CN103491620B - Based on the distributed uplink power control method of user-driven in a kind of heterogeneous network - Google Patents

Abstract

The present invention is a kind of distributed uplink power control method based on user-driven in heterogeneous network in heterogeneous network, the method be characterized in that first according to macrocell user self measure letter leakage noise ratio (SLNR) macrocell uplink user is divided into central user group and edge customer group, all Microcell users in macrocell coverage area are not grouped；Secondly, all Microcell users and macrocell central user group shared system central user frequency spectrum, macrocell edge customer group takies the special frequency spectrum of edge customer；Finally, all Microcell users and macrocell central user adopt the distributed uplink power control method of user-driven, and macrocell edge is respectively with carrying out uplink with maximum transmission power per family.The method takes full advantage of the cell coverage area and disturbed condition that in network, different user self is residing, select suitable frequency spectrum resource multiplexing scheme and power control strategy, it is ensured that while channeling, be effectively improved the overall transfer performance of all uplink user in heterogeneous network.

Description

Based on the distributed uplink power control method of user-driven in a kind of heterogeneous network

Technical field

The invention belongs to wireless communication technology field, relate to the design suppressing interference that the up middle employing power of isomery controls, mainly for macrocell user in heterogeneous network and the uplink interference problem between the user of Microcell.

Background technology

Owing to frequency spectrum resource is day by day in short supply, in order to improve the spectrum efficiency of existing system, Future broadband mobile communication system is introduced into the multiple-level hierarchical network framework that covering power is different with scope, effectively meets system flexible deployment, increases overall system capacity and improves the demand of user performance.Heterogeneous network framework refers within the scope of the macrocell covered in traditional base station, disposes the microcell base station of one or more low transmitting power according to demand, for the focus covering etc. of little scope.These microcell base stations share the special frequency range of mobile communication system with macro base station, such that it is able to improve system overall spectrum utilization rate and strengthen the user's transfer rate in microcell base station coverage.

In up heterogeneous system, owing to accessing user and access Microcell user's shared band of macro base station, therefore all can receive on any grand/micro-base station and come from the uplink interference accessing other community users.Being in a community or the user at multiple MPS process edge especially for those, therefore the uplink transmission power of its use is relatively large can cause comparatively serious presence of intercell interference.In traditional homogeneous network, system uplink power controls to be that each user requires according to own services prescription (QoS) and this user configures transmission power intensity to the large scale path loss between dominant base.If user distance dominant base is farther out, path loss is bigger, then user will improve the transmitting power of self to a certain extent, to ensure that user uplink Signal-to-Noise that base station receives is in a desired level.But, in heterogeneous network, the Microcell of some low-power, little covering owing to being likely to random distribution inside macro base station.The user that services if located in macrocell edge increases transmitting power, exists owing to there being Microcell to cover near it, and therefore the uplink user signal received in Microcell can produce significantly interference, thus the user performance affected in picocell coverage area.

Additionally, effective spectrum due to Microcell and the complete multiplexing existing system of macrocell, in heterogeneous system, co-channel interference ratio is more serious, make systematic entirety can decline comparatively fast, and existing uplink power control scheme cannot take into account user's disturbed condition to neighbor cell user, therefore, in up heterogeneous system, we need a dynamic power control scheme can taken into account neighbor cell user's disturbed condition, according to the channel fading of different user in heterogeneous system and its neighbor cell user is disturbed feature, select suitable up dynamic power control scheme, thus effectively suppressing in heterogeneous system the co-channel interference between different districts, and improve the overall performance of system.

Summary of the invention

Technical problem: it is an object of the invention to provide a kind of distributed uplink power control method based on user-driven in heterogeneous network, the method promotes to some extent in overall system capacity performance, it is possible to better improve the systematic function of macrocell.The method, delay of feedback is smaller, implements complexity low, and system easily realizes.

Technical scheme: in up heterogeneous network system, want to utilize the spectrum reuse in heterogeneous network to promote systematic entirety energy, the best way is according to different user in network self residing cell coverage area and disturbed condition, select suitable frequency spectrum resource multiplexing scheme and power control strategy, so can ensure to be effectively improved in heterogeneous network while channeling the overall transfer performance of all uplink user.The method is according to different user in network self residing cell coverage area and disturbed condition, select frequency spectrum resource multiplexing scheme and power control strategy, ensureing to be effectively improved in heterogeneous network while channeling the overall transfer performance of all uplink user, the distributed uplink power control method of this user-driven sequentially includes the following steps:

1.) macrocell user is divided into central user and edge customer；Each user k measures the letter leakage noise ratio SLNR value of oneself according to following formula:

${\mathrm{\η}}_k=\frac{\stackrel{\‾}{p}\·{\mathrm{PL}}_k}{\underset{j=1,j\≠k}{\overset{L}{\mathrm{\Σ}}}\stackrel{\‾}{p}\·{\mathrm{PL}}_k^j+{\mathrm{\σ}}^2}$

