CN114884550B - Relay cooperative transmission method for bidirectional transmission FD multi-relay cooperative SWIPT network - Google Patents

Relay cooperative transmission method for bidirectional transmission FD multi-relay cooperative SWIPT network Download PDF

Info

Publication number
CN114884550B
CN114884550B CN202210355020.5A CN202210355020A CN114884550B CN 114884550 B CN114884550 B CN 114884550B CN 202210355020 A CN202210355020 A CN 202210355020A CN 114884550 B CN114884550 B CN 114884550B
Authority
CN
China
Prior art keywords
relay
signal
optimal
coefficient
power
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Active
Application number
CN202210355020.5A
Other languages
Chinese (zh)
Other versions
CN114884550A (en
Inventor
徐友云
单永峰
蒋锐
李大鹏
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Nanjing University of Posts and Telecommunications
Original Assignee
Nanjing University of Posts and Telecommunications
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Nanjing University of Posts and Telecommunications filed Critical Nanjing University of Posts and Telecommunications
Priority to CN202210355020.5A priority Critical patent/CN114884550B/en
Publication of CN114884550A publication Critical patent/CN114884550A/en
Application granted granted Critical
Publication of CN114884550B publication Critical patent/CN114884550B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B7/00—Radio transmission systems, i.e. using radiation field
    • H04B7/14—Relay systems
    • H04B7/15—Active relay systems
    • H04B7/155—Ground-based stations
    • H04B7/15592—Adapting at the relay station communication parameters for supporting cooperative relaying, i.e. transmission of the same data via direct - and relayed path
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B7/00—Radio transmission systems, i.e. using radiation field
    • H04B7/14—Relay systems
    • H04B7/15—Active relay systems
    • H04B7/155—Ground-based stations
    • H04B7/15564—Relay station antennae loop interference reduction
    • H04B7/15585—Relay station antennae loop interference reduction by interference cancellation
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L5/00—Arrangements affording multiple use of the transmission path
    • H04L5/14—Two-way operation using the same type of signal, i.e. duplex
    • 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

Landscapes

  • Engineering & Computer Science (AREA)
  • Signal Processing (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Radio Relay Systems (AREA)

Abstract

The invention discloses a relay cooperative transmission method for a bidirectional transmission FD multi-relay cooperative SWIPT network, belonging to the technical field of calculation, calculation or counting. The invention is based on SWIPT receiver adopting dynamic PS strategy, uses single link interruption probability as optimization target, optimizes relay PS coefficient and simultaneously further optimizes signal power distribution coefficient of different frequency bands. Meanwhile, the performance and the application scene of various RS algorithms are analyzed by taking the bidirectional link traversal capacity and maximization as optimization targets. The relay node of the SWIPT receiver structure of the invention is selected to participate in bidirectional communication of the bidirectional transmission FD multi-relay cooperative SWIPT network, thereby realizing effective power distribution and improving the transmission efficiency of the system.

