CN114727317A - High-spectrum-efficiency communication system for realizing relay forwarding by using D2D communication equipment - Google Patents

High-spectrum-efficiency communication system for realizing relay forwarding by using D2D communication equipment Download PDF

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Publication number
CN114727317A
CN114727317A CN202210332427.6A CN202210332427A CN114727317A CN 114727317 A CN114727317 A CN 114727317A CN 202210332427 A CN202210332427 A CN 202210332427A CN 114727317 A CN114727317 A CN 114727317A
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communication
data
base station
power control
channel
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周林
李卫
毛志杰
何海光
苏岩
陈英梅
王卫卫
刘喆
陈华梁
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National University of Defense Technology
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    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W24/00—Supervisory, monitoring or testing arrangements
    • H04W24/02—Arrangements for optimising operational condition
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W28/00—Network traffic management; Network resource management
    • H04W28/16—Central resource management; Negotiation of resources or communication parameters, e.g. negotiating bandwidth or QoS [Quality of Service]
    • H04W28/18—Negotiating wireless communication parameters
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W52/00—Power management, e.g. TPC [Transmission Power Control], power saving or power classes
    • H04W52/02—Power saving arrangements
    • H04W52/0209—Power saving arrangements in terminal devices
    • H04W52/0212—Power saving arrangements in terminal devices managed by the network, e.g. network or access point is master and terminal is slave
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W52/00—Power management, e.g. TPC [Transmission Power Control], power saving or power classes
    • H04W52/04—TPC
    • H04W52/38—TPC being performed in particular situations
    • H04W52/46—TPC being performed in particular situations in multi hop networks, e.g. wireless relay networks
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02D—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN INFORMATION AND COMMUNICATION TECHNOLOGIES [ICT], I.E. INFORMATION AND COMMUNICATION TECHNOLOGIES AIMING AT THE REDUCTION OF THEIR OWN ENERGY USE
    • Y02D30/00—Reducing energy consumption in communication networks
    • Y02D30/70—Reducing energy consumption in communication networks in wireless communication networks

Abstract

The invention discloses a high-spectrum-efficiency communication system for realizing relay forwarding by using D2D communication equipment, which comprises a base station, a plurality of first communication equipment and second communication equipment, wherein the base station comprises a base station body and a plurality of first communication equipment; the first communication device supports D2D and CCFD; the base station responds to data requests or data issuing instructions of the two parties of the D2D to acquire channel parameters related to the two parties of the D2D; determining a power control parameter matched with the channel parameter according to the prior information; according to a first power control parameter in the power control parameters, data are sent to both sides of D2D by adopting a zero-forcing beamforming technology, and the data carry a second power control parameter; and D2D, when receiving the data from the base station, both sides adopt the non-orthogonal multiple access technology based on power domain multiplexing to forward the data to the connected second communication equipment according to the second power control parameter, wherein the second communication equipment is used for decoding the received data by adopting the serial interference cancellation technology. The invention can further relieve the problem of the scarce spectrum resources of the 6G network.

Description

High-spectrum-efficiency communication system for realizing relay forwarding by using D2D communication equipment
Technical Field
The invention belongs to the field of communication, and particularly relates to a high-spectrum-efficiency communication system for realizing relay forwarding by using D2D (Device to Device) communication equipment.
Background
5G communication technology has been put into commercial use worldwide, and 6G development has also been fully developed. In the future, massive device connections, various new services and application scenes which are continuously emerged can be expected to lead to explosive growth of mobile data traffic, and thus the spectrum efficiency is required to be greatly improved.
In the prior art, there are various techniques available for improving spectral efficiency, including interference suppression, increasing network density, and multi-antenna techniques, among others. However, compared with any previous generation communication system, the 6G communication system faces a usage scenario in which user data is highly intensive, which makes spectrum resources of the 6G network extremely scarce, and more schemes for alleviating the shortage of spectrum resources are required.
Disclosure of Invention
In order to solve the above problems in the prior art, the present invention provides a spectrum-efficient communication system using D2D communication devices to implement relay forwarding.
The technical problem to be solved by the invention is realized by the following technical scheme:
a high-spectrum-efficiency communication system for realizing relay forwarding by using D2D communication equipment comprises a base station, a plurality of first communication equipment and a plurality of second communication equipment; wherein the first communication device supports D2D communication and operates in a simultaneous co-frequency full duplex mode;
the base station is configured to: responding to data requests or data issuing instructions of both D2D communication parties, and acquiring channel parameters related to both D2D communication parties; determining a set of power control parameters matched with the channel parameters according to prior information; according to a first power control parameter related to a base station in the power control parameters, adopting a zero-forcing beamforming technology to send data to both communication parties of the D2D, wherein the data carries a second power control parameter related to relay forwarding in the power control parameters; the two communication parties of the D2D are the devices which carry out D2D communication with any two of the first communication devices;
the D2D two communication parties are used for: while receiving the data sent by the base station, according to the second power control parameter, adopting a non-orthogonal multiple access technology based on power domain multiplexing to forward the data from the base station to the respective connected second communication equipment;
both the D2D communication parties and the second communication devices connected to them decode the received data by using the serial interference cancellation technique.
Optionally, the first communication device is a device employing at least one active self-interference cancellation technique.
Optionally, the determining, by the base station, a set of power control parameters matched with the channel parameter according to a priori information includes:
inputting the channel parameters into a preset neural network model so that the neural network model outputs a group of power control parameters corresponding to the channel parameters;
the neural network model is obtained by training in advance based on a plurality of training samples, and each training sample comprises a sample channel parameter and a group of power control parameters corresponding to the sample channel parameter;
the training samples are obtained by solving a spectrum efficiency maximization problem for multiple times; the spectrum efficiency maximization problem is a convex optimization problem which takes a sample channel parameter as a known parameter, a power control parameter as a solving parameter and a function of calculating the subsystem spectrum efficiency as an objective function; the subsystem is a subsystem formed by second communication equipment connected with the base station, both the D2D communication parties and both the D2D communication parties.
Optionally, the determining, by the base station, a set of power control parameters matched with the channel parameters according to the prior information includes:
searching an experimental channel parameter with the highest similarity to the channel parameter from a plurality of preset experimental channel parameters;
determining a group of power control parameters corresponding to the searched experimental channel parameters according to the corresponding relation between the experimental channel parameters and the power control parameters obtained by the experiment in advance, and taking the group of power control parameters as a group of power control parameters matched with the channel parameters;
wherein the corresponding relation is obtained by solving a spectrum efficiency maximization problem for multiple times; the spectrum efficiency maximization problem is a convex optimization problem which takes experimental channel parameters as known parameters, power control parameters as solving parameters and a function for calculating the spectrum efficiency of a subsystem as an objective function; the subsystem is a subsystem formed by second communication equipment connected with the base station, both the D2D communication parties and both the D2D communication parties.
