WO2016045417A1

WO2016045417A1 - Method, device for determining serving base station and base station

Info

Publication number: WO2016045417A1
Application number: PCT/CN2015/081469
Authority: WO
Inventors: 程翔; 汪彬; 李红豆; 常永宇
Original assignee: 中兴通讯股份有限公司
Priority date: 2014-09-26
Filing date: 2015-06-15
Publication date: 2016-03-31
Also published as: CN105517115B; CN105517115A

Abstract

A method, device for determining a serving base station and a base station are disclosed in the present invention, wherein the method comprises: determining a centre average path loss value between the number of N base stations in a Ultra Dense Network (UDN) and a centre user, and an edge average path loss value between the number of N base stations and an edge user, and the centre user being a user in a pre-determined range served by the number of N base stations, and the edge user being a user outside the pre-determined range served by the number of N base stations; and determining a base station for serving from the number of N base stations according to the centre average path loss value and the edge average path loss value. With the present invention, the problem of excessive system interference caused by an irrational allocation of base stations in the Ultra Dense Network (UDN) in the related art is solved, and then the effect that interference between the base stations is reduced and system performance is improved is achieved.

Description

Method, device and base station determined by serving base station

Technical field

The present invention relates to the field of communications, and in particular, to a method, an apparatus, and a base station for determining a serving base station.

Background technique

In LTE R12, a Small Cell is introduced, that is, a small cell base station, which is simply referred to as a small base station. Small Cell is a low-power wireless access node that operates in an authorized, unlicensed spectrum. Small Cell can be used indoors or outdoors, covering 10 meters of indoor space or 2 km in the field; in contrast, macro base stations can cover several kilometers. Small Cell combines femtocell, picocell, microcell and distributed wireless technologies. Small Cell is characterized by dense layout and overlapping coverage.

Ultra Dense Networks (UDN), one of the 5G business development requirements, is a network architecture formed by high-density deployment of Small Cell without exact planning requirements. This network architecture can improve spectral efficiency by reducing the distance between the transmitter and the receiver, while improving the quality of service of the macro base station by offloading the wireless traffic. UDN also provides an effective solution for the high capacity and high data rate requirements of future communication systems. UDN is a model for the development of network architecture in the direction of low cost, plug and play, self-organization and self-healing.

In the UDN, the massively densely deployed Small Cell also poses some challenges for the development of 5G. For example, more complex interference situations, etc., and different levels of coordination and cooperation between Small Cell are the key to controlling interference at an appropriate level and increasing network capacity. How to reduce system interference and improve system performance need to be solved by rationally planning the location of small cells on this basis.

Aiming at the problem that the allocation of base stations in the ultra-dense network UDN in the related art is unreasonable and the system interference is too large, an effective solution has not been proposed yet.

Summary of the invention

The present invention provides a method, an apparatus, and a base station for determining a serving base station, so as to at least solve the problem that the allocation of the base station in the ultra-dense network UDN in the related art is unreasonable and the system interference is excessive.

According to an aspect of the present invention, a method for determining a serving base station includes: determining a central average path loss value between N base stations of a super-dense network UDN and a center user, and between the N base stations and edge users An edge average path loss value, wherein the central user is within a predetermined range of service for the N base stations a user outside the predetermined range that the edge user serves for the N base stations; determining, for the service, from the N base stations according to the central average path loss value and the edge average path loss value Base station.

In the embodiment of the present invention, the base station for serving is determined from the N base stations according to the central average path loss value and the edge average path loss value by using the following formula:

Wherein, OF is a parameter value of a base station for determining a service, f ₁ is the central average path loss value, and f ₂ is the edge average path loss value.

