WO2017080423A1

WO2017080423A1 - D2d-based virtual mimo communication method, device and system

Info

Publication number: WO2017080423A1
Application number: PCT/CN2016/104915
Authority: WO
Inventors: 王文焕; 刘潇蔓; 杜思琪; 张锐; 王凯鹏; 刘灿; 李勇朝
Original assignee: 中兴通讯股份有限公司
Priority date: 2015-11-12
Filing date: 2016-11-07
Publication date: 2017-05-18
Also published as: CN106714248A

Abstract

Disclosed are a D2D-based virtual MIMO communication method, device and system. The method comprises: a base station establishes neighboring user equipment lists of all UEs according to information reported by all the UE in a coverage area; when receiving a request, initiated by the first UE, of communicating with the second UE, the base station determines, according to the neighboring user equipment list of the first UE and a communication mode selection strategy, communication modes adopted by the first UE and the second UE; and when determining that the first UE and the second UE adopt the D2D-based virtual MIMO communication modes, the base station determines that a cooperative user equipment of the first UE is a third UE according to a cooperative user equipment selection strategy, and configures D2D communication resources for the first UE as a sending end and the third UE as the cooperative user equipment. The present invention resolves the problem of main concentration on obtaining gain through virtual MIMO without cooperative user selection in D2D-based virtual MIMO transmission in the prior art.

Description

D2D-based virtual MIMO communication method, device and system

Technical field

The present invention relates to the field of communications, and in particular, to a device-to-device (D2D)-based multiple-input multiple-output (MIMO) communication method, apparatus, and system.

Background technique

Device-to-Device (D2D) in a Long Term Evolution (LTE) network is a short-range pass-through technology that uses licensed bands with the aid of LTE networks, which not only improves spectrum efficiency and increases system capacity. It can also reduce the base station load and reduce the transmission power. Especially when the user equipment (UE, User Equipment) is located at the edge of the cell, the revenue is more significant. The multiple-input multiple-output (MIMO) technology can obtain diversity gain and multiplexing gain through multiple antennas, and the virtual MIMO technology generated to solve the user equipment limitation realizes unified processing of geographically distributed antennas. Obtain the above gain. If the cooperative communication technology and the D2D technology are organically combined in the LTE network, that is, the service and control provided by the cellular network infrastructure such as the base station are allowed, and the virtual MIMO transmission is allowed through the D2D communication between the user equipments, and the diversity gain of the virtual MIMO can be effectively utilized. It can also break through the performance limit of existing D2D communication and further enhance D2D technology. In D2D-based virtual MIMO transmission, in order to achieve effective cooperative transmission, the first thing that needs to be solved is the choice of the collaboration partner, that is, how to select the appropriate node as the cooperative transmission partner in the set of candidate cooperative user equipment. Collaborative partner selection strategies have an important impact on overall network performance, system complexity, and system overhead. However, the prior art mainly focuses on gains obtained by virtual MIMO, and does not provide a suitable selection method for cooperative partners.

Summary of the invention

In order to solve the above technical problem, the present invention provides a D2D-based virtual MIMO communication method, apparatus, and system, which are used to solve the D2D-based virtual MIMO transmission in the prior art, mainly focusing on obtaining gain through virtual MIMO, without collaborative user selection. The problem.

In order to achieve the above technical purpose, the present invention provides a D2D-based virtual MIMO communication method, including: a base station establishes a neighbor user equipment list of each user equipment according to information reported by each user equipment in the coverage area; when the base station receives the first user When the device initiates a communication request with the second user equipment, the base station determines, according to the neighboring user equipment list of the first user equipment and the communication mode selection policy, a communication mode adopted by the first user equipment and the second user equipment; when the base station determines When the first user equipment and the second user equipment adopt the D2D-based virtual MIMO communication mode, the base station determines, according to the coordinated user equipment selection policy, that the coordinated user equipment of the first user equipment is the third user equipment, and the base station is the sender. A user equipment and a third user equipment as a cooperative user equipment configure D2D communication resources.

Further, the neighboring user equipment list of each user equipment includes: an identity identifier of each user equipment, a channel quality indicator (CQI) level between each user equipment and a base station, an identity identifier of a neighboring user equipment of each user equipment, and each user equipment and CQI level between adjacent user equipment.

Further, the determining, by the base station, the communication mode adopted by the first user equipment and the second user equipment according to the neighboring user equipment list of the first user equipment and the communication mode selection policy, including:

When the second user equipment is not located in the neighboring user equipment list of the first user equipment, the base station determines that the first user equipment and the second user equipment adopt a cellular communication mode;

When the second user equipment is located in the neighboring user equipment list of the first user equipment, and the CQI level between the first user equipment and the second user equipment is greater than a preset parameter, the base station determines the first user equipment And adopting a D2D communication mode with the second user equipment;

When the second user equipment is located in the neighboring user equipment list of the first user equipment, and the CQI level between the first user equipment and the second user equipment is less than or equal to the preset parameter, the base station determines that The first user equipment and the second user equipment adopt a D2D-based virtual MIMO communication mode.

Further, the preset parameter is an average CQI level of the user equipment calculated by the base station according to a CQI level between user equipments in the neighboring user equipment list.