Optionally, the convex optimization problem is:
Figure BDA0003575523030000031
s.t.
Figure BDA0003575523030000032
Figure BDA0003575523030000033
fi(P)-(gi(P)+Rmin)＞0 i＝1,2,3,4；
|hd|2(PD1|h21|2+WN0)-|h22|2(P1|hb1u1|2+PD1|hLI|2+WN0)＞0；
|hd|2(PD2|h12|2+WN0)-|h11|2(P2|hb2u2|2+PD2|hLI|2+WN0)＞0；
wherein the content of the first and second substances,
Figure BDA0003575523030000034
Figure BDA0003575523030000035
Figure BDA0003575523030000041
SE represents the subsystem spectral efficiency; w represents the channel bandwidth; p represents the solving parameter; rminWhen i is 1,2 is equal to
Figure BDA0003575523030000042
Representing a lowest tolerated information transfer rate of the first communication device; rminWhen i is 3,4 is equal to
Figure BDA0003575523030000043
Representing a lowest tolerated information transfer rate of the second communication device; p1Represents a transmission power, P, at which the base station transmits data to one of the D2D communication parties2Indicating a transmission power at which the base station transmits data to the other of the D2D communication parties；PD1Representing the total transmission power, alpha, of said one device1And alpha2For a predetermined power division factor, alpha, of the one device1+α2＝1；PD2Representing the total transmission power, beta, of said other party's equipment1And beta2Is a preset power division factor, beta, of the other party's device1+β2＝1；
Figure BDA0003575523030000044
Represents the nominal transmission power of the base station,
Figure BDA0003575523030000045
representing a nominal transmit power of the first communication device; s.t. denotes the meaning to which it is bound; u. of1＝[u11,u12]TIndicating a precoding vector used when the base station transmits data to the one device; u. of2＝[u21,u22]TA precoding vector used when the base station transmits data to the other party device; h isb1Representing a channel parameter from said base station to said one device, hb2Represents a channel parameter from the base station to the other party device, [ h ]b1,hb2]T[u1,u2]I is an identity matrix, and superscript T represents matrix transposition; h isdRepresenting a channel parameter between the one device and the other device; h isLIRepresenting respective loop self-interference channel parameters of the one-party device and the other-party device; n is a radical of0A power spectral density representing additive white gaussian noise; h is11A channel parameter, h, representing the channel from said one device to a second communication device connected to the device12A channel parameter, h, representing a second communication device connected from said one device to said other device21A channel parameter, h, representing a second communication device connected from said other party's device to said one party's device22A channel parameter indicating a second communication device connected from the other party device to the one party device; k represents an iteration number mark when the convex optimization problem is solved by using an iterative algorithm;Pk 1，
Figure BDA0003575523030000051
p at the k-th iteration in turn1,P2,PD1,PD2The values substituted.
Optionally, the first communication device comprises a mobile terminal device supporting D2D communication and operating in a simultaneous co-frequency full duplex mode.
Alternatively, α1＞α2And beta is1＞β2。
Optionally, the forwarding is transcoding.
Optionally, the neural network model comprises: and (3) a Radial Basis Function (RBF) neural network model.
Optionally, the base station is a half-duplex base station, and the second communication device is a half-duplex mobile terminal device.
The invention has the beneficial effects that:
in the high-spectrum-efficiency communication system for realizing relay forwarding by using the D2D communication equipment, when a base station receives data requests of two parties of D2D communication, a group of power control parameters matched with channel parameters related to the two parties of D2D communication can be determined according to prior information; and then the base station sends the data to both D2D communication parties according to the first power control parameter in the group of parameters, and the both D2D communication parties are used as relays, so that the relays continuously forward the data to the second communication equipment connected with the relays according to the second power control parameter in the power control parameters determined by the base station. In the data transmission process, the base station uses a zero-forcing beamforming technology, that is, a Multi-User Multiple-Input Multiple-Output (MU-MIMO) architecture is actually used between the base station and the two D2D communication parties, so that the base station can simultaneously transmit data to the two D2D communication parties at the same frequency; because both communication parties of the D2D work in a Co-frequency Co-time Full Duplex (CCFD) mode, the communication parties can forward data to the second communication devices connected to the communication parties by using the same frequency resource while performing D2D communication; therefore, compared with the mode that the existing communication system uses a single half-duplex relay for data forwarding, the invention uses both the D2D communication parties of the CCFD as the relays to simultaneously perform data forwarding in the same frequency, so that the frequency spectrum efficiency of the subsystem formed by the base station, both the D2D communication parties and the second communication equipment connected with the same is improved in multiples; the communication system provided by the invention has higher spectral efficiency because the whole communication system can work according to the mode.
Moreover, the zero-forcing beamforming technology, the MU-MIMO technology, the Non-Orthogonal Multiple Access (NOMA) technology based on power domain multiplexing and the serial interference elimination technology used by the invention can solve the self-interference problem and the co-channel interference problem brought by the CCFD technology, so that two communication parties of the D2D can simultaneously work at the same frequency without influencing the communication quality of the communication parties and the second communication equipment.
The present invention will be described in further detail with reference to the accompanying drawings and examples.
Drawings
Fig. 1 is a schematic structural diagram of a high spectrum-efficient communication system for implementing relay forwarding by using a D2D communication device according to an embodiment of the present invention;
fig. 2 is a schematic diagram of various interference signals faced by a first communication device during data transmission in the embodiment of the present invention;
fig. 3 is a schematic diagram of interference signals faced by a second communication device when receiving data in the embodiment of the present invention;
fig. 4 is a schematic network structure diagram of a neural network model used in the embodiment of the present invention.
Detailed Description
The present invention will be described in further detail with reference to specific examples, but the embodiments of the present invention are not limited thereto.
In order to further alleviate the problem of the scarce spectrum resources of the 6G network, the embodiment of the invention provides a high-spectrum-efficiency communication system for realizing relay forwarding by using D2D communication equipment; referring to fig. 1, the system includes: a base station 10, a number of first communication devices 20 and a number of second communication devices 30.
The base station 10 may be a full-duplex or half-duplex operating base station, among others. The first communication device 20 supports D2D communication and operates in a simultaneous co-frequency full duplex mode; for example, the first communication device 20 may be a relay device supporting D2D communication and operating in a simultaneous co-frequency full duplex mode, or the first communication device 20 may also be a mobile terminal device, a non-mobile terminal device, or the like supporting D2D communication and operating in a simultaneous co-frequency full duplex mode. The second communication device 30 may be a mobile terminal device, or may be a non-mobile terminal device, a relay device, or another base station; the second communication device 30 may operate in a half-duplex mode or in a full-duplex mode.
