CN113472403B - Power distribution method based on overlapped visual area in super-large-scale MIMO system - Google Patents

Power distribution method based on overlapped visual area in super-large-scale MIMO system Download PDF

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CN113472403B
CN113472403B CN202110748696.6A CN202110748696A CN113472403B CN 113472403 B CN113472403 B CN 113472403B CN 202110748696 A CN202110748696 A CN 202110748696A CN 113472403 B CN113472403 B CN 113472403B
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antenna
user group
representing
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CN113472403A (en
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张军
刘同顺
蔡曙
王海荣
朱洪波
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Nanjing University of Posts and Telecommunications
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    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B7/00—Radio transmission systems, i.e. using radiation field
    • H04B7/02—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas
    • H04B7/04—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas
    • H04B7/0413—MIMO systems
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B7/00—Radio transmission systems, i.e. using radiation field
    • H04B7/02—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas
    • H04B7/04—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas
    • H04B7/0413—MIMO systems
    • H04B7/0426—Power distribution
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B7/00—Radio transmission systems, i.e. using radiation field
    • H04B7/02—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas
    • H04B7/04—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas
    • H04B7/0413—MIMO systems
    • H04B7/0456—Selection of precoding matrices or codebooks, e.g. using matrices antenna weighting
    • 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

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Abstract

The invention discloses a power distribution method based on an overlapped visual area in a super-large scale MIMO system, which comprises the following steps: constructing a super-large scale MIMO downlink wireless transmission system, wherein the wireless transmission system comprises a base station of a super-large scale antenna and a plurality of single antenna user groups, each single antenna user group has a respective visual area, and the visual areas comprise overlapping areas and non-overlapping areas; the base station sends signals to all users by adopting the regularized zero forcing precoding, and calculates the total rate of all users; and calculating to obtain the optimal sending power according to the total rate. Compared with the prior art, the method and the device calculate the total rate expression of the system through the regularized zero-forcing pre-coding, and obtain the optimal sending power of the antenna in the overlapping area through the alternating iteration algorithm, so that the total transmission rate of the system can be improved to the greatest extent, and further, when the optimal sending power of the antenna in the overlapping area is zero, the energy efficiency of the system can be improved.

Description

Power distribution method based on overlapped visual area in super-large scale MIMO system
Technical Field
The invention relates to a power distribution method based on an overlapped visual area in a super-large-scale MIMO system, belonging to the technical field of wireless communication.
Background
In recent years, with the explosive increase of data transmission services and the number of users, the MIMO technology cannot meet the technical requirements of a new generation of mobile communication system. Under such circumstances, various communication technologies have been proposed and developed, and a very large-scale mimo (Multiple Input Multiple output) system is one of the emerging communication technologies.
However, the very large-scale MIMO system may cause spatial non-stationarity of the system due to its huge antenna size. This is because the distance between the base station and scatterers or users is less than the rayleigh distance, the far field propagation assumption does not hold, and users can only see a portion of the base station antenna array due to the energy-limited scattering propagation path and the oversized array. The portion of the base station antenna array that is seen by the user is called the Visibility Region (VR). Each user has its specific VR, and the locations of VRs for different users may be separate, partially overlapping, or fully overlapping, depending on the surrounding environment and the relative location of the users along the antenna array. How to perform beamforming and power allocation on overlapping VR users of users is a problem that needs to be solved urgently at present.
Disclosure of Invention
The invention aims to provide a power distribution method based on an overlapped visual area in a super-large-scale MIMO system, which effectively improves the total transmission rate and the system energy efficiency of the system and has important practical significance for the development of the super-large-scale MIMO wireless communication system.
In order to achieve the above object, the present invention provides a power allocation method based on overlapping visual areas in a very large scale MIMO system, comprising the following steps:
s1, constructing a super-large scale MIMO downlink wireless transmission system, wherein the wireless transmission system comprises a super-large scale antenna base station and a plurality of single antenna user groups, each single antenna user group has a respective visual area, and the visual areas comprise overlapping areas and non-overlapping areas;
s2, the base station sends signals to all users by adopting the regular zero forcing pre-coding, and the total rate of all users is calculated;
and S3, calculating to obtain the optimal sending power according to the total rate.
As a further improvement of the invention, the base station is defined to have N antennas, the single-antenna user group is provided with T groups, and the tth single-antenna user group has K t A single antenna user, wherein, when t is 1, the visual area of the 1 st single antenna user group is defined by N 1 Root proprietary antenna and N 12 The visible area of the Tth single-antenna user group is composed of N when T is T T Root proprietary antenna and N (T-1)T A root crossover antenna; when 1 is<t<T, the visual area of the tth single-antenna user group is N t Root proprietary antenna and N (t-1)t +N t(t+1) Root-interleaved antenna assembly, N t Number of antennas of a particular area, N (t-1)t 、N t(t+1) The number of antennas in the overlap area.