Further, the determining, by the base station, that the coordinated user equipment of the first user equipment is the third user equipment, according to the coordinated user equipment selection policy, includes:

Determining a revenue function u _i (t) of the neighboring user equipment i in the neighboring user equipment list of the first user equipment as the transmitting end,

among them,

When t=0, u _i (t)=0, i is an integer greater than or equal to 1, p is the power consumed by the current communication relay node, and the constant t _c =1000, indicating the sliding window length;

When there is a neighboring user equipment with a return function of 0, the transmission rate r _i (t) reachable by the user equipment with a revenue function of 0 to the second user equipment as the receiving end is estimated, and the user equipment with the highest transmission rate is selected as the user equipment a collaborative user device of the first user equipment,

Where r _i (t)=log ₂ (1+γ _i (t)), γ _i (t) is a signal to noise ratio;

When there is no neighboring user equipment with a return function of 0, the adaptive weighting coefficient ω(u _i ), the transmission rate r _i (t) of each neighboring user equipment, and the product of the adaptive weighting coefficient and the transmission rate ω (u _i ) are calculated. And r _i (t), and selecting the user equipment with the largest product as the cooperative user equipment of the first user equipment, where

r _i (t) = log ₂ (1 + γ _i (t)).

Further, the base station configures the D2D communication resource for the first user equipment that is the transmitting end and the third user equipment that is the cooperative user equipment, including:

The base station sends the first D2D scheduling information to the first user equipment that is the transmitting end, where the first D2D scheduling information includes a scheduling that the first user equipment that is the transmitting end sends the data packet to the third user equipment that is the coordinated user equipment. information;

Transmitting, by the base station, second D2D scheduling information to the first user equipment that is the transmitting end, and the third user equipment that is the coordinated user equipment, where the second D2D scheduling information includes the first user equipment that is the transmitting end and the cooperative user equipment Third user device The second user equipment at the receiving end sends scheduling information of the data packet.

The present invention also provides a D2D-based virtual MIMO communication method, including: a base station establishes a neighbor user equipment list of each user equipment according to information reported by each user equipment in the coverage area; and when the base station receives the first user equipment initiated and And determining, by the base station, the communication mode adopted by the first user equipment and the second user equipment according to the neighboring user equipment list of the first user equipment and the communication mode selection policy; and determining, by the base station, the first user equipment When the second user equipment adopts the D2D-based virtual MIMO communication mode, the base station determines, according to the coordinated user equipment selection policy, that the coordinated user equipment of the first user equipment is the third user equipment, and serves as the first user equipment as the transmitting end and cooperates. The third user equipment of the user equipment configures the D2D communication resource; the first user equipment that is the transmitting end sends the data packet and the control information to the third user equipment that is the cooperative user equipment, where the control information is the first user equipment that is the sending end. Send to a third user device that is a collaborative user device Scheduling information of the data packet; transmitting end as a first user device and a third device collaborating users as a user of the apparatus according to the D2D communication resource configured by the BS cooperative space-time coding transmission data packet to the second user as a receiving end device.

The present invention further provides a D2D-based virtual MIMO communication device, which is applied to a base station, and includes: a neighboring user equipment list establishing module, configured to establish a neighbor user equipment list of each user equipment according to information reported by each user equipment in the coverage area; a communication mode selection module, configured to: when the base station receives a communication request initiated by the first user equipment with the second user equipment, determine the first user according to the neighboring user equipment list of the first user equipment and a communication mode selection policy a communication mode adopted by the device and the second user equipment; the processing module is configured to: when the communication mode selection module determines that the first user equipment and the second user equipment adopt a D2D-based virtual MIMO communication mode, according to the cooperative user equipment The selection policy determines that the coordinated user equipment of the first user equipment is the third user equipment, and configures the D2D communication resource for the first user equipment that is the transmitting end and the third user equipment that is the coordinated user equipment.

Further, the neighboring user equipment list of each user equipment includes: an identity identifier of each user equipment, a CQI level between each user equipment and a base station, an identity identifier of a neighboring user equipment of each user equipment, and between each user equipment and a neighboring user equipment. CQI rating.

Further, the communication mode selection module is configured to be based on the neighbor of the first user equipment The user equipment list and the communication mode selection policy determine a communication mode adopted by the first user equipment and the second user equipment, including:

Determining that the first user equipment and the second user equipment adopt a cellular communication mode when the second user equipment is not located in the neighboring user equipment list of the first user equipment;

Determining the first user equipment and the first user equipment when the second user equipment is located in the neighboring user equipment list of the first user equipment, and the CQI level between the first user equipment and the second user equipment is greater than a preset parameter The second user equipment adopts a D2D communication mode;

Determining the first user device when the second user equipment is located in the neighboring user equipment list of the first user equipment, and the CQI level between the first user equipment and the second user equipment is less than or equal to the preset parameter. The device and the second user equipment adopt a D2D-based virtual MIMO communication mode.

Further, the processing module is configured to determine, according to the coordinated user equipment selection policy, that the coordinated user equipment of the first user equipment is the third user equipment, including:

among them,

Where r _i (t)=log ₂ (1+γ _i (t)), γ _i (t) is a signal to noise ratio;

_{_{r i (t) = log 2}} (1 + γ i (t)).

