CN111246437B - D2D relay time slot number selection method - Google Patents

D2D relay time slot number selection method Download PDF

Info

Publication number
CN111246437B
CN111246437B CN202010021520.6A CN202010021520A CN111246437B CN 111246437 B CN111246437 B CN 111246437B CN 202010021520 A CN202010021520 A CN 202010021520A CN 111246437 B CN111246437 B CN 111246437B
Authority
CN
China
Prior art keywords
dre
transmission
success rate
energy consumption
relay
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
CN202010021520.6A
Other languages
Chinese (zh)
Other versions
CN111246437A (en
Inventor
裴二荣
易鑫
刘珊
鹿逊
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.)
Chongqing University of Post and Telecommunications
Original Assignee
Chongqing University of Post 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 Chongqing University of Post and Telecommunications filed Critical Chongqing University of Post and Telecommunications
Priority to CN202010021520.6A priority Critical patent/CN111246437B/en
Publication of CN111246437A publication Critical patent/CN111246437A/en
Application granted granted Critical
Publication of CN111246437B publication Critical patent/CN111246437B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W4/00—Services specially adapted for wireless communication networks; Facilities therefor
    • H04W4/70—Services for machine-to-machine communication [M2M] or machine type communication [MTC]
    • 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
    • H04W24/00—Supervisory, monitoring or testing arrangements
    • H04W24/06—Testing, supervising or monitoring using simulated traffic
    • 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]
    • H04W28/26—Resource reservation
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W40/00—Communication routing or communication path finding
    • H04W40/02—Communication route or path selection, e.g. power-based or shortest path routing
    • H04W40/22—Communication route or path selection, e.g. power-based or shortest path routing using selective relaying for reaching a BTS [Base Transceiver Station] or an access point

Abstract

The invention relates to a D2D relay time slot number selection method, and belongs to the field of narrowband Internet of things. The invention comprises the following steps: s1: setting the number of reserved time slots of DRE to be NtsSorting the candidate relays, and taking the UE with the maximum relay intention as an actual DRE; s2: calculating to obtain a working time table of the DRE; s3: establishing a transmission success rate model of the DRE; s4: establishing an energy consumption model of the DRE; s5: constructing utility function f (N)ts) And obtain an optimization problem Maxf (N)ts) (ii) a S6: find f (N)ts) Maximized NtsThe value is obtained. The method can find the N of the maximized utility function value under different delta values according to different preference requirements of userstsAnd obtaining the optimal compromise between energy consumption and transmission success rate.