As a further improvement of the present invention, the dedicated channel of the tth single-antenna user group is modeled as:
Figure BDA0003145294450000021
modeling left overlapped channels of the t-1 th single-antenna user group and the t-1 th single-antenna user group as follows:
Figure BDA0003145294450000022
modeling a right overlapping channel of the tth single-antenna user group and the t +1 th single-antenna user group as follows:
Figure BDA0003145294450000023
wherein,
Figure BDA0003145294450000024
and
Figure BDA0003145294450000025
Figure BDA0003145294450000026
channel vectors respectively representing a dedicated channel, a left overlapping channel, and a right overlapping channel; r t,k 、R (t-1)t,k And R t(t+1),k A correlation matrix representing the transmit antennas, having respective dimensions N t ×N t 、N (t-1)t ×N (t-1)t And N t(t+1) ×N t(t+1) ；x t,k 、x (t-1)t,k And x t(t+1),k Representing the random components of the channel, subject to a mean of 0 and a variance of 0, respectively
Figure BDA0003145294450000027
And
Figure BDA0003145294450000028
complex gaussian distribution.
As a further improvement of the present invention, the S2 includes the following steps:
s21, calculating a precoding matrix of the single-antenna user group by adopting the regularized zero-forcing precoding;
s22, calculating the signal-to-dryness ratio gamma of the users in the 1 st single-antenna user group 1,k ；
S23, calculating the signal-to-dryness ratio gamma of users in the Tth single-antenna user group T,k ；
S24, calculating the signal-to-dryness ratio gamma of the users in the t single-antenna user group t,k Wherein 1 is<t<T。
As a further improvement of the present invention, said S21 includes: defining precoding matrixes of a left overlapped channel, a special channel and a right overlapped channel of the tth single-antenna user group as G respectively (t-1)t 、G t And G t(t+1) Said G is (t-1)t 、G t And G t(t+1) Are respectively of size N (t-1)t ×(K t-1 +K t )、K t ×K t And K t(t+1) ×(K t +K t+1 ) According to said regularized zero-forcing precoding, left overlap channel H (t-1)t Private channel H t And the right overlapping channel H t(t+1) Of the precoding matrix G (t-1)t 、G t And G t(t+1) Can be represented by:
Figure BDA0003145294450000031
Figure BDA0003145294450000032
Figure BDA0003145294450000033
wherein, when t is 1, G (t-1)t Absent, when T ═ T, G t(t+1) In the absence of the presence of the agent,
Figure BDA0003145294450000037
represents N i An identity matrix of dimensions; w i Representing a transition matrix; alpha is alpha i Representing a regularization parameter; xi i Representing a power scaling factor; i ═ t-1) t, t, t (t + 1);
the power scaling factor xi i The specific expression of (A) is as follows:
Figure BDA0003145294450000034
Figure BDA0003145294450000035
Figure BDA0003145294450000036
wherein, P (t-1)t 、P t And P t(t+1) Respectively, the transmission power of the corresponding antenna.
As a further improvement of the present invention, the S22 includes: the signal-to-interference-and-noise ratio of user k in the 1 st single-antenna user group is:
Figure BDA0003145294450000041
wherein σ 2 Is a noise term; s 1,k A valid signal item is represented which is,
Figure BDA0003145294450000043
the interference terms within the group are represented,
Figure BDA0003145294450000044
representing the out-of-group interference term, S 1,k 、
Figure BDA0003145294450000045
And
Figure BDA0003145294450000046
are respectively:
Figure BDA0003145294450000047
Figure BDA0003145294450000048
Figure BDA0003145294450000049
wherein, a 1,k 、b 1,k 、c 1,k 、d 1,k 、e 1,k 、f 1,k And l 1,k The specific expressions of (a) are respectively:
Figure BDA00031452944500000410
Figure BDA00031452944500000411
Figure BDA00031452944500000412
Figure BDA00031452944500000413
Figure BDA00031452944500000414
Figure BDA00031452944500000415
Figure BDA00031452944500000416
wherein,
Figure BDA00031452944500000417
as a further improvement of the present invention, said S23 includes: the signal-to-interference-and-noise ratio of user k in the tth single-antenna user group is:
Figure BDA0003145294450000042
wherein σ 2 Is the noise term, S T,k A valid signal item is represented which is,
Figure BDA00031452944500000418
the interference terms within the group are represented,
Figure BDA00031452944500000419
representing the out-of-group interference term, S T,k 、
Figure BDA00031452944500000420
And
Figure BDA00031452944500000421
are respectively:
Figure BDA00031452944500000422
Figure BDA00031452944500000423
Figure BDA00031452944500000424
wherein, a T,k 、b T,k 、c T,k 、d T,k 、e T,k 、f T，k And l T,k The specific expressions of (a) are respectively as follows:
Figure BDA0003145294450000051
Figure BDA0003145294450000052
Figure BDA0003145294450000053
Figure BDA0003145294450000054
Figure BDA0003145294450000055
Figure BDA0003145294450000056
Figure BDA0003145294450000057
wherein,
Figure BDA0003145294450000058
Figure BDA0003145294450000059
as a further improvement of the present invention, the S24 includes: the signal-to-interference-and-noise ratio of the user k in the tth single-antenna user group is as follows:
Figure BDA00031452944500000510
wherein σ 2 Is the noise term, S t,k A valid signal item is represented which is,
Figure BDA00031452944500000511
the interference terms within the group are represented,
Figure BDA00031452944500000512
representing the out-of-group interference term, S t，k 、
Figure BDA00031452944500000513
And
Figure BDA00031452944500000514
are respectively:
Figure BDA00031452944500000515
Figure BDA00031452944500000516
Figure BDA00031452944500000517
wherein, a t,k 、b t，k 、c t，k 、d t，k 、e t,k 、f t,k 、i t,k 、j t,k 、l t,k 、m t,k 、n t,k 、o t,k 、p t,k And q is t,k The specific expressions of (a) are respectively as follows:
Figure BDA0003145294450000061
Figure BDA0003145294450000062
Figure BDA0003145294450000063
Figure BDA0003145294450000064
Figure BDA0003145294450000065
Figure BDA0003145294450000066
Figure BDA0003145294450000067
Figure BDA0003145294450000068
Figure BDA0003145294450000069
Figure BDA00031452944500000610
Figure BDA00031452944500000611
Figure BDA00031452944500000612
Figure BDA00031452944500000613
Figure BDA00031452944500000614
wherein,
Figure BDA0003145294450000071
Figure BDA0003145294450000072
as a further improvement of the invention, the total rate R of all users sum The expression of (a) is:
Figure BDA0003145294450000073
Figure BDA0003145294450000074
as a further improvement of the present invention, S3 specifically is:
s31, defining a total power P sent by the base station, where the total power P is:
P 1 +P 12 +P 23 +…+P T-1 +P (T-1)T +P T when P is equal to P, then P T ＝P-P 1 -P 12 -…-P (T-1)T A 1 is to P T Total rate expression R taken into all users sum Obtaining a new total rate expression
Figure BDA0003145294450000075
S32, defining the power distribution scheme as
Figure BDA0003145294450000076
Initialization iteration times S, population scale I and optimal power distribution scheme
Figure BDA0003145294450000077
S33、
Figure BDA0003145294450000078
Subject to a uniform random distribution of 0 to 1, generating P T >Scheme 0
Figure BDA0003145294450000079
The optimal transmit power is calculated as:
Figure BDA00031452944500000710
s34, if S is equal to S +1, repeat step (33)
Figure BDA00031452944500000711
Then order
Figure BDA00031452944500000712
Until S is the cutoff of the S iteration.
The invention has the beneficial effects that: the invention calculates the total rate expression of the system by the regularized zero-forcing pre-coding, obtains the optimal transmitting power of the antenna in the overlapping area by the alternating iteration algorithm, and ensures that the total transmission rate of the system can be improved to the greatest extent.
Drawings
FIG. 1 is a flow chart of a power allocation method based on overlapping visual areas in a very large scale MIMO system according to the present invention.
Fig. 2 is a model configuration diagram of a MIMO wireless transmission system in the present invention.
Fig. 3 is a model structure diagram of a preferred embodiment of the MIMO wireless transmission system shown in fig. 2.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention will be described in detail with reference to the accompanying drawings and specific embodiments.
Referring to fig. 1, the present invention provides a power allocation method based on overlapping visual areas in a very large-scale MIMO system, which depends on the distribution of the visual areas of users and maximizes the total transmission rate of all users in the system under the condition of satisfying the condition that the total power of the system is not changed, and specifically includes the following steps:
s1, constructing a super-large scale MIMO downlink wireless transmission system, wherein the wireless transmission system comprises a base station of a super-large scale antenna and a plurality of groups of single-antenna users, the plurality of groups of single-antenna users have respective visual areas, and the visual areas comprise overlapping areas and non-overlapping areas.
Referring to FIG. 2, a base station is defined to have N antennas, a single antenna user group is defined to have T groups, and a tth single antenna user group has K t A single antenna user, wherein when t is 1, the visible area of the 1 st single antenna user group is defined by N 1 Root proprietary antenna and N 12 The visible area of the Tth single-antenna user group is composed of N when T is T T Root proprietary antenna and N (T-1)T A root crossover antenna; when 1 is<t<T, the visual area of the tth single-antenna user group is N t Root proprietary antenna and N (t-1)t +N t(t+1) Root-interleaved antenna assembly, N t Number of antennas, N, of the exclusive area (t-1)t 、N t(t+1) Number of antennas in overlapping area, where N ij (i ≠ j) represents the number of antennas in the overlapping area of the single-antenna user group i and the single-antenna user group j.
The dedicated channel for the tth single antenna user group is modeled as:
Figure BDA0003145294450000081
wherein,
Figure BDA0003145294450000082
representing a dedicated channel, R t,k Representing the transmit antenna correlation matrix, R t,k Dimension of (A) is N t ×N t ，x t,k Representing the random component of the channel, and obeying a mean of 0 and a variance of
Figure BDA0003145294450000083
Complex gaussian distribution.
Single day of t-1The left overlapping channel modeling for the linear user group and the tth single-antenna user group is:
Figure BDA0003145294450000084
wherein,
Figure BDA0003145294450000085
a channel vector, R, representing the left overlapping channel (t-1)t，k Representing the transmit antenna correlation matrix, R (t-1)t，k Dimension of (A) is N (t-1)t ×N (t-1)t ，x (t-1)t，k Represents the random component of the channel and obeys a mean of 0 and a variance of
Figure BDA0003145294450000093
Complex gaussian distribution.
The right overlapping channel of the tth single-antenna user group and the t +1 th single-antenna user group is modeled as:
Figure BDA0003145294450000094
wherein,
Figure BDA0003145294450000095
a channel vector, R, representing the left overlapping channel t(t+1)，k Representing the transmit antenna correlation matrix, R t(t+1)，k Dimension of (A) is N t(t+1) ×N t(t+1) ，x t(t+1)，k Represents the random component of the channel and obeys a mean of 0 and a variance of
Figure BDA0003145294450000096
Complex gaussian distribution.
