Method and system for assuring near uniform capacity and quality of channels in cells of wireless communications systems having cellular architectures

• US 6,011,970 A
• Filed: 07/23/1997
• Issued: 01/04/2000
• Est. Priority Date: 07/23/1997
• Status: Expired due to Fees

• Current Assignee: Nortel Networks Limited (Nortel Networks Corporation)
• Original Assignee: Nortel Networks Corporation
• Inventors: McCarthy, Michael John
• Primary Examiner(s): Urban, Edward F.
• Assistant Examiner(s): Gesesse, Tilahun
• Application Number:
  US08/899,348
• Time in Patent Office: 895 Days
• Field of Search: 455/436, 455/439, 455/438, 455/63, 455/67.3, 455/513, 370/332, 370/333
• US Class Current: 455/436
• CPC Class Codes: H04W 16/02 Resource partitioning among network components, e.g. reuse partitioning
• CPC Class Codes: H04W 16/12 Fixed resource partitioning

Abstract

A method and system for use with wireless communication systems having a cellular architecture with at least a first and a second cell. The method and system provided ensure near uniform capacity and quality of channels within the second cell via the following steps. The noise signal power in unused data channels within the second cell is monitored. When a request for channel access is received, a determination is made whether the request for channel access is either a request for handoff from the first cell into the second cell, or not. In the event that the request is not a request for handoff, a determination is made whether idle channels exist to satisfy the request for channel access. In the event of a determination either that the request for channel access is a request for handoff, or both that the request is not a request for handoff and that idle channels exist to satisfy the request, a measured received signal power of a mobile unit subscriber unit making the request is determined. One of the unused channels in the second cell is then preferentially assigned to the mobile subscriber unit where such preference in assigning is to assign a channel, provided that a signal to noise ratio calculated upon the monitored received signal power and the monitored noise signal power of the preferentially assigned noisy channel meets or exceeds a required signal to noise ratio.

Claims

1. A method for use with wireless communications systems having a cellular architecture with at least a first and a second cell, said method ensuring near uniform capacity and quality of data channels within said second cell, and said method comprising the steps of:

monitoring a noise signal power in unused data channels within said second cell, wherein said unused data channels are grouped into at least a noisy group of unused data channels and a clear group of unused data channels on the basis of said monitored noise signal power;

monitoring a received signal power of a first mobile subscriber unit engaged in a call-in progress when said call-in-progress is to be handed off from said first cell into said second cell;

comparing said monitored received signal power of said first mobile subscriber unit engaged in a call-in-progress with a first prespecified threshold; and

in response to a handoff request from said first cell, preferentially assigning one of said unused data channels in said second cell to said first mobile subscriber unit where such preference in assigning is to assign a channel such that a signal to noise ratio calculated upon said monitored received signal power and said monitored noise signal power of said preferentially assigned channel meets or exceeds a required signal to noise