The base station 10 is configured to: responding to data requests or data issuing instructions of both D2D communication parties, and acquiring channel parameters related to both D2D communication parties; determining a set of power control parameters matched with the channel parameters according to the prior information; and according to a first power control parameter related to the base station in the power control parameters, sending data to both communication parties of the D2D by adopting a zero-forcing beamforming technology, wherein the data carries a second power control parameter related to relay forwarding and contained in the power control parameters.
Referring to fig. 1, the two parties of D2D communication are devices that are performing D2D communication with any two of the first communication devices 20 included in the communication system. To facilitate the distinction between the two D2D communication parties, one of the devices is labeled D1The other party's device is marked as D2。
In practical application, if both communication parties of D2D are terminal devices, the data request initiated by the D2D bidirectional communication base station may be initiated by the user of the terminal device actively; if both D2D communication parties are relay devices, the data request initiated by both D2D communication parties to the base station may be initiated by both D2D communication parties to the base station in response to the data request of the respectively connected second communication device 30. In addition, the base station can also independently issue data, specifically, the base station responds to a data issuing command configured for the base station to autonomously issue data; for example, a base station administrator issues a disaster warning notification through the base station.
In the embodiment of the present invention, the content of the data transmitted in the communication system is not limited, and may be voice data, image data, control data, and the like.
It is understood that the channel parameters related to the two D2D communication parties may include channel parameters from the base station 10 to each of the two D2D communication parties, channel parameters that are reciprocal between the two D2D communication parties, loop self-interference channel parameters of each of the two D2D communication parties, and channel parameters from each of the two D2D communication parties to the second communication device 30.
In practical applications, the base station 10 obtains channel parameters related to both D2D communication parties by: the base station 10 performs downlink channel estimation to obtain channel parameters of each of two communication parties from the base station 10 to D2D; the first communication device 20 of each of the two communication parties D2D performs downlink channel estimation, so as to obtain downlink channel information between the first communication device and the second communication device 30; the channel information between the two D2D communication parties may also be obtained by performing channel estimation by each party; furthermore, since both D2D communications are CCFD-enabled, the slave D is1To D2And a channel parameter of, and from D2To D1May be reciprocal. The loop self-interference channel parameters may be measured in advance at the first communication device 20 side to obtain a statistical average value, and recorded in the base station.
It is understood that the above-mentioned a priori information is information obtained in advance through a large number of experiments. By carrying out a large number of experiments in advance, the corresponding relation or other incidence relations between the channel parameters and the power control parameters can be established, so that the matched power control parameters can be directly determined based on the prior information in practical application. For clarity of the description, a specific implementation manner of determining, by the base station, the power control parameter matching the channel parameter according to the prior information is illustrated subsequently.
D2D both parties in communication, for: while receiving the data transmitted from the base station 10, according to the second power control parameter of the power control parameters, the non-orthogonal multiple access technology based on power domain multiplexing is adopted to forward the number from the base station 10 to the respectively connected second communication equipment 30Accordingly. Accordingly, both D2D communication parties and the second communication device 30 connected to them use the serial interference cancellation technique to decode the received data. To facilitate distinguishing the second communication devices 30 to which the two D2D communication parties are respectively connected, D is used1The second communication device 30 of the connection is marked C1D is2The second communication device 30 of the connection is marked C2。
It will be appreciated that both parties to D2D communication are used as relays here. The manner in which both D2D communication parties perform forwarding as a relay may include: Amplify-and-Forward (AF), Decode-and-Forward (DF), Selective Relay (SR), Compress-and-Forward (CF), or Incremental Relay (IR), among others.
As shown in FIG. 1, the base station 10 transmits data x to both D2D communication parties using zero-forcing beamforming1And data x2The hybrid transmit signal. Wherein, the data x1Is sent to D1Of (2) data x2Is sent to D2In (1). Since the transmission signal is generated by the base station 10 by using the null-breaking beamforming technology, it is equivalent to the direction D of the base station 101Has transmitted data x1To D2Has transmitted data x2。D1After receiving the signal from the base station, it decodes it to obtain data x3Data x3Forward to C1While D is1May also be directed to D2Transmitting data x12。D2After receiving the signal from the base station, it decodes it to obtain data x4Data x4Forward to C2While D is2May also be directed to D1Transmitting data x21。
Due to the CCFD mode of operation, the first communication device 20 will face loop self-interference problems; the loop self-interference here means that after the first communication device 20 transmits a signal outwards using a certain frequency at a certain time, the transmitted signal can be received by the receiving antenna of the first communication device 20 itself at the same time. Therefore, the hardware transceiving channels of the device with CCFD function are designed with a certain isolation, so that the signal power emitted from the transmitting antenna to the space is suppressed and reduced when reaching the receiving antenna, thereby solving the problem of loop self-interference; this approach solves the self-interference problem from the hardware design and is called passive self-interference cancellation technique.
If the design effect of the hardware isolation is not good, an active self-interference elimination technology can be further adopted. The active interference cancellation technology is to construct a cancellation signal or an estimation signal at a receiving end, and then add or subtract the self-interference signal, so as to achieve the purpose of effectively suppressing the self-interference signal. Active interference cancellation can be further divided into self-interference cancellation in the analog domain and self-interference cancellation in the digital domain. The self-interference elimination technology in the analog domain is to eliminate a self-interference signal in a radio frequency or baseband domain; the self-interference elimination technology in the digital domain is to realize self-interference elimination in the digital domain by means of an accurate self-interference channel estimation technology.
The passive self-interference cancellation technique is possessed by the device which CCFD works; the active self-interference cancellation technique may be selectively used or not used, or one or more selected according to the suppression requirement of the self-interference signal.
In the high-spectrum-efficiency communication system for realizing relay forwarding by using the D2D communication equipment, when the base station receives data requests of both D2D communication parties, a group of power control parameters matched with channel parameters related to both D2D communication parties can be determined according to prior information; and then the base station sends the data to both D2D communication parties according to the first power control parameter in the group of parameters, and the both D2D communication parties are used as relays, so that the relays continuously forward the data to the second communication equipment connected with the relays according to the second power control parameter in the power control parameters determined by the base station. In the data transmission process, the base station uses the zero-forcing beam forming technology, namely the base station and the two communication parties of the D2D are actually multi-user-multi-input-multi-output, so the base station can simultaneously transmit data to the two communication parties of the D2D at the same frequency; because both D2D communication devices are working in CCFD mode, they can use the same frequency resource to forward data to their respective connected second communication devices while performing D2D communication; therefore, compared with the mode that the existing communication system uses a single half-duplex relay for data forwarding, the invention uses both D2D communication parties of the CCFD as the relays to simultaneously perform data forwarding in the same frequency, so that the spectrum efficiency of a subsystem consisting of the base station, both D2D communication parties and the connected second communication equipment is improved by times; compared with the traditional TDD and FDD, the CCFD has different partitioning mechanisms on time domain resources and frequency domain resources, and also benefits from the D2D communication technology, so that the relay can simultaneously receive and transmit data on the same frequency domain resource, and can simultaneously share the same frequency spectrum resource with the relay of the counterpart in D2D communication. Because the whole communication system can work according to the data transmission mode, the communication system provided by the embodiment of the invention has higher frequency spectrum efficiency.