Description

D2D relay time slot number selection method
Technical Field
The invention belongs to the field of narrowband Internet of things, and relates to a D2D relay time slot number selection method.
Background
The narrow-band Internet of things is a new LPWAN technology, and is very suitable for the application of the Internet of things for transmitting a small amount of information in a far range. Since most User Equipment (UE) in NB-IoT is battery powered and deployed in large scale, the cost of replacing batteries is high. Therefore, it is important to keep energy consumption at a minimum level. To address this issue, researchers have proposed using D2D communication for assisting NB-IoT systems' data transmission. In the D2D-assisted NB-IoT system, the energy saving feature of D2D short-range communication perfectly compensates for the energy shortage caused by the battery-driven NB-IoT devices.
In D2D assisted NB-IoT, D2D Relay/receiving devices (D2D Relay/Receiver Equipment, DRE) need to reserve slots for D2D communication and data forwarding. In the most ideal case, at least two slots should be reserved, one for D2D communication and one for relaying forwarding data to the Base Station (BS). However, in practice, there may be transmission failures in both the D2D communication and the relay forwarding phases, resulting in retransmissions. To improve transmission success rates, DRE needs to reserve more time slots for D2D communication and relay forwarding so that more retransmissions can be allowed. However, too many retransmissions (especially in case of poor channel quality) will significantly increase the energy consumption of the UE, and thus reduce the lifetime of the UE. Therefore, the D2D data transmission algorithm is one of the important research issues in NB-IoT systems.
The existing data transmission algorithm based on D2D communication in NB-IoT does not consider the configuration problem of DRE optimal communication time slot number. The number of reserved slots needs to be determined for the DRE, so that on one hand, the transmission success rate can be improved as much as possible, and on the other hand, the energy consumption can be controlled to a tolerable level as much as possible. Therefore, it is of practical significance to design a relay timeslot number selection method based on D2D communication in NB-IoT.
Disclosure of Invention
In view of this, the present invention provides a relay timeslot number selection method based on D2D communication in NB-IoT, which determines an optimal communication timeslot number for DRE to balance transmission success rate and energy consumption.
In order to achieve the purpose, the invention provides the following technical scheme:
a D2D relay time slot number selection method comprises the following steps:
s1: setting the number of reserved time slots of DRE to be NtsSorting the candidate relays, and taking the UE with the maximum relay intention as an actual DRE;
s2: calculating to obtain a working time table of the DRE;
s3: establishing a transmission success rate model of the DRE;
s4: establishing an energy consumption model of the DRE;
s5: constructing utility function f (N)ts) And obtain an optimization problem Maxf (N)ts)；
S6: find f (N)ts) Maximized NtsA value;
further, in step S1, the number of communication slots reserved by the DRE is set to Nts(ii) a By using
Figure BDA0002360971660000021
Represents a candidate relay set for NB-IoT terminal u, which is K UEs within D2D communication range near the midpoint of the path of terminal u to the BS to help terminal u upload packets to the BS. Candidate relay as a function of relay willingness
Figure BDA0002360971660000022
Sorting and ordering the devices r with the maximum relay intentionkAs the actual DRE roptIn which EkThe energy is left for the DRE and,
Figure BDA0002360971660000023
is a historical average of the transmission success rate of the DRE to the BS,
Figure BDA0002360971660000024
is the DRE to BS distance.
Further, in step S2, a (N-1) × 1 vector is used
Figure BDA0002360971660000025
Indicating the working schedule of terminal u, if candidate DRE
Figure BDA0002360971660000026
Is reserved for D2D communication, the decision variable is changed
Figure BDA0002360971660000027
Is 1, otherwise is 0.
Further, in step S3, the method is implemented
Figure BDA0002360971660000028
Is represented by having a given
Figure BDA0002360971660000029
ToThe packet transmission rate of terminal u, represents the expected packet transmission rate of terminal u to BS over two hops.
The transmission success rate of terminal u is denoted by P. Based on the average SINR, the average bit error rate of binary signal detection in additive white gaussian noise is:
Figure BDA00023609716600000210
wherein Q (-) represents a standard Gaussian error function,
Figure BDA00023609716600000211
assuming that bit errors occur independently of each other, P can be calculated for an L-bit packet by considering the probability of correctly receiving all individual bits. The SINR may vary over the packet transmission time due to the assumption of rayleigh fading. To simplify the analysis, we assume that the interference varies slowly over the transmission time of l bits, assuming that the SINR of l consecutive bits is the same. In this case, P of the L-bit packet can be expressed as:
Figure BDA00023609716600000212