In the embodiment of the present invention, the central average path loss value is determined according to the following formula:

Where w _k =|C ^k |/K,

u denotes a penalty factor and takes a constant. For the determined serving small base station k, the relative path loss between all users and the small base station is:

Where g _j ^(k) is the path loss between the jth user and the kth base station; g _j.max represents the maximum allowable path loss, calculated by the following formula: g _j,max =(P ₀ )dBm -(N ₀ B)dBm-(F)dB-(SNR _jmin )dB, P0 represents the base station transmit power, N0 represents the noise power spectral density, B represents the channel bandwidth, F represents the receive noise figure, SNRj, min is expressed in the jth The minimum SNR threshold at the user; C ^k is the set of users served by the small base station k, |C ^k | is the total number of users served by the small base station k; C ₁ takes an integer in the range, when C ₁ When ||C ^k |, the central average path loss value is the average path loss value between all service users and the serving base station.

In the embodiment of the present invention, the edge average path loss value is determined according to the following formula:

Where w _k =|C ^k |/K,

In the embodiment of the present invention, determining the base station for serving according to the value of OF includes: turning off a base station corresponding to a minimum OF value of the OF values, and determining a base station for serving from the N base stations.

According to another aspect of the present invention, there is provided a device for determining a serving base station, comprising: a first determining module configured to determine a central average path loss value and a value between N base stations of the ultra-dense network UDN and a central user An edge average path loss value between the N base stations and the edge user, wherein the central user is a user within a predetermined range served by the N base stations, and the edge user serves the N base stations a user outside the predetermined range; a second determining module configured to determine a base station for serving from the N base stations based on the central average path loss value and the edge average path loss value.

In an embodiment of the present invention, the apparatus further includes: a first calculating module, configured to determine, according to the central average path loss value and the edge average path loss value, from the N base stations by using a formula Service base station:

In the embodiment of the present invention, the apparatus further includes: a second calculating module, configured to determine the central average path loss value according to the following formula:

Where w _k =|C ^k |/K,

In an embodiment of the present invention, the apparatus further includes: a third calculating module, configured to determine the edge average path loss value according to the following formula:

Where w _k =|C ^k |/K,

In the embodiment of the present invention, the device further includes: a third determining module, configured to determine, according to the value of the OF, the base station for serving, comprising: turning off a base station corresponding to a minimum OF value of the OF values, from the N A base station for serving is determined among the base stations.

According to another aspect of the present invention, there is also provided a base station comprising at least one of the above means.

Determining, by the embodiment of the present invention, a central average path loss value between the N base stations of the ultra-dense network UDN and a central user, and an edge average path loss value between the N base stations and an edge user, where the central user a user within a predetermined range serving the N base stations, the edge user serving the user outside the predetermined range served by the N base stations; according to the central average path loss value and the edge average path Determining the value of the base station for the service from the N base stations, solving the problem that the allocation of the base station in the ultra-dense network UDN in the related art is unreasonable and causing excessive system interference, thereby reducing interference between the base stations and improving system performance. Effect.

DRAWINGS

The drawings described herein are intended to provide a further understanding of the invention, and are intended to be a part of the invention. In the drawing:

1 is a flow chart of a method for determining a serving base station according to an embodiment of the present invention;

2 is a block diagram of an apparatus for determining a serving base station according to an embodiment of the present invention;

3 is a block diagram 1 of an apparatus for determining a serving base station in accordance with a preferred embodiment of the present invention;

4 is a block diagram 2 of an apparatus for determining a serving base station in accordance with a preferred embodiment of the present invention;

Figure 5 is a block diagram 3 of an apparatus for determining a serving base station in accordance with a preferred embodiment of the present invention;

6 is a block diagram 4 of an apparatus for determining a serving base station in accordance with a preferred embodiment of the present invention;

7 is a flowchart 1 of a method for determining a serving base station according to a preferred embodiment of the present invention;

8 is a flowchart 2 of a method for determining a serving base station according to a preferred embodiment of the present invention;

9 is a schematic diagram of an effect comparison before and after optimization of a base station according to a preferred embodiment of the present invention.

detailed description

The invention will be described in detail below with reference to the drawings in conjunction with the embodiments. It should be noted that the embodiments in the present application and the features in the embodiments may be combined with each other without conflict.