In addition, the zero-forcing beamforming technology, the MU-MIMO technology, the NOMA technology based on power domain multiplexing and the serial interference elimination technology used by the invention can solve the self-interference problem and the co-channel interference problem brought by the CCFD technology, so that two D2D communication parties can simultaneously work at the same frequency without influencing the communication quality of the D2D communication parties and the communication quality of second communication equipment.
Specifically, referring to the solid arrows in fig. 2, D is shown on the same spectrum resource at the same time without considering interference1、D2Base station, C1And C2The transmission of useful data between includes:
(a) the base station adopts the zero forcing beam forming technology to D1And D2Transmitting mixed data x1And data x2Is equivalent to the base station towards D1Transmitting data x1In the direction of D2Transmitting data x2。
(b)D1Receiving data x from base station1Reception D2Transmitted data x21To D2Transmitting data x12And is parallel to C1Transmitting data x3(ii) a The data x3Is D1For data x1Decoding the data to obtain the data;
(c)D2receiving data x from base station2Reception D1Sent data x12To D1Transmitting data x21And sends data x to C24(ii) a The data x4Is D2For data x2Decoding the data to obtain the data;
(d)C1receiving D1Transmitted data x3While C is2Receiving D2Transmitted data x4。
Wherein for D1And D2In addition to receiving data sent by each party to the receiver, the receiver is also subjected to various interferences. See dashed arrow in FIG. 2, indicated as D1For example, D1In addition to receiving data x useful to itself1And data x21In addition, the data x sent by the base station is received2、D1Self-issued data x3And data x12And D2Sent out data x4The interference of (2). Wherein, the data x3And data x12For D1Self-interference, data x2And data x4For D1It is said to be co-channel interference.
A second communication device to which either of the two D2D communication partners is connected may also experience various types of interference in addition to receiving the forwarded data. See dashed arrow in FIG. 3, denoted by C1For example, C1In addition to receiving data x useful to itself3In addition to this, also from D1Sent out data x12、D2Sent out data x21And data x4The interference of (2). Since the second communication device needs to relay the forwarding to acquire data from the base station, that is, the second communication device is usually far from the base station, the data x sent by the base station1And data x2To C1It can be ignored.
In order to solve the various interference problems shown above, the embodiments of the present invention employ various means. First, since the base station and the D2D both communicate with each other in the embodiment of the present invention, they are MU-MIMO, so a zero-forcing beamforming technique can be adopted at the base station side, the base station equates multiple transmitting antennas of the base station to 2 transmitting antennas, so that channel vectors of two communication parties of D2D are orthogonal, and the base station sends the signals to D2Data x of2For D1Without influence, i.e. equivalent to D1Receiving only data x sent by base station to itself1(ii) a In the same way, the base station sends D1Data x of (2)1For D2Without influence, i.e. equivalent to D2Receiving only data x sent by base station to itself2. Thus, the problem of co-channel interference at the level from the base station to the relay is solved.
In addition, in the embodiment of the present invention, at least one self-interference cancellation technique is adopted on the first communication device 20 side to cancel the self-interference problem. For example, in FIG. 2, D1After the self-interference elimination technique is adopted, D1Received from the space by the receiving antenna from the data x3And data x12The interference of (2) can be effectively reduced.
In addition, the first communication device 20 side in the embodiment of the present invention further adopts a NOMA technique based on power domain multiplexing, and allocates the power of transmitting data to the second communication device 30 and the power of transmitting data to another second communication device 20 communicating with D2D in different sizes; thus, the second communication device 30 and the other first communication device 30, which are the data receiving sides, can separate the useful data and the interference data from the received data by using the serial interference cancellation technology.
For example, using NOMA technique based on power domain multiplexing, D in FIG. 22To D1Data x of21And to C2Data x of4Are different in power level; thus, D in FIG. 21Receiving useful data x at the same time and same frequency1Interference data x2Interference data x12Useful data x21Interference data x4And interference data x3Thereafter, the data x is disturbed2The zero-forcing beamforming technique is solved, the interference data x12And interference data x3Is solved by self-interference elimination technology and remainsThe following is the useful data x1Useful data x21And interference data x4(ii) a Due to D1And D2Are in close range D2D, so data x1Is less than data x21And data x4And data x21And data x4And because the NOMA technology based on power domain multiplexing is limited in size, the data x1Data x21And data x4Is determined, whereby D1The three data can be separated by selecting an adaptive decoding sequence according to the size sequence of the three data; that is, D1Is subjected to a pressure from D2Sent out data x4The co-channel interference problem of (2) can also be solved.
For another example, using NOMA technique based on power domain multiplexing, D in FIG. 32To D1Data x of21And to C2Data x of4Are different in power level; in the same way, D1To D2Data x of12And to C1Data x of3Are also different. Thus, C2、C2All the data with large power can be translated first, and then the data with small power can be translated.
In practical applications, if the first communication device is a terminal device, when data transfer is performed while the first communication device performs D2D communication, it is preferable to set the power to the D2D communication partner to be larger than the power to the second communication device. Referring to fig. 2 and 3, if the first communication device is a terminal device, x is preferable in power size21＞x4And x is12＞x3. Of course, this preferred power allocation may be used if the first communication device is a relay device or other type of device, or vice versa.
In summary, the self-interference problem and the co-channel interference problem caused by the CCFD technique are solved by the implementation of the present invention, so that in the implementation of the present invention, both D2D communication parties can simultaneously work at the same frequency without affecting the communication quality of the two parties and the connected second communication device, that is, two relays can simultaneously occupy the same spectrum resource to perform data forwarding, thereby further improving the utilization rate of the spectrum resource, that is, improving the spectrum efficiency.
In the following, a specific implementation manner of determining, by the base station, a set of power control parameters matched with the channel parameters according to the prior information is illustrated.
For example, in one implementation, the determining, by the base station according to the a priori information, a set of power control parameters matching the channel parameters may include:
inputting the channel parameters into a preset neural network model so that the neural network model outputs a group of power control parameters corresponding to the channel parameters.
