Method and device for selecting heterogeneous network serving cell based on inter-cell cooperation

Patent metadata

Field	Value
Publication number	US-10015730-B2
Application number	US-201515513764-A
Country	US
Kind code	B2
Filing date	Mar 18, 2015
Priority date	Sep 26, 2014
Publication date	Jul 3, 2018
Grant date	Jul 3, 2018

Abstract

A method and device for selecting a heterogeneous network serving cell based on inter-cell cooperation, which relate to the field of digital communications. The method disclosed in the embodiments of the present invention comprises: acquiring, by a central node base station in a heterogeneous network, alternative users in each cell in the heterogeneous network; and according to a pre-set alternative user selection criterion, selecting an alternative user in the entire network from the alternative users in all cells in the heterogeneous network; and if the alternative user in the entire network needs to conduct a reselection operation, initiating a cell reselection flow. Also disclosed is a device for selecting a heterogeneous network serving cell based on inter-cell cooperation corresponding to the method.

First claim

What is claimed is:

1. A method for selecting a heterogeneous network serving cell based on inter-cell cooperation, comprising:
obtaining, by a central node base station in a heterogeneous network, alternative users in each cell in the heterogeneous network, and selecting an alternative user in the entire network from the alternative users in all cells in the heterogeneous network according to a pre-set alternative user selection criterion; and
if the alternative user in the entire network needs to perform a reselection operation, initiating a cell reselection flow;
wherein the pre-set alternative user selection criterion comprises one or more of the following: a system rate maximizing criterion, a degree of freedom restoring criterion, or a frequency reuse criterion;
wherein the system rate maximizing criterion is: selecting the user with the maximum rate ratio R m (q)/R m (j) in the rate ratios R m (q)/R m (j) of cell reselection of all users as the alternative user, wherein R m (q) is the rate obtained in the reselected cell by the user m, and R m (j) is the rate obtained in the current serving cell j by the user m;
wherein the degree of freedom restoring criterion is: in a spatial beam joint selection algorithm in a set time, selecting the user with the maximum number of beam closing times in the numbers of beam closing times of all users as the alternative user;
wherein the frequency reuse criterion is: selecting the user with the maximum Fractional Frequency Reuse (FFR) in the FFRs of all users in the set time as the alternative user.

2. The method according to claim 1 , further comprising:
selecting in this cell, by each cell base station in the heterogeneous network, the alternative users in a cell according to the pre-set alternative user selection criterion, and reporting the selected alternative users in the cell to the central node base station.

3. The method according to claim 1 , wherein determining the rate ratio R m (q)/R m (j) of cell reselection of the user according to the following process:
calculating the R m (q) and the R m (j) respectively, so as to obtain the rate ratio R m (q)/R m (j) of cell reselection of the users;
wherein, determining the rate obtained in each cell by each user according to the following formula:

R
m

⁡

(

q
*

)

=

∑

k
⋐
K

⁢

⁢

G
⁡

(

y

q
*

,
k

)

⁢

E
⁡

(

R

k
,
m
,

q
*

)

y

q
*

,
k

where, R m (q*) is the rate obtained in the cell q* by the user m;
E(R k,m,q *) is the mathematical expectation of R k,m,q * R k,m,q * is the instantaneous average maximum data rate that the user m can realize on the carrier k of the cell q*, and K is the total number of carriers in the cell q*;
y q * ,k =Σ m⊂M x m,q * is the number of users accessing the cell q*; when x m,q * is equal to 1, q* is the serving cell of the user m; when x m,q * is equal to 0, q* is not the serving cell of the user m; M is the total number of users supported by the cell q*;

G
⁡

(

y

q
*

,
k

)

=

∑

m
=
1

y

q
*

,
k

⁢

⁢

1
m

is a diversity gain of multiple users.

4. The method according to claim 1 , wherein in the spatial beam joint selection algorithm in the set time, the process of determining the number of beam closing times of the user is as follows:
iteratively calculating parameters A and b k,q when the overall system rate is the maximum, and counting the number of beam closing times of each user in the process of calculating the parameters A and b k,q when the overall system rate is the maximum;
wherein, calculating the overall system rate R composed of Q cells according to the following formula:
R=Σ q=1 Q Σ k=1 K log 2 (1+ a k,q SINR k,m,q );

where, K is the number of carriers in the cell q;
SINR k,m,q is the Signal to Interference plus Noise Ratio (SINR) of the user m in a block fading scenario on the carrier k in the cell q;
when a k,q is equal to 1, the carrier k in the cell q is allocated to the user m; when a k,q is equal to 0, the carrier k in the cell q is not allocated to the user m.

5. The method according to claim 1 , wherein calculating the FFR of the user according to the following formula:
FFR=FFR 1 ·P 1 +FFR 2 ·P 2 ±FFR 3 ·P 3 +L +FFR Q ·P Q ;

where, FFR 1 −1/3, FFR 2 =2/3, FFR 3 =1, and FFR Q =1/Q;
and P 1 , P 2 , L P Q are weighting coefficients.

6. A non-transitory computer readable storage medium, in which a computer program is stored; the computer program comprises a program instruction; when the program instruction is executed by a base station device, the device performs a method according to claim 1 .

Assignees

• Zte Corp

Inventors

• Wang Shaopeng
• Qin Hongfeng

Classifications

• H04W48/20

  Selecting an access point · CPC title

• H04W48/16 Primary

  Discovering, processing access restriction or access information · CPC title

• H04W72/0453

  Resources in frequency domain, e.g. a carrier in FDMA · CPC title

• H04W36/0005

  Control or signalling for completing the hand-off · CPC title

• H04W36/08

  Reselecting an access point · CPC title