Further, the processing module is configured to configure the D2D communication resource for the first user equipment that is the transmitting end and the third user equipment that is the coordinated user equipment, including:

Sending the first D2D scheduling information to the first user equipment that is the transmitting end, where the first D2D scheduling information includes scheduling information that the first user equipment that is the transmitting end sends the data packet to the third user equipment that is the coordinated user equipment;

Transmitting second D2D scheduling information to the first user equipment as the transmitting end and the third user equipment as the cooperative user equipment, where the second D2D scheduling information includes the first user equipment as the transmitting end and the third user equipment as the cooperative user equipment The user equipment sends scheduling information of the data packet to the second user equipment that is the receiving end.

The present invention further provides a D2D-based virtual MIMO communication system, comprising: the base station and the user equipment as described above; wherein the first user equipment as the transmitting end is configured to send the data packet to the third user equipment as the cooperative user equipment And control information, wherein the control information is scheduling information that the first user equipment that is the transmitting end sends a data packet to the third user equipment that is the coordinated user equipment; the first user equipment that is the transmitting end and the third that is the coordinated user equipment And the user equipment is configured to, according to the D2D communication resource configured by the base station, jointly send the data packet to the second user equipment as the receiving end by space time coding.

In the present invention, the base station establishes a list of neighboring user equipments of each user equipment according to the information reported by each user equipment in the coverage area; when the base station receives the communication request initiated by the first user equipment with the second user equipment, the base station according to the The neighboring user equipment list of the first user equipment and the communication mode selection policy determine a communication mode adopted by the first user equipment and the second user equipment; when the base station determines that the first user equipment and the second user equipment adopt D2D-based virtual In the MIMO communication mode, the base station determines that the coordinated user equipment of the first user equipment is the third user equipment according to the coordinated user equipment selection policy, and the base station configures the D2D communication for the first user equipment that is the transmitting end and the third user equipment that is the cooperative user equipment. Resources. In the D2D-based virtual MIMO communication provided by the present invention, a cooperative user equipment is selected for a user equipment as a transmitting end.

Further, in the process of selecting the collaborative user equipment, by calculating a revenue function that comprehensively considers the transmission rate and the fairness of the user equipment, the user equipment as the transmitting end selects a suitable cooperative user equipment to complete the transmission. Thus, with the present invention, an adaptive weighting coefficient is obtained by dynamically establishing a "gain function" by using the accumulated power consumed by the cooperative user equipment to dynamically adjust the priority of each user equipment, while ensuring that the system achieves a relatively high fairness. Thus ensuring that the fairness of the system has been maintained at a relatively high level. At the same time, the cooperative user equipment selection policy takes into account the channel capacity, and selects an alternate user equipment with a better link status with the destination user equipment when pairing the user equipment, and only needs to cooperate between the user equipment and the destination user equipment. Link information requires less information and less complexity.

DRAWINGS

FIG. 1 is a flowchart of a D2D-based virtual MIMO communication method according to an embodiment of the present invention;

2 is a schematic diagram of an application scenario according to an embodiment of the present invention;

3 is a flowchart of a collaborative user equipment selection process according to an embodiment of the present invention;

FIG. 4 is a schematic diagram of a D2D-based virtual MIMO communication apparatus according to an embodiment of the present invention.

detailed description

The embodiments of the present invention are described in detail below with reference to the accompanying drawings.

FIG. 1 is a flowchart of a D2D-based virtual MIMO communication method according to an embodiment of the present invention. As shown in FIG. 1 , the D2D-based virtual MIMO communication method provided in this embodiment includes the following steps:

Step 101: The base station establishes a neighbor user equipment list of each user equipment according to the information reported by each user equipment in the coverage area.

The neighboring user equipment list of each user equipment includes: an identity identifier of each user equipment, A channel quality indicator (CQI) level between each user equipment and a base station, an identity of a neighboring user equipment of each user equipment, and a CQI level between each user equipment and a neighboring user equipment.

Specifically, after the user equipment enters the cell, the user equipment synchronizes with the base station through the Uu interface; the base station periodically establishes contact with each user equipment to obtain channel state information between the user equipment and the base station; and the user equipment finds the neighbor according to the D2D user equipment discovery rule. The user equipment is reported to the base station, and the base station establishes a list of neighboring user equipments of each user equipment.

Step 102: When the base station receives the communication request initiated by the first user equipment and the second user equipment, the base station determines the first user equipment and the second according to the neighboring user equipment list of the first user equipment and the communication mode selection policy. The communication mode adopted by the user equipment.

The determining, by the base station, the communication mode adopted by the first user equipment and the second user equipment according to the neighboring user equipment list of the first user equipment and the communication mode selection policy, including:

When the second user equipment is located in the neighboring user equipment list of the first user equipment, and the CQI level between the first user equipment and the second user equipment is greater than a preset parameter, the base station determines the first user equipment and the The second user equipment adopts a D2D communication mode;

When the second user equipment is located in the neighboring user equipment list of the first user equipment, and the CQI level between the first user equipment and the second user equipment is less than or equal to the preset parameter, the base station determines the first The user equipment and the second user equipment adopt a D2D-based virtual MIMO communication mode.

In an embodiment, the preset parameter is a user equipment average CQI level calculated by the base station according to a CQI level between each user equipment in the neighboring user equipment list.

Specifically, when the base station determines that the first user equipment and the second user equipment adopt the D2D communication mode, the base station calculates a minimum transmit power according to the CQI level in the neighboring user equipment list; after that, the base station is in the cellular user equipment that is communicating. A user equipment is selected as a multiplexing object of D2D communication, and the selection criterion of the multiplexing object is interference and minimum principle. Then, the interference and the smallest cellular user equipment are selected as resource multiplexing objects for communication.