In this embodiment, a method for determining a serving base station is provided. FIG. 1 is a flowchart of a method for determining a serving base station according to an embodiment of the present invention. As shown in FIG. 1, the process includes the following steps:

Step S102, determining a central average path loss value between the N base stations of the ultra-dense network UDN and the central user, and an edge average path loss value between the N base stations and the edge users, wherein the central user is the N base stations. a user within a predetermined range of services for which the edge user serves the user outside the predetermined range of the N base stations;

Step S104: Determine a base station for serving from the N base stations according to the central average path loss value and the edge average path loss value.

Through the above steps, determining a central average path loss value between the N base stations of the ultra-dense network UDN and the central user and an edge average path loss value between the N base stations and the edge users, wherein the central user is the N a user within a predetermined range of the base station service, the user outside the predetermined range served by the edge user for the N base stations, determined from the N base stations according to the central average path loss value and the edge average path loss value The serviced base station solves the problem that the allocation of the base station in the ultra-dense network UDN in the related art is unreasonable and the system interference is too large, thereby achieving the effect of reducing inter-base station interference and improving system performance.

As a preferred embodiment, the base station for serving is determined from the N base stations according to the central average path loss value and the edge average path loss value by using the following formula:

Wherein, OF is a parameter value of a base station for determining a service, f _{1 is} the center average path loss value, and f _{2 is} the edge average path loss value.

As a preferred embodiment, the central average path loss value is determined according to the following formula:

Where w _k =|C ^k |/K,

As a preferred embodiment, the edge average path loss value is determined according to the following formula:

Where w _k =|C ^k |/K,

As a preferred implementation manner, determining, according to the value of OF, the base station for serving includes: closing a base station corresponding to a minimum OF value in the OF value, determining a base station for serving from the N base stations, thereby reducing the base station. Mutual interference increases the performance of the system.

In another aspect of the present invention, a device for determining a serving base station is provided, and the device is used to implement the foregoing embodiments and preferred embodiments, and details are not described herein. As used below, the term "module" may implement a combination of software and/or hardware of a predetermined function. Although the apparatus described in the following embodiments is preferably implemented in software, hardware, or a combination of software and hardware, is also possible and contemplated.

2 is a block diagram of an apparatus for determining a serving base station according to an embodiment of the present invention. As shown in FIG. 2, the method includes: a first determining module 22 and a second determining module 24. The following describes each module.

The first determining module 22 is configured to determine a central average path loss value between the N base stations of the ultra-dense network UDN and the central user, and an edge average path loss value between the N base stations and the edge user, where the central user a user within a predetermined range serving the N base stations, the edge users serving the N base stations outside the predetermined range of users;

The second determining module 24 is configured to determine a base station for serving from the N base stations according to the central average path loss value and the edge average path loss value.

3 is a block diagram of an apparatus for determining a serving base station according to a preferred embodiment of the present invention. As shown in FIG. 3, the apparatus further includes:

The first calculating module 32 is configured to determine, by using the following formula, a base station for serving from the N base stations according to the central average path loss value and the edge average path loss value:

4 is a block diagram 2 of an apparatus for determining a serving base station according to a preferred embodiment of the present invention. As shown in FIG. 4, the apparatus further includes:

The second calculation module 42 is configured to determine the central average path loss value according to the following formula:

Where w _k =|C ^k |/K,

5 is a block diagram 3 of an apparatus for determining a serving base station according to a preferred embodiment of the present invention. As shown in FIG. 5, the apparatus further includes:

The third calculating module 52 is configured to determine the edge average path loss value according to the following formula:

Where w _k =|C ^k |/K,

Where g _j ^(k) is the path loss between the jth user and the kth base station; g _j.max represents the maximum allowable path loss, calculated by the following formula: g _j,max =(P ₀ )dBm -(N ₀ B)dBm-(F)dB-(SNR _jmin )dB, P ₀ represents the base station transmit power, N0 represents the noise power spectral density, B represents the channel bandwidth, F represents the receive noise figure, and SNRj, min is expressed in The minimum signal to noise ratio threshold at j users; C ^k is the set of users served by the small base station k, |C ^k | is the total number of users served by the small base station k; C ₁ takes an integer in the range, when C _{When 1} =|C ^k |, the central average path loss value is the average path loss value between all service users and the serving base station.