In addition to this, the present invention is,
Figure BDA0003145294450000097
represents the square root operation of the matrix, (g) H Denotes the conjugate transpose operation of a matrix, where g denotes x in the preceding formula t，k 、R t，k 、x (t-1)t，k 、R (t-1)t，k 、x t(t+1)，k Or R t(t+1)，k Of course, in other embodiments, the mathematics referred to for gThe formula or symbol is not limited as long as the formula is satisfied in the form of
Figure BDA0003145294450000098
Or (g) H And (4) finishing.
S2, the base station sends signals to all users by using the regular zero-forcing precoding, and calculates the total rate of all users, specifically:
and S21, calculating precoding matrixes of all users by adopting the regularized zero-forcing precoding.
Defining precoding matrixes of a left overlapped channel, a special channel and a right overlapped channel of the tth single-antenna user group as G respectively (t-1)t 、G t And G t(t+1) And G is (t-1)t 、G t And G t(t+1) Respectively is of size N (t-1)t ×(K t-1 +K t )、N t ×K t And N t(t+1) ×(K t +K t+1 ) Wherein, when t is 1, G (t-1)t An item is not present; when T is T, G t(t+1) An item is not present.
Left overlap channel H according to regularized zero-forcing precoding (t-1)t Private channel H t And the right overlapping channel H t(t+1) Of the precoding matrix G (t-1)t 、G t And G t(t+1) Can be represented by:
Figure BDA0003145294450000091
Figure BDA0003145294450000092
Figure BDA0003145294450000101
wherein,
Figure BDA0003145294450000106
represents N i An identity matrix of dimensions; w i Representing a transition matrix; alpha is alpha i Representing a regularization parameter; xi shape i Represents a power scaling factor, where i ═ t-1) t, t, t (t + 1);
power scaling factor xi i The specific expression of (A) is as follows:
Figure BDA0003145294450000102
Figure BDA0003145294450000103
Figure BDA0003145294450000104
wherein, P (t-1)t 、P t And P t(t+1) Respectively, the transmission power of the corresponding antenna.
S22, calculating the signal-to-dryness ratio gamma of the user k in the 1 st single-antenna user group 1,k 。
The signal-to-noise-and-interference ratio for user k in the 1 st single-antenna user group is:
Figure BDA0003145294450000105
wherein σ 2 Is the noise term, S 1,k A valid signal item is represented which is,
Figure BDA0003145294450000107
the interference terms within the group are represented,
Figure BDA0003145294450000108
representing the out-of-group interference term, S 1,k 、
Figure BDA0003145294450000109
And
Figure BDA00031452944500001010
are respectively:
Figure BDA00031452944500001011
Figure BDA00031452944500001012
Figure BDA00031452944500001013
wherein, a 1,k 、b 1,k 、c 1,k 、d 1,k 、e 1，k 、f 1,k And l 1,k The specific expressions of (a) are respectively:
Figure BDA00031452944500001014
Figure BDA00031452944500001015
Figure BDA00031452944500001016
Figure BDA00031452944500001017
Figure BDA00031452944500001018
Figure BDA00031452944500001019
Figure BDA00031452944500001020
wherein,
Figure BDA00031452944500001110
(g) [k] in order to remove the new matrix formed by the k-th row of the original matrix, g is referred to as H in the formula, however, in other embodiments, the formula referred to by g is not limited as long as the formula is satisfied and has the form of (g) [k] And (4) finishing.
S23, calculating the signal-to-dryness ratio gamma of the user k in the Tth single-antenna user group T,k
The signal-to-noise-and-interference ratio of user k in the tth single-antenna user group is:
Figure BDA00031452944500001111
wherein σ 2 Is the noise term, S T,k A valid signal item is represented which is,
Figure BDA00031452944500001112
the interference terms within the group are represented,
Figure BDA00031452944500001113
representing the out-of-group interference term, S T,k 、
Figure BDA00031452944500001114
And
Figure BDA00031452944500001115
are respectively:
Figure BDA00031452944500001116
Figure BDA00031452944500001117
Figure BDA00031452944500001118
wherein, a T,k 、b T,k 、c T,k 、d T,k 、e T,k 、f T,k And l T,k The specific expressions of (a) are respectively as follows:
Figure BDA0003145294450000111
Figure BDA0003145294450000112
Figure BDA0003145294450000113
Figure BDA0003145294450000114
Figure BDA0003145294450000115
Figure BDA0003145294450000116
Figure BDA0003145294450000117
wherein,
Figure BDA0003145294450000118
Figure BDA0003145294450000119
s24, calculating the signal-to-dryness ratio gamma of the user k in the tth single-antenna user group t,k 。
The signal-to-noise-and-interference ratio of user k in the tth single-antenna user group is:
Figure BDA0003145294450000121
wherein σ 2 Is a noise term; s t,k A valid signal item is represented which is,
Figure BDA00031452944500001211
the interference terms within the group are represented,
Figure BDA00031452944500001212
representing the out-of-group interference term, S t,k 、
Figure BDA00031452944500001213
And
Figure BDA00031452944500001214
are respectively:
Figure BDA00031452944500001215
Figure BDA00031452944500001216
Figure BDA00031452944500001217
wherein, a t,k 、b t,k 、c t,k 、d t,k 、e t,k 、f t,k 、i t,k 、j t,k 、l t,k 、m t,k 、n t,k 、o t,k 、p t,k And q is t,k The specific expressions of (a) are respectively as follows:
Figure BDA0003145294450000122
Figure BDA0003145294450000123
Figure BDA0003145294450000124
Figure BDA0003145294450000125
Figure BDA0003145294450000126
Figure BDA0003145294450000127
Figure BDA0003145294450000128
Figure BDA0003145294450000129
Figure BDA00031452944500001210
Figure BDA0003145294450000131
Figure BDA0003145294450000132
Figure BDA0003145294450000133
Figure BDA0003145294450000134
Figure BDA0003145294450000135
wherein,
Figure BDA0003145294450000136
Figure BDA0003145294450000137
total rate R for all users sum The expression of (a) is:
Figure BDA0003145294450000138
Figure BDA0003145294450000139
and S3, calculating to obtain the optimal transmission power according to the total rate of all users.