Description

Relay cooperative transmission method for bidirectional transmission FD multi-relay cooperative SWIPT network
Technical Field
The invention relates to a wireless information and energy simultaneous transmission technology, in particular discloses a relay cooperative transmission method for a bidirectional transmission FD multi-relay cooperative SWIPT network, which is suitable for wireless information and energy transmission of equipment such as an Internet of things node, a terminal node and the like with great difficulty in battery replacement or battery replacement, and belongs to the technical field of calculation, calculation or counting.
Background
Energy harvesting (EH, energy Harvesting) technology has become a solution to extend the life cycle of energy-limited wireless communication networks. Among the various energy sources, the energy carried by Radio Frequency (RF) signals is more stable and can be adaptively adjusted according to the system requirements. RF signals have been widely used as carriers for signals for wireless signal transmission (WIT, wireless Information Transfer), while RF signals are capable of carrying energy to enable wireless information and energy co-transmission (swit, simultaneous Wireless Information and Power Transfer) techniques.
However, the existing most advanced RF energy receiver cannot directly process the information carried by the signal, so researchers propose two practical strategies of Time Switching (TS) and Power Splitting (PS) to coordinate the operation of the information processing module (IP, information Processing) and EH module. In the TS strategy, the running time of the IP module and the running time of the EH module are staggered, the design and the implementation of a circuit are simpler, but the information transmission is discontinuous, and in order to adapt to the discontinuity of the information transmission, a signal transmitting end needs to adjust on signal coding so as to avoid transmitting useful signals in the running time of the EH module. The PS strategy then divides the received signal of the RF energy receiver into two parts in terms of power, one for the IP block and one for the EH block. The PS strategy solves the discontinuity of information transmission, better utilizes the time resources of the communication system, but at the same time increases the difficulty of circuit implementation of the RF energy receiver.
Relay cooperative communication is increasingly used in combination with the swift technology in order to expand the coverage of signals and improve the quality of communication services, due to problems such as path loss and multipath fading encountered by RF signals. In relay cooperative communication networks, the amplify-and-forward (AF, amplify and Forward) protocol and the decode-and-forward (DF, decode and Forward) protocol are two basic forwarding protocols. The DF protocol decodes the received signal at the relay and then forwards the decoded signal to the signal receiving end, and the decoding circuit filters the antenna noise included in the received signal, but also increases the power consumption at the relay. The AF forwarding protocol only carries out simple linear amplification processing on the received signal, and amplifies the useful signal power and the noise power at the same time. However, the AF forwarding protocol is simple to implement and does not require a decoding circuit with high power consumption. In the relay cooperative SWIPT network, the circuit running power of the relay is completely provided by the RF signal received by the relay, and in order to reduce the energy consumption of the relay, an AF forwarding protocol is adopted in actual application instead of a DF forwarding protocol which consumes more energy.
In the relay-cooperative swift network, EH relays can be classified into Half-Duplex (HD) EH relays and Full-Duplex (FD) EH relays according to operation mode division. When the EH relay operates in the HD mode, the transmission period of each communication is divided into two phases. In the first stage, the EH relays receive signals transmitted by the signal transmitting terminal, and in the second stage, the EH relays forward signals received in the first stage to the signal receiving terminal. When the EH relay operates in the FD mode, the EH relay forwards the received signal to the signal receiving terminal while receiving the signal transmitted by the signal transmitting terminal. Considering the influence of Self-Interference (SI) at the relay, early researches on relay cooperative networks have been focused on HD relay communication. In recent years, with the breakthrough of Self-interference cancellation (SIC, self-Interference Cancellation) technology, FD relay networks have gained a wide attention by virtue of their significant advantages in spectral efficiency compared to HD relay networks. Since the FD relay scheme based on the TS policy can transmit or receive information only for a part of the transmission period, the time resource utilization of the system is low. On the other hand, due to the breakthrough of SIC technology in recent years, the EH relay adopts a PS strategy, so that the EH module and the IP module can be well coordinated, and information can be continuously and simultaneously transmitted and received under the condition of not affecting the communication quality of the system. Thus, taking PS policies at EH relays can take full advantage of the FD characteristics of the system.
In a multi-Relay cooperative communication network, relay Selection (RS) can enhance the diversity gain of the system. The optimal relay is selected by adopting proper standards so as to optimize the system performance. Unlike conventional relay cooperative networks, in relay cooperative SWIPT networks, the signal transmit power at the relay is not limited by the battery capacity equipped by the relay itself, and the energy collected from the RF signal can support uninterrupted operation of the relay without battery or replacement of the battery. Thus selecting more relays not only does not consume additional battery power, but instead can collect more energy for signal forwarding. However, the greater the number of relays selected means that the less transmission bandwidth is allocated per relay, how to select a suitable set of relays to optimize system capacity is a hotspot of research.
In practical engineering applications, the use of a bidirectional relay network is unavoidable due to the need for traffic scenarios. Currently, research on bidirectional transmission FD multiple relay cooperative swift networks is mainly focused on common frequency full duplex transmission. In fact, in the bidirectional FD multi-relay cooperative network, due to the different distances between the two signal transmission sources and the relays and the different instantaneous channel states, the channel attenuation experienced by the signals transmitted by the two signal transmission sources when reaching the relays is inconsistent, which naturally causes the problem of power distribution of the mixed signals. Under the same-frequency full duplex relay transmission mechanism, as the signals of the two signal transmitting sources share the same frequency band, the separation operation of the mixed signals at the relay can not be performed, and thus the power distribution can not be completed.
In the prior art document, "Full-Duplex Wireless-Powered Relay in Two Way Cooperative Networks" (Full Duplex Wireless power supply relay in a bidirectional cooperative network, "" IEEE Access, vol.5, pp.1548-1558,2017 "") considers the scenario of signal bidirectional transmission in a multi-relay cooperative switch network, but mainly focuses on researching the difference, the switch receiver policy has an effect on system throughput and outage probability, and takes the same-frequency Full Duplex transmission as a research background, mixed signals are not separated at the relay, and the capability of distinguishing and separating the mixed signals through frequency bands is not provided, so that power distribution cannot be realized; in addition, "Time-Switching Based In-Band Full Duplex Wireless Powered Two-Way Relay" (in-band full duplex wireless power supply bidirectional Relay based on Time switching), "2016 URSI Asia-Pacific Radio Science Conference, pp.438-441,2016" one considers the scene of signal bidirectional transmission in single Relay cooperative SWIPT network, proposes a Relay forwarding protocol capable of processing same frequency self-interference, but adopts a TS strategy with lower Time slot utilization, and still uses same frequency full duplex transmission as research background, and cannot perform separation operation of mixed signals at the Relay.
Disclosure of Invention
The invention aims to solve the technical problems of separation and power redistribution of mixed signals in a bidirectional transmission FD relay cooperative SWIPT network by redesigning the SWIPT receiver structure at a relay to support frequency division duplex (Frequency Division Duplex, FDD) communication, and provides a relay cooperative transmission method for the bidirectional transmission FD multi-relay cooperative SWIPT network, namely when a certain relay is selected for cooperative communication, the relay separates information waveform signals output by a PS strategy through a band-pass filter, respectively extracts signals corresponding to two signal source frequency bands, the relay performs power distribution on electric energy stored by energy waveform signals output by the PS strategy again, obtains an optimal PS coefficient and an optimal power distribution coefficient by taking the minimum probability of single link interruption as an optimization target, and the two power parts after the redistribution are respectively used for power amplification of signals of two signal source frequency bands so as to realize the purposes of separating different frequency band signals and optimal power distribution in the mixed signals.
The invention adopts the following technical scheme for realizing the purposes of the invention:
