Overall network performance and/or overall quality of service of a mobile communication network by assigning a physical cell identifier information to a plurality of radio cells

• US 10,334,490 B2
• Filed: 02/12/2016
• Issued: 06/25/2019
• Est. Priority Date: 03/10/2015
• Status: Active Grant

• Current Assignee: Deutsche Telekom AG
• Original Assignee: Deutsche Telekom AG
• Inventors: Zingler, Olaf
• Primary Examiner(s): Crompton, Christopher R
• Application Number:
  US15/554,716
• Publication Number:
  US 20180279187A1
• Time in Patent Office: 1,229 Days
• Field of Search: 370331
• CPC Class Codes: H04W 16/18 Network planning tools
• CPC Class Codes: H04W 24/02 Arrangements for optimising operational condition
• CPC Class Codes: H04W 36/00837 Determination of triggering parameters for hand-off
• CPC Class Codes: H04W 36/08 Reselecting an access point

Abstract

A method for improving overall network performance and/or overall quality of service of a mobile communication network by assigning physical cell identifier information to a plurality of radio cells includes: in a first step and for each of a plurality of coverage area elements of a common radio coverage area, generating a set of handover likelihood information; in a second step, calculating, based on elements of the sets of handover likelihood information, an overlap score value indicative of the overlap between at least one source radio cell and at least one target radio cell; and in a third step, assigning the physical cell identifier information to the at least one source radio cell and/or the at least one target radio cell dependent on the overlap score value.

Claims

1. A method for improving overall network performance and/or overall quality of service of a mobile communication network by assigning physical cell identifier information to a plurality of radio cells, wherein the mobile communication network comprises a core network and an access network, the access network comprising the plurality radio cells, wherein the plurality of radio cells are at least partly overlapping, forming a common radio coverage area, each radio cell of the plurality of radio cells being associated with a respective base station entity of a plurality of base station entities, each radio cell of the plurality of radio cells using a center frequency, and a unique cell global identifier information being assigned to each radio cell of the plurality of radio cells, wherein the method comprises the following steps:

in a first step and for each of a plurality of coverage area elements of the common radio coverage area, generating a set of handover likelihood information—

regarding possible inter-frequency handover events between at least part of the plurality of radio cells and based on an estimated radio signal quality corresponding to the considered coverage area element—

each element of the set of handover likelihood information being indicative of a possibility and/or a likelihood of a handover of the user equipment from at least one possible source radio cell of the plurality of radio cells to at least one possible target radio cell of the plurality of radio cells, the at least one source radio cell and the at least one target radio cell having, respectively, center frequencies in different frequency bands;

in a second step, calculating, based on the elements of the sets of handover likelihood information—

among the sets of handover likelihood information associated with the plurality of coverage area elements of the common radio coverage area—

related to the at least one source radio cell and the at least one target radio cell, an overlap score value indicative of the overlap between the at least one source radio cell and the at least one target radio cell; and

in a third step, assigning the physical cell identifier information to the at least one source radio cell and/or the at least one target radio cell dependent on the overlap score value;

wherein the set of handover likelihood information, generated with respect to a considered coverage area element of the common radio coverage area, comprises a weighting factor, the weighting factor being dependent on at least one out of the following;

an indication related to the amount or to the density of real time traffic in the coverage area element;

an indication related to the amount or to the density of non-real time traffic in the coverage area element;

an indication related to the digital land usage in the coverage area element;

an indication related to the mobility of the user equipments in the coverage area element;

a vector data set in the coverage area element related to a street and/or a motorway and/or a train line;

or

an indication related to the type of the source radio and/or to the type of the target radio cell and/or an indication related to the type of the relationship between the source and target radio cell.

2. The method according to claim 1, wherein the estimated radio signal quality—

related to a considered coverage area element of the common radio coverage area—

based on which the set of handover likelihood information is generated, corresponds to radio signal quality experienced by a user equipment in case it is located at or within the considered area element.

3. The method according to claim 1, wherein the possibility and/or the likelihood of a handover—

related to a considered coverage area element of the common radio coverage area—

from a possible source radio cell to a possible target radio cell of the plurality of radio cells is assumed to be verified if the estimated value of the reference signal received power (RSRP) verifies a reference signal received power being lower than or equal to −

110 dBm for the possible source radio cell and a reference signal received power being higher than or equal to −

105 dBm, or a reference signal received power being lower than or equal to the sum of a first offset value and −

110 dBm for the possible source radio cell and a reference signal received power being higher than or equal to the sum a second offset value and −

105 dBm.