WhereinIt is the initialized transmitting power of this user, actual performance number when can use last transmission, PL_kRepresent that user is to the large scale path loss between its serving BS, andRepresent that this user path loss to other cell base station, L expression system include macro base station and microcell base station at interior total base station number, σ²Represent noise power, each user η according to oneself in macrocell_kValue and given threshold value SLNR_thCompare, if η_k≥SLNR_th, then this user is macrocell central user；Otherwise, this user is macrocell edge customer；J is base station number, including macro base station and microcell base station；

2.) whole system spectral bandwidth being divided into central user transmission band and edge customer dedicated frequency band, all Microcell users and macrocell central user group shared system central user frequency spectrum, macrocell edge customer group takies the special frequency spectrum of edge customer；

3.) for all community users, uniform distribution uses transmission band；

4.) for macrocell central user and all Microcell users, its uplink transmission power is:

$P=\min \{P_{\max },P_0^{\mathrm{adjusted}}+\mathrm{\α}\·\mathrm{PL}+10{{\log }_{10}}^M\}$

Wherein P_maxFor user allow maximum transmission power, $P_0^{\mathrm{adjusted}}=\max \{P_0^{\min },\min \{P_0^{\max },P_0+k\&CenterDot;\mathrm{SLNR}\left\}\right\}$ For believing that the value self adaptation goal-selling of leakage noise ratio receives power according to user,WithRespectively P₀Predeterminable minima and maximum, P₀Receiving power for initial target, k >=0 is an adjustmentParameter, α is path loss compensating factor (0 < α≤1), and M is allocated to the Resource Block RB number of user, and PL is the path loss that user is arrived in base station；

5.) for macrocell edge customer, user emission power is set as maximum permissible value P_max。

Beneficial effect:

(1) in the heterogeneous network that the present invention proposes, a kind of distributed uplink power control method of user-driven promotes to some extent in overall system capacity performance, and according to different policy scenes, its performance boost is about 10%～20%.

(2) for network uplink fractional rating control method (FPC) in existing communication standard, this invention is obtaining close microcell system performance meanwhile, it is capable to better improve the systematic function of macrocell.

(3) this invention is a kind of distributed uplink power control method of user-driven, and delay of feedback is smaller, implements complexity low, and system easily realizes.

Accompanying drawing explanation

Fig. 1 is that isomery up-link user disturbs schematic diagram.

Fig. 2 gives the distributed uplink power control method flow diagram of this user-driven.

Fig. 3 gives the CDF curve of all user rates during Ratio=0.1.

Fig. 4 gives the CDF curve of all user rates during Ratio=0.2.

Detailed description of the invention

The technical method of invention emulates on heterogeneous network system platform.The main emulation testing present invention provides the specific implementation method of method.It addition, in order to compare, give the result of two kinds of classical Poewr control methods.The algorithm specifically compared is:

Method (1) Pmax: all users adopt maximum power transmission；

Method (2) FPC: the ascending power control method of definition in employing standard, parameter is shown in following table；

Method (3) the inventive method: the algorithm that the present invention provides, concrete steps are identical in above summary of the invention.

The simulation parameter of this invention is as shown in table 1.Wherein, Ratio is the ratio that edge customer frequency band accounts for total frequency band.

The method is according to different user in network self residing cell coverage area and disturbed condition, select frequency spectrum resource multiplexing scheme and power control strategy, ensureing to be effectively improved in heterogeneous network while channeling the overall transfer performance of all uplink user, the distributed uplink power control method of this user-driven sequentially includes the following steps:

1.) macrocell user is divided into central user and edge customer；Each user k measures the letter leakage noise ratio SLNR value of oneself according to following formula:

${\mathrm{\&eta;}}_k=\frac{\stackrel{\&OverBar;}{p}\&CenterDot;{\mathrm{PL}}_k}{\underset{j=1,j\&NotEqual;k}{\overset{L}{\mathrm{\&Sigma;}}}\stackrel{\&OverBar;}{p}\&CenterDot;{\mathrm{PL}}_k^j+{\mathrm{\&sigma;}}^2}$

WhereinIt is the initialized transmitting power of this user, actual performance number when can use last transmission, PL_kRepresent that user is to the large scale path loss between its serving BS, andRepresent that this user path loss to other cell base station, L expression system include macro base station and microcell base station at interior total base station number, σ²Represent noise power, each user η according to oneself in macrocell_kValue and given threshold value SLNR_thCompare, if η_k≥SLNR_th, then this user is macrocell central user；Otherwise, this user is macrocell edge customer；J is base station number (including macro base station and microcell base station)；

2.) whole system spectral bandwidth being divided into central user transmission band and edge customer dedicated frequency band, all Microcell users and macrocell central user group shared system central user frequency spectrum, macrocell edge customer group takies the special frequency spectrum of edge customer；

3.) for all community users, uniform distribution uses transmission band；

4.) for macrocell central user and all Microcell users, its uplink transmission power is:

$P=\min \{P_{\max },P_0^{\mathrm{adjusted}}+\mathrm{\&alpha;}\&CenterDot;\mathrm{PL}+10{{\log }_{10}}^M\}$