according to the relay cooperative transmission method for the bidirectional transmission FD multi-relay cooperative SWIPT network, by designing the SWIPT receiver capable of supporting FDD communication and applying the SWIPT receiver to the bidirectional transmission FD multi-relay cooperative SWIPT network, signals in different frequency bands can be separated at relays and power can be redistributed.
Further, in a relay cooperative transmission method for a bidirectional transmission FD multi-relay cooperative switch network, a switch receiver supporting FDD communication includes:
the power dividing module receives the mixed signal from the two signal sources, divides the mixed signal into two parts according to the PS coefficient of the current relay and outputsPart of the mixed signal is sent to an IP module to output +.>Partial mixed messageNumber to EH module, ρ j PS coefficient ρ for jth relay j ∈[0,1]；
IP block for receivingDemodulating part of the mixed signal from said +.>Separating and extracting signals from two signal sources from part of mixed signals, amplifying the signals from the two signal sources, and outputting frequency band signals from the two signal sources;
EH module, receivePart of the mixed signal, will->Converting part of the mixed signals into direct-current electric energy and storing the direct-current electric energy into a battery module; the method comprises the steps of,
and the power distribution module is used for distributing power of the direct current electric energy stored in the battery module according to the current relay power distribution coefficient and transmitting the frequency band signals from the two signal sources to the corresponding signal sources according to the distributed power.
Further, in the relay cooperative transmission method of the FD multi-relay cooperative SWIPT network facing the bidirectional transmission, the selected relay R is selected j Information waveform signal separated by PS strategyFurther adopts a band-pass filter to separate, and hasFor separating extracted signals from the signal source S by means of a band-pass filter i (i=1, 2) i (i=1, 2) signal ρ j For relaying R j Dynamic PS coefficient at h ij Is a signal source S i And relay R j Channel response between->Representative signal source S i Is>For relaying R j Residual self-interference channel response at +.>For relaying R j Corresponding to the signal source S in the transmitted signal i (i=1, 2) part of the signal band.
Further, in the relay cooperative transmission method of the FD multi-relay cooperative switch network facing the bidirectional transmission, the relay R is selected j Energy waveform signals separated by PS strategyAfter entering the EH module, the power is converted into direct-current electric energy to be stored in the battery module, and the relay R is used for j The total emission power that can be provided by the battery module of (a) is recorded as +.>The power distribution module will be right->Reassigning, setting the system to adjust the power distribution coefficient to +.>Due to->The method comprises the following steps:for relaying R j Total transmit power->Is used for a signal source S 1 Power part of band signal, ">For relaying R j Total transmit power->Is used for a signal source S 2 Power part s of frequency band signal j For relaying R j Is used for the power distribution coefficient of the power supply.
Still further, in the relay cooperative transmission method of the FD multi-relay cooperative switch network for bidirectional transmission, the final selected relay R is calculated j Forwarded and transmitted by signal source S i (i=1, 2) signal-to-noise ratio after reception processing isOr->Wherein, the liquid crystal display device comprises a liquid crystal display device,for relaying R j For signal source->Amplification of frequency band signal, < >>For relaying R j Variance of additive white gaussian noise introduced at band pass filter i (i=1, 2), +.>Representing signal source S i (i=1, 2) the variance of additive gaussian white noise at the receive antenna end.
Furthermore, in the relay cooperative transmission method of the bidirectional transmission FD multi-relay cooperative SWIPT network, the method comprises the following steps ofSolving relay R for objective function j Optimal PS coefficient at->And optimal power allocation coefficient->The method comprises the following steps: />Wherein, the liquid crystal display device comprises a liquid crystal display device,s for the currently selected relay set R Is the original selected relay set.
Compared with the prior art, the invention has the following beneficial effects:
(1) According to the invention, the SWIPT receiver structure supporting FDD communication is designed at the relay, and the SWIPT network can adaptively adjust the power distribution coefficient according to different channel conditions by realizing signal separation operation of signals with different signal source frequency bands and completing power redistribution operation after signal separation, so that adaptive response is made to dynamic channel weakness of mixed signals at the relay in the multi-relay cooperative network.
(2) On the basis of a relay node of a SWIPT receiver structure, the invention determines the optimal PS system and the power distribution coefficient of the relay by taking the minimum probability of unidirectional link interruption as a target, and selects the relay participating in the bidirectional communication by taking the maximum sum of the traversing capacities of the bidirectional links as a target.
(3) The relay of the SWIPT receiver structure adopted by the invention can separate the self-interference signal, and the separated self-interference signal and the signal source transmitting signal are amplified and distributed together, so that the relay node can be flexibly applied to a relay network of which the signal receiving and transmitting end can support FDD communication, and the self-interference of each node in the relay network is effectively inhibited.
Drawings
Fig. 1 is a topology diagram of a bi-directional transmission FD AF multi-relay cooperative swift network model based on PS policies.
Fig. 2 is a schematic diagram of a swift receiver inside a relay node.
Fig. 3 is a graph of traversal capacity and comparison of different RS algorithms.
Fig. 4 is a graph comparing outage probabilities for different RS algorithms.
Fig. 5 is a schematic diagram of selecting the number of relays in the GRS algorithm.
Detailed Description
The relay cooperative transmission method for the bidirectional transmission FD multi-relay cooperative SWIPT network provided by the invention designs a relay cooperative transmission scheme based on an FDD mechanism, redesigns the SWIPT receiver structure at the relay to support FDD communication, redistributes power after the separation operation of signals in different frequency bands is completed, takes the minimum probability of single link interruption as an optimization target, obtains an optimal PS coefficient and an optimal power distribution coefficient, and analyzes the performances of a plurality of RS algorithms based on the optimal PS coefficient and the optimal power distribution coefficient. The theoretical derivation of the technical solution of the invention is described in detail below with reference to fig. 1 to 3.
Consider a PS policy based two-way transmission dual-hop FD AF multi-relay cooperative swift network model as shown in fig. 1. Assume a total of N operational relays R in the network 1 ,R 2 ,……,R N And two signal sources S with information encoding and decoding functions 1 ,S 2 And each relay is a swift receiver with an energy harvesting function. Each relay is set to be of passive design, i.e. the power consumed by the relay in operation is all derived from the energy collected by itself in the RF signal. All nodes comprising two signal sources are operated in the FD mode, and meanwhile, in order to avoid signal interference generated between relays in the FD mode, each selected relay is operated in an incoherent frequency range by adopting a mode of dividing the total bandwidth of the system in equal frequency bands. Assume a signal source S 1 And signal source S 2 Between them do not haveReachable, so direct links are not considered. Is provided withRepresenting the set of selected relays, the total bandwidth available to the network is B, |·| operator represents the basis of one set, and the channel bandwidth allocated by each selected relay is +.>Assuming that the channels of all links in the multi-relay cooperative network are Rayleigh fading channels, and transmitting a signal source S i (i=1, 2) and relay R j The channel response between (j=1, 2,., N) is noted as h ij 。
Fig. 2 shows a structural model of a relay node swift receiver capable of supporting FDD communication according to the present invention. Relay R j The residual self-interference (RSI) channel response at this point is noted asUnder the bidirectional communication scene set by the invention, two signal sources S 1 And S is 2 All operate in FD mode, thus signal source S 1 And S is 2 Self-interference at the position also needs to be considered, and the signal source S is used for i The RSI channel response at this point is denoted +.>Assuming that the Channel State Information (CSI) of all channels is completely known to the signal source, the system will dynamically select an "optimal" relay set to maximize the system capacity based on the instantaneous and randomness of the CSI when applying the corresponding RS algorithm. To simplify the analysis, the power consumed by the internal circuitry of the relay and the signal processing during the CSI acquisition stage is ignored.