FIG. 6 is a block diagram 4 of an apparatus for determining a serving base station according to a preferred embodiment of the present invention. As shown in FIG. 6, the apparatus further includes:

The third determining module 62 is configured to determine, according to the value of the OF, the base station for serving, that: the base station corresponding to the minimum OF value of the OF value is turned off, and the base station for serving is determined from the N base stations.

In another aspect of the embodiments of the present invention, a base station is provided, including at least one of the foregoing devices.

The embodiments of the present invention are further described below in conjunction with the preferred embodiments.

In the related art, in the case where the user mobility is high, due to the high mobility of the user, the uncertainty of the distribution of the user in a specific coverage area with time changes. Within the coverage of a fixed small cell base station group, due to this uncertainty, the throughput of the network changes with time. For example, at a certain time, users are concentrated in a small part of the coverage of the small cell base station group, which causes other small cell base stations to generate resources idle and reduce spectrum efficiency. Or at a certain time, the user is distributed at the edge of the small cell. At this time, the small cell base station side needs a large transmission power, which will cause large interference to the users in the same frequency band of the adjacent small cells, and the adjacent small cell edge When there are many users, the interference is especially serious.

In another case, the user service distribution is relatively unchanged over a long period of time. For example, in a relatively long period of time, a certain floor in an office building is rented to a company as an employee office area, but For various reasons, this floor is subletted to an educational institution for use as a classroom. When the office area changes to the classroom, the user distribution status also changes. Therefore, the original small cell base station deployment cannot match the current user distribution status. The system performance is thus degraded.

For the above problem, the embodiment of the present invention provides a method for optimizing the location of a small Cell base station in a UDN environment. After optimizing the deployment of the original small cell base station, the signal to noise ratio of the user can be improved, and the system performance is optimized. Not only can improve system resource utilization but also save power and reduce interference.

For the case of high user mobility, N small cell base stations are preset, numbered S ₁ , S ₂ , . . . , S _N , and each small cell base station allows access; In the scenario where the distribution is constant in the time period, K small cell base stations are deployed in the original state, and NK small cell base stations are additionally added before the optimization, and N small cell base stations are obtained, numbered as S ₁ , S ₂ , ..., S _N , each small cell base station allows access. In summary, in the two scenarios, N small cell base stations whose initial states are optimized to be fixed positions are optimized. The number of optimized small cell base station targets is preset to K.

The optimization algorithm proposed by the embodiment of the present invention is based on two optimization targets for maximizing the average signal quality of the central user of the entire service area and minimizing the difference of signal quality. Determining the base station for service from the N base stations based on the central average path loss value and the edge average path loss value:

Determine the center average path loss value according to the following formula:

Where w _k =|C ^k |/K,

The edge average path loss value is determined according to the following formula:

Where w _k =|C ^k |/K,

The method for optimizing the location of the small cell base station specifically includes: for the N small cell base stations with the numbers S ₁ , S ₂ , . . . , S _N in the initial state, obtaining the path loss between the J and the jth user according to the above criteria. The smallest k-th base station acts as an access base station, and separately counts the OF value, and compares and finds the single small-cell base station S _j with the smallest OF value to close or remove the small-cell base station; and sets the remaining small-cell base station {S ₁ , S ₂ Step S2 is continued in S _N }; step S3 is repeated until the number of remaining small cell base stations is the number of optimized small cell base station targets.

Wherein, in a scenario where the user has high mobility, a method of shutting down the small cell base station is adopted, and all the small cell base stations are reactivated and the above optimization algorithm is implemented at intervals; and the mobility of the other user is relatively low. In the scenario, the method of removing the small cell base station is adopted to achieve a small cell base station arrangement pattern that matches the current user distribution.

In the embodiment of the present invention, aiming at an area that maximizes the average signal quality of the central user of the service area and minimizes the difference in signal quality, the small cell base station that affects the target is closed or removed, thereby achieving the purpose of optimizing the location of the small cell base station, thereby Improve system performance. It is especially suitable for UDNs where the small cell base station is extremely dense.