The neural network model is obtained by training in advance based on a plurality of training samples, and each training sample comprises a sample channel parameter and a group of power control parameters corresponding to the sample channel parameter. Moreover, a plurality of training samples adopted during training are obtained by solving a spectrum efficiency maximization problem for a plurality of times; the spectrum efficiency maximization problem is a convex optimization problem which takes a sample channel parameter as a known parameter, a power control parameter as a solving parameter and a function of calculating the subsystem spectrum efficiency as an objective function; the subsystem is a subsystem formed by the base station, the second communication devices connected with both the D2D communication party and the D2D communication party.
The neural network model may be an RBF (radial basis function) neural network model. Or, the neural network model can also be built by utilizing a residual error network; FIG. 4 is a diagram schematically illustrating the structure of a neural network model built by using a residual network; the Reshape layer is a network structure for performing format conversion on data output by the full connection layer.
It can be understood that the power control parameter corresponding to the sample channel parameter is identification information of the sample channel parameter, and belongs to the prior information. That is, the neural network model is obtained based on prior information training. In practical application, massive sample channel parameters can be obtained, the sample channel parameters are respectively substituted into the spectrum efficiency maximization problem to be solved, an optimal solution corresponding to one sample channel parameter can be obtained in each solving, and the optimal solution is a power control parameter corresponding to the sample channel parameter. By constructing massive training samples in this way, a neural network model capable of predicting optimal power control parameters according to sample channel parameters can be trained based on the massive samples.
In another implementation, the determining, by the base station according to the prior information, a set of power control parameters matching the channel parameters may include:
(1) and searching for an experimental channel parameter with the highest similarity to the channel parameter from a plurality of preset experimental channel parameters.
Specifically, the channel parameters of a single channel are usually channel vectors or channel matrices, and the channel parameters obtained by the base station in the embodiment of the present invention include parameters of multiple channels, and thus include multiple channel vectors/matrices; therefore, in step (1), the similarity may be obtained by obtaining the similarity of the channel vectors/matrices of the same channel; then, a weighted average of several similarities is obtained, and the experimental channel parameter with the highest value is used as the search result.
As an example, referring to fig. 2 and fig. 3, the channel parameters obtained by the base station include: d1And D2Channel parameter h betweend，D1And D2Respective loop self-interference channel parameter hLIFrom the base station to D1Of the channel parameter hb1From the base station to D2Of the channel parameter hb2，D1To C1Of the channel parameter h11，D2To C2Of the channel parameter h22，D1To C2Of the channel parameter h12And D2To C1Of the channel parameter h21. Each group of experimental channel parameters comprises parameters of the same channel corresponding to the channel parameters, and h is used for each experimental channel parameterd′、hLI′、hb1'、hb2'、h11'、h22'、h12' and h21' to represent; thus, the way to find an experimental channel parameter with the highest similarity to the channel parameters can be represented by the following formula:
Figure BDA0003575523030000121
wherein, eta represents the calculated similarity, c (-) represents the function of solving the matrix/vector similarity, such as the function of solving cosine similarity, Euclidean distance, etc.; lambda [ alpha ]1～λ8Are all weighting factors.
(2) And determining a group of power control parameters corresponding to the searched experimental channel parameters according to the corresponding relation between the experimental channel parameters and the power control parameters obtained by the experiment in advance, wherein the group of power control parameters is used as a group of power control parameters matched with the channel parameters.
Wherein, the corresponding relation can be obtained by solving a spectrum efficiency maximization problem for multiple times; the spectrum efficiency maximization problem is a convex optimization problem which takes experimental channel parameters as known parameters, power control parameters as solving parameters and a function for calculating the spectrum efficiency of a subsystem as an objective function.
It can be understood that the above correspondence is a priori information used by the base station. In practical application, a large amount of experimental channel parameters can be obtained, and the experimental channel parameters are respectively substituted into the spectrum efficiency maximization problem to be solved, so that an optimal solution corresponding to the experimental channel parameters can be obtained every time the optimal solution is solved, and the optimal solution is the power control parameters corresponding to the experimental channel parameters. The corresponding relation is solidified in the base station, so that the base station can be subsequently searched and used in practice.
The following is a detailed description of the construction and solution process of the above-mentioned spectrum efficiency maximization problem.
The transmission signal X of the base station can be represented by the symbols of the data items shown in FIGS. 2 and 3BSExpressed as:
Figure BDA0003575523030000131
wherein u is1＝[u11,u12]T,u2＝[u21,u22]TEach being data x1,x2The precoding vector is used when the base station adopts a precoding technology to preprocess the transmitted signal. Here, the precoding technique is a common technical means for preprocessing a transmission signal by a base station in a MIMO system, and aims to effectively suppress multi-user interference in a MIMO channel. In the embodiment of the invention, the channel vectors of the two communication parties of D2D are orthogonal due to the use of the precoding vector, so that D is enabled1Receiving only data x1，D2Receiving only data x2. The zero-forcing beamforming technique is a precoding technique.
D1To C1Data x of (2)3Has a power of alpha1PD1，D1To D2Data x of12Has a power of alpha2PD1，α1,α2Is D1Is preset power division factor, alpha1+α21. In addition, suppose D1And D2All of them are terminal devices, and since the terminal device firstly receives data transmitted from the D2D communication object and secondly relays data belonging to the second communication device as a relay, α is set here1＜α2. In the same way, D2At a power of beta1PD2To C2Transmitting data x4And with a power beta2PD2To D1Transmitting data x21，β1,β2Is D2Is preset power division factor, beta1+β21, and assume β1＜β2。
Thus, D1Of the transmission signal XD1And D2Of the transmission signal XD2Respectively as follows:
Figure BDA0003575523030000132
see fig. 2 for a data transmission and interference model, D1Of the received signal yD1As follows:
Figure BDA0003575523030000141
wherein h isb1Representing one device D of two communicating parties from a base station to D2D1Of the channel parameter, hb2Representing the other device D of both parties communicating from the base station to D2D2Of [ h ] is transmitted to the channelb1,hb2]T[u1,u2]I is an identity matrix. h isdRepresents D1And D2Inter-channel parameters; h isLIIs shown by D1、D2Respective loop self-interference channel parameters; n is a radical of0-174dBm/Hz, which is the power spectral density of additive white gaussian noise; w denotes a channel bandwidth.