During relay network operation, relay R j When selected, relay R j Will receive the signal from the signal source S 1 Sum signal source S 2 Simultaneously, the processed mixed signals are respectively forwarded to the signal source S in a broadcast mode 1 And S is 2 . Each signal source is receivingAfter mixing the signals, signals from another source are separated and extracted, and the forwarded signals from the plurality of selected relays are processed by using a Maximum Ratio Combining (MRC) diversity reception mode. Selected relay R j The received mixed signal is processed according to PS coefficient ρ j :(1-ρ j ) Divided into two parts, wherein ρ j Part of the solution enters an IP module, 1- ρ j Part of the way into the EH module. After demodulation, the part entering the IP module is filtered by the band-pass filter 1 and the band-pass filter 2 to obtain signal sources S belonging to different frequency bands 1 And S is 2 And then amplifying the signals of the two different frequency bands by using an AF protocol. The signal entering the EH module is converted into DC electric energy by the internal circuit in the form of energy waveform and temporarily stored in the battery module, and then the relay internal part redistributes the power of the energy stored in the battery for the signal source S 1 Frequency band signal and signal source S 2 Power amplification of the band signal. The following derives the analytical expressions of the system traversal capacity and outage probability under the FDD-based relay cooperative transmission scheme proposed by the present invention and typically explains the concept of the RS algorithm with the greedy relay selection (GRS, greedy Relay Selection) algorithm.
(1) Relay cooperative transmission scheme based on FDD
During network operation, relay R j When selected, R j The mixed signal received at this point can be expressed as:
wherein, the liquid crystal display device comprises a liquid crystal display device,for relaying R j A received signal at h ij Is a signal source S i And relay R j The response of the channel between them,representative ofSignal source S i Is>For relaying R j RSI channel response at ∈>For relaying R j Transmit signal at>For relaying R j Antenna noise at->Obeying the mean value to be 0, variance to be +.>Complex gaussian distribution of (c)Wherein (1)>N A Represents a relay R j Noise power spectral density at receiving antenna, [ n ]]Representing the time domain.
Relay R j Received from a signal source S 1 And S is 2 After the mixed signal of (2) will be according to PS coefficients: ρ j :(1-ρ j ),ρ j ∈[0,1]The system is divided into two parts, and the two parts are respectively conveyed to an IP module and an EH module, as follows:
firstly, the mixed signals enter an IP module to complete signal demodulation, then the band-pass filter 1 and the band-pass filter 2 separate the mixed signals according to different frequency bands, and the adopted frequency bands respectively correspond to a signal source S 1 And S is 2 I.e. the band-pass filter i (i=1, 2) separates the extracted signal as coming from the source S i The signal of (i=1, 2) will be relayed R j The signal extracted at band-pass filter i (i=1, 2) is split and denoted +.>The method comprises the following steps:
wherein the signalFor relaying R j Transmitted signal +.>Corresponding to the signal source S i (i=1, 2) part of the signal band, consider in the actual circuitry the signal +.>The duty cycle of the useful signal is small compared with the thermal noise, namely:
the system then separates the extracted signal from the band-pass filter i (i=1, 2)Amplifying by AF protocol, recording relay R j For a signal source S i The amplification factor of the (i=1, 2) band signal is +.>The method comprises the following steps:
in formula (6), the signalFor the system to come from signal source S i Output signal of amplified (i=1, 2) band signal, +.>Represents a relay R j Additive White Gaussian Noise (AWGN) introduced at bandpass filter i (i=1, 2), obeying a mean of 0, variance +.>Complex gaussian distribution ∈ ->Wherein, the liquid crystal display device comprises a liquid crystal display device,represents a relay R j Noise power spectral density of the internal circuitry.
Due to the signalThe medium noise is very small in proportion>Formula (6) is again rewritable:
then relay R j Corresponding to that from signal source S to be provided i Transmit power of (i=1, 2) band signalThe method comprises the following steps:
to simplify the analysis, two signal sources S are set 1 And S is 2 The signal transmitting power of (2) is P S The method comprises the following steps:consider formula (8) as pertaining to the variable +.>Is solved by the unitary equation of (1):
relay R j The total transmit power required to be provided isWhich are driven entirely by the electric energy stored in the battery modules, respectively for the signal sources S 1 And S is 2 The power amplification of the frequency band signal includes:
signal in (3)After entering the EH module, the energy is converted into direct-current electric energy and stored in the battery module, and when the energy collection efficiency of the EH module is xi, the relay R is formed j Total transmit power which can be provided +.>The value of (2) can be expressed as:
regarding formula (11) as a variableIs solved by the unitary equation of (1):
signal signalAfter entering the EH module, the EH module is converted into direct-current electric energy to be stored in the battery module, then the power distribution module redistributes the electric energy in the battery module in power, and the system is set to adjust the power distribution coefficient to be equal toA simultaneous (10) having the following equation:
solving the equation set, one can obtain:
in the formula (9)And formula (12) are substituted into formula (14), respectively>Andsolving for variables respectively>And variable->Is given by the unitary equation:
via relay R j Forwarded and transmitted by signal source S i The received signal of (i=1, 2) can be expressed as:
wherein, the liquid crystal display device comprises a liquid crystal display device,is a signal source S i RSI channel response at (i=1, 2), and w ij [n](i=1, 2) represents the relay R j Operating in the frequency range of the signal source S i (i=1, 2) AWGN at the receive antenna end, subject to a mean of 0, variance +.>Complex gaussian distribution->Wherein (1)>N S Representing signal source S i (i=1, 2) noise power spectral density at the receive antenna end.
Then via relay R j Forwarded and transmitted by signal source S i The received signal power of (i=1, 2) can be calculated as:
given by the formula (8)Substituted formula (18),>can be expressed as:
wherein when i=1, 2, there areSignal source S i (i=1, 2) as a transceiver supporting FDD communication, signals in the same frequency band as the signals transmitted by the transceiver are filtered out when the signals are received, namely, the first, second, third and seventh signal components in the formula (19) are filtered out, and the corresponding other end signal source is->The useful signals of the transmission signal frequency band are a fourth signal component, a fifth signal component, a sixth signal component and an eighth signal component are noise components, wherein +.>The components passing through the signal source S i (i=1, 2) the receiver will become +.>Thus, a relayed R is obtained j Forwarded and transmitted by signal source S i (i=1, 2) the signal-to-noise ratio after the reception process is:
or->
In the formula (20), the amino acid sequence of the compound,the value of (2) is given by the formula (15) or the formula (16), and +.>The value of (2) can be given by the formula (14) and the formula (12).
Finally, signal source S i (i=1, 2) processing signal samples from a plurality of forwarding relays using MRC diversity reception,the channel capacity of a link can be expressed as:
(2) Relay selection problem modeling
In the formula (21), the amino acid sequence of the amino acid,the present invention mainly considers S when evaluating the performance of different relay selection algorithms 1 -S 2 Link and S 2 -S 1 And the sum of the link traversal capacity and the outage probability. Wherein S is 1 -S 2 Link and S 2 -S 1 The sum of link traversal capacities can be expressed as:
the outage probability may be defined as:
wherein C is th For interruption threshold of channel capacity, ifBelow this value the communication is considered to be interrupted.
Different criteria may select different relays when comparing who is better between the relays. The invention relates to a bidirectional transmission relay cooperative network based on an FDD mechanism, which considers the power distribution problem of signals of two signal sources at a relay, and if the signal to noise ratio or the channel capacity of the relay participating in cooperation is adopted as an index to optimize and the optimal relay is selected, the optimal power distribution coefficient at the relay is seriously unbalanced, namely, the signal sent by one of the two signal sources is not effectively forwarded, which is contrary to the scene setting of the bidirectional transmission relay network. To maintain S in a two-way transmission scenario 1 -S 2 Link and S 2 -S 1 The invention still uses the channel capacity of the relay participating in the cooperative communication as a standard for judging the relay quality, but uses the interruption probability of the relay participating in the cooperative communication as an objective function when solving the optimal PS coefficient and the optimal power distribution coefficient. Based on equation (21), relay R j Engaging in collaborative communicationsThe channel capacity of a link can be noted asWherein (1)>For relaying R j Joining original relay set S R The selected relay set in the future, k represents the selected relay set +.>The kth selected relay, then relay R j Participation in collaborative communication disruptionThe rate can be defined as:
first, with outage probabilityAnd the minimum is an optimization target, and an optimal PS coefficient and an optimal power distribution coefficient are obtained. From the formulae (24) and (21), it is easily analyzed that the break probability is minimized>Equivalent to maximize +.>That is equivalent to maximize +.>Relay R j The objective function to be optimized for participating in collaborative communication isWherein->For relaying R j Joining an original selected relay set S R The selected relay set is then relayed R j Optimal PS coefficient at->And optimal power allocation coefficient->The method comprises the following steps:
then, to relay R j Bi-directional participation in collaborative communicationsSum of link channel capacitiesAs a criterion for judging the relay quality, the subscript of a single optimal relay selected from the relay set with the relay number of N is:
wherein the method comprises the steps ofAnd->Calculated from equation (25).
