System and method for channel assignment based upon interference and channel quality measurements

• US 6,240,275 B1
• Filed: 12/30/1998
• Issued: 05/29/2001
• Est. Priority Date: 12/30/1998
• Status: Expired due to Term

• Current Assignee: Ericsson, Inc. (Telefonaktiebolaget LM Ericsson)
• Original Assignee: Ericsson, Inc. (Telefonaktiebolaget LM Ericsson)
• Inventors: H'Mimy, Hossam H., Shah, Ali R.
• Primary Examiner(s): Nguyen, Lee
• Application Number:
  US09/224,069
• Time in Patent Office: 881 Days
• Field of Search: 455/62, 455/513, 455/450, 455/451, 455/452, 455/509, 455/512, 455/514, 455/436, 370/329, 370/332, 370/333
• US Class Current: 455/62
• CPC Class Codes: H04B 17/345 Interference values signal-to-interference ratio [SIR] or carrier-to-interference ratio [CIR] H04B17/336
• CPC Class Codes: H04B 17/382 for resource allocation, admission control or handover
• CPC Class Codes: H04W 24/00 Supervisory, monitoring or testing arrangements
• CPC Class Codes: H04W 36/06 Reselecting a communication resource in the serving access point
• CPC Class Codes: H04W 72/541 using the level of interference
• CPC Class Codes: H04W 72/542 using measured or perceived quality
• CPC Class Codes: H04W 84/042 Public Land Mobile systems, e.g. cellular systems

Abstract

A telecommunications system and method is disclosed for assigning channels based upon interference and channel quality measurements. The interference level measurements are carried out on the uplink of the cellular network. Channels are categorized in accordance with interference bands depending upon the interference levels. Incoming service is pre-assigned to a channel in the highest available interference band and a channel quality measurement (CQM) is conducted. The service is either continued (assigned) on the same channel, reassigned to a channel with lower interference or dropped if no other channel with lower interference is available based upon the channel quality measurement and the interference bands having available channels.

Claims

1. A base station within a cellular network for assigning channels to incoming service based upon interference measurements and channel quality measurements, comprising:

interference measurement logic for measuring interference values on each said channel assigned to said base station;

a first database for storing interference bands based upon said measured interference values;

channel quality measurement logic for measuring a channel quality value on a first channel associated with said base station and assigned to an incoming service, said first channel having an interference value associated therewith within a highest available one of said interference bands; and

decision logic for determining whether to maintain said incoming service on said first channel, drop said incoming service or reassign said incoming service to a second channel associated with said base station having an interference value associated therewith within a lower one of said interference bands than said highest available interference band, said determination being based upon said channel quality value and said highest available interference band.

2. The base station of claim 1, wherein said interference values are carrier to interference ratios.

3. The base station of claim 1, wherein said interference values are bit error rates.

4. The base station of claim 1, wherein a highest one of said interference bands is blocked, said highest available interference band being below said highest interference band.

5. The base station of claim 1, further comprising:

categorization logic for categorizing each said channel in accordance with said respective interference values and said associated interference bands; and

a list of said channels categorized using said categorization logic.

6. The base station of claim 1, further comprising:

a second database for storing channel quality categories, said channel quality value being within a select one of said channel quality categories, said decision logic making said determination based upon said select channel quality category.

7. The base station of claim 6, further comprising:

a third database for storing said channel quality categories, said interference bands and rules corresponding with each combination of each of said channel quality categories and each of said interference bands, said determination being a select one of said rules corresponding with said select channel quality category and said highest available interference band.

8. The base station of claim 1, wherein said interference values are measured on uplink channels associated with said base station.

9. The base station of claim 8, wherein said channel quality value is measured on a traffic channel one of said uplink channels associated with said base station.

10. A method for assigning channels to incoming service based upon interefrence measurements and channel quality measurements, comprising the steps of:

measuring interference values on each said channel assigned to a base station within a cellular network;

storing, within a first database within said base station, interference bands based upon said measured interference values;

measuring a channel quality value on a first channel associated with said base station and assigned to a incoming service, said first channel having an interference value associated therewith within a highest available one of said interference bands; and

deciding whether to maintain said incoming service on said first channel, drop said incoming service or reassign said incoming service to a second channel associated with said base station having an interference value associated therewith within a lower one of said interference bands than said highest available interference band, based upon said channel quality value and said highest available interference band.

11. The method of claim 10, further comprising the step of:

blocking a highest one of said interference bands, said highest available interference band being below said highest intereference band.

12. The method of claim 10, further comprising the step of:

categorizing each said channel in accordance with said respective interference values and said associated interference bands.

13. The method of claim 10, further comprising the step of:

storing, within a second database within said base station, channel quality categories, said channel quality value being within a select one of said channel quality categories.

14. The method of claim 13, wherein said step of deciding is based upon said select channel quality category.

15. The method of claim 14, wherein said step of deciding further comprises the steps of:

storing, within a third database within said base station, said channel quality categories, said interference bands and rules corresponding with each combination of each of said channel quality categories and each of said interference bands; and

deciding whether to maintain said incoming service on said first channel, drop said incoming service or re-assign said incoming service to said second channel based upon a select one of said rules corresponding with said select channel quality category and said highest available interference band.

16. The method of claim 10, wherein said step of measuring said interference values further comprises the step of:

measuring said interference values on uplink channels associated with said base station.

17. The method of claim 16, wherein said step of measuring said channel quality value further comprises the step of:

measuring said channel quality value on a traffic channel one of said uplink channels associated with said base station.

18. The method of claim 10, further comprising the steps of:

receiving said incoming service by said base station, said incoming service being a call connection; and

assigning said incoming service, by said base station, to said first channel, said first channel being a traffic channel.