S31, defining the total transmission power of the base station as P, the transmission power satisfies P 1 +P 12 +P 23 +…+P T-1 +P (T-1)T +P T When P is equal to P, then P T ＝P-P 1 -P 12 -…-P (T-1)T A 1 is to P T Substitution into R sum Expression to obtain new total rate expression
Figure BDA00031452944500001310
S32, defining the power distribution scheme as
Figure BDA00031452944500001311
Optimal power allocation scheme
Figure BDA00031452944500001312
The number of initialization iterations is S, and the population size is I.
S33, scheme
Figure BDA00031452944500001313
Subject to a uniform random distribution of 0 to 1, generating such that P T >Scheme 0
Figure BDA00031452944500001314
The optimal transmit power is calculated as:
Figure BDA00031452944500001315
s34, repeating step (33) if S is equal to S +1
Figure BDA00031452944500001316
Then order
Figure BDA00031452944500001317
Until S is cut off for S iteration.
For convenience of understanding, the following is a preferred embodiment of the invention:
s1, constructing a super-large scale MIMO downlink wireless transmission system, wherein the wireless transmission system comprises a super-large scale antenna base station and a single antenna user, the single antenna user has a visual area, and the visual area comprises an overlapping area and a non-overlapping area.
In this embodiment, the users with single antennas are divided into two groups, and the users with two groups of single antennas have an overlapping region and a non-overlapping region, but of course, in other embodiments, the users with single antennas may be divided into S groups (S ≧ 2), as long as the purpose of having the overlapping region and the non-overlapping region for the users with single antennas in S groups can be achieved.
Referring to fig. 3, in the preferred embodiment of the present invention, K single-antenna users are defined and divided into two groups, i.e. a user group a and a user group B, wherein,in group A there is K 1 Each user, B user group has K 2 And (4) users. The base station of the super-large scale antenna comprises N antennas, wherein N are provided 2 The root antenna is in the overlapping area of the A user group and the B user group, and the visual area of the A user group has N 1 +N 2 The visible area of the antenna and the B user group is N 2 +N 3 Root antenna, here, note N 1 +N 2 +N 3 ＝N，K 1 +K 2 ＝K。
The super-large scale MIMO downlink wireless transmission system comprises three channels, wherein N is 1 Channel H between root antenna and A user group 1 、N 3 Channel H between root antenna and B user group 3 And N 2 Channel H between root antenna and A and B group users 2 The three channels are modeled as:
Figure BDA0003145294450000141
Figure BDA0003145294450000142
wherein,
Figure BDA0003145294450000143
representing respective channel vectors, H 1 Is K 1 ×N 1 Matrix of (H) 2 Is KxN 2 Matrix of H 3 Is K 2 ×N 3 The matrix of (a) is a matrix of (b),
Figure BDA0003145294450000144
Figure BDA0003145294450000145
T i,k where i is 1,2,3 denotes a transmit antenna correlation matrix, T i,k The dimensions of i ═ 1,2 and 3 are N 1 ×N 1 ,N 2 ×N 2 ,N 3 ×N 3 ；x i,k Where i is 1,2,3 denotes the random component of the channel and obeys a mean of 0 and a variance of 0, respectively
Figure BDA0003145294450000146
And
Figure BDA0003145294450000147
complex gaussian distribution of (a);
Figure BDA0003145294450000148
represents the square root operation of the matrix, (g) H Representing the conjugate transpose operation of a matrix, where g can represent any mathematical symbol or formula, provided that the form of the formula is satisfied
Figure BDA0003145294450000149
Or (g) H And (4) finishing.
And S2, the base station sends signals to all users by adopting the regular zero forcing precoding, and the total rate of all users is calculated.
And S21, calculating a precoding matrix by adopting the regularized zero-forcing precoding (RZF precoding).
Let G 1 、G 2 And G 3 Respectively is of size N 1 ×K 1 、N 2 X K and N 3 ×K 2 The matrix of (a) represents the precoding matrix of the three channels, respectively;
precoding according to RZF, G 1 、G 2 And G 3 Expressed as:
Figure BDA0003145294450000151
Figure BDA0003145294450000152
Figure BDA0003145294450000153
wherein,
Figure BDA0003145294450000154
represents N 1 An identity matrix of dimensions;
Figure BDA0003145294450000155
representing a transition matrix; alpha is alpha i I ═ 1,2,3 denote regularization parameters; xi i And i is 1,2 and 3, which represent power scaling factors, and the specific expression is as follows:
Figure BDA0003145294450000156
Figure BDA0003145294450000157
Figure BDA0003145294450000158
wherein, P 1 、P 2 And P 3 Each represents the transmission power of a three-segment antenna.