Step 103: When the base station determines that the first user equipment and the second user equipment adopt a D2D-based virtual MIMO communication mode, the base station determines, according to the coordinated user equipment selection policy, that the coordinated user equipment of the first user equipment is the third user equipment, and The base station configures a D2D communication resource for the first user equipment as the transmitting end and the third user equipment as the cooperative user equipment.

The determining, by the base station, the coordinated user equipment of the first user equipment is the third user equipment according to the coordinated user equipment selection policy, including:

among them,

Where r _i (t)=log ₂ (1+γ _i (t)), γ _i (t) is a signal to noise ratio;

_{_{r i (t) = log 2}} (1 + γ i (t)).

The base station configures the D2D communication resource for the first user equipment that is the transmitting end and the third user equipment that is the coordinated user equipment, including:

The base station to the first user equipment as the transmitting end and the first as the cooperative user equipment The third user equipment sends the second D2D scheduling information, where the second D2D scheduling information includes a scheduling of the first user equipment that is the transmitting end and the third user equipment that is the coordinated user equipment sends the data packet to the second user equipment that is the receiving end. information.

In addition, the embodiment of the present invention further provides a D2D-based virtual MIMO communication method, including:

The base station establishes a list of neighboring user equipments of each user equipment according to the information reported by each user equipment in the coverage area;

When the base station receives the communication request with the second user equipment initiated by the first user equipment, the base station determines, according to the neighbor user equipment list of the first user equipment, and the communication mode selection policy, that the first user equipment and the second user equipment are used. Communication mode

When the base station determines that the first user equipment and the second user equipment adopt a D2D-based virtual MIMO communication mode, the base station determines, according to the coordinated user equipment selection policy, that the coordinated user equipment of the first user equipment is the third user equipment, and sends the Configuring a D2D communication resource by the first user equipment of the terminal and the third user equipment that is the collaborative user equipment;

The first user equipment that is the transmitting end sends the data packet and the control information to the third user equipment that is the cooperative user equipment, where the control information is that the first user equipment that is the sending end sends data to the third user equipment that is the collaborative user equipment. Packet scheduling information;

The first user equipment as the transmitting end and the third user equipment as the cooperative user equipment jointly transmit the data packet to the second user equipment as the receiving end by space-time coding according to the D2D communication resource configured by the base station.

Specifically, when the base station determines that the first user equipment and the second user equipment adopt a cellular communication mode or a D2D communication mode, the base station performs coding, modulation, reception, detection, and the like according to the traditional cellular communication mode; when the base station determines the first user equipment and the first The user equipment that is the transmitting end first sends the data packet and the control information to the coordinated user equipment, and then the user equipment and the coordinated user equipment that are the transmitting end jointly pass the space time on the scheduled resource. The packet coding cooperatively transmits a data packet to the user equipment as the receiving end. The control information is scheduling information that the user equipment that is the transmitting end sends the data packet to the cooperative user equipment.

The invention is illustrated by the following specific examples.

The network scenario used in this embodiment is shown in FIG. 2. In a single cell, a total of M user equipments are within the coverage of the base station, and gi _j (i=1...M, j=1...M) represents the channel gain between user equipments (UEs), h _j (j=1 ...M) represents the channel gain between the user equipment and the base station. Where M is an integer greater than one. D2D communication and D2D-based virtual MIMO communication multiplex cellular uplink resources. At the current time, UE1 and UE2 perform cellular communication with the base station. At this time, there is a need for communication between UE3 and UE4. This embodiment will be described in detail by the following steps.

Step S1: After the user equipment enters the cell, the user equipment synchronizes with the base station through the Uu interface. The base station periodically establishes contact with each user equipment to obtain channel state information between the user equipment and the base station.

Specifically, when the UE1 joins the network, the UE1 searches for a Primary Synchronization Signal (PSS), selects a cell that the UE1 considers to be the best, implements symbol synchronization, and searches for a secondary synchronization signal according to the primary synchronization signal (SSS, Secondary Synchronization). Signal), realizes frame synchronization; after synchronization is implemented, UE1 obtains system information (such as system bandwidth, uplink and downlink configuration information, random access channel (RACH) parameters, power control parameters) through a broadcast channel (BCH, Broadcast Channel). After acquiring the cell information, the UE1 establishes a link with the cell through the random access procedure; the UE1 periodically reports the channel state information (CSI, Channel State Information) to the base station.

Step S2: After the network is synchronized, the user equipment performs periodic neighboring user equipment discovery, and each user equipment periodically uploads detection information of the neighboring user equipments, and the base station forms a neighboring user equipment list of each user equipment.

Specifically, the base station allocates an initial time-frequency resource block for neighboring user equipment discovery to the new network access user equipment, and jumps according to the rule in a subsequent period;

If the UE1 detects the neighboring user equipment discovery signal of the user equipment such as the UE2 on the discovery resource configured by the base station, the UE1 determines whether it satisfies the D2D communication requirement according to the signal to noise ratio (SNR) of the received signal, where the D2D is satisfied. The condition required for communication is the SNR threshold. If the condition is met, the result is found according to the channel quality between the user equipments. The CQI level information between the user equipments generated by the source is uploaded to the base station through the uplink channel; wherein the CQI quantization standard is as shown in Table 1;

Table 1 CQI Quantification Standard

The base station forms a list of neighboring user equipments including CQI levels between user equipments according to the report result of the user equipment, and stores the information in the base station, and the format thereof is as shown in Table 2. The neighboring user equipment list includes: each user equipment identity, a CQI level between each user equipment and a base station, an identity of a neighboring user equipment of each user equipment, and between each user equipment and its neighboring user equipment. CQI rating.