wherein p isb(j) Is the bit error rate of the jth l-bit long segment of the packet. The transmission success rate containing W packets is:
Figure BDA0002360971660000031
for a given working schedule
Figure BDA0002360971660000032
EDR of terminal u is:
Figure BDA0002360971660000033
wherein the content of the first and second substances,
Figure BDA0002360971660000034
is that the packet is DRE in the ith slot
Figure BDA0002360971660000035
The probability of successful reception is specifically:
Figure BDA0002360971660000036
wherein, PtoRIs an estimate of the packet transmission rate of the link between terminal u and the DRE. Of the front type
Figure BDA0002360971660000037
Is DRE
Figure BDA0002360971660000038
The maximum packet transmission rate estimate for the link with the BS is N-i transmissions. The values are:
Figure BDA0002360971660000039
because the deadline for data transmission is Ntsτ, total transmission count cannot exceed Nts. If the D2D communication occupies i slots, the maximum transmission count of the second hop is at most NtsI times.
Further, in step S4, the method is implemented
Figure BDA00023609716600000310
Is represented by having a given
Figure BDA00023609716600000311
Represents the expected energy consumption of terminal u to transmit a packet to the BS over the two-hop link.
For a given operating schedule Δ(u)EEC (Δ) of terminal u(u)) Comprises the following steps:
Figure BDA00023609716600000312
wherein the content of the first and second substances,
Figure BDA00023609716600000313
is that
Figure BDA00023609716600000314
Expected energy consumption for packet transmission to BS, and at most N for transmissiontsI times, i.e
Figure BDA00023609716600000315
Wherein the content of the first and second substances,
Figure BDA00023609716600000316
and
Figure BDA00023609716600000317
is the energy consumption of the first and second hops calculated from the energy consumption model.
Figure BDA00023609716600000318
The energy consumption generated by the transmission failure of the first i-1 time slots and the transmission success in the time slot i.
Figure BDA00023609716600000319
The energy consumed for the first transmission, the first 1 unsuccessful transmission, the first successful transmission. The method comprises the following specific steps:
Figure BDA00023609716600000320
Figure BDA00023609716600000321
wherein the content of the first and second substances,
Figure BDA0002360971660000041
the transmission power of cellular UE and D2D UE, respectively.
Further, in step S5, in order to obtain an optimal compromise between energy consumption and transmission success rate, a utility function is constructed:
Figure BDA0002360971660000042
wherein E and P are the desired energy consumption and transmission success rate, PminRepresents the lowest transmission success rate that NB-IoT edge UEs can accept, and EmaxRepresenting the maximum energy consumed by the NB-IoT edge UE for one data upload. From EmaxE and P/PminIt is understood that the smaller E or the larger P, the larger the value of the utility function. N is a radical oftsThe number of reserved D2D communication slots representing DRE is an integer equal to or greater than 2 since at least two slots are required to complete the first and second hop transmissions. δ is a weighting factor for energy consumption and transmission success rate. Larger values of δ tend to be more energy efficient, but result in too low a transmission success rate; smaller values of δ tend to improve transmission success rates but result in excessive power consumption. When δ is 0, the utility function indicates that the transmission success rate is maximized, but brings the maximum energy consumption at the same time; when δ is 1, it means that power consumption is minimized while a minimum transmission success rate is obtained.
Further, in step S6, considering some limiting conditions in the scene, taking this utility function as the objective function can obtain the following optimization problem:
Max f(Nts)
Figure BDA0002360971660000043
wherein, thetai,kFor decision variables, the time slot of DRE is 1 when it is reserved for D2D communication and forwarding data, otherwise it is 0. Considering that the target function is a function with a maximum value, the DRE optimum value is searched by adopting a dichotomy method, namely, the DRE optimum value is searched at different deltas according to different preference requirements of usersUnder the value, N of the maximized utility function value is foundtsAnd obtaining the optimal compromise between energy consumption and transmission success rate.
The invention has the following effective effects: in D2D-assisted NB-IoT, a single relay selection scheme is proposed, which can ensure a certain transmission success rate, and does not need waiting of other relay devices, thereby being beneficial to saving energy. If the data is transmitted in advance, the relay equipment enters the dormancy in advance, and further energy saving is facilitated. Meanwhile, the configuration problem of the optimal communication time slot number of the DRE in the D2D-assisted NB-IoT is researched, in order to obtain the optimal compromise of the transmission success rate and the energy consumption, a utility function based on the weighted transmission success rate and the weighted energy consumption is constructed, in addition, based on the utility function, an optimization problem of the DRE communication time slot configuration is constructed, and finally, the optimal N is configuredtsTo achieve the best energy consumption and almost the best transmission success rate.