4. The method according to claim 1, wherein the possibility and/or the likelihood of a handover—

related to a considered coverage area element of the common radio coverage area—

from a possible source radio cell to a possible target radio cell of the plurality of radio cells is assumed to be verified if the estimated value of the reference signal received power (RSRP) verifies a reference signal received power being lower than or equal to −

110 dBm for the possible source radio cell and a reference signal received power of a possible target cell being higher than or equal to 5 dB of the reference signal of the possible source cell, or a reference signal received power being lower than or equal to the sum of a first offset value and 110 dBm for a possible source radio cell and a reference signal received power of a possible target cell being higher than or equal to the sum of a second offset value and 5 dB in relation to a reference signal of the possible source cell.

5. The method according to claim 1, wherein the possibility and/or the likelihood of a handover—

related to a considered coverage area element of the common radio coverage area—

from a possible source radio cell to a possible target radio cell of the plurality of radio cells is assumed to be verified if the estimated value of the reference signal received power (RSRP) verifies modified threshold conditions, wherein the modified threshold conditions are modified to reflect special radio signal quality influencing conditions, including an additional loss of radio signal quality due to indoor conditions within at least part of the considered coverage area element.

6. The method according to claim 1, wherein the weighting factor is further dependent on at least one out of the following:

the number of user equipments in the coverage area element;

an indication of the density of user equipments in the coverage area element in relation to the total amount of user equipments in the considered access network;

or

an indication of the population or the density of population in the coverage area element.

7. The method according to claim 1, wherein for each of the plurality of coverage area elements, the set of handover likelihood information comprises at least one element of handover likelihood information related to the one radio cell of the plurality of radio cells, as a possible source radio cell, that has a highest estimated value of radio signal quality.

8. The method according to claim 1, wherein for each of the plurality of coverage area elements, the set of handover likelihood information comprises—

additionally to the one element of handover likelihood information related to the one radio cell that has a highest estimated value of radio signal quality—

at least one element of handover likelihood information related to a possible source radio cell of the plurality of radio cells if at least one of the following conditions are fulfilled;

the difference between the estimated value of radio signal quality related to the possible source radio cell of the plurality of radio cells compared to the highest estimated value of radio signal quality of a radio cell within the same frequency band is less than a predetermined threshold of radio signal quality;

or

number of possible source radio cells within the same frequency band for which at least one element of handover likelihood information is generated does not exceed a predetermined threshold number.

9. The method according to claim 1, wherein different elements of handover likelihood information of a set of handover likelihood information—

related to a considered coverage area element of the common radio coverage area—

comprise a cell assignment probability weighting factor, the cell assignment probability weighting factor increasing or decreasing the respective overlap score value in case that more than one element of handover likelihood information is generated, for a considered coverage area element of the common radio coverage area, for radio cells within one frequency band.

10. The method according to claim 1, wherein assigning the physical cell identifier information to the at least one source radio cell and/or the at least one target radio cell dependent on the overlap score value further comprises assigning different physical cell identifier information to at least two possible target radio cells—

having the same frequency band and being related to the same source radio cell in case that;

the respective overlap score value exceeds a predetermined maximum allowed overlap score threshold; and

/or

the sum of the respective overlap score values exceeds a predetermined maximum allowed overlap score threshold; and

/or

the sum of the respective overlap score values exceeds a predetermined maximum allowed overlap score threshold, whereby each overlap score has to be larger than a further minimum threshold; and

/or

a mathematical algorithm for the purpose of physical cell identifier planning and or optimization calculates this according to an implemented mathematical cost-function whereby the overlap score is the input parameter or is a part of the input parameters of this cost-function.