Several common RS algorithms are single relay selection (SRS, single Relay Selection) algorithm, all relay (AP) algorithm, greedy relay selection (GRS, greedy Relay Selection) algorithm, and exhaustive search (ES, exhaustive Search) algorithm. Wherein, the AP algorithm selects all relays to carry out cooperative communication; whereas SRS algorithms are essentially special cases where the GRS algorithm selects only one "optimal" relay in the first step; although the ES algorithm can achieve the truly optimal performance, when the number of the optional relays is large, the algorithm complexity is huge, and the ES algorithm cannot be practically applied. The GRS algorithm can obtain almost the same performance as the optimal ES algorithm on the average capacity of the system, and has lower algorithm complexity, and can meet the real-time processing requirement, so the GRS algorithm is widely applied in practice. The relay cooperative transmission method will be described below with the GRS algorithm as an implementation algorithm.
(3) Greedy relay selection algorithm
In a relay network with N relay numbers, a Greedy Relay Selection (GRS) algorithm is divided into N steps, and the initial state of a relay set is thatSelected Relay set after the end of step n +.>Can be expressed as:
wherein the method comprises the steps ofFor the n-th step selected from the remaining selectable relay sets for joining the relay set +.>The subscripts of the optimal relay of (1) are:
wherein the method comprises the steps ofAnd->Can be represented by formula (25)>The following calculation results.
At the position ofSelecting the optimal relay set->The method comprises the following steps:
the following describes performance and application scenarios of three RS algorithms, namely an SRS algorithm, an AP algorithm and a GRS algorithm, in the relay cooperative transmission method according to the present invention, with reference to three numerical simulation diagrams of fig. 3 to 5. It will be apparent that the described embodiments are only some, but not all, embodiments of the invention. All other embodiments of the same inventive concept, which are obtained by those skilled in the art based on the embodiments of the present invention, fall within the scope of the present invention. All radio link channels were modeled using the rayleigh Li Cuiruo channel and the main parameters used in the simulation are listed in table 1.
Table 1 list of simulation parameters
System bandwidth 10MHz
Noise power spectral density -174dBm/Hz
Energy Harvesting (EH) efficiency 90％
Residual self-interference (RSI) channel gain -80dB
Relay number of relay set to be selected 3 or 8
Spectral efficiency outage threshold 0.5bps/Hz
Fig. 3 compares the sum of the two-way link traversal capacities of different RS algorithms under the relay cooperative transmission scheme based on the FDD mechanism proposed by the present invention, and discusses two cases where the number of relays in the network is 3 and 8. In the framework of the bi-directional relay network of the present invention, the GRS algorithm still achieves almost complete performance close to the ES algorithm, so no presentation or analysis of the ES algorithm is made here. The performance of the ES algorithm represents the optimal performance of the system, but the GRS algorithm with lower algorithm complexity represents the optimal performance of the system because the algorithm complexity is too high to be practical. It is also known from fig. 3 that the GRS algorithm traverses capacity sums over all source transmit power coordinates above the AP algorithm and SRS algorithm.
Looking at fig. 3, when the source transmit power is low, the AP algorithm obtains a sum of traversal capacities similar to the GRS algorithm representing the optimal performance and greatly leads the sum of traversal capacities of the SRS algorithm, since the AP algorithm selects all relays to collect more energy, generates more signal copies, and finally strengthens the received signal-to-noise ratio at the two signal sources. It can also be seen from fig. 5 that the GRS algorithm will select a relatively large number of relays at low source transmit power. In view of the extremely low algorithm complexity of the AP, the system typically enables the AP algorithm at low source transmit power. However, as the source transmit power increases, the performance of the AP algorithm is increasingly behind that of the GRS algorithm and SRS algorithm. This is because at higher source transmit power, a single optimal relay is already able to collect considerable energy for signaling itself, and at this time, only a single optimal relay is selected to fully and effectively utilize the system bandwidth, so GRS algorithms will also tend to select a single optimal relay to achieve the system optimal performance at higher source transmit power, and the system will typically enable SRS algorithms at higher source transmit power, given the very low linear complexity of SRS algorithms. Similarly, as the number of hops increases from 3 to 8, the sum of the traversal capacities of the AP algorithm increases at low source transmit powers, while the sum of the traversal capacities decreases at high source transmit powers. In summary, the SRS algorithm and the AP algorithm obtain near-optimal sum of traversal capacities at high source transmit power and low source transmit power, respectively, and have extremely low algorithm complexity.
Furthermore, the SRS algorithm has a significant performance improvement at low source transmit power while the SRS algorithm has a very limited performance improvement at high source transmit power when the number of relays increases from 3 to 8. This is because the increase in the number of relays provides more channel state possibilities at low source transmit power, and the probability of being able to select a better relay becomes greater, while the high source transmit power compensates for the defect of channel state fluctuations. The GRS algorithm benefits from a more or less increase in the number of relays over all source transmit power intervals, similar to the SRS algorithm, with less traversal capacity and boosting at high source transmit power. In summary, at low source transmit power, the AP algorithm, SRS algorithm and GRS algorithm can all benefit significantly from the increase in the number of relays, while at high source transmit power only the GRS algorithm can obtain smaller performance gain from the increase in the number of relays, SRS algorithm is hardly affected, and AP algorithm obtains even lower sum of traversal capacities.
Fig. 4 compares outage probabilities of different RS algorithms under the relay cooperative transmission scheme based on the FDD mechanism proposed by the present invention, and also considers two cases of 3 and 8 relay numbers in the network. Unlike the SRS algorithm traversal capacity and the advanced AP algorithm at high source transmit power in fig. 3, the SRS algorithm is instead weaker than the AP algorithm in terms of performance of outage probability. This results from the relation between SRS algorithm and AP algorithmOn the premise that the frequency spectrum efficiency interruption threshold set by simulation parameters is 0.5bps/Hz, SRS algorithm is +.>The probability of (a) is greater than that under the AP algorithm When the relay number is increased from 3 to 8, the interrupt performance of the SRS algorithm, the AP algorithm and the GRS algorithm is obviously improved, and the AP algorithm and the GRS algorithm benefit from the increase of the relay number due to the fact that the relay number selected by the AP algorithm and the GRS algorithm under lower source transmission power is more, so that the SRS algorithm and the GRS algorithm can be improved greatlyThe performance improvement of the method is already obvious at lower source transmit powers. Therefore, when the designed relay network has high requirements on interrupt performance, the relay network can be realized by increasing the relay quantity and preferentially using the AP algorithm and the GRS algorithm, and if the AP algorithm has similar performance to the GRS algorithm, the AP algorithm with extremely low algorithm complexity can be considered to be used. Furthermore, in fig. 3, the SRS algorithm with the number of relays 8 obtains a higher sum of traversal capacities over all source transmit power intervals than the GRS algorithm with the number of relays 3, and in fig. 4, when the source transmit power exceeds 25dB, the SRS algorithm with the number of relays 8 also exceeds the GRS algorithm with the number of relays 3 in outage performance, which indicates that the number of relays has a great influence on system performance, and if the designed relay network budget is sufficient, more relays should be arranged as much as possible.
Fig. 5 depicts the variation of the selected number of relays with source transmit power for GRS algorithm representing the optimal performance of the system for relay numbers 3 and 8, respectively. Consistent with the previous analysis, GRS algorithms tend to select a greater number of relays at low source transmit power, and a number of relays that tend to be 1 at higher source transmit power. At a source transmit power of 0dB, the GRS algorithm with a relay number of 3 selects a relay number close to 3, the utilization of the relay is close to saturation, while the GRS algorithm with a relay number of 8 selects only a relay number close to 6, and the utilization of the relay is only 75%, which indicates that when the relay number increases to a certain extent, the channel diversity between different relays is enough, and it is not preferable to blindly increase the system performance by increasing the relay number. In addition, fig. 5 also shows that when the source transmit power starts to exceed about 17dB, the number of relays required for the GRS algorithm with the relay number of 8 becomes smaller than that for the GRS algorithm with the relay number of 3, which means that when the source transmit power reaches a certain level, the number of relays selected by both is smaller, and the former can achieve the optimal performance of the system by virtue of richer channel diversity, only fewer relays need to be selected.

