the number of resource blocks RB, P, used for the transmission of physical channels in cell c, sub-frame i_{O_Celluar，c}Representing a first target received power of said physical channel on cell c, α_Celluar，cA first path loss compensation factor representing said physical channel on cell c, said physical channel comprising: physical downlinkControl channel PSCCH or PSSCH or packet switched data channel PSDCH, &lTtT translation = α "&gTt α &lTt/T &gTt_Celluar，cIs a path loss compensation factor parameter.

Step 304, the first UE obtains a second type of open-loop power control signaling sent by the base station, where the second type of open-loop power control signaling includes a second target power parameter and a second path loss compensation factor.

And 305, the first UE acquires the parameter response information sent by the second UE, and determines the second path loss.

Specifically, the second path loss includes the path loss of a D2D communication link between the first UE and the second UE, and the parameter response information includes at least any one or a combination of a channel sounding reference signal SRS, a demodulation reference signal DMRS, an acknowledgement character ACK, and a negative acknowledgement NACK;

step 306, the first UE determines a second power value according to the second type of open-loop power control signaling and the second path loss.

Specifically, the first UE is according to the following formula:

P_D2D，c(i)＝10log₁₀(M_D2D，c(i))+P_{O_D2D，c}+α_D2D，c·PL_D2D，c，

obtaining the second power value P_D2D，c(i) Wherein the second target power parameter P_{O_D2D，c}Is the D2D target received power, α, in the D2D link on carrier c_D2D，cIs the second path loss compensation factor. PL_D2D，cIs the second path loss of the D2D communication link between the first UE and the second UE.

Step 307, the first UE compares the first power value, the second power value and the third power value, and determines that the minimum power is the output power of the data sent to the base station by the first UE.

In this embodiment, the third power value P_CMAX，c(i) Is the maximum transmit power of the UE1 on carrier c.

Specifically, the actual transmission power of the UE1 on the carrier c and the subframe i is determined, that is, the output power is:

P_{D2D_Final，c}(i)＝min(P_CMAX，c(i)，P_Celluar，c(i)，P_D2D，c(i))

step 308, UE1 according to output power P_{D2D_Final，c}(i) And transmits control signaling or data or discovery signals for the D2D link.

It should be noted that, the steps 304-306 and the steps 301-303 are not in sequence.

Fig. 4 is a schematic flowchart of a fourth embodiment of the device communication method of the present invention, and as shown in fig. 4, the device communication method provided by the present invention includes:

step 401, a first UE, that is, UE1, obtains a first type of open loop power control signaling sent by a base station, where the first type of open loop power control signaling includes a first target power parameter and a first path loss compensation factor parameter.

Step 402, the first UE obtains measurement information sent by the base station, and determines a first path loss.

The first path loss includes an uplink path loss between the first UE and the base station, and the measurement information includes at least one or any combination of the following: a common reference signal CRS and a channel state information reference signal CSI-RS;

step 403, the first UE determines a first power value according to the first type of open-loop power value control signaling and the first path loss.

In particular, the UE1 has a first power value P on carrier c, i.e. cell c, subframe i_Celluar，c(i)：

P_Celluar，c(i)＝10log₁₀(M_D2D，c(i))+P_{O_Celluar，c}+α_Celluar，c·PL_Celluar，cWherein M is_D2D，c(i) Indicating a cellNumber of resource blocks RB, P, used for transmission of physical channel in zone c, subframe i_{O_Celluar，c}Representing a first target received power of said physical channel on cell c, α_Celluar，cRepresents a first path loss compensation factor of the physical channel on the cell c, the physical channel comprising a physical downlink control channel PSCCH or PSSCH or a packet switched data channel PSDCH, & lTtT translation = &/T &_Celluar，cIs a path loss compensation factor parameter.

Step 404, the first UE obtains a second type of open-loop power control signaling sent by the base station, where the second type of open-loop power control signaling includes a second target power parameter.

Step 405, the first UE acquires the second type of closed loop power control signaling.

In this embodiment, the second type of closed loop power control signaling includes any one or a combination of the following: the first parameter is a closed-loop power control adjustment amount configured by the first UE, and the second parameter is an amount configured by the first UE and related to a Device to Device Modulation and Coding Scheme (D2D MCS). For example, the MCS determines the adopted modulation scheme (e.g., QPSK, 16QAM, 64QAM) and code rate (high code rate, low redundant bit rate).

And step 406, the first UE acquires the parameter response information sent by the second UE, and determines the second path loss.