FIG. 7 is a flowchart 1 of a method for determining a serving base station according to a preferred embodiment of the present invention. As shown in FIG. 7, in a high mobility scenario of a user, performing location optimization on a small cell base station includes the following steps:

Step S702, initializing and activating N base stations;

Step S704, calculating and comparing the OF of each base station;

Step S706, turning off the base station with the smallest OF value;

Step S708, it is checked whether the number of remaining base stations has dropped to K, if yes, step S710 is performed, otherwise step S704 is performed;

In step S710, it is checked whether the preset interval time is reached. If yes, step S702 is performed, otherwise step S710 is performed.

FIG. 8 is a second flowchart of a method for determining a serving base station according to a preferred embodiment of the present invention. As shown in FIG. 8, the user performs location optimization on a small cell base station in a relatively low mobility scenario, including the following steps:

Step S802, adding N-Ks to the original K base stations according to the original deployment rule;

Step S804, initializing and activating N base stations;

Step S806, calculating and comparing the OF values of the respective base stations;

Step S808, removing the base station with the smallest OF value;

Step S810, it is checked whether the number of remaining base stations has dropped to K, and then the optimization is completed, otherwise step S806 is performed.

FIG. 9 is a schematic diagram of the effect comparison before and after optimization of a base station according to a preferred embodiment of the present invention. As shown in FIG. 9 , in a high-speed mobility environment of a user, 12 small cell base stations are originally deployed in a grid shape, and the users are evenly distributed. In the coverage area, the illustrated results are obtained after optimization by the scheme. As shown in the figure, it can be seen that the location of the small cell base station before optimization and the location of the optimized small cell base station are completely different. The optimization method of the embodiment of the present invention optimizes the base station, which not only improves system resource utilization but also saves Power, reduce interference.

It will be apparent to those skilled in the art that the various modules or steps of the present invention described above can be implemented by a general-purpose computing device that can be centralized on a single computing device or distributed across a network of multiple computing devices. Alternatively, they may be implemented by program code executable by the computing device such that they may be stored in the storage device by the computing device and, in some cases, may be different from the order herein. The steps shown or described are performed, or they are separately fabricated into individual integrated circuit modules, or a plurality of modules or steps thereof are fabricated as a single integrated circuit module. Thus, the invention is not limited to any specific combination of hardware and software.

The above description is only the preferred embodiment of the present invention, and is not intended to limit the present invention, and various modifications and changes can be made to the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and scope of the present invention are intended to be included within the scope of the present invention.

Industrial applicability

As described above, the above embodiments and the preferred embodiments solve the problem that the allocation of the base stations in the ultra-dense network UDN in the related art is unreasonable and the system interference is too large, thereby achieving the effect of reducing interference between the base stations and improving system performance.

Claims

A method for determining a serving base station, comprising:

Determining a central average path loss value between the N base stations of the ultra-dense network UDN and a central user and an edge average path loss value between the N base stations and an edge user, wherein the central user is the N base stations a user within a predetermined range of services, the edge user serving the user outside the predetermined range of the N base stations;

Determining a base station for serving from the N base stations based on the central average path loss value and the edge average path loss value.
The method according to claim 1, wherein the base station for serving is determined from the N base stations based on the central average path loss value and the edge average path loss value by the following formula:

Wherein, OF is a parameter value of a base station for determining a service, f 1 is the central average path loss value, and f 2 is the edge average path loss value.
The method of claim 2, wherein the central average path loss value is determined according to the following formula:

Where w k =|C k |/K,

u denotes a penalty factor and takes a constant. For the determined serving small base station k, the relative path loss between all users and the small base station is:

Where g j (k) is the path loss between the jth user and the kth base station;

g j.max represents the maximum allowable path loss, calculated by the following formula: g j,max =(P 0 )dBm-(N 0 B)dBm-(F)dB-(SNR jmin )dB, P 0 represents the base station Transmit power, N 0 represents the noise power spectral density, B represents the channel bandwidth, F represents the received noise figure, and SNR j, min represents the minimum signal to noise ratio threshold at the jth user;