Claims (4)

1. The relay cooperative transmission method for the bidirectional transmission FD multi-relay cooperative SWIPT network is characterized in that each relay in the bidirectional transmission FD (Full-Duplex) multi-relay cooperative SWIPT network is a SWIPT receiver supporting FDD communication, for a link between two signal sources working in different frequency bands in the bidirectional transmission FD multi-relay cooperative SWIPT network, the optimal PS (Power Splitting) coefficient and the optimal power distribution coefficient at each relay are determined by taking the minimum probability of unidirectional link interruption as a target, the sum of the traversing capacity of the bidirectional link is the maximum target, and the optimal relay participating in the bidirectional link communication is selected according to the optimal PS coefficient and the optimal power distribution coefficient at each relay;
the SWIPT receiver supporting FDD communication comprises:
the power dividing module receives the mixed signal from the two signal sources, divides the mixed signal into two parts according to the PS coefficient of the current relay and outputsPart of the mixed signal is sent to an IP module to output +.>Part of the mixed signal is sent to an EH module, ρ j PS coefficient ρ for jth relay j ∈[0,1]，
IP block for receivingDemodulating part of the mixed signal from said +.>Separating and extracting signals from two signal sources from part of mixed signals, amplifying the signals from the two signal sources, outputting frequency band signals from the two signal sources,
EH module, receivePart of the mixed signal, will->Part of the mixed signal is converted into direct current electric energy and then stored in the battery module, and,
and the power distribution module is used for distributing power of the direct current electric energy stored in the battery module according to the current relay power distribution coefficient and transmitting the frequency band signals from the two signal sources to the corresponding signal sources according to the distributed power.
2. The relay cooperative transmission method for bidirectional transmission FD multiple relay cooperative swit network according to claim 1, wherein the following steps are performedPart of the mixed signal isSaid->Part of the mixed signal isWherein (1)>Respectively the time domains [ n ]]Mixed signal received by IP module and EH module in inner jth relay +.>Is the time domain [ n ]]Hybrid signal from two signal sources received by power distribution module in inner jth relay, h ij For the ith signal source S i With the j-th relay R j Channel response between->Is the time domain [ n ]]Inner ith signal source S i Is>For the j-th relay R j RSI channel response at ∈>Is the time domain [ n ]]Inner jth relay R j Transmit signal at>Is the time domain [ n ]]Inner jth relay R j Antenna noise at->Obeying the mean value to be 0, variance to be +.>Complex gaussian distribution->N A For the j-th relay R j Noise power spectral density at receiving antenna, B is total bandwidth of the bidirectional transmission FD-oriented multi-relay cooperative swift network, +.>For the j-th relay R j Joining an original selected relay set S R The selected relay set of later +.>
3. The relay cooperative transmission method for a bidirectional transmission FD multi-relay cooperative swift network according to claim 2, wherein the expression for determining the optimal PS coefficient and the optimal power allocation coefficient at each relay with the minimum probability of unidirectional link interruption as a target is:wherein (1)>Optimal PS coefficient and optimal power allocation coefficient for jth relay, s j Power allocation coefficient for jth relay, < >>A unidirectional link outage probability for the jth relay to participate in the bi-directional communication,for the signal to noise ratio of the signal forwarded via the jth relay and received by the 1 st signal source>For the signal to noise ratio of the signal forwarded via the j-th relay and received by the 2 nd signal source>Or (b)For the signal-to-noise ratio of the signal forwarded via the jth relay and received by the ith signal source>Is the reference number of the other of the two signal sources with respect to the ith signal source, +.>For the j-th relay R j For a signal source S i Amplification factor of frequency band signal, P S For the transmission power of the signal source, +.>For the j-th relay R j Provided corresponding to the signal from the signal source S i Transmit power of band signal, < >>For the j-th relay R j Variance of complex gaussian distribution obeyed by additive white gaussian noise introduced by band-pass filter for separating radio frequency signals corresponding to signal source frequency band signals +.>For the j-th relay R j Noise power spectral density of internal circuit +.>To be in the jth relay R j Variance of complex gaussian distribution obeyed by additive gaussian white noise acting on signal source receiving antenna end in working range +.>N S The noise power spectral density of the antenna end is received for the signal source.
4. A relay cooperative transmission method for a bidirectional FD multiple relay cooperative swift network according to claim 3, wherein the expression that targets the sum of bidirectional link traversal capacities and selects an optimal relay to participate in bidirectional link communication according to an optimal PS coefficient and an optimal power allocation coefficient at each relay is:wherein j is * The index of the optimal relay, N is the relay set { R } j Number of relays in }, +.>For the j-th relay to be the mostSum of bi-directional link traversal capacities of optimal PS coefficients and optimal power allocation coefficients for participation in bi-directional communication, +.>The sum of the bi-directional link traversal capacities for the j-th relay to participate in bi-directional communication>k represents the selected relay set +.>Is the kth selected relay.
CN202210355020.5A 2022-04-06 2022-04-06 Relay cooperative transmission method for bidirectional transmission FD multi-relay cooperative SWIPT network Active CN114884550B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202210355020.5A CN114884550B (en) 2022-04-06 2022-04-06 Relay cooperative transmission method for bidirectional transmission FD multi-relay cooperative SWIPT network