Specifically, the second path loss includes the path loss of a D2D communication link between the first UE and the second UE, and the parameter response information includes at least any one or a combination of a channel sounding reference signal SRS, a demodulation reference signal DMRS, an acknowledgement character ACK, and a negative acknowledgement NACK;

step 407, the first UE determines a second power value according to the second type of open-loop power control signaling, the second path loss, and the second type of closed-loop power control signaling.

Specifically, the UE1 measures UE2, estimating path loss PL of the UE1 and the UE2_D2D，c. According to PL_D2D，cTransmission bandwidth M of UE1_D2D，c(i) The MCS level used by the UE1, the second type of open-loop power control signaling, and the second type of closed-loop power control signaling calculate a second power value that the UE1 can satisfy the D2D unicast communication signal strength requirement on the carrier c and the subframe i:

P_D2D，c(i)＝10log₁₀(M_D2D，c(i))+P_{O_D2D，c}+α_D2D，c·PL_D2D，c+Δ_{TF_D2D，c}(i)+f_D2D，c(i)

step 408, the first UE compares the first power value, the second power value and the third power value, and determines that the minimum power is the output power of the data sent by the first UE to the base station.

In this embodiment, the third power value P_CMAX，c(i) Is the maximum transmit power of the UE1 on carrier c.

Specifically, the actual transmission power of the UE1 on the carrier c and the subframe i is determined, that is, the output power is:

P_{D2D_Final，c}(i)＝min(P_CMAX，c(i)，P_Celluar，c(i)，P_D2D，c(i))

step 409, UE1 according to output power P_{D2D_Final，c}(i) And transmits control signaling or data or discovery signals for the D2D link.

It should be noted that, the steps 404 and 407 and the steps 401 and 403 are not in sequence.

Fig. 5 is a schematic flowchart of a fifth embodiment of the device communication method of the present invention, and as shown in fig. 5, the device communication method provided by the present invention includes:

step 501, the first UE, that is, UE1, obtains a first type of open-loop power control signaling and a second type of open-loop power control signaling sent by the base station, where the first type of open-loop power control signaling includes a target powerRate parameter P_{O_Celluar，c}And path loss compensation factor parameter α_Celluar，c. The second kind of open loop power control signaling includes a target power parameter P_{O_D2D，c}And path loss compensation factor α_D2D，c。

Step 502, the base station or the second UE configures a second type of closed-loop power control signaling to the first UE, i.e., the sending-end UE 1;

step 503, UE1 estimates uplink path loss PL of the UE and the serving base station by measuring CRS and/or CSI-RS pilot transmitted by the serving base station_Celluar，c。

In particular, according to PL_Celluar，cTransmission bandwidth M of UE1_D2D，c(i) Calculating the power upper limit value of the UE1 on the carrier c and the subframe i, which does not cause strong interference to the base station, namely a first power value:

P_Celluar，c(i)＝10log₁₀(M_D2D，c(i))+P_{O_Celluar，c}+α_Celluar，c·PL_Celluar，c

step 504, UE1 according to path loss PL of UE1 and UE2_D2D，cTransmission bandwidth M of UE1_D2D，c(i) The second type of open-loop power control signaling and the second type of closed-loop power control signaling calculate the power of the UE1 that can meet the requirement of the D2D unicast communication signal strength on the carrier c and the subframe i, that is, a second power value:

P_D2D，c(i)＝10log₁₀(M_D2D，c(i))+P_{O_D2D，c}+α_D2D，c·PL_D2D，c+f_D2D，c(i)

specifically, the path loss PL of the UE1 and the UE2 is estimated by measuring the SRS and/or the DMRS and/or the ACK/NACK transmitted by the UE2_D2D，c。

Step 505, UE1 calculates the actual transmission power of UE1 on carrier c and subframe i, i.e. the output power value:

P_{D2D_Final，c}(i)＝min(P_CMAX，c(i)，P_Celluar，c(i)，P_D2D，c(i))

wherein, P_CMAX，c(i) Is the maximum transmit power of the UE1 on carrier c.

Step 506, UE1 according to the output power value P_{D2D_Final，c}(i) And transmits control signaling or data or discovery signals for the D2D link.

In this embodiment, the sequence of steps 502 to 504 may be arbitrarily replaced.

Fig. 6 is a schematic flowchart of a sixth embodiment of the device communication method of the present invention, and as shown in fig. 6, the device communication method provided by the present invention includes:

step 601, the base station configures the first type open loop power control parameter and the second type open loop power control parameter through the RRC signaling, and sends the RRC signaling through an air interface.