Since the base station uses the zero-forcing beamforming technique, the summation term in equation (3)
Figure BDA0003575523030000142
Therefore, the formula (3) can be simplified as follows:
Figure BDA0003575523030000143
for the same reason, D2Of the received signal yD2As follows:
Figure BDA0003575523030000144
for D1In other words, serial interference cancellation is used to decode the received signal in layers, with the decoding order being x21→x4→x1. Thus, D1For data x21The snr obtained by decoding is:
Figure BDA0003575523030000145
D1for data x21After decoding, the data x can be decoded21Separating from the received signal; thereby enabling data x to be subsequently decoded when other data is decoded21The interference is not unknown any more, thereby improving the signal-to-interference-and-noise ratio when other data are decoded subsequently.
Then, D1Continue to data x4Proceed decoding, at this time D1For data x4The snr obtained by decoding is:
Figure BDA0003575523030000151
it can be seen that the interference term in the denominator in equation (7) does not take the data x into account21Corresponding interference term beta2PD2|hd|2。
D1For data x4After decoding, the data x can be further decoded4Separated from the remaining received signal, followed by1For data x1When decoding, data x4Interference terms that are no longer unknown; thus, D1For data x1The signal-to-interference-and-noise ratio when decoding is performed is as follows:
Figure BDA0003575523030000152
it can be seen that the interference term in the denominator in equation (8) does not have data x at this time4Corresponding interference term beta1PD2|hd|2Nor data x21Corresponding interference term beta2PD2|hd|2。
For the same reason, for D2In particular, serial interference cancellation techniques are used to hierarchically decode and decode the received signalThe code order is x12→x3→x2；D2The signal-to-interference-and-noise ratios obtained by decoding the three data are sequentially as follows:
Figure BDA0003575523030000153
Figure BDA0003575523030000154
Figure BDA0003575523030000155
on the side of the second communication device, C1Will receive D1Forwarded signal XD1. At the same time, C1May also receive D2Forwarding C2Signal X ofD2. In the same way, C2Will receive D2Forwarded signal XD2. At the same time, C2May also receive D1Forward to C1Signal X ofD1(ii) a Thus, C1And C2The received signals of (a) are respectively as follows:
Figure BDA0003575523030000156
Figure BDA0003575523030000161
let h1＝[h11,h12]Wherein h is11,h12Respectively represent D1To C1、C2The channel parameters of (a); let h2＝[h21,h22]Wherein h is21,h22Respectively represent D2To C1、C2The channel parameters of (1).
Since a is assumed in advance1＜α2Therefore C is1Is x12→x3Corresponding to, C1The signal-to-interference-and-noise ratios obtained by decoding the two data are sequentially as follows:
Figure BDA0003575523030000162
Figure BDA0003575523030000163
since beta is assumed in advance1＜β2Therefore, C is2Is x21→x4Corresponding to, C2The signal-to-interference-and-noise ratios obtained by decoding the two data are sequentially as follows:
Figure BDA0003575523030000164
Figure BDA0003575523030000165
wherein, the use premise of NOMA technology based on power multiplexing requires gammaD1_x4＞γC2_x4And requires γD2_x3＞γC1_x3. Here, γ is requiredD2_x3＞γC1_x3Is to ensure C1Capable of successive decoding, i.e. for ensuring C1For data x12Can continue to decode the data x3And decoding is carried out. For the same reason, require γD1_x4＞γC2_x4To ensure C2For data x21Can continue to decode the data x4And decoding is carried out.
According to the Shannon theorem, the method comprises the following steps: information transmission rate of R-W log2(1+ γ), γ representing a generalized signal to interference plus noise ratio; therefore, the information transmission rate corresponding to each signal to interference and noise ratio can be calculated from the above equations (6) to (11) and equations (14) to (17).
Assuming that both D2D communication parties forward data in a decoding forwarding manner, it can be determined that:
RD1＝RD1_x21 (18)；
RD2＝RD2_x12 (19)；
RC1＝min{RD1_x1,RC1_x3} (20)；
RC2＝min{RD2_x2,RC2_x4} (21)。
wherein R isD1Represents D1The information transmission rate of (2); rD2Represents D2Information transmission rate of RC1Indicating a second communication device C1Information transmission rate of (2), RC2Indicating a second communication device C2The information transmission rate of (2). RD1_x21Represents D1To D2Useful data x sent from21Information transmission rate, R, obtained by decodingD2_x12Represents D2To D1Useful data x sent from12Information transmission rate, R, obtained by decodingD1_x1Is shown by D1Useful data x sent to base station1Information transmission rate, R, obtained by decodingC1_x3Is represented by C1To D1Useful data x sent from3Information transmission rate, R, obtained by decodingD2_x2Represents D2Useful data x from base station2Information transmission rate, R, obtained by decodingC2_x4Is represented by C2To D2Useful data x sent from4The information transmission rate obtained by decoding.
The total information transmission rate of a system formed by the base station, the relay and the second communication device is known as follows:
R＝RD1+RD2+RC1+RC2 (22)。
to this end, according to the mathematical model of the total information transmission rate R, with the goal of maximizing the spectral efficiency, an initial problem of maximizing the spectral efficiency is constructed as follows:
Figure BDA0003575523030000181
wherein SE represents spectral efficiency; w represents the channel bandwidth; s.t. denotes the meaning to which it is bound;
Figure BDA0003575523030000182
which represents the nominal transmit power of the base station,
Figure BDA0003575523030000183
which represents the nominal transmit power of the relay,
Figure BDA0003575523030000184
indicating the lowest tolerated information transfer rate for the relay,
Figure BDA0003575523030000185
representing a lowest tolerated information transfer rate of the second communication device; rD1_x4Represents D1For data x4The information transmission rate obtained by decoding; rD2_x3Represents D2For data x3The information transmission rate obtained by decoding; rC1_x3Is represented by C1To D1Useful data x sent from3Information transmission rate, R, obtained by decodingC2_x4Is represented by C2To D2Useful data x sent from4The information transmission rate obtained by decoding.
In the above problem, the constraint condition (a) is a constraint on the transmission power of two equivalent transmission antennas of the base station; constraint (b) is a constraint on the transmit power of both D2D communication parties; the constraint condition (c) is a constraint to ensure the quality of service of the first communication device; the constraint (d) is a constraint that ensures the quality of service of the second communication device; if the first communication device and the second communication device are both terminal devices, the constraints (c) and (d) are the minimum requirements for ensuring the quality of service for the user. The constraint (e) is to ensure C2Constraint capable of successive decoding, constraint (f) being to ensure C1Constraints that can be decoded consecutively.