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202210355020.5A CN114884550B (en) 2022-04-06 2022-04-06 Relay cooperative transmission method for bidirectional transmission FD multi-relay cooperative SWIPT network

Publications (2)

Publication Number Publication Date
CN114884550A CN114884550A (en) 2022-08-09
CN114884550B true CN114884550B (en) 2023-07-25

Family

ID=82670506

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202210355020.5A Active CN114884550B (en) 2022-04-06 2022-04-06 Relay cooperative transmission method for bidirectional transmission FD multi-relay cooperative SWIPT network

Country Status (1)

Country Link
CN (1) CN114884550B (en)

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN117560049A (en) * 2023-05-11 2024-02-13 武汉能钠智能装备技术股份有限公司四川省成都市分公司 Satellite ground station relay forwarding system

Citations (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN106788620A (en) * 2016-12-02 2017-05-31 哈尔滨工程大学 A kind of distributed relay selection for minimizing outage probability and user power allocation method
CN108811025A (en) * 2018-05-23 2018-11-13 南京邮电大学 It is a kind of that the transmission plan that cooperates can be communicated based on wirelessly taking for relaying energy storage
CN109302250A (en) * 2018-09-13 2019-02-01 西安交通大学 Energy transmission full duplex relaying carries out relay selection and power distribution method
US10361596B1 (en) * 2018-08-29 2019-07-23 King Fahd University Of Petroleum And Minerals Protocol, method and system for simultaneous wireless information and power transfer relaying network
CN110062377A (en) * 2019-03-22 2019-07-26 杭州电子科技大学 Power splitting factor and beam forming combined optimization method in capable of communicating are taken safely
CN111542121A (en) * 2020-05-08 2020-08-14 重庆理工大学 Multidimensional resource allocation method meeting SWIPT and applied to bidirectional DF relay system
CN111988802A (en) * 2020-08-28 2020-11-24 天津工业大学 Allowable delay transmission method in SWIPT (switched wire power over IP) bidirectional transmission relay system based on PS (packet switched) strategy
CN111988804A (en) * 2020-08-28 2020-11-24 天津工业大学 Throughput optimization method in direct link-containing SWIPT relay system based on PS strategy
CN112073093A (en) * 2020-09-09 2020-12-11 天津工业大学 PS strategy-based delay-limited transmission method in SWIPT bidirectional transmission relay system
CN113207185A (en) * 2021-04-28 2021-08-03 中山大学 Resource optimization allocation method of wireless energy-carrying OFDM (orthogonal frequency division multiplexing) cooperative relay communication system
CN113490238A (en) * 2021-05-31 2021-10-08 南京邮电大学 Relay selection optimization method for FD multi-relay cooperation SWIPT network