The first open loop power control signaling includes a target power parameter P_{O_Celluar，c}And path loss compensation factor parameter α_Celluar，c. The second kind of open loop power control signaling includes a target power parameter P_{O_D2D，c}And path loss compensation factor α_D2D，c。

Step 602, the base station or the second UE configures a second type of closed-loop power control signaling for the first UE, that is, the sending-end UE 1;

step 603, UE1 estimates uplink path loss PL of the UE and the serving base station by measuring CRS and/or CSI-RS pilot transmitted by the serving base station_Celluar，c。

According to PL_Celluar，cTransmission bandwidth M of UE1_D2D，c(i) Calculating the power upper limit value of the UE1 on the carrier c and the subframe i, which does not cause strong interference to the base station, namely a first power value:

P_Celluar，c(i)＝10log₁₀(M_D2D，c(i))+P_{O_Celluar，c}+α_Celluar，c·PL_Celluar，c

step 604, UE1 according to path loss PL of UE1 and UE2_D2D，cNumber of resource blocks M corresponding to transmission bandwidth of UE1_D2D，c(i) The MCS level transmitted by the UE1D2D, the second type of open loop power control signaling, and the power that the UE1 can satisfy the D2D unicast communication signal strength requirement on the carrier c and the subframe i, that is, the second power value:

P_D2D，c(i)＝10log₁₀(M_D2D，c(i))+P_{O_D2D，c}+α_D2D，c·PL_D2D，c+Δ_{TF_D2D，c}(i)

specifically, the path loss PL of the UE1 and the UE2 is estimated by measuring the SRS and/or the DMRS and/or the ACK/NACK transmitted by the UE2_D2D，c。

Step 605, UE1 calculates the actual transmission power of UE1 on carrier c and subframe i, i.e. the output power value:

P_{D2D_Final，c}(i)＝min(P_CMAX，c(i)，P_Celluar，c(i)，P_D2D，c(i))

wherein, P_CMAX，c(i) Is the maximum transmit power of the UE1 on carrier c.

Step 606, UE1 according to the transmission power value P calculated in step 5_{D2D_Final，c}(i) And transmits control signaling or data or discovery signals for the D2D link.

In this embodiment, the sequence of steps 602 to 604 may be arbitrarily replaced.

Fig. 7 is a schematic flowchart of a seventh embodiment of the device communication method of the present invention, and as shown in fig. 7, the device communication method provided by the present invention includes:

step 701, the base station configures a first type of open-loop power control parameter and a second type of open-loop power control parameter through an RRC signaling, and sends the RRC signaling through an air interface.

In particular, open loop power control signaling of the first typeIn, including a target power parameter P_{O_Celluar，c}And path loss compensation factor parameter α_Celluar，c. The second kind of open loop power control signaling includes a target power parameter P_{O_D2D，c}And path loss compensation factor α_D2D，c。

Step 702, the base station or the second UE, i.e. the receiving UE2, configures a second type of closed-loop power control signaling to the first UE, i.e. the transmitting UE 1;

step 703, the UE1 estimates the uplink loss PL of the UE and the serving base station by measuring the CRS and/or CSI-RS pilot transmitted by the serving base station_Celluar，c。

In particular, according to PL_Celluar，cTransmission bandwidth M of UE1_D2D，c(i) Calculating the power upper limit value of the UE1 on the carrier c and the subframe i, which does not cause strong interference to the base station, namely a first power value:

P_Celluar，c(i)＝10log₁₀(M_D2D，c(i))+P_{O_Celluar，c}+α_Celluar，c·PL_Celluar，c

step 704, the UE1 estimates the path loss PL of the UE1 and the UE2 by measuring the SRS and/or DMRS and/or ACK/NACK transmitted by the UE2_D2D，c。

In particular, according to PL_D2D，cTransmission bandwidth M of UE1_D2D，c(i) And the second type of open loop power control signaling calculates the power of the UE1 that can meet the requirement of D2D unicast communication signal strength on carrier c and subframe i, i.e. a second power value:

P_D2D，c(i)＝10log₁₀(M_D2D，c(i))+P_{O_D2D，c}+α_D2D，c·PL_D2D，c

step 705, the UE1 calculates the actual transmission power of the UE1 on the carrier c and the subframe i, i.e. the output power value:

P_{D2D_Final，}(i)＝min{P_CMAX，c(i)，min[P_Celluar，c(i)，P_D2D，c(i)]+Δ_{TF_D2D，c}(i)+f_D2D，c(i)}

wherein f is_D2D，c(i) Is a closed loop correction function (which may be an additive correction or an absolute correction) whose value is related to the TPC command, Δ_{TF_D2D，c}(i) Determined by the MCS of the UE1, P_CMAX，c(i) Is the maximum transmit power of the UE1 on carrier c.