Drawings
In order to make the object, technical scheme and beneficial effect of the invention better clear, the invention provides the following drawings for illustration:
FIG. 1 is a schematic flow chart of an embodiment of the present invention;
fig. 2 is a diagram of a narrow-band internet of things network model based on D2D communication;
FIG. 3 is a DRE on-time representation of an embodiment of the present invention;
fig. 4 is a schematic diagram of a network scenario according to an embodiment of the present invention.
Detailed Description
Preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings.
The invention provides a D2D relay time slot number selection method aiming at the problem of uplink data transmission in a narrowband Internet of things. In order to obtain the optimal compromise between the transmission success rate and the energy consumption, a utility function based on the weighted transmission success rate and the weighted energy consumption is constructed, and an optimization problem of DRE communication time slot configuration is constructed based on the utility function, so that the transmission success rate can be improved as much as possible, and the energy consumption can be controlled to a tolerable level as much as possible. And determining a reserved time slot number for the DRE, ensuring a certain transmission success rate, and being beneficial to saving energy without waiting of other relay equipment. And if the data is transmitted in advance, the relay equipment enters the dormancy in advance, which is favorable for further saving energy. A flowchart of a D2D relay slot number selection method based on D2D communication in NB-IoT is shown in fig. 1.
An NB-IoT network model diagram based on D2D communication is shown in fig. 2. The UE at the edge of the cell establishes a D2D link with the adjacent UE with better channel condition, namely the DRE, and then uploads the received data to the base station, and each UE uploads the data to the base station through at most two hops. Firstly, setting the number of DRE reserved time slots as NtsSorting the candidate relays according to the relay intention size, and sorting the device r with the maximum relay intentionkAs the actual DRE ropt. And obtaining the working time table of the DRE according to the candidate relay and the transmission time. And establishing a transmission success rate model of the DRE, and then establishing an energy consumption model of the DRE. And constructing a utility function according to the transmission success rate and the energy consumption model, and establishing an optimization problem. Pair DRE N by dichotomytsSearching for the optimum value to find the N that maximizes the utility function valuetsAnd obtaining the optimal compromise between energy consumption and transmission success rate.
As shown in fig. 1, a method for optimally trading energy consumption and transmission success rate based on D2D communication in NB-IoT includes the following steps:
s1: setting the number of reserved time slots of DRE to be NtsSorting the candidate relays, and taking the UE with the maximum relay intention as an actual DRE;
s2: calculating to obtain a working time table of the DRE;
s3: establishing a transmission success rate model of the DRE;
s4: establishing an energy consumption model of the DRE;
s5: constructing utility function f (N)ts) And obtain an optimization problem Maxf (N)ts)；
S6: find f (N)ts) Maximized NtsA value;
communication time of DRE reservation for obtaining candidate relay setThe number of slots is set to Nts(ii) a By using
Figure BDA0002360971660000061
Represents a candidate relay set for NB-IoT terminal u, which is K UEs within D2D communication range near the midpoint of the path of terminal u to the BS to help terminal u upload packets to the BS. Candidate relay as a function of relay willingness
Figure BDA0002360971660000062
Sorting and ordering the devices r with the maximum relay intentionkAs the actual DRE roptIn which EkThe energy is left for the DRE and,
Figure BDA0002360971660000063
is a historical average of the transmission success rate of the DRE to the BS,
Figure BDA0002360971660000064
is the DRE to BS distance.
Using a (N-1) x 1 vector
Figure BDA0002360971660000065
Indicating the working schedule of terminal u, if candidate DRE
Figure BDA0002360971660000066
Is reserved for D2D communication, the decision variable is changed
Figure BDA0002360971660000067
Is 1, otherwise is 0. The working schedule of the DRE is shown in figure 3.
According to the working schedule of the terminal u
Figure BDA0002360971660000068
By using
Figure BDA0002360971660000069
Representing the packet transmission rate of terminal u, representing the expected packet transmission rate of terminal u to BS over two hops.
Using P meterIndicating the transmission success rate of terminal u. Based on the average SINR, the average bit error rate of binary signal detection in additive white gaussian noise is:
Figure BDA00023609716600000610
wherein Q (-) represents a standard Gaussian error function,
Figure BDA00023609716600000611