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7684337B2 (en) * 2006-01-17 2010-03-23 Mitsubishi Electric Research Laboratories, Inc. Method and system for communicating in cooperative relay networks
CN102083217A (en) * 2009-11-26 2011-06-01 华为技术有限公司 Resource distribution method and device for multi-relay orthogonal frequency division multiplexing system
KR101816613B1 (en) * 2016-04-22 2018-01-09 성균관대학교산학협력단 Full-duplex relay communication method based on energy harvesting and full-duplex relay communication system based on energy harvesting

Patent Citations (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN106788620A (en) * 2016-12-02 2017-05-31 哈尔滨工程大学 A kind of distributed relay selection for minimizing outage probability and user power allocation method
CN108811025A (en) * 2018-05-23 2018-11-13 南京邮电大学 It is a kind of that the transmission plan that cooperates can be communicated based on wirelessly taking for relaying energy storage
US10361596B1 (en) * 2018-08-29 2019-07-23 King Fahd University Of Petroleum And Minerals Protocol, method and system for simultaneous wireless information and power transfer relaying network
CN109302250A (en) * 2018-09-13 2019-02-01 西安交通大学 Energy transmission full duplex relaying carries out relay selection and power distribution method
CN110062377A (en) * 2019-03-22 2019-07-26 杭州电子科技大学 Power splitting factor and beam forming combined optimization method in capable of communicating are taken safely
CN111542121A (en) * 2020-05-08 2020-08-14 重庆理工大学 Multidimensional resource allocation method meeting SWIPT and applied to bidirectional DF relay system
CN111988802A (en) * 2020-08-28 2020-11-24 天津工业大学 Allowable delay transmission method in SWIPT (switched wire power over IP) bidirectional transmission relay system based on PS (packet switched) strategy
CN111988804A (en) * 2020-08-28 2020-11-24 天津工业大学 Throughput optimization method in direct link-containing SWIPT relay system based on PS strategy
CN112073093A (en) * 2020-09-09 2020-12-11 天津工业大学 PS strategy-based delay-limited transmission method in SWIPT bidirectional transmission relay system
CN113207185A (en) * 2021-04-28 2021-08-03 中山大学 Resource optimization allocation method of wireless energy-carrying OFDM (orthogonal frequency division multiplexing) cooperative relay communication system
CN113490238A (en) * 2021-05-31 2021-10-08 南京邮电大学 Relay selection optimization method for FD multi-relay cooperation SWIPT network

Non-Patent Citations (4)

* Cited by examiner, † Cited by third party
Title
Power Splitting-Based SWIPT With Dual-Hop DF Relaying in the Presence of a Direct Link;Yinghui Ye等;IEEE Systems Journal;全文 *
一种面向全双工多中继协作SWIPT网络的功率消耗方案.计算机科学.2022,全文. *
最小化具有无线携能通信的全双工中继系统发射功率和;周叶宁;李陶深;曾敏;肖楠;;计算机应用(02);全文 *
直达链路下的能量采集中继选择系统的吞吐量分析;徐伟;赵睿;杨裕琳;王培臣;;信号处理(03);全文 *

Also Published As

Publication number Publication date
CN114884550A (en) 2022-08-09

Similar Documents

Publication Publication Date Title
Wang et al. Relay selection in full-duplex energy-harvesting two-way relay networks
CN108811025B (en) Wireless energy-carrying communication cooperative transmission scheme based on relay energy storage
Chen et al. Wireless-powered cooperative communications via a hybrid relay
CN107248908B (en) Hybrid duplex transmission method in cognitive relay network based on relay selection
Phan et al. Joint power allocation and relay selection in cooperative networks
CN114884550B (en) Relay cooperative transmission method for bidirectional transmission FD multi-relay cooperative SWIPT network
Di et al. Simultaneous wireless information and power transfer in two-hop OFDM decode-and-forward relay networks
KR102209990B1 (en) Multi-hop relay wireless communication system and method
CN110808769B (en) Wireless energy-carrying communication method based on OFDM (orthogonal frequency division multiplexing) amplification forwarding cooperative relay
CN113490238B (en) Relay selection optimization method for FD multi-relay cooperative SWIPT network
CN111836337A (en) Relay selection method adopting MRC and suitable for SWIPT HDAF protocol
Wang et al. Full-duplex energy-harvesting relay networks: Capacity-maximizing relay selection
Cui et al. Cross-layer optimization of sensor networks based on cooperative MIMO techniques with rate adaptation
Fan et al. Subcarrier allocation for OFDMA relay networks with proportional fair constraint
Zhang et al. End-to-end resource allocation in OFDM based linear multi-hop networks
CN111787545B (en) Full-duplex cognitive relay power distribution method based on energy collection
Wang et al. Optimum power distribution for uplink channel in a cooperative wireless CDMA network
Andrawes et al. Energy Harvesting with Link Adaptation under Different Wireless Relaying Schemes.
Aredath et al. Optimal power allocation for maximizing the energy efficiency of NOMA enabled full-duplex coordinated direct and relay transmission (CDRT) system with SWIPT
CN110830407B (en) Wireless energy-carrying communication method based on OFDM decoding and forwarding cooperative relay system
Riihonen et al. On the feasibility of full-duplex relaying powered by wireless energy transfer
Li et al. Collaborative D2D communication in relay networks with energy harvesting
CN111629417A (en) Transmission method suitable for SWIPT HDAF relay system to maximize energy transfer efficiency
Wu et al. A novel relay selection scheme with simplified power allocation for wireless relay networks
CN109219026B (en) D2D transmission method based on energy capture and interference cancellation in uplink relay network

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination
GR01 Patent grant
GR01 Patent grant