Step 706, UE1 outputs power value P_{D2D_Final，c}(i) And transmits control signaling or data or discovery signals for the D2D link.

In this embodiment, the sequence of steps 702 to 704 may be arbitrarily replaced.

Fig. 7 shows a basic flow of an eighth embodiment of the device communication method provided by the present invention, which is different from that 701-706 corresponds to 801-806 in this embodiment, and the step 706 is different from the calculation method for obtaining the output power value in the step 806. The equipment communication method provided by the invention comprises the following steps:

step 801: and the base station configures the first type of open-loop power control parameters and the second type of open-loop power control parameters through the RRC signaling, and sends the RRC signaling through an air interface.

Specifically, the first type of open loop power control signaling includes a target power parameter P_{O_Celluar，c}And path loss compensation factor parameter α_Celluar，c. The second kind of open loop power control signaling includes a target power parameter P_{O_D2D，c}And path loss compensation factor α_D2D，c

Step 802: the base station or the second UE, i.e. the receiving end UE2, configures the second type of closed-loop power control signaling to the transmitting end UE 1;

step 803: UE1 estimates the uplink path loss PL between the UE and the serving base station by measuring the CRS and/or CSI-RS pilot transmitted by the serving base station_Celluar，c。

In particular, according to PL_Celluar，cTransmission bandwidth M of UE1_D2D，c(i) Calculating the power upper limit value of the UE1 on the carrier c and the subframe i, which does not cause strong interference to the base station, namely a first power value:

P_Celluar，c(i)＝10log₁₀(M_D2D，c(i))+P_{O_Celluar，c}+α_Celluar，c·PL_Celluar，c

step 804, the UE1 estimates the path loss PL of the UE1 and the UE2 by measuring the SRS and/or the DMRS and/or the ACK/NACK transmitted by the UE2_D2D，c。

In particular, according to PL_D2D，cTransmission bandwidth M of UE1_D2D，c(i) And the second type of open loop power control signaling calculates the power of the UE1 that can meet the requirement of D2D unicast communication signal strength on carrier c and subframe i, i.e. the second power:

P_D2D，c(i)＝10log₁₀(M_D2D，c(i))+P_{O_D2D，c}+α_D2D，c·PL_D2D，C

step 805, the UE1 calculates the actual transmission power of the UE1 on the carrier c and the subframe i, i.e. the output power value:

P_{D2D_final，c}(i)＝min{P_CMAX，c(i)，min[P_Celluar，c(i)，P_D2D，c(i)]+Δ_{TF_D2D，c}(i)}

wherein, Delta_{TF_D2D，c}(i) Determined by the MCS of the UE1, P_CMAX，c(i) Is the maximum transmit power of the UE1 on carrier c.

Step 806, UE1 outputs power value P_{D2D_Final，c}(i) And transmits control signaling or data or discovery signals for the D2D link.

In this embodiment, the sequence of steps 802 to 804 may be arbitrarily replaced.

In the ninth embodiment of the device communication method provided by the present invention, the basic flow is as shown in fig. 7, and the difference is that 701-706 corresponds to 901-906 of the present embodiment, and the step 706 is different from the calculation method for acquiring the output power value in the step 906. The equipment communication method provided by the invention comprises the following steps:

step 901, the base station configures a first type open loop power control parameter and a second type open loop power control parameter through an RRC signaling, and sends the RRC signaling through an air interface.

Specifically, the first type of open loop power control signaling includes a target power parameter P_{O_Celluar，c}And path loss compensation factor parameter α_Celluar，c. The second kind of open loop power control signaling includes a target power parameter P_{O_D2D，c}And path loss compensation factor α_D2D，c。

Step 902, the base station or the second UE, i.e. the receiving UE2, configures a second type of closed-loop power control signaling to the first UE, i.e. the transmitting UE 1;

step 903, the UE1 estimates the uplink loss PL of the UE and the serving base station by measuring CRS and/or CSI-RS pilot transmitted by the serving base station_Celluar，c。

In particular, according to PL_Celluar，cTransmission bandwidth M of UE1_D2D，c(i) Calculating the power upper limit value of the UE1 on the carrier c and the subframe i, which does not cause strong interference to the base station, according to the first open-loop power control signaling:

P_Celluar，c(i)＝10log₁₀(M_D2D，c(i))+P_{O_Celluar，c}+α_Celluar，c·PL_Celluar，c

step 904, the UE1 estimates the path loss PL of the UE1 and the UE2 by measuring the SRS and/or DMRS and/or ACK/NACK transmitted by the UE2_D2D，c。