S22, calculating the signal-to-dryness ratio gamma of the user k in the user group A 1,k ；
The expression of the signal-to-dryness ratio of the user k in the user group A is as follows:
Figure BDA0003145294450000159
wherein σ 2 Is a noise term; s 1,k Represents a valid signal term;
Figure BDA00031452944500001510
representing an intra-group interference term;
Figure BDA00031452944500001511
and expressing the out-of-group interference terms, wherein the expressions are respectively as follows:
Figure BDA00031452944500001512
Figure BDA00031452944500001513
Figure BDA00031452944500001514
wherein, a 1,k 、b 1,k 、c 1,k 、d 1,k 、e 1,k 、f 1,k And l 1,k The specific expressions of (a) are respectively as follows:
Figure BDA00031452944500001515
Figure BDA0003145294450000161
Figure BDA0003145294450000162
Figure BDA0003145294450000163
Figure BDA0003145294450000164
Figure BDA0003145294450000165
Figure BDA0003145294450000166
wherein,
Figure BDA0003145294450000167
(g) [k] the new matrix formed by removing the k-th row of the original matrix, where g can represent any mathematical symbol or formula, as long as the formula is satisfied in the form of (g) [k] And (4) finishing.
S23, calculating the signal-to-dryness ratio gamma of the user k in the user group B 2,k 。
The expression of the signal-to-dryness ratio of the user k in the group B users is as follows:
Figure BDA0003145294450000168
wherein σ 2 Is the noise term, S 2,k A valid signal item is represented which is,
Figure BDA0003145294450000169
the interference terms within the group are represented,
Figure BDA00031452944500001610
and expressing the out-of-group interference terms, wherein the expressions are respectively as follows:
Figure BDA00031452944500001611
Figure BDA00031452944500001612
Figure BDA00031452944500001613
wherein, a 2,k 、b 2,k 、c 2,k 、d 2,k 、e 2,k 、f 2,k And l 2,k The specific expressions of (a) are respectively as follows:
Figure BDA00031452944500001614
Figure BDA00031452944500001615
Figure BDA00031452944500001616
Figure BDA00031452944500001617
Figure BDA00031452944500001618
Figure BDA00031452944500001619
Figure BDA0003145294450000171
the total rate of all single-antenna users in the user group A and the user group B is as follows:
Figure BDA0003145294450000172
and S3, calculating the distribution scheme of the transmission power of each part according to the total rate.
S31, defining the total transmitting power of the base station as P, and the transmitting power P of the three-segment antenna N1, N2 and N3 1 、P 2 And P 3 Satisfy P 1 +P 2 +P 3 When P is equal to
Figure BDA0003145294450000175
Wherein, P opt Representing the optimum transmit power.
Definition P 3 ＝P-P 1 -P 2 Will transmit power P 3 Power scaling factor ξ substituted in step S21 3 Medium, new power constraint factorXi Zi 3 Comprises the following steps:
Figure BDA0003145294450000173
Figure BDA0003145294450000174
apply the new power constraint factor xi 3 Total rate R for single antenna user substitution sum In the middle, a new speed expression is obtained
Figure BDA0003145294450000176
And S32, calculating a new rate obtained after each iteration.
Initialization
Figure BDA0003145294450000177
The number of initialization iterations is t, and the threshold ξ is 10 -3 。
Computing
Figure BDA0003145294450000178
And
Figure BDA0003145294450000179
rate of next new
Figure BDA00031452944500001710
A value of (1), noted as R (t-1) 。
S33, calculating
Figure BDA00031452944500001711
And
Figure BDA00031452944500001712
to obtain
Figure BDA00031452944500001713
And
Figure BDA00031452944500001714
is calculated in
Figure BDA00031452944500001715
And
Figure BDA00031452944500001716
rate of next new
Figure BDA00031452944500001717
A value of (1), noted as R (t) 。
And S34, determining the optimal transmission power distribution scheme.
When t is defined as t +1, step S32 is repeated, and | R (t) -R (t-1) When | ≦ ξ, the iteration is cut off; the optimal transmission power distribution scheme is obtained as follows:
Figure BDA00031452944500001718
Figure BDA00031452944500001719
in summary, the invention provides a power allocation method based on an overlapping visual area in a super-large-scale MIMO system, which calculates the total rate of a single-antenna user through a regularized zero-forcing pre-coding, and calculates the optimal transmitting power of an antenna in the overlapping area through an alternating iterative algorithm under the condition of meeting the requirement of unchanging the total power of the system, so that the total rate of the single-antenna user is maximized; further, when the optimal transmission power of the antenna in the overlapping area is zero, the energy efficiency of the system can be improved.
Although the present invention has been described in detail with reference to the preferred embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the spirit and scope of the present invention.