assuming that bit errors occur independently of each other, P can be calculated for an L-bit packet by considering the probability of correctly receiving all individual bits. The SINR may vary over the packet transmission time due to the assumption of rayleigh fading. To simplify the analysis, we assume that the interference varies slowly over the transmission time of l bits, assuming that the SINR of l consecutive bits is the same. In this case, P of the L-bit packet can be expressed as:
Figure BDA00023609716600000612
wherein p isb(j) Is the bit error rate of the jth l-bit long segment of the packet. The transmission success rate containing W packets is:
Figure BDA0002360971660000071
for a given working schedule
Figure BDA0002360971660000072
EDR of terminal u is:
Figure BDA0002360971660000073
wherein the content of the first and second substances,
Figure BDA0002360971660000074
is grouped in the ith time slotIs DRE
Figure BDA0002360971660000075
The probability of successful reception is specifically:
Figure BDA0002360971660000076
wherein, PtoRIs an estimate of the packet transmission rate of the link between terminal u and the DRE. Of the front type
Figure BDA0002360971660000077
Is DRE
Figure BDA0002360971660000078
The maximum packet transmission rate estimate for the link with the BS is N-i transmissions. The values are:
Figure BDA0002360971660000079
because the deadline for data transmission is Ntsτ, total transmission count cannot exceed Nts. If the D2D communication occupies i slots, the maximum transmission count of the second hop is at most NtsI times. A schematic diagram of a network scenario based on D2D communication in NB-IoT is shown in fig. 4.
According to the working schedule of the terminal u
Figure BDA00023609716600000710
By using
Figure BDA00023609716600000711
Is represented by having a given
Figure BDA00023609716600000712
Represents the expected energy consumption of terminal u to transmit a packet to the BS over the two-hop link.
For a given operating schedule Δ(u)EEC (Δ) of terminal u(u)) Comprises the following steps:
Figure BDA00023609716600000713
wherein the content of the first and second substances,
Figure BDA00023609716600000714
is DRE
Figure BDA00023609716600000715
Expected energy consumption for packet transmission to BS, and at most N for transmissiontsI times, i.e
Figure BDA00023609716600000716
Wherein the content of the first and second substances,
Figure BDA00023609716600000717
and
Figure BDA00023609716600000718
is the energy consumption of the first and second hops calculated from the energy consumption model.
Figure BDA00023609716600000719
The energy consumption generated by the transmission failure of the first i-1 time slots and the transmission success in the time slot i.
Figure BDA00023609716600000720
The energy consumed for the first transmission, the first 1 unsuccessful transmission, the first successful transmission. The method comprises the following specific steps:
Figure BDA0002360971660000081
Figure BDA0002360971660000082
wherein the content of the first and second substances,
Figure BDA0002360971660000083
the transmission power of cellular UE and D2D UE, respectively.
In order to obtain the optimal compromise between energy consumption and transmission success rate, a utility function is constructed:
Figure BDA0002360971660000084
wherein E and P are the desired energy consumption and transmission success rate, PminRepresents the lowest transmission success rate that NB-IoT edge UEs can accept, and EmaxRepresenting the maximum energy consumed by the NB-IoT edge UE for one data upload. From EmaxE and P/PminIt is understood that the smaller E or the larger P, the larger the value of the utility function. N is a radical oftsThe number of reserved D2D communication slots representing DRE is an integer equal to or greater than 2 since at least two slots are required to complete the first and second hop transmissions. δ is a weighting factor for energy consumption and transmission success rate. Larger values of δ tend to be more energy efficient, but result in too low a transmission success rate; smaller values of δ tend to improve transmission success rates but result in excessive power consumption. When δ is 0, the utility function indicates that the transmission success rate is maximized, but brings the maximum energy consumption at the same time; when δ is 1, it means that power consumption is minimized while a minimum transmission success rate is obtained.
Considering some defined conditions in the scene, taking this utility function as an objective function can result in the following optimization problem:
Max f(Nts)
Figure BDA0002360971660000085
wherein, thetai,kFor decision variables, the time slot of DRE is 1 when it is reserved for D2D communication and forwarding data, otherwise it is 0. Considering that the target function is a function with a maximum value, the DRE optimum value is searched by adopting a dichotomy method, namely according to different preference requirements of users, the DRE optimum value is searchedUnder the same value of delta, finding N of the maximized utility function valuetsAnd obtaining the optimal compromise between energy consumption and transmission success rate.
Finally, it is noted that the above-mentioned preferred embodiments illustrate rather than limit the invention, and that, although the invention has been described in detail with reference to the above-mentioned preferred embodiments, it will be understood by those skilled in the art that various changes in form and detail may be made therein without departing from the scope of the invention as defined by the appended claims.