In particular, according to PL_D2D，cTransmission bandwidth M of UE1_D2D，c(i) And the second type of open loop power control signaling calculates the power of the UE1 which can meet the requirement of the D2D unicast communication signal strength on the carrier c and the subframe i:

P_D2D，c(i)＝10log₁₀(M_D2D，c(i))+P_{O_D2D，c}+α_D2D，c·PL_D2D，c

step 905, the UE1 calculates the actual transmission power of the UE1 on the carrier c and the subframe i, that is, the output power value:

P_{D2D_Final，c}(i)＝min{P_CMAX，c(i)，min[P_Celluar，c(i)，P_D2D，c(i)]+f_D2D，c(i)}

wherein f is_D2D，c(i) Is a closed loop correction function (which may be an accumulated correction or an absolute correction) whose value is related to the TPC command, P_CMAX，c(i) Is the maximum transmit power of the UE1 on carrier c.

Step 906, UE1 according to the output power value P_{D2D_Final，c}(i) And transmits control signaling or data or discovery signals for the D2D link.

In this embodiment, the order of steps 902 to 904 may be arbitrarily replaced.

Fig. 8 is a schematic structural diagram of an embodiment of the device communication apparatus of the present invention, and as shown in fig. 8, the device-to-device communication apparatus includes: a first obtaining module 101, a second obtaining module 102 and a determining module 103. Wherein,

a first obtaining module 101, configured to obtain a first power value, where the maximum standard power value of data sent by the first UE includes a power value of the first UE received by a base station that is less than or equal to a first target power value configured for a base station RRC signaling when the first UE sends data by using the maximum standard power value;

a second obtaining module 102, configured to obtain a second power value, where the second power value includes a power value for the first UE to perform device-to-device D2D communication with a second UE;

a determining module 103, configured to compare the first power value, the second power value, and a third power value, and determine that the minimum power is an output power for the first UE to send data to the second UE, where the third power value includes a maximum transmit power value of the first UE.

In this embodiment, a first user equipment UE acquires a first power value, where the first power value includes a maximum standard power value of data sent by the first UE, and the maximum standard power value includes a first target power value configured by a base station RRC signaling, where a power value of the first UE received by a base station is smaller than or equal to the maximum standard power value when the first UE sends data by using the maximum standard power value; the first UE obtaining a second power value, the second power value comprising a power value at which the first UE communicates with a second UE for device-to-device D2D; and the first UE compares the first power value, the second power value and a third power value, and determines that the minimum power is the output power of the first UE for sending data to the second UE, wherein the third power value comprises the maximum transmission power value of the first UE. The determination of the output power of the data sent by the first UE to the second UE is realized, and further, under the condition that the D2D communication performance is not affected, the interference power of the first UE to the base station is ensured not to exceed the first target power value configured by the RRC signaling of the base station.

Further, on the basis of the foregoing embodiment, the first obtaining module 101 is specifically configured to obtain, by the first UE, a first type of open-loop power control signaling sent by a base station, where the first type of open-loop power control signaling includes any one of or a combination of the following: a first target power parameter, a first path loss compensation factor parameter; obtaining measurement information sent by a base station, and determining a first path loss, where the first path loss includes an uplink path loss between the first UE and the base station, and the measurement information includes at least one or any combination of the following: a common reference signal CRS and a channel state information reference signal CSI-RS; and determining a first power value according to the first open loop power control signaling and the first path loss.

Further, on the basis of the foregoing embodiment, the first obtaining module 101 is specifically configured to obtain the value according to P_Celluar，c(i)＝10log10(M_D2D，c(i))+P_{O_Celluar，c}+α_Celluar，c·PL_Celluar，cObtaining the first power value P of the first UE on cell c, subframe i_Celluar，c(i) Wherein M is_D2D，c(i) Denotes the number of resource blocks RB, P, used for the transmission of physical channels in cell c, sub-frame i_{O_Celluar，c}A first target received power representing the physical channel on cell c, the physical channel comprising: a physical sideline control channel PSCCH or a physical sideline shared channel PSSCH or a physical sideline discovery channel PSDCH.