Table 2 List of neighboring user devices

The user equipment periodically uploads its own measurement information to update the neighboring user equipment list. The base station obtains a list of neighboring user equipments of the entire network. After the base station learns the channel quality CQI level between the user equipments, the base station calculates the average CQI level of the network user equipment CQI _ave. .

Step S3: The UE3 initiates a communication request to the base station, and the destination user is the UE4.

Step S4: The base station determines a communication mode between the UE 3 and the UE 4.

Specifically, after receiving the communication request of the UE3, the base station first searches for the neighboring user equipment list of the UE3. If the UE4 is not located in the neighboring user equipment list of the UE3, it is determined that the UE3 and the UE4 adopt a cellular communication mode; if the UE4 is located in the UE3, The neighboring user equipment list determines whether the CQI level CQI ₃₄ between the UE3 and the UE4 satisfies the communication requirement between the two. For example, if the CQI ₃₄ > CQI _ave , the UE3 and the UE 4 adopt the D2D communication mode; otherwise, the CQI ₃₄ <= CQI _ave, the UE3 and UE4 based virtual MIMO communication mode of D2D.

Step S5: After the base station determines the communication mode between the UE3 and the UE4, allocate the following communication resources to the UE3 and the UE4: the time-frequency resource block, the transmit power (and the coordinated user equipment).

Specifically, when the UE3 and UE4 uses the cellular communication mode, the base station allocates orthogonal to the upper and lower rows of idle frequency resource block UE3 and UE4, meeting quality of service (QoS h ₃ and h ₄ according to Calculation UE3 and UE4, Quality of Service) minimum transmit power required, and through the closed-loop power control method, transmit power adjustment;

When the D2D communication mode is adopted between the UE3 and the UE4, the base station calculates a minimum transmit power according to the CQI level in the neighboring user equipment list, and the base station configures the D2D communication resource to perform communication;

When the D2D-based virtual MIMO communication is used between the UE3 and the UE4, the base station needs to separately calculate the cooperative user equipment when the UE3 and the UE4 are respectively the senders.

Here, taking UE3 as the transmitting end as an example, the base station first calculates the minimum transmit power of UE3 according to CQI ₃₄ , and uses this as the power limiting condition for performing virtual MIMO communication.

The base station selects the UEj (the UEj is an idle user equipment, that is, the user equipment without the D2D service requirement and the cellular service requirement) from the neighboring user equipment list of the UE3 as the coordinated user equipment of the sender.

Here, the selection process of the cooperative user equipment is as shown in FIG. 3. Here, the process is described with reference to FIG. 3 by taking UE3 as an example:

Step 301: Initialize a "return function" u _i (t), (t=0, i=1, 2, . . . , n) is 0, where u _i (t) represents a list of neighboring user equipments of UE3 a revenue function adjacent to user equipment i;

Step 302: The base station receives the cooperative communication request initiated by the UE3.

Step 303: Perform a screening, that is, judge the “return function” u _i (t) of each user equipment (the candidate user equipment set U) in the neighboring user equipment list of the UE3, if there is a u _i (t) equal to 0 If the user equipment is in step 304, the user equipment is placed in the set U ₀ of the screening, and then step 305 is performed. Otherwise, the user equipment of the candidate user equipment set U does not have a revenue function of 0. Go to step 307;

Step 305: Each user equipment in the set U ₀ of the primary screening estimates the transmission rate r _i (t)=log ₂ that the user equipment can reach to the destination user equipment (here, such as UE4) according to the channel estimation situation. 1+γ _i (t)), where γ _i (t) is a signal to noise ratio, and then, in step 306, the user equipment with the largest r _i (t) is selected as the coordinated user equipment of UE3;

The user equipment J represents the maximum signal to noise ratio of the user equipment device in a destination user set U _0, where, γ _i (t) is a set of user devices U ₀ in the signal to noise ratio of the destination user equipment;

Step 307: Calculate a transmission rate r _i (t) of each user equipment in the candidate user equipment set U;

Step 308: Calculate adaptive weighting coefficients of each user equipment in the set of candidate user equipment U

And multiplying by the estimated transmission rate r _i (t) of the user equipment to obtain ω(u _i )r _i (t);

Step 309: Select a user equipment with the largest ω(u _i )r _i (t) as the coordinated user equipment of the UE3;

Step 310: Update the "revenue function" u _i (t), where

Where p is the power consumed by the communication relay node, and the constant t _c = 1000, indicating the length of the sliding window.

Thereafter, the base station calculates the minimum transmit power of UE3 and UEj through CQI _{3j, and} calculates the transmit power when UE3 and UEj transmit signals to UE4 in combination with the power limit obtained above. The D2D communication resource is configured to perform communication at the base station, that is, 1) the base station sends D2D scheduling information to the UE3, where the D2D scheduling information includes the time-frequency resource that the UE3 sends the data packet to the UEj; 2) the base station sends the D2D scheduling information to the UE3 and the UEj, the D2D The scheduling information includes a time-frequency resource in which the UE3 and the UEj cooperatively transmit a data packet to the UE4.