Claims (8)

1. A power distribution method based on overlapped visual areas in a super-large scale MIMO system is characterized by comprising the following steps:
s1, constructing a super-large scale MIMO downlink wireless transmission system, wherein the wireless transmission system comprises a super-large scale antenna base station and a plurality of single antenna user groups, each single antenna user group has a respective visual area, and the visual areas comprise overlapping areas and non-overlapping areas;
defining that the base station has N antennae, wherein the single-antenna user group is provided with T groups, and the tth single-antenna user group has K t A single antenna user, wherein, when t is 1, the visual area of the 1 st single antenna user group is defined by N 1 Root proprietary antenna and N 12 The visible area of the Tth single-antenna user group is composed of N when T is T T Root proprietary antenna and N (T-1)T A root crossover antenna; when 1 < T < T, the visual area of the tth single-antenna user group is defined by N t Root proprietary antenna and N (t-1)t +N t(t+1) A root crossover antenna; n is a radical of t Number of antennas, N, of the exclusive area (t-1)t 、N t(t+1) Number of antennas in an overlapping area;
the dedicated channel modeling of the tth single-antenna user group is as follows:
Figure FDA0003678510910000011
the left overlap channel modeling for the t-1 th single antenna user group and the t-th single antenna user group is:
Figure FDA0003678510910000012
modeling a right overlapping channel of the tth single-antenna user group and the t +1 th single-antenna user group as follows:
Figure FDA0003678510910000013
wherein,
Figure FDA0003678510910000014
and
Figure FDA0003678510910000015
Figure FDA0003678510910000016
channel vectors respectively representing a dedicated channel, a left overlapping channel, and a right overlapping channel; r t，k 、R (t-1)t，k And R t(t+1)，k Correlation matrix representing transmitting antennas, with dimensions N t ×N t 、N (t-1)t ×N (t-1)t And N t(t+1) ×N t(t+1) ；x t，k 、x (t-1)t，k And x t(t+1)，k Representing the random components of the channel, subject to a mean of 0 and a variance of 0, respectively
Figure FDA0003678510910000017
And
Figure FDA0003678510910000018
complex gaussian distribution of (a);
s2, the base station sends signals to all users by adopting the regular zero forcing pre-coding, and the total rate of all users is calculated;
and S3, calculating to obtain the optimal sending power according to the total rate.
2. The method for power allocation based on overlapping visual areas in very large scale MIMO system of claim 1, wherein said S2 comprises the following steps:
s21, calculating a precoding matrix of the single-antenna user group by adopting the regularized zero-forcing precoding;
s22, calculating the signal-to-dryness ratio gamma of the users in the 1 st single-antenna user group 1，k ；
S23, calculating the signal-to-dryness ratio gamma of users in the Tth single-antenna user group T，k ；
S24, calculating the signal-to-dryness ratio gamma of the users in the t single-antenna user group t，k Wherein T is more than 1 and less than T.
3. The method of claim 2, wherein the S21 packet is a packet of power allocation based on overlapping visual regions in the very large scale MIMO systemComprises the following steps: defining precoding matrixes of a left overlapped channel, a special channel and a right overlapped channel of the tth single-antenna user group as G respectively (t-1)t 、G t And G t(t+1) Said G is (t-1)t 、G t And G t(t+1) Respectively is of size N (t-1)t ×(K t-1 +K t )、N t ×K t And N t(t+1) ×(K t +K t+1 ) According to said regularized zero-forcing precoding, left overlap channel H (t-1)t Private channel H t And the right overlapping channel H t(t+1) Of the precoding matrix G (t-1)t 、G t And G t(t+1) Can be represented by:
Figure FDA0003678510910000021
Figure FDA0003678510910000022
wherein, when t is 1, G (t-1)t Absent, when T ═ T, G t(t+1) In the absence of the presence of the agent,
Figure FDA0003678510910000023
represents N i An identity matrix of dimensions; w is a group of i Representing a transition matrix; alpha is alpha i Representing a regularization parameter; xi shape i Representing a power scaling factor; i ═ t-1) t, t, t (t + 1);
the power scaling factor xi i The specific expression of (A) is as follows:
Figure FDA0003678510910000024
Figure FDA0003678510910000031
wherein, P (t-1)t 、P t And P t(t+1) Respectively, the transmission power of the corresponding antenna.