Claims (4)

1. A D2D relay time slot number selection method is characterized in that: the method comprises the following steps:
s1: setting the number of reserved time slots of a D2D relay/receiving device (D2D relay/receiver equipment, DRE) to be NtsSorting the candidate relays, and taking the UE with the maximum relay intention as an actual DRE;
s2: calculating to obtain a working time table of the DRE;
s3: and establishing a transmission success rate model of the DRE. By using
Figure FDA0003544971040000011
Is represented by having a given
Figure FDA0003544971040000012
Represents the expected packet transmission rate of terminal u to BS over two hops. The average bit error rate of binary signal detection in additive white gaussian noise is:
Figure FDA0003544971040000013
wherein Q (-) represents a standard Gaussian error function,
Figure FDA0003544971040000014
SINR is the average signal to interference plus noise ratio. Assuming that bit errors occur independently of each other, for an L-bit packet, the transmission success rate P of the terminal u can be calculated by considering the probability of correctly receiving all individual bits. Hypothesis interferenceSlowly changes during the transmission time of l bits, so that the SINR of l consecutive bits is the same. In this case, the successful transmission rate P of the l-bit packet can be expressed as:
Figure FDA0003544971040000015
wherein p isb(j) Is the bit error rate of the jth l-bit long segment of the packet. The transmission success rate containing W packets is:
Figure FDA0003544971040000016
for a given working schedule
Figure FDA0003544971040000017
The expected packet transmission rate EDR over two hops from terminal u to BS is:
Figure FDA0003544971040000018
wherein the content of the first and second substances,
Figure FDA0003544971040000019
is that the packet is DRE in the ith slot
Figure FDA00035449710400000110
The probability of successful reception is specifically:
Figure FDA00035449710400000111
wherein, PtoRIs an estimate of the packet transmission rate of the link between terminal u and DRE,
Figure FDA00035449710400000112
is a decision variable. Of the front type
Figure FDA00035449710400000113
Is that
Figure FDA00035449710400000114
Estimation of packet transmission rate of link with BSThe maximum N-i transmissions are evaluated as:
Figure FDA00035449710400000115
wherein P istoBSIs the historical average of the transmission success rate of the DRE to the base station. Because the deadline for data transmission is Ntsτ, total transmission count cannot exceed Nts. If the D2D communication occupies i slots, the maximum transmission count of the second hop is at most NtsI times.
S4: and establishing an energy consumption model of the DRE. By using
Figure FDA00035449710400000116
Is represented by having a given
Figure FDA00035449710400000117
Represents the expected energy consumption of terminal u to transmit a packet to the BS over the two-hop link. For a given operating schedule Δ(u)EEC (Δ) of terminal u(u)) Comprises the following steps:
Figure FDA0003544971040000021
wherein the content of the first and second substances,
Figure FDA0003544971040000022
is that
Figure FDA0003544971040000023
Expected energy consumption for packet transmission to BS, and at most N for transmissiontsI times, i.e
Figure FDA0003544971040000024
Wherein, PtoBSExpressed as a historical average of the transmission success rate of the DRE to the base station,
Figure FDA0003544971040000025
and
Figure FDA0003544971040000026
is the energy consumption of the first and second hops calculated from the energy consumption model.
Figure FDA0003544971040000027
The energy consumption generated by the transmission failure of the first i-1 time slots and the transmission success in the time slot i.
Figure FDA0003544971040000028
The energy consumed for the first transmission, the first 1 unsuccessful transmission, the first successful transmission. The method comprises the following specific steps:
Figure FDA0003544971040000029