Further, on the basis of the foregoing embodiment, the second obtaining module 102 is specifically configured to obtain a second type of open-loop power control signaling sent by a base station, where the second type of open-loop power control signaling includes any one of or a combination of the following: a second target power parameter, a second path loss compensation factor parameter; acquiring parameter response information sent by the second UE, and determining second path loss, wherein the second path loss comprises the path loss of a D2D communication link between the first UE and the second UE, and the parameter response information comprises at least any one or combination of a channel Sounding Reference Signal (SRS), a demodulation reference signal (DMRS), an Acknowledgement Character (ACK) and a Negative Acknowledgement (NACK); and determining a second power value according to the second type of open loop power control signaling and the second path loss.

Further, on the basis of the foregoing embodiment, the second obtaining module 102 is specifically configured to obtain the following formula:

P_D2D，c(i)＝10log₁₀(M_D2D，c(i))+P_{O_D2D，c}+α_D2D，c·PL_D2D，c，

obtaining the second power value P_D2D，c(i) Wherein the second target power parameter P_{O_D2D，c}Is the D2D target received power, α, in the D2D link on carrier c_D2D，cIs the second path loss compensation factor. PL_D2D，cIs the second path loss of the D2D communication link between the first UE and the second UE.

Further, on the basis of the foregoing embodiment, the second obtaining module 102 is further configured to obtain a second type of closed-loop power control signaling, where the second type of closed-loop power control signaling includes any one of or a combination of the following: a first parameter, a second parameter, the first parameter being a closed loop power control adjustment configured by the first UE, the second parameter being a D2D MCS related quantity configured by the first UE; and determining a second power value according to the second type of open-loop power control signaling, the second path loss and the second type of closed-loop power control signaling.

Further, on the basis of the foregoing embodiment, the second obtaining module 102 is specifically configured to obtain the following formula:

P_D2D，c(i)＝10log₁₀(M_D2D，c(i))+P_{O_D2D，c}+α_D2D，c·PL_D2D，c+Δ_{TF_D2D，c}(i)+f_D2D，c(i)

obtaining the second power value P_D2D，c(i) Wherein the second target power parameter P_{O_D2D，c}Is the D2D target received power, α, in the D2D link on carrier c_D2D，cIs the second path loss compensation factor. PL_D2D，cIs a path loss estimate for a unicast D2D link between the first UE and the second UE, the second parameter Δ_{TF_D2D，c}(i) Is a quantity related to a device-to-device modulation and coding scheme D2D MCS, and the first parameter f_D2D，c(i) Is the closed loop power control adjustment.

Further, on the basis of the foregoing embodiment, the determining module 103 is specifically configured to compare the first power value and the second power value, and determine that the minimum value is the first output power; determining a second output power according to the first output power and the second closed-loop power control signaling; and comparing the second output power with the third power value, and determining the minimum value as the output power.

Further, on the basis of the foregoing embodiment, the determining module 103 is specifically configured to sum the first output power and the first parameter to obtain the second output power; or, summing the first output power and the second parameter to obtain the second output power; or summing the first output power, the first parameter and the second parameter to obtain the second output power.

In this embodiment, the determination of the output power of the data sent by the first UE to the second UE is achieved, and therefore, it is ensured that the interference power of the first UE to the base station does not exceed the first target power value configured by the RRC signaling of the base station without affecting the communication performance of D2D.

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

Claims (18)

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

a first User Equipment (UE) acquires a first power value, wherein the first power value comprises a maximum standard power value of data sent by the first UE, and the maximum standard power value comprises a first target power value which is smaller than or equal to a power value of the first UE and is received by a base station when the first UE sends data by adopting the maximum standard power value;

the first UE obtaining a second power value, the second power value comprising a power value at which the first UE communicates with a second UE for device-to-device D2D;

and the first UE compares the first power value, the second power value and a third power value, and determines that the minimum power value is the output power of the first UE for sending data to the second UE, wherein the third power value comprises the maximum transmission power value of the first UE.

2. The method of claim 1, wherein obtaining the first power value by the first UE comprises:

the first UE acquires a first type of open-loop power control signaling sent by a base station, wherein the first type of open-loop power control signaling comprises any one or a combination of the following: a first target power parameter, a first path loss compensation factor parameter;

the first UE obtains measurement information sent by a base station, and determines a first path loss, where the first path loss includes an uplink path loss between the first UE and the base station, and the measurement information includes at least one or any combination of the following: a common reference signal CRS and a channel state information reference signal CSI-RS;

and the first UE determines a first power value according to the first type of open loop power control signaling and the first path loss.