4. The method for power allocation based on overlapping visual regions in very large scale MIMO system of claim 2, wherein said S22 comprises: the signal-to-interference-and-noise ratio of user k in the 1 st single-antenna user group is:
Figure FDA0003678510910000032
wherein σ 2 Is a noise term; s 1，k A valid signal item is represented which is,
Figure FDA0003678510910000033
the interference terms within the group are represented,
Figure FDA0003678510910000034
representing the out-of-group interference term, S 1，k 、
Figure FDA0003678510910000035
And
Figure FDA0003678510910000036
are respectively:
Figure FDA0003678510910000037
Figure FDA0003678510910000038
Figure FDA0003678510910000039
wherein ξ i Representing a power scaling factor; i ═ T-1) T, T, T (T +1), T ∈ [1, T]，a 1，k 、b 1，k 、c 1，k 、d 1，k 、e 1，k 、f 1，k And l 1，k The specific expressions of (a) are respectively:
Figure FDA00036785109100000310
Figure FDA00036785109100000311
Figure FDA00036785109100000312
Figure FDA00036785109100000313
Figure FDA00036785109100000314
Figure FDA00036785109100000315
Figure FDA00036785109100000316
wherein,
Figure FDA00036785109100000317
representing the joint index of users within user group 1,
Figure FDA00036785109100000318
Figure FDA00036785109100000319
an index representing a right interfering user of user group 1; h [·] Representing a new matrix of the H matrix after removing the index column; w i Denotes a transition matrix, i ═ (T-1) T, T, T (T +1), T ∈ [1, T ∈]。
5. The method for power allocation based on overlapping visual regions in very large scale MIMO system of claim 2, wherein said S23 comprises: the signal-to-interference-and-noise ratio of user k in the tth single-antenna user group is:
Figure FDA0003678510910000041
wherein σ 2 Is the noise term, S T，k A valid signal item is represented which is,
Figure FDA0003678510910000042
the interference terms within the group are represented,
Figure FDA0003678510910000043
representing the out-of-group interference term, S T，k 、
Figure FDA0003678510910000044
And
Figure FDA0003678510910000045
are respectively:
Figure FDA0003678510910000046
Figure FDA0003678510910000047
Figure FDA0003678510910000048
wherein ξ i Represents a power scaling factor; i ═ T-1) T, T, T (T +1), T ∈ [1, T]，a T，k 、b T，k 、c T，k 、d T，k 、e T，k 、f T，k And l T，k The specific expressions of (a) are respectively as follows:
Figure FDA0003678510910000049
Figure FDA00036785109100000410
Figure FDA00036785109100000411
Figure FDA00036785109100000412
Figure FDA00036785109100000413
Figure FDA00036785109100000414
Figure FDA00036785109100000415
wherein,
Figure FDA00036785109100000416
an index representing the left interfering user of user group T,
Figure FDA00036785109100000417
a joint index representing users within a user group T; h [·] Representing a new matrix of the H matrix after removing the index column; w i Denotes a transition matrix, i ═ (T-1) T, T, T (T +1), T ∈ [1, T ∈]。
6. The method for power allocation based on overlapping visual regions in very large scale MIMO system of claim 2, wherein said S24 comprises: the signal-to-interference-and-noise ratio of the user k in the tth single-antenna user group is as follows:
Figure FDA0003678510910000051
wherein σ 2 Is the noise term, S t，k A valid signal item is represented which is,
Figure FDA0003678510910000052
the interference terms within the group are represented,
Figure FDA0003678510910000053
representing the out-of-group interference term, S t，k 、
Figure FDA0003678510910000054
And
Figure FDA0003678510910000055
are respectively:
Figure FDA0003678510910000056
Figure FDA0003678510910000057
Figure FDA0003678510910000058
wherein ξ i Representing a power scaling factor; i ═ T-1) T, T, T (T +1), T ∈ [1, T]，a t，k 、b t，k 、c t，k 、d t，k 、e t，k 、f t，k 、i t，k 、j t，k 、l t，k 、m t，k 、n t，k 、o t，k 、p t，k And q is t，k The specific expressions of (a) are respectively as follows:
Figure FDA0003678510910000059
Figure FDA00036785109100000510
Figure FDA00036785109100000511
Figure FDA00036785109100000512
Figure FDA00036785109100000513
Figure FDA00036785109100000514
Figure FDA00036785109100000515
Figure FDA0003678510910000061
Figure FDA0003678510910000062
Figure FDA0003678510910000063
Figure FDA0003678510910000064
Figure FDA0003678510910000066
Figure FDA0003678510910000067
Figure FDA0003678510910000068
Figure FDA0003678510910000069
wherein,
Figure FDA00036785109100000610
an index representing the left interfering user of the user group t,
Figure FDA00036785109100000611
Figure FDA00036785109100000612
a joint index representing users within the user group t,
Figure FDA00036785109100000613
Figure FDA00036785109100000614
a joint index representing the interfering users to the right of the user group t,
Figure FDA00036785109100000615
Figure FDA00036785109100000616
an index representing users within the user group t; h [·] Representing a new matrix of the H matrix after removing the index column; w i Denotes a transition matrix, i ═ T (T-1) T, T, T (T +1), T ∈ [1, T]。
7. The method of claim 2, wherein the aggregate rate R for all users is based on the power allocation for overlapping visual zones in the very large scale MIMO system sum The expression of (c) is:
Figure FDA00036785109100000617
Figure FDA00036785109100000618
8. the method for power allocation based on overlapping visual areas in a very-large-scale MIMO system of claim 7, wherein S3 specifically includes:
s31, defining a total power P sent by the base station, where the total power P is: p 1 +P 12 +P 23 +…+P T-1 +P (T-1)T +P T When P is equal to P, then P T ＝P-P 1 -P 12 -…-P (T-1)T From P to P T Total rate expression R taken into all users sum Obtaining a new total rate expression
Figure FDA0003678510910000071
S32, defining the power distribution scheme as
Figure FDA0003678510910000072
Initialization iteration times S, population scale I and optimal power distribution scheme
Figure FDA0003678510910000073
S33、
Figure FDA0003678510910000074
Subject to a uniform random distribution of 0 to 1, generating such that P T Scheme > 0
Figure FDA0003678510910000075
I belongs to I, and the optimal sending power is calculated as follows:
Figure FDA0003678510910000076
s34, repeating step (33) if S is equal to S +1
Figure FDA0003678510910000077
Then order
Figure FDA0003678510910000078
Until S is the cutoff of the S iteration.
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