wherein the content of the first and second substances,
Figure FDA00035449710400000210
transmission power, E, for cellular UE and D2D UE, respectivelyelecIs the energy consumed to transmit or receive each bit of information, and τ is the length of one slot.
S5: constructing utility function f (N)ts) And obtain an optimization problem Maxf (N)ts). In order to obtain the optimal compromise between energy consumption and transmission success rate, a utility function is constructed:
Figure FDA00035449710400000211
wherein E and P are the desired energy consumption and transmission success rate, PminRepresents the lowest transmission success rate that NB-IoT edge UEs can accept, and EmaxRepresenting the maximum energy consumed by the NB-IoT edge UE for one data upload. From EmaxE and P/PminIt is understood that the smaller E or the larger P, the larger the value of the utility function. N is a radical oftsThe number of reserved D2D communication slots representing DRE is an integer equal to or greater than 2 since at least two slots are required to complete the first and second hop transmissions. δ is a weighting factor for energy consumption and transmission success rate. Larger values of δ tend to be more energy efficient, but result in too low a transmission success rate; smaller delta values tend to improve transmission success rates, but result in excessive power consumption. When δ is 0, the utility function indicates that the transmission success rate is maximized, but brings the maximum energy consumption at the same time; when δ is 1, it means that power consumption is minimized while a minimum transmission success rate is obtained.
S6: find f (N)ts) Maximized NtsThe value is obtained.
2. The method of claim 1, wherein the method for selecting the number of relay slots of D2D comprises: in step S1, the number of communication slots reserved by the DRE is set to Nts(ii) a By using
Figure FDA00035449710400000212
Represents a candidate relay set for NB-IoT terminal u, which is K UEs within D2D communication range near the midpoint of the path of terminal u to the BS to help terminal u upload packets to the BS. Candidate relay as a function of relay willingness
Figure FDA00035449710400000213
Sorting and ordering the devices r with the maximum relay intentionkAs actual DREroptIn which EkThe energy is left for the DRE and,
Figure FDA0003544971040000031
is a historical average of the transmission success rate of the DRE to the BS,
Figure FDA0003544971040000032
is the DRE to BS distance.
3. The method of claim 1, wherein the method for selecting the number of relay slots of D2D comprises: in step S2, a (N-1) x 1 vector is used
Figure FDA0003544971040000033
Indicating the working schedule of terminal u, if candidate DRE
Figure FDA0003544971040000034
Is reserved for D2D communication, the decision variable is changed
Figure FDA0003544971040000035
Is 1, otherwise is 0.
4. The method of claim 1, wherein the method for selecting the number of relay slots of D2D comprises: in step S6, considering some limiting conditions in the scene, taking this utility function as the objective function can get the following optimization problem:
Max f(Nts)
Figure FDA0003544971040000036
wherein, thetai,kFor decision variables, the time slot of DRE is 1 when it is reserved for D2D communication and forwarding data, otherwise it is 0. Considering that the target function is a function with a maximum value, the binary method is adopted to search the DRE optimum value, namely N of the maximized utility function value is found under different delta values according to different preference requirements of userstsAnd obtaining the optimal compromise between energy consumption and transmission success rate.
CN202010021520.6A 2020-01-09 2020-01-09 D2D relay time slot number selection method Active CN111246437B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202010021520.6A CN111246437B (en) 2020-01-09 2020-01-09 D2D relay time slot number selection method

