LOAD ESTIMATION FOR A CELL IN A WIRELESS NETWORK

• US 20100135170A1
• Filed: 01/18/2007
• Published: 06/03/2010
• Est. Priority Date: 01/18/2007
• Status: Active Grant

• Current Assignee: Telefonaktiebolaget LM Ericsson
• Original Assignee: Telefonaktiebolaget LM Ericsson
• Inventors: Fan, Rui, Ericson, Marten
• Granted Patent: US 8,045,527 B2
• Time in Patent Office: Days
• US Class Current: 370/252
• CPC Class Codes: H04W 24/02 Arrangements for optimising operational condition
• CPC Class Codes: H04W 28/16 Central resource management; Negotiation of resources or communication parameters, e.g. negotiating bandwidth or QoS [Quality of Service]

Abstract

The invention is directed towards a method of estimating the load on a cell in a wireless network as well as to a cell load estimating device. According to the invention a determination (46) is made of a value (R) indicative of the degree of use, by a mobile station provided in a set of mobile stations connected to a cell, of a communication link provided for this mobile station during a communication session. Based on this value an adjusted link quality value (L-ADJUST) is provided (54) for the mobile station, which is then used when determining the cell load.

Claims

1. Method of estimating the load on a cell (11) in a wireless network, to which cell a number of mobile stations (16) are connected, comprising the steps of:

obtaining (38, 56) measurement data (RC, PV, I) of the radio conditions of the links between said mobile stations and said cell,

determining (30, 42, 54) link quality values based on the obtained measurement data, and

summing (32) the link quality values related to the mobile stations of the cell in order to estimate the total load (LTOT),

wherein said method further comprises the steps of, for each mobile station (16) in a set of mobile stations connected to said cell,

determining (46) a value (R) indicative of the degree of use, by the mobile station, of a communication link provided for the mobile station during a communication session, and providing (54) an adjusted link quality value for the mobile station that considers this value indicative of degree of use of said link.

2. Method according to claim 1, wherein said value (R) indicative of the degree of use is determined based on an estimation of the time occupied for sending data by the mobile station in relation to a granted time interval for such sending of data on the link for the mobile station.

3. Method according to claim 2, wherein the estimation of the time occupied for sending data in relation to the granted time interval is determined through determining the number of data packets transmitted from the mobile station in relation to a number of assigned transmission time intervals within the granted time interval.

4. Method according to claim 3, wherein said estimation of the time occupied for sending data is also determined based on the number of data packets retransmitted by the mobile station.

5. Method according to claim 2, wherein said value indicative of the degree of use is continuously re-determined while the link is being used for sending data in the communication session.

6. Method according to claim 1, wherein the measurement data relating to the mobile station in the set is a transmission power value (PV) used by the mobile station in relation to the link between the mobile station and the cell, and said value indicative of the degree of use is being used for adjusting a power value associated with a specific channel on said link between the mobile station and the cell when determining link quality.

7. Method according to claim 6, wherein said transmission power value is provided for a first channel of the link and the value indicative of the degree of use is being used in relation to an adjusted link quality value (L-ADJUST) for a second data transmission channel of the link that is based on a transmission power that is offset from the power indicated by said transmission power value of this first channel.

8. Method according to claim 1, wherein the step of providing an adjusted link quality value comprises adjusting a temporary current link quality value (L-TEMP) that has been determined based on a current value indicative of the degree of use with a previous link quality value (L-PREV).

9. Method according to claim 8, where if the current value indicative of the degree of use is the first such value, the previous link quality value is an unadjusted link quality value and otherwise it is a previous adjusted link quality value.

10. Method according to claim 1, further comprising the steps of determining that the session is no longer ongoing and stopping determining the degree of use and providing adjusted link quality values based on this determination.

13. Method according to claim 1, further comprising the step of obtaining an indicator for each mobile station of the type of service it is engaged in and selecting if a mobile station is to be provided in the set or not based on said indicator.

11. Method according to claim 11, wherein the step of determining that the session is no longer ongoing comprises comparing the adjusted link quality value with an unadjusted link quality value provided for the link and performing the step of stopping determining the degree of use and providing adjusted link quality values if this unadjusted value is lower than the adjusted value and setting this unadjusted value as the link quality value.

12. Method according to claim 11, further comprising the step of detecting a session indication system signal (SC) and setting the unadjusted link quality value used in the comparison to be a link quality value that is a basic link quality value associated with a first channel of the link if the signal indicates no communication session and as a link quality value being offset from the basic link quality value with an offset associated with a second data transmission channel of the link if the signal indicates the existence of a session.

14. Cell load estimating device (22) for a cell (11) in a wireless network, to which cell a number of mobile stations (16) are connected comprising:

a data obtaining unit (28) configured to obtain measurement data (RC, PV, I) of the radio conditions of the uplinks between said mobile stations and said cell, and a cell load estimating unit (26) configured to

determine link quality values based on the obtained measurement data,

sum the link quality values related to the mobile stations of the cell in order to estimate the total load (LTOT), and

for each mobile station (16) in a set of mobile stations connected to said cell,

determine a value (R) indicative of the degree of use, by the mobile station, of a communication link provided for the mobile station during a communication session, and

provide an adjusted link quality value (L-ADJUST) for the mobile station that considers this value indicative of degree of use of said link.

15. Cell load estimating device according to claim 14, wherein it provided in a cell handling device (10).