Then, the problem is solved, and the mathematical model of the problem is analyzed to find that neither the objective function nor part of the constraint conditions of the problem are convex or concave, that is, the mathematical model of the problem is a non-convex optimization model, and a convex optimization method cannot be adopted to obtain the maximum value. Thus, it can be converted into a convex optimization model by mathematical theoretical analysis and derivation. The specific transformation process is as follows:
the components in the objective function are first expanded into a form of subtraction of the two functions, as follows:
Figure BDA0003575523030000191
Figure BDA0003575523030000192
Figure BDA0003575523030000193
Figure BDA0003575523030000201
by making a pair of fi(P),gi(P) 1,2,3,4, find Hessian matrix (translated as a blackplug matrix, Hessian matrix, Hatheri matrix, or Hatheri matrix), fi(P) and gi(P) are all concave functions derived from
Figure BDA0003575523030000202
And
Figure BDA0003575523030000203
also a concave function. The objective function R can thus be equivalently in the form of concave minus concave, i.e., R ═ f (p) -g (p).
Then, the constraints of the problem are analyzed: the constraints (a) and (b) of equation (23) are linear constraints; to pairIn terms of the constraints (c) and (d), the reason is that
Figure BDA0003575523030000204
And
Figure BDA0003575523030000205
is a constant, and subtracting a constant from a function of the concave-concave subtraction does not affect the concave-convex property itself, so the constraints (c) and (d) of equation (23) can be in the form of concave-concave subtraction, as follows:
fi(P)-(gi(P)+Rmin)＞0 i＝1,2,3,4 (28)。
wherein R isminWhen i takes 1,2 is
Figure BDA0003575523030000206
RminWhen i takes 3,4 is
Figure BDA0003575523030000207
The constraints (e) and (f) of equation (23) are simplified to obtain:
|hd|2(PD1|h21|2+WN0)-|h22|2(P1|hb1u1|2+PD1|hLI|2+WN0)＞0 (29)；
|hd|2(PD2|h12|2+WN0)-|h11|2(P2|hb2u2|2+PD2|hLI|2+WN0)＞0 (30)。
it can be seen that the simplified constraints (e) and (f) are linear constraints.
So far, it can be seen by analyzing and deriving the objective function and the constraint condition that the problem is a typical DC planning problem, and thus the spectrum optimization problem can be simply expressed as:
Figure BDA0003575523030000211
in order to solve the DC planning problem, a CCP (conditional-conditional procedure) algorithm may be adopted to convert the DC planning problem into a convex optimization problem, and then an optimal solution of the spectral efficiency is obtained through an iterative algorithm.
In particular, if gi(P) is approximated by a first order Taylor expansion, then fi(P)-gi(P) can be approximated as:
Figure BDA0003575523030000212
wherein, P0Expressed as a function gi(P) an initial value set for argument P.
Therefore, the first-order taylor expansion approximation is performed on each of equations (24) to (27) in accordance with the expansion method shown in equation (32):
Figure BDA0003575523030000213
Figure BDA0003575523030000221
Figure BDA0003575523030000222
Figure BDA0003575523030000223
wherein P in the formulae (33) to (36)1 0,
Figure BDA0003575523030000224
P for the k-th iteration 01,P2,PD1,PD2Setting an initial value; k is an indication of the number of iterations followed byIncrease in the number of iterations, P in equations (33) to (36)1 0,
Figure BDA0003575523030000231
Will be respectively replaced by P at the k-th iteration1,P2,PD1,PD2A specific value of (i), i.e. P1 k,
Figure BDA0003575523030000232
Thus, with P1 k,
Figure BDA0003575523030000233
Successively replacing P in the formulae (33) to (36)1 0,
Figure BDA0003575523030000234
And the four new generations obtained are shown in formula (31), the obtained problem is expressed as:
Figure BDA0003575523030000235
s.t.
Figure BDA0003575523030000236
Figure BDA0003575523030000237
fi(P)-(gi(P)+Rmin)>0i＝1,2,3,4；
|hd|2(PD1|h21|2+WN0)-|h22|2(P1|hb1u1|2+PD1|hLI|2+WN0)＞0；
|hd|2(PD2|h12|2+WN0)-|h11|2(P2|hb2u2|2+PD2|hLI|2+WN0)＞0；
wherein the content of the first and second substances,
Figure BDA0003575523030000238
Figure BDA0003575523030000241
Figure BDA0003575523030000242
it can be seen that, at this time, the objective function and the constraint condition of the problem are both converted into concave function and concave constraint, and belong to a typical convex optimization problem, so that an iterative algorithm can be used for solving to obtain an optimal solution P when the spectral efficiency is maximum*For a specific iterative solution process, reference may be made to a manner of solving a problem by using an iterative algorithm in the prior art, and details are not repeated in the embodiments of the present invention.
The above is a detailed process for constructing and solving the spectrum efficiency maximization problem.
In summary, the high spectrum efficiency communication system that uses D2D communication devices to realize relay forwarding according to the embodiments of the present invention has higher spectrum efficiency, and the CCFD and D2D communication technologies are used to enable the data transmission rate in the system to be higher, so that the present invention can adapt to the development trend of future mobile communication system with dense user data, high spectrum efficiency and low energy consumption.
It should be noted that the terms "first" and "second" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the present invention, "a plurality" means two or more unless specifically defined otherwise.
In the description herein, references to the description of the term "one embodiment," "some embodiments," "an example," "a specific example," or "some examples," etc., mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the terms used above are not necessarily intended to refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. Furthermore, various embodiments or examples described in this specification can be combined and combined by those skilled in the art.
While the present application has been described in connection with various embodiments, other variations to the disclosed embodiments can be understood and effected by those skilled in the art in practicing the claimed application, from a review of the drawings, the disclosure, and the appended claims. In the specification, the word "comprising" does not exclude other elements or steps, and the word "a" or "an" does not exclude a plurality. Some measures are described in mutually different embodiments, but this does not indicate that these measures cannot be combined to give good results.
The foregoing is a more detailed description of the invention in connection with specific preferred embodiments and it is not intended that the invention be limited to these specific details. For those skilled in the art to which the invention pertains, several simple deductions or substitutions can be made without departing from the spirit of the invention, and all shall be considered as belonging to the protection scope of the invention.

Claims (10)

1. A high-spectrum-efficiency communication system for realizing relay forwarding by using D2D communication equipment is characterized by comprising a base station, a plurality of first communication equipment and a plurality of second communication equipment; wherein the first communication device supports D2D communication and operates in a simultaneous co-frequency full duplex mode;
the base station is configured to: responding to data requests or data issuing instructions of both D2D communication parties, and acquiring channel parameters related to both D2D communication parties; determining a set of power control parameters matched with the channel parameters according to prior information; according to a first power control parameter related to a base station in the power control parameters, data is sent to the two communication parties of the D2D by adopting a zero-forcing beamforming technology, and the data carries a second power control parameter related to relay forwarding in the power control parameters; the two D2D communication parties are devices which carry out D2D communication with any two of the first communication devices;
the D2D two communication parties are configured to: while receiving the data sent by the base station, according to the second power control parameter, adopting a non-orthogonal multiple access technology based on power domain multiplexing to forward the data from the base station to the respective connected second communication equipment;
both the D2D communication parties and the second communication devices connected to them decode the received data by using the serial interference cancellation technique.