3. The method of claim 2, wherein the first UE determines a first power value according to the first type of open loop power control signaling and the first path loss, and comprises:

the first UE is according to P_Celluar，c(i)＝10log10(M_D2D，c(i))+P_{O_Celluar，c}+α_Celluar，c·PL_Celluar，cObtaining the first power value P of the first UE on cell c, subframe i_Celluae，c(i) Wherein M is_D2D，c(i) Denotes the number of resource blocks RB, P, used for the transmission of physical channels in cell c, sub-frame i_{O_Celluar，c}Representing a first target received power of said physical channel on cell c, α_Celluar，cA first path loss compensation factor representing said physical channel on cell c, said physical channel comprising: a physical sideline control channel PSCCH or a physical sideline shared channel PSSCH or a physical sideline discovery channel PSDCH.

4. The method of any of claims 1-3, wherein obtaining the second power value by the first UE comprises:

the first UE acquires a second type of open loop power control signaling sent by a base station, wherein the second type of open loop power control signaling comprises any one or a combination of the following: a second target power parameter, a second path loss compensation factor parameter;

the first UE acquires parameter response information sent by the second UE, determines a second path loss, wherein the second path loss comprises the path loss of a D2D communication link between the first UE and the second UE, and the parameter response information comprises at least any one or the combination of a channel Sounding Reference Signal (SRS), a demodulation reference signal (DMRS), a confirmation character (ACK) and a Negative Acknowledgement (NACK);

and the first UE determines a second power value according to the second type of open loop power control signaling and the second path loss.

5. The method of claim 4, wherein the determining, by the first UE, a second power value according to the second type of open loop power control signaling and the second path loss comprises:

the first UE is according to the following formula:

P_D2D，c(i)＝10log₁₀(M_D2D，c(i))+P_{O_D2D，c}+α_D2D，c·P_LD2D，c，

obtaining the second power value P_D2D，c(i) Wherein the second target power parameter P_{O_D2D，c}Is the D2D target received power, α, in the D2D link on carrier c_D2D，cIs a second path loss compensation factor, PL_D2D，cIs the second path loss of the D2D communication link between the first UE and the second UE.

6. The method of claim 4, wherein after the first UE acquires the second type of open-loop power control signaling sent by the base station, the method further comprises:

the first UE acquires a second type of closed-loop power control signaling, wherein the second type of closed-loop power control signaling comprises any one or a combination of the following: a first parameter and a second parameter, where the first parameter is a closed-loop power control adjustment configured by the first UE, and the second parameter is a quantity configured by the first UE and related to a device-to-device modulation and coding scheme D2D MCS;

the first UE determines a second power value according to the second type of open-loop power control signaling and the second path loss, including:

and the first UE determines a second power value according to the second type of open-loop power control signaling, the second path loss and the second type of closed-loop power control signaling.

7. The method of claim 6, wherein the determining, by the first UE, a second power value according to the second type of open-loop power control signaling, the second path loss, and the second type of closed-loop power control signaling comprises:

the first UE is according to the following formula:

P_D2D，c(i)＝10log₁₀(M_D2D，c(i))+P_{O_D2D，c}+α_D2D，c·PL_D2D，c+Δ_{TF_D2D，c}(i)+f_D2D，c(i)

obtaining the second power value P_D2D，c(i) Wherein the second target power parameter P_{O_D2D，c}Is the D2D target received power, α, in the D2D link on carrier c_D2D，cIs a second path loss compensation factor, PL_D2D，cIs a path loss estimate for a unicast D2D link between the first UE and the second UE, the second parameter Δ_{TF_D2D，c}(i) Is a quantity related to the D2D MCS, the first parameter f_D2D，c(i) Is the closed loop power control adjustment.

8. The method of claim 5, wherein the first UE compares the first power value, the second power value, and a third power value, and wherein determining a minimum power is an output power for the first UE to send data to the second UE, and wherein the third power value comprises a maximum transmit power value for the first UE comprises:

the first UE compares the first power value with the second power value, and determines that the minimum value is first output power;

the first UE determines a second output power according to the first output power and the second closed-loop power control signaling;

and the first UE compares the second output power with the third power value and determines the minimum value as the output power.

9. The method of claim 8, wherein the determining, by the first UE, a second output power according to the first output power and the second type of closed loop power control signaling comprises:

the first UE sums the first output power with the first parameter to obtain the second output power; or

The first UE sums the first output power and the second parameter to obtain the second output power; or

And the first UE sums the first output power, the first parameter and the second parameter to obtain the second output power.

10. A device-to-device communication apparatus, comprising:

a first obtaining module, configured to obtain a first power value, where the first power value includes a maximum standard power value of data sent by the first UE, and the maximum standard power value includes a first target power value configured by a base station RRC signaling when the first UE sends data by using the maximum standard power value, where the power value received by the base station is smaller than or equal to the power value of the first UE;

a second obtaining module, configured to obtain a second power value, where the second power value includes a power value for the first UE to perform device-to-device D2D communication with a second UE;

a determining module, configured to compare the first power value, the second power value, and a third power value, and determine that a minimum power is an output power of the first UE for sending data to the second UE, where the third power value includes a maximum transmission power value of the first UE.