Step S6: Perform transmission.

Specifically, if UE3 and UE4 adopt a cellular communication or D2D communication mode, encoding, modulating, receiving, detecting, etc. are performed according to a conventional cellular communication mode;

If UE3 and UE4 adopt a D2D-based virtual MIMO communication mode, UE3 first sends a data packet and control information to UEj, where the control information is scheduling information that UE3 sends a data packet to UEj.

The space-time coding is performed on the UE3 as the transmitting end and the UEj as the cooperative user equipment. The specific coding rules are as shown in Table 3:

Table 3 Distributed Alamouti Encoding Rules

Where * indicates conjugate.

Here, UE4 receives the following two signals:

Where x _k represents data transmitted by the user equipment U _k (here, x ₃ represents data transmitted by the UE ₃ , x _j represents data transmitted by the UE _j ), and z _ij represents a link between the user equipment U _i and the user equipment U _j Gaussian white noise (here, z ₃₄ represents Gaussian white noise of the link between UE3 and UE4, z _j4 represents Gaussian white noise of the link between UEj and UE4), and P denotes a transmitting end and a cooperative user equipment (here, and UE3 is UEj) combined transmission power of the transmission, the base station is calculated based on the second hop power value CQI ₃₄ step S5, I _c represents the interference due to the communication resource reuse cellular user brings, g _ij represents between user devices Channel gain (here, g ₃₄ represents the channel gain between UE3 and UE4, and g _j4 represents the channel gain between UEj and UE4).

FIG. 4 is a schematic diagram of a D2D-based virtual MIMO communication apparatus according to an embodiment of the present invention. As shown in FIG. 4, the D2D-based virtual MIMO communication device provided in this embodiment is applied to a base station, and includes: a neighboring user equipment list establishing module 401, a communication mode selection module 402, and a processing module 403.

The neighboring user equipment list establishing module 401 is configured to establish a neighboring user equipment list of each user equipment according to the information reported by each user equipment in the coverage area; the communication mode selection module 402 is configured to: when the base station receives the first user equipment, Determining a communication mode adopted by the first user device and the second user device according to the neighboring user device list of the first user device and the communication mode selection policy; the processing module 403 is configured to When the communication mode selection module 402 determines that the first user equipment and the second user equipment adopt a D2D-based virtual MIMO communication mode, determining, according to the coordinated user equipment selection policy, that the coordinated user equipment of the first user equipment is the third user equipment And configuring a D2D communication resource for the first user equipment as the transmitting end and the third user equipment as the cooperative user equipment.

The neighboring user equipment list of each user equipment includes: an identity identifier of each user equipment, a CQI level between each user equipment and a base station, an identity identifier of a neighboring user equipment of each user equipment, and a CQI between each user equipment and a neighboring user equipment. grade.

Further, the communication mode selection module 402 is configured to determine, according to the neighboring user equipment list of the first user equipment, and the communication mode selection policy, the communication mode adopted by the first user equipment and the second user equipment, including:

Further, the processing module 403 is configured to determine, according to the coordinated user equipment selection policy, that the coordinated user equipment of the first user equipment is the third user equipment, including:

among them,

When there is a neighboring user equipment with a return function of 0, the user equipment whose revenue function is 0 is estimated to the transmission rate r _i (t) that can be achieved by the second user equipment as the receiving end, and the user equipment with the highest transmission rate is selected as the user equipment. a collaborative user device of the first user equipment,

Where r _i (t)=log ₂ (1+γ _i (t)), γ _i (t) is a signal to noise ratio;

r _i (t) = log ₂ (1 + γ _i (t)).

Further, the processing module 403 is configured to configure the D2D communication resource for the first user equipment that is the transmitting end and the third user equipment that is the coordinated user equipment, including:

In practical applications, the functions of the above modules are implemented by the processor executing programs/instructions stored in the memory. However, the present invention is not limited thereto. The functions of the above modules can also be implemented by firmware/logic circuits/integrated circuits.

In addition, the embodiment of the present invention further provides a D2D-based virtual MIMO communication system, including: a base station and a user equipment as shown in FIG. 4; wherein, the first user equipment, which is the transmitting end, is set to be the first user equipment. The third user equipment sends the data packet and the control information, where the control information is the scheduling information that the first user equipment that is the transmitting end sends the data packet to the third user equipment that is the coordinated user equipment; the first user equipment that serves as the sending end and the The third user equipment of the cooperative user equipment is configured to jointly send the data packet to the second user equipment as the receiving end by space-time coding according to the D2D communication resource configured by the base station.

In addition, the specific processing flow of the above device and system is the same as the above method, so it is no longer Narration.

In summary, after the user equipment completes the synchronization and initialization of the network, the user equipment provides the user equipment identity and the link quality for the subsequent communication mode selection and the coordinated user equipment selection. After acquiring the channel state information between the user equipments, the base station performs communication mode selection and resource allocation for the user equipments with communication requirements. For the user equipment adopting the virtual MIMO-D2D communication mode, the user can select the appropriate cooperative user equipment to complete the transmission by calculating the revenue function considering the transmission rate and the user fairness, and improve the system fairness while ensuring the channel capacity. Efficient D2D-based virtual MIMO transmission.