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202010021520.6A CN111246437B (en) 2020-01-09 2020-01-09 D2D relay time slot number selection method

Publications (2)

Publication Number Publication Date
CN111246437A CN111246437A (en) 2020-06-05
CN111246437B true CN111246437B (en) 2022-04-22

Family

ID=70878124

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202010021520.6A Active CN111246437B (en) 2020-01-09 2020-01-09 D2D relay time slot number selection method

Country Status (1)

Country Link
CN (1) CN111246437B (en)

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2016188313A1 (en) * 2015-05-22 2016-12-01 Huawei Technologies Co., Ltd. Method and system for transmitting data among peer stations in decentralized manner with high channel efficiency
CN106304111A (en) * 2016-08-12 2017-01-04 梁广俊 Isomery cellular network power allocation method based on energy acquisition relay station
CN109982300A (en) * 2019-03-28 2019-07-05 重庆邮电大学 The method of user equipment uplink minimum energy consumption based on D2D communication in NB-IoT

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2016188313A1 (en) * 2015-05-22 2016-12-01 Huawei Technologies Co., Ltd. Method and system for transmitting data among peer stations in decentralized manner with high channel efficiency
CN106304111A (en) * 2016-08-12 2017-01-04 梁广俊 Isomery cellular network power allocation method based on energy acquisition relay station
CN109982300A (en) * 2019-03-28 2019-07-05 重庆邮电大学 The method of user equipment uplink minimum energy consumption based on D2D communication in NB-IoT

Non-Patent Citations (3)

* Cited by examiner, † Cited by third party
Title
Joint Energy-Aware and Buffer-Assisted Relay Selection Method for Relay-Aided D2D Communications;Lei Yu;《 2017 3rd IEEE International Conference on Computer and Communications (ICCC)》;20180326;全文 *
基于D2D与能量收集的认知中继网络资源分配研究;钮金鑫;《中国优秀博士论文全文数据库》;20180115;全文 *
基于时隙调度的D2D通信资源分配算法;滑维鑫;《陕西省通信学会2016年学术年会论文集》;20161122;全文 *

Also Published As

Publication number Publication date
CN111246437A (en) 2020-06-05

Similar Documents

Publication Publication Date Title
US10419533B2 (en) Edge server selection for device-specific network topologies
Pursley et al. Energy-efficient transmission and routing protocols for wireless multiple-hop networks and spread-spectrum radios
US9774505B2 (en) Content delivery in wireless wide area networks
US7702280B2 (en) Mobile communication system, transmission station, reception station, relay station, communication path deciding method, and communication path deciding program
Spachos et al. Energy aware opportunistic routing in wireless sensor networks
CN104009913A (en) Broadcasting method based on distance and energy balance in mobile Ad Hoc network
US20220272149A1 (en) Content Delivery in Wireless Wide Area Networks
CN110366225B (en) Wireless energy supply multi-hop communication system node selection method
Bhat et al. Lifetime ratio improvement in relay nodes using CWSN for cooperative wireless sensor networks
CN107911150B (en) Wireless energy-carrying cooperative communication method
CN110177351B (en) Efficient data transmission method for low-duty-ratio wireless sensor network
CN111246437B (en) D2D relay time slot number selection method
Li et al. Energy aware opportunistic routing for energy harvesting wireless sensor networks
CN111106856B (en) Cooperative relay network and transmission method thereof
CN111629419B (en) Transmission method suitable for AF relay system
Femila et al. Transmission power control in mobile ad hoc network using network coding and co-operative communication
CN105554894A (en) Method for cooperatively controlling transmitting power of H2H and M2M terminals in mobile network
McChesney et al. Optimization of an adaptive link control protocol for multimedia packet radio networks
Parvaresh et al. A new routing algorithm based on 2-hop neighbourhood information scheme for total power minimisation in wireless ad hoc networks
Prajapati et al. Cross layer design with extensive virtual MIMO: FS-MUP optimization model for wireless sensor network
Okumura et al. Dependable source routing scheme for multi-hop networks based on receiver-initiated MAC protocol
CN114339933B (en) Opportunistic routing method, device and system based on energy efficiency
Haghighi Energy efficiency in ARQ-based multi-hop systems and the tradeoff with throughput
Wei et al. Energy saving dynamic relaying scheme in wireless cooperative networks using markov decision process
Zewde et al. Performance Analysis of Wireless Powered Cellular Networks with Downlink SWIPT-Invited Paper

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