11. A mobile communication network for improving overall network performance and/or overall quality of service by assigning a physical cell identifier information to a plurality of radio cells, wherein the mobile communication network comprises:

a core network; and

an access network, the access network comprising the plurality radio cells, wherein the plurality of radio cells are at least partly overlapping, forming a common radio coverage area, each radio cell of the plurality of radio cells being associated with a respective base station entity of a plurality of base station entities, each radio cell of the plurality of radio cells using a center frequency, and a unique cell global identifier information being assigned to each radio cell of the plurality of radio cells;

wherein the mobile communication network is configured to generate a set of handover likelihood information for each of a plurality of coverage area elements of the common radio coverage area—

regarding possible inter-frequency handover events between at least part of the plurality of radio cells and based on an estimated radio signal quality corresponding to the considered coverage area element—

each element of the set of handover likelihood information being indicative of a possibility and/or a likelihood of a handover of the user equipment from at least one possible source radio cell of the plurality of radio cells to at least one possible target radio cell of the plurality of radio cells, the at least one source radio cell and the at least one target radio cell having, respectively, center frequencies in different frequency bands;

wherein the mobile communications network is further configured to calculate, based on the elements of the sets of handover likelihood information—

among the sets of handover likelihood information associated with the plurality of coverage area elements of the common radio coverage area—

related to the at least one source radio cell and the at least one target radio cell, an overlap score value being indicative of the overlap between the at least one source radio cell and the at least one target radio cell; and

wherein the mobile communications network is further configured to assign the physical cell identifier information to the at least one source radio cell and/or the at least one target radio cell dependent on the overlap score value;

wherein the set of handover likelihood information, generated with respect to a considered coverage area element of the common radio coverage area, comprises a weighting factor, the weighting factor being dependent on at least one out of the following;

an indication related to the amount or to the density of real time traffic in the coverage area element;

an indication related to the amount or to the density of non-real time traffic in the coverage area element;

an indication related to the digital land usage in the coverage area element;

an indication related to the mobility of the user equipments in the coverage area element;

a vector data set in the coverage area element related to a street and/or a motorway and/or a train line;

or

an indication related to the type of the source radio and/or to the type of the target radio cell and/or an indication related to the type of the relationship between the source and target radio cell.

12. A non-transitory computer-readable medium having processor-executable instructions stored thereon for improving overall network performance and/or overall quality of service of a mobile communication network by assigning physical cell identifier information to a plurality of radio cells, wherein the mobile communication network comprises a core network and an access network, the access network comprising the plurality radio cells, wherein the plurality of radio cells are at least partly overlapping, forming a common radio coverage area, each radio cell of the plurality of radio cells being associated with a respective base station entity of a plurality of base station entities, each radio cell of the plurality of radio cells using a center frequency, and a unique cell global identifier information being assigned to each radio cell of the plurality of radio cells, wherein the processor-executable instructions, when executed, facilitate performance of the following steps:

in a first step and for each of a plurality of coverage area elements of the common radio coverage area, generating a set of handover likelihood information—

regarding possible inter-frequency handover events between at least part of the plurality of radio cells and based on an estimated radio signal quality corresponding to the considered coverage area element—

each element of the set of handover likelihood information being indicative of a possibility and/or a likelihood of a handover of the user equipment from at least one possible source radio cell of the plurality of radio cells to at least one possible target radio cell of the plurality of radio cells, the at least one source radio cell and the at least one target radio cell having, respectively, center frequencies in different frequency bands;

in a second step, calculating, based on the elements of the sets of handover likelihood information—

among the sets of handover likelihood information associated with the plurality of coverage area elements of the common radio coverage area—

related to the at least one source radio cell and the at least one target radio cell, an overlap score value indicative of the overlap between the at least one source radio cell and the at least one target radio cell; and

in a third step, assigning the physical cell identifier information to the at least one source radio cell and/or the at least one target radio cell dependent on the overlap score value;

wherein the set of handover likelihood information, generated with respect to a considered coverage area element of the common radio coverage area, comprises a weighting factor, the weighting factor being dependent on at least one out of the following;

an indication related to the amount or to the density of real time traffic in the coverage area element;

an indication related to the amount or to the density of non-real time traffic in the coverage area element;

an indication related to the digital land usage in the coverage area element;

an indication related to the mobility of the user equipments in the coverage area element;

a vector data set in the coverage area element related to a street and/or a motorway and/or a train line;

or

an indication related to the type of the source radio and/or to the type of the target radio cell and/or an indication related to the type of the relationship between the source and target radio cell.