2. The system of claim 1, wherein the first communication device is a device that employs at least one active self-interference cancellation technique.
3. The system of claim 1, wherein the base station determines a set of power control parameters matching the channel parameters according to a priori information, and the determining comprises:
inputting the channel parameters into a preset neural network model so that the neural network model outputs a group of power control parameters corresponding to the channel parameters;
the neural network model is obtained by training in advance based on a plurality of training samples, and each training sample comprises a sample channel parameter and a group of power control parameters corresponding to the sample channel parameter;
the training samples are obtained by solving a spectrum efficiency maximization problem for multiple times; the spectrum efficiency maximization problem is a convex optimization problem which takes a sample channel parameter as a known parameter, a power control parameter as a solving parameter and a function of calculating the subsystem spectrum efficiency as an objective function; the subsystem is a subsystem formed by second communication equipment connected with the base station, both the D2D communication parties and both the D2D communication parties.
4. The system of claim 1, wherein the base station determines a set of power control parameters matching the channel parameters according to a priori information, and comprises:
searching an experimental channel parameter with the highest similarity to the channel parameter from a plurality of preset experimental channel parameters;
determining a group of power control parameters corresponding to the searched experimental channel parameters according to the corresponding relation between the experimental channel parameters and the power control parameters obtained by the experiment in advance, and taking the group of power control parameters as a group of power control parameters matched with the channel parameters;
wherein the corresponding relation is obtained by solving a spectrum efficiency maximization problem for multiple times; the spectrum efficiency maximization problem is a convex optimization problem which takes experimental channel parameters as known parameters, power control parameters as solving parameters and a function for calculating the spectrum efficiency of a subsystem as an objective function; the subsystem is a subsystem formed by second communication equipment connected with the base station, both the D2D communication parties and both the D2D communication parties.
5. The system according to claim 3 or 4, wherein the convex optimization problem is:
Figure FDA0003575523020000021
s.t.
Figure FDA0003575523020000022
Figure FDA0003575523020000023
fi(P)-(gi(P)+Rmin)>0i＝1,2,3,4；
|hd|2(PD1|h21|2+WN0)-|h22|2(P1|hb1u1|2+PD1|hLI|2+WN0)＞0；
|hd|2(PD2|h12|2+WN0)-|h11|2(P2|hb2u2|2+PD2|hLI|2+WN0)＞0；
wherein the content of the first and second substances,
Figure FDA0003575523020000024
Figure FDA0003575523020000031
Figure FDA0003575523020000032
SE represents the subsystem spectral efficiency; w represents the channel bandwidth; p represents the solution parameter; rminWhen i is 1,2 is equal to
Figure FDA0003575523020000033
Figure FDA0003575523020000034
Representing a lowest tolerated information transfer rate of the first communication device; rminWhen i is 3,4 is equal to
Figure FDA0003575523020000035
Representing a lowest tolerated information transfer rate of the second communication device; p1Represents a transmission power, P, at which the base station transmits data to one of the D2D communication parties2Indicating a transmission power at which the base station transmits data to the other of the two D2D communication parties; pD1Representing the total transmission power, alpha, of said one device1And alpha2For a predetermined power division factor, alpha, of the one device1+α2＝1；PD2Representing the total transmission power, beta, of said other party's equipment1And beta2Is a preset power division factor, beta, of the other party's device1+β2＝1；
Figure FDA0003575523020000036
Represents the nominal transmission power of the base station,
Figure FDA0003575523020000037
representing a nominal transmit power of the first communication device; s.t. denotes the meaning to which it is bound; u. of1＝[u11,u12]TIndicating a precoding vector used when the base station transmits data to the one device; u. of2＝[u21,u22]TA precoding vector used when the base station transmits data to the other party device; h isb1Representing a channel parameter, h, from the base station to the one party deviceb2Represents a channel parameter from the base station to the other party device, [ h ]b1,hb2]T[u1,u2]I is an identity matrix, and superscript T represents matrix transposition; h isdRepresenting said one party device and said another partyChannel parameters between devices; h isLIRepresenting respective loop self-interference channel parameters of the one-party device and the other-party device; n is a radical of0A power spectral density representing additive white gaussian noise; h is11A channel parameter, h, representing the connection from said one device to a second communication device connected to the device12A channel parameter, h, representing a second communication device connected from said one device to said other device21A channel parameter, h, representing a second communication device connected from said other party's device to said one party's device22A channel parameter indicating a second communication device connected from the other party device to the one party device; k represents an iteration number mark when the convex optimization problem is solved by using an iterative algorithm; p1 k,
Figure FDA0003575523020000041
P at the k-th iteration1,P2,PD1,PD2The values substituted.
6. The system of claim 1, wherein the first communication device comprises a mobile terminal device supporting D2D communication and operating in a simultaneous co-frequency full duplex mode.
7. The system of claim 5, wherein a is α is n is α is n t n is n is n is n is n is n is n s n s n s n1＞α2And beta is1＞β2。
8. The spectrally efficient communication system employing D2D communication apparatus for relay forwarding according to claim 1 wherein said forwarding is transcoding forwarding.
9. The spectrally efficient communication system for relay forwarding with D2D communication devices of claim 3, wherein the neural network model comprises: and (3) a Radial Basis Function (RBF) neural network model.
10. The system according to claim 1, wherein the base station is a half-duplex base station, and the second communication device is a half-duplex mobile terminal device.
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Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR20140142643A (en) * 2013-06-04 2014-12-12 삼성전자주식회사 Method of controlling interference in a multi-hop network based on mimo system and a relay node and node pair enabling the method
CN106535284A (en) * 2016-12-12 2017-03-22 西安电子科技大学 Power control method in D2D communication based on full duplex relay

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR20140142643A (en) * 2013-06-04 2014-12-12 삼성전자주식회사 Method of controlling interference in a multi-hop network based on mimo system and a relay node and node pair enabling the method
CN106535284A (en) * 2016-12-12 2017-03-22 西安电子科技大学 Power control method in D2D communication based on full duplex relay

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
吴飞;邵士海;唐友喜;: "基于容量和发射机预调零的全双工天线位置优化研究", 电子与信息学报, no. 09, 31 December 2016 (2016-12-31) *
许尧: "基于 NOMA 的高谱效直传与中继协同传输 技术", 《博士学位论文电电子期刊》, 15 February 2022 (2022-02-15) *

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