C k is the set of users served by the small base station k, |C k | is the total number of users served by the small base station k; C 1 takes an integer in the range, and when C 1 =|C k |, the center average path loss The value is the average path loss value between all service users and the serving base station.
The method of claim 2, wherein the edge average path loss value is determined according to the following formula:

Where w k =|C k |/K,

u denotes a penalty factor and takes a constant. For the determined serving small base station k, the relative path loss between all users and the small base station is:

Where g j (k) is the path loss between the jth user and the kth base station;

g j.max represents the maximum allowable path loss, calculated by the following formula: g j,max =(P 0 )dBm-(N 0 B)dBm-(F)dB-(SNR jmin )dB, P 0 represents the base station Transmit power, N 0 represents the noise power spectral density, B represents the channel bandwidth, F represents the received noise figure, and SNR j, min represents the minimum signal to noise ratio threshold at the jth user;

C k is the set of users served by the small base station k, |C k | is the total number of users served by the small base station k; C 1 takes an integer in the range, and when C 1 =|C k |, the center average path loss The value is the average path loss value between all service users and the serving base station.
The method according to claim 2, wherein determining the base station for serving according to the value of the OF comprises: turning off a base station corresponding to a minimum OF value of the OF values, determining from the N base stations for serving Base station.
A device for determining a serving base station, comprising:

a first determining module, configured to determine a central average path loss value between the N base stations of the ultra-dense network UDN and a central user, and an edge average path loss value between the N base stations and an edge user, wherein the center a user within a predetermined range served by the user for the N base stations, the edge user serving the user outside the predetermined range served by the N base stations;

And a second determining module, configured to determine, from the N base stations, a base station for serving according to the central average path loss value and the edge average path loss value.
The apparatus of claim 6 wherein said apparatus further comprises:

a first calculating module, configured to determine, by the following formula, a base station for serving from the N base stations according to the central average path loss value and the edge average path loss value:
Wherein, OF is a parameter value of a base station for determining a service, f 1 is the central average path loss value, and f 2 is the edge average path loss value.
The apparatus of claim 6 wherein said apparatus further comprises:

The second calculation module is configured to determine the central average path loss value according to the following formula:

Where w k =|C k |/K,

u denotes a penalty factor and takes a constant. For the determined serving small base station k, the relative path loss between all users and the small base station is:

Where g j (k) is the path loss between the jth user and the kth base station;

g j.max represents the maximum allowable path loss, calculated by the following formula: g j,max =(P 0 )dBm-(N 0 B)dBm-(F)dB-(SNR jmin )dB, P0 denotes base station transmission Power, N0 represents the noise power spectral density, B represents the channel bandwidth, F represents the received noise figure, and SNRj, min represents the minimum signal to noise ratio threshold at the jth user;

C k is the set of users served by the small base station k, |C k | is the total number of users served by the small base station k; C 1 takes an integer in the range, and when C 1 =|C k |, the center average path loss The value is the average path loss value between all service users and the serving base station.
The apparatus of claim 6 wherein said apparatus further comprises:

The third calculation module is configured to determine the edge average path loss value according to the following formula:

Where w k =|C k |/K,

u denotes a penalty factor and takes a constant. For the determined serving small base station k, the relative path loss between all users and the small base station is:

Where g j (k) is the path loss between the jth user and the kth base station;

g j.max represents the maximum allowable path loss, calculated by the following formula: g j,max =(P 0 )dBm-(N 0 B)dBm-(F)dB-(SNR jmin )dB, P0 denotes base station transmission Power, N0 represents the noise power spectral density, B represents the channel bandwidth, F represents the received noise figure, and SNRj, min represents the minimum signal to noise ratio threshold at the jth user;

C k is the set of users served by the small base station k, |C k | is the total number of users served by the small base station k; C 1 takes an integer in the range, and when C 1 =|C k |, the center average path loss The value is the average path loss value between all service users and the serving base station.
The apparatus of claim 6 wherein said apparatus further comprises:

The third determining module is configured to determine, according to the value of the OF, the base station for serving, comprising: turning off a base station corresponding to a minimum OF value of the OF values, and determining a base station for serving from the N base stations.
A base station comprising at least the apparatus of any one of claims 6-10.