The basic principles and main features of the present invention and the advantages of the present invention are shown and described above. The present invention is not limited by the above-described embodiments, and the above-described embodiments and the description are merely illustrative of the principles of the present invention, and various changes and modifications may be made without departing from the spirit and scope of the invention. And modifications are intended to fall within the scope of the invention as claimed.

Industrial applicability

As described above, the D2D-based virtual MIMO communication method, apparatus, and system provided by the embodiments of the present invention have the following beneficial effects: by ensuring that the system achieves relatively high fairness, the accumulated power consumption is established by using the cooperative user equipment. The "return function" obtains an adaptive weighting factor to dynamically adjust the priority of each user equipment, thereby ensuring that the fairness of the system is maintained at a relatively high level. At the same time, the cooperative user equipment selection policy takes into account the channel capacity, and selects an alternate user equipment with a better link status with the destination user equipment when pairing the user equipment, and only needs to cooperate between the user equipment and the destination user equipment. Link information requires less information and less complexity.

Claims

A device-to-device D2D virtual multiple input multiple output MIMO communication method, comprising:

The base station establishes a list of neighboring user equipments of each user equipment according to the information reported by the UEs of the user equipments in the coverage area;

When the base station receives the communication request initiated by the first user equipment with the second user equipment, the base station determines, according to the neighboring user equipment list of the first user equipment, and the communication mode selection policy, the first user equipment and the first The communication mode adopted by the two user equipments;

When the base station determines that the first user equipment and the second user equipment adopt a D2D-based virtual MIMO communication mode, the base station determines, according to the coordinated user equipment selection policy, that the coordinated user equipment of the first user equipment is the third user equipment, And the base station configures a D2D communication resource for the first user equipment that is the transmitting end and the third user equipment that is the coordinated user equipment.
The method of claim 1, wherein the neighboring user equipment list of each user equipment comprises: an identity of each user equipment, a channel quality indication CQI level between each user equipment and a base station, and an identity of a neighboring user equipment of each user equipment. Identification and CQI level between each user equipment and neighboring user equipment.
The method of claim 1, wherein the determining, by the base station, the communication mode adopted by the first user equipment and the second user equipment according to the neighboring user equipment list of the first user equipment and the communication mode selection policy, including:

When the second user equipment is not located in the neighboring user equipment list of the first user equipment, the base station determines that the first user equipment and the second user equipment adopt a cellular communication mode;

When the second user equipment is located in the neighboring user equipment list of the first user equipment, and the CQI level between the first user equipment and the second user equipment is greater than a preset parameter, the base station determines the first user equipment And adopting a D2D communication mode with the second user equipment;

When the second user equipment is located in the neighboring user equipment list of the first user equipment, and the CQI level between the first user equipment and the second user equipment is less than or equal to the preset parameter. The base station determines that the first user equipment and the second user equipment adopt a D2D-based virtual MIMO communication mode.
The method according to claim 3, wherein the preset parameter is a user equipment average CQI level calculated by the base station according to a CQI level between user equipments in a neighboring user equipment list.
The method of claim 1, wherein the determining, by the base station, the coordinated user equipment of the first user equipment as the third user equipment according to the coordinated user equipment selection policy comprises:

Determining a revenue function u i (t) of the neighboring user equipment i in the neighboring user equipment list of the first user equipment as the transmitting end,

among them,
When t=0, u i (t)=0, i is an integer greater than or equal to 1, p is the power consumed by the current communication relay node, and the constant t c =1000, indicating the sliding window length;

When there is a neighboring user equipment with a return function of 0, the transmission rate r i (t) reachable by the user equipment with a revenue function of 0 to the second user equipment as the receiving end is estimated, and the user equipment with the highest transmission rate is selected as the user equipment a collaborative user device of the first user equipment,

Where r i (t)=log 2 (1+γ i (t)), γ i (t) is a signal to noise ratio;

When there is no neighboring user equipment with a return function of 0, the adaptive weighting coefficient ω(u i ), the transmission rate r i (t) of each neighboring user equipment, and the product of the adaptive weighting coefficient and the transmission rate ω (u i ) are calculated. And r i (t), and selecting the user equipment with the largest product as the cooperative user equipment of the first user equipment, where
r i (t) = log 2 (1 + γ i (t)).
The method of claim 1, wherein the base station configures the D2D communication resource for the first user equipment as the transmitting end and the third user equipment as the cooperative user equipment, including:

The base station sends the first D2D scheduling information to the first user equipment that is the transmitting end, where the first D2D scheduling information includes a scheduling that the first user equipment that is the transmitting end sends the data packet to the third user equipment that is the coordinated user equipment. Information

Transmitting, by the base station, second D2D scheduling information to the first user equipment that is the transmitting end, and the third user equipment that is the coordinated user equipment, where the second D2D scheduling information includes the first user equipment that is the transmitting end and the cooperative user equipment The third user equipment sends scheduling information of the data packet to the second user equipment that is the receiving end.
A D2D-based virtual MIMO communication method includes:

The base station establishes a list of neighboring user equipments of each user equipment according to the information reported by each user equipment in the coverage area;

When the base station receives the communication request initiated by the first user equipment with the second user equipment, the base station determines, according to the neighboring user equipment list of the first user equipment, and the communication mode selection policy, the first user equipment and the first The communication mode adopted by the two user equipments;