11. The apparatus of claim 10, wherein the first obtaining module is specifically configured to obtain, by the first UE, a first type of open-loop power control signaling sent by a base station, where the first type of open-loop power control signaling includes any one of or a combination of the following: a first target power parameter, a first path loss compensation factor parameter; obtaining measurement information sent by a base station, and determining a first path loss, where the first path loss includes an uplink path loss between the first UE and the base station, and the measurement information includes at least one or any combination of the following: a common reference signal CRS and a channel state information reference signal CSI-RS; and determining a first power value according to the first open loop power control signaling and the first path loss.

12. The apparatus according to claim 11, wherein the first obtaining module is specifically configured to obtain the P-based information_Celluar，c(i)＝10log10(N_D2D，c(i))+P_{O_Celluar，c}+α_Celluar，c·PL_Celluar，cObtaining the first power value P of the first UE on cell c, subframe i_Celluar，c(i) Wherein M is_D2D,c(i) Denotes the number of resource blocks RB, P, used for the transmission of physical channels in cell c, sub-frame i_{O_Celluar，c}Representing a first target received power of said physical channel on cell c, α_Celluar，cA first path loss compensation factor representing said physical channel on cell c, said physical channel comprising: physical side-path control channelPSCCH or physical side path shared channel PSCCH or physical side path discovery channel PSDCH.

13. The apparatus according to any one of claims 10 to 12, wherein the second obtaining module is specifically configured to obtain a second type of open loop power control signaling sent by a base station, where the second type of open loop power control signaling includes any one of or a combination of the following: a second target power parameter, a second path loss compensation factor parameter; acquiring parameter response information sent by the second UE, and determining second path loss, wherein the second path loss comprises the path loss of a D2D communication link between the first UE and the second UE, and the parameter response information comprises at least any one or combination of a channel Sounding Reference Signal (SRS), a demodulation reference signal (DMRS), an Acknowledgement Character (ACK) and a Negative Acknowledgement (NACK); and determining a second power value according to the second type of open loop power control signaling and the second path loss.

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

P_D2D，c(i)＝10log₁₀(M_D2D，c(i))+P_{O_D2D，c}+α_D2D，c·PL_D2D，c，

obtaining the second power value P_D2D，c(i) Wherein the second target power parameter P_{O_D2D，c}Is the D2D target received power, α, in the D2D link on carrier c_D2D，cIs a second path loss compensation factor, PL_D2D，cIs the second path loss of the D2D communication link between the first UE and the second UE.

15. The apparatus of claim 12, wherein the second obtaining module is further configured to obtain a second type of closed loop power control signaling, and the second type of closed loop power control signaling includes any one or a combination of the following: a first parameter and a second parameter, where the first parameter is a closed-loop power control adjustment configured by the first UE, and the second parameter is a quantity configured by the first UE and related to a device-to-device modulation and coding scheme D2D MCS; and determining a second power value according to the second type of open-loop power control signaling, the second path loss and the second type of closed-loop power control signaling.

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

P_D2D，c(i)＝10log₁₀(M_D2D，c(i))+P_{O_D2D，c}+α_D2D，c·PL_D2D，c+Δ_{TF_D2D，c}(i)+f_D2D，c(i)；

wherein, P_D2D，c(i) For the second power value, a second target power parameter P_{O_D2D，c}Is the D2D target received power, α, in the D2D link on carrier c_D2D，cIs a second path loss compensation factor, PL_D2D，cIs a path loss estimate for a unicast D2D link between the first UE and the second UE, the second parameter Δ_{TF_D2D，c}(i) Is a quantity related to a device-to-device modulation and coding scheme D2D MCS, and the first parameter f_D2D，c(i) Is the closed loop power control adjustment.

17. The apparatus according to claim 14, wherein the determining module is specifically configured to compare the first power value and the second power value, and determine that the minimum value is the first output power; determining a second output power according to the first output power and the second closed-loop power control signaling; and comparing the second output power with the third power value, and determining the minimum value as the output power.

18. The apparatus according to claim 17, wherein the determining module is specifically configured to sum the first output power and the first parameter to obtain the second output power; or, summing the first output power and the second parameter to obtain the second output power; or summing the first output power, the first parameter and the second parameter to obtain the second output power.