Wherein P_maxFor user allow maximum transmission power, $P_0^{\mathrm{adjusted}}=\max \{P_0^{\min },\min \{P_0^{\max },P_0+k\&CenterDot;\mathrm{SLNR}\left\}\right\}$ For believing that the value self adaptation goal-selling of leakage noise ratio receives power according to user,WithRespectively P₀Predeterminable minima and maximum, P₀Receiving power for initial target, k >=0 is an adjustmentParameter, α is path loss compensating factor (0 < α≤1), M be allocated to user Resource Block (RB) number, PL is the path loss that user is arrived in base station；

5.) for macrocell edge customer, user emission power is set as maximum permissible value P_max。

Table 1 simulation parameter table

Fig. 1 gives the interference model rough schematic in heterogeneous network.Wherein, MUE1 and MUE2 and macro base station have identical distance, but MUE1 is closer from two microcell base stations；Under conventional power control (FPC), MUE1 and MUE2 launches identical power, and MUE1 is much bigger to the interference of Microcell to the interference ratio MUE2 of Microcell；Adopting the Poewr control method of the present invention, the interference of Microcell can be effectively controlled by MUE1.

Fig. 2 is the algorithm flow chart of the present invention.According to the letter leakage noise ratio (SLNR) that macrocell user self is measured, macrocell uplink user being divided into central user group and edge customer group, all Microcell users in macrocell coverage area are not grouped.All Microcell users and macrocell central user group shared system central user frequency spectrum, and adopt the distributed circule power control method of a kind of user-driven；Macrocell edge customer group takies the special frequency spectrum of edge customer and each with carrying out uplink with maximum transmission power per family.

Fig. 3 and Fig. 4 sets forth the CDF curve chart of macrocell user and Microcell user during Ratio=0.1 and 0.2.Two kinds of relatively more traditional power control schemes, when with maximum power transmission, macrocell user is relatively larger to the interference of Microcell user, and the power system capacity of Microcell is relatively small.And adopt FPC and it is proposed that Resource Allocation Formula, macrocell capacity compared to reducing to some extent in Pmax situation, but due to have employed power control make the macrocell interference reduction to Microcell, the power system capacity of Microcell promotes to some extent.All in all, it is proposed that heterogeneous network in a kind of distributed uplink power control method of user-driven promote to some extent in overall system capacity performance, according to different policy scenes, its performance boost is about 10%～20%.It addition, it is proposed that algorithm for existing FPC scheme, can better improve the systematic function of macrocell while obtaining close microcell system performance.

Corresponding with Fig. 3, below table 1Ratio=0.1

Corresponding with Fig. 4, below table 2Ratio=0.2

Claims (1)

1. based on the distributed uplink power control method of user-driven in a heterogeneous network, it is characterized in that the method is according to different user in network self residing cell coverage area and disturbed condition, select frequency spectrum resource multiplexing scheme and power control strategy, ensureing to be effectively improved in heterogeneous network while channeling the overall transfer performance of all uplink user, the distributed uplink power control method of this user-driven sequentially includes the following steps:

1.) macrocell user is divided into central user and edge customer；Each user k measures the letter leakage noise ratio SLNR value of oneself according to following formula:

${\mathrm{\&eta;}}_k=\frac{\stackrel{\&OverBar;}{p}\&CenterDot;{\mathrm{PL}}_k}{\underset{j=1,j\&NotEqual;k}{\overset{L}{\&Sigma;}}\stackrel{\&OverBar;}{p}\&CenterDot;{\mathrm{PL}}_k^j+{\mathrm{\&sigma;}}^2}$

WhereinIt is the initialized transmitting power of this user, actual performance number when can use last transmission, PL_kRepresent that user is to the large scale path loss between its serving BS, andRepresent that this user path loss to other cell base station, L expression system include macro base station and microcell base station at interior total base station number, σ²Represent noise power, each user η according to oneself in macrocell_kValue and given threshold value SLNR_thCompare, if η_k≥SLNR_th, then this user is macrocell central user；Otherwise, this user is macrocell edge customer；J is base station number, including macro base station and microcell base station；

2.) whole system spectral bandwidth being divided into central user transmission band and edge customer dedicated frequency band, all Microcell users and macrocell central user group shared system central user transmission band, macrocell edge customer group takies edge customer dedicated frequency band；

3.) for all community users, uniform distribution uses transmission band；

4.) for macrocell central user and all Microcell users, its uplink transmission power is:

$P=min\{P_{max},P_0^{adjusted}+\mathrm{\&alpha;}\&CenterDot;PL+10{{\log }_{10}}^M\}$

Wherein P_maxFor user allow maximum transmission power,

For believing that the value self adaptation goal-selling of leakage noise ratio receives power according to user,WithRespectively P₀Predeterminable minima and maximum, P₀Receiving power for initial target, a >=0 is an adjustmentParameter, α is path loss compensating factor (0 < α≤1), and M is allocated to the Resource Block RB number of user, and PL is the path loss that user is arrived in base station；

5.) for macrocell edge customer, its uplink transmission power is the maximum transmission power P that user allows_max。