When the base station determines that the first user equipment and the second user equipment adopt a D2D-based virtual MIMO communication mode, the base station determines, according to the coordinated user equipment selection policy, that the coordinated user equipment of the first user equipment is the third user equipment, And configuring a D2D communication resource for the first user equipment that is the transmitting end and the third user equipment that is the coordinated user equipment;

The first user equipment that is the transmitting end sends the data packet and the control information to the third user equipment that is the cooperative user equipment, where the control information is that the first user equipment that is the sending end sends data to the third user equipment that is the collaborative user equipment. Packet scheduling information;

The first user equipment as the transmitting end and the third user equipment as the cooperative user equipment jointly transmit the data packet to the second user equipment as the receiving end by space-time coding according to the D2D communication resource configured by the base station.
A D2D-based virtual MIMO communication device is applied to a base station, including:

The neighboring user equipment list establishing module is configured to establish a neighboring user equipment list of each user equipment according to the information reported by each user equipment in the coverage area;

a communication mode selection module, configured to: when the base station receives a communication request initiated by the first user equipment with the second user equipment, determine the first user according to the neighboring user equipment list of the first user equipment and a communication mode selection policy a communication mode adopted by the device and the second user equipment;

a processing module, configured to: when the communication mode selection module determines that the first user equipment and the second user equipment adopt a D2D-based virtual MIMO communication mode, determine, according to the collaborative user equipment selection policy, that the coordinated user equipment of the first user equipment is The third user equipment configures a D2D communication resource for the first user equipment as the transmitting end and the third user equipment as the cooperative user equipment.
The device of claim 8, wherein the neighboring user equipment list of each user equipment comprises: an identity of each user equipment, a CQI level between each user equipment and a base station, an identity of a neighboring user equipment of each user equipment, and each CQI level between the user equipment and the neighboring user equipment.
The device of claim 8, wherein the communication mode selection module is configured to determine, according to the neighboring user equipment list of the first user equipment and the communication mode selection policy, the first user equipment and the second user equipment Communication mode, including:

Determining that the first user equipment and the second user equipment adopt a cellular communication mode when the second user equipment is not located in the neighboring user equipment list of the first user equipment;

Determining the first user equipment and the first user equipment when the second user equipment is located in the neighboring user equipment list of the first user equipment, and the CQI level between the first user equipment and the second user equipment is greater than a preset parameter The second user equipment adopts a D2D communication mode;

Determining the first user device when the second user equipment is located in the neighboring user equipment list of the first user equipment, and the CQI level between the first user equipment and the second user equipment is less than or equal to the preset parameter. The device and the second user equipment adopt a D2D-based virtual MIMO communication mode.
The apparatus according to claim 10, wherein the preset parameter is a user equipment average CQI level calculated by the base station according to a CQI level between user equipments in a neighboring user equipment list.
The device of claim 8, wherein the processing module is configured to determine, according to the collaborative user equipment selection policy, that the collaborative user equipment of the first user equipment is a third user equipment, including:

Determining a revenue function u i (t) of the neighboring user device i in the neighboring user equipment list of the first user equipment as the transmitting end,

among them,
When t=0, u i (t)=0, i is an integer greater than or equal to 1, p is the power consumed by the current communication relay node, and the constant t c =1000, indicating the sliding window length;

When there is a neighboring user equipment function returns 0, 0 estimated revenue function as a user equipment to a second user device receiving end can achieve transmission rates r i (t), and selects the maximum transmission rate of the user equipment as a collaborative user device of the first user equipment,

Where r i (t)=log 2 (1+γ i (t)), γ i (t) is a signal to noise ratio;

When there is no neighboring user equipment with a return function of 0, the adaptive weighting coefficient ω(u i ), the transmission rate r i (t) of each neighboring user equipment, and the product of the adaptive weighting coefficient and the transmission rate ω (u i ) are calculated. And r i (t), and selecting the user equipment with the largest product as the cooperative user equipment of the first user equipment, where
r i (t) = log 2 (1 + γ i (t)).
The device of claim 8, wherein the processing module is configured to configure the D2D communication resource for the first user equipment as the transmitting end and the third user equipment as the cooperative user equipment, including:

Sending the first D2D scheduling information to the first user equipment that is the transmitting end, where the first D2D scheduling information includes scheduling information that the first user equipment that is the transmitting end sends the data packet to the third user equipment that is the coordinated user equipment;

Transmitting second D2D scheduling information to the first user equipment as the transmitting end and the third user equipment as the cooperative user equipment, where the second D2D scheduling information includes the first user equipment as the transmitting end and the third user equipment as the cooperative user equipment The user equipment sends scheduling information of the data packet to the second user equipment that is the receiving end.
A virtual MIMO communication system based on D2D, comprising:

A base station and user equipment according to any one of claims 8 to 13;

Wherein, the first user equipment as the transmitting end is set to be the first as the collaborative user equipment. The third user equipment sends the data packet and the control information, where the control information is the scheduling information that the first user equipment that is the transmitting end sends the data packet to the third user equipment that is the coordinated user equipment; the first user equipment that serves as the sending end and the The third user equipment of the cooperative user equipment is configured to jointly send the data packet to the second user equipment as the receiving end by space-time coding according to the D2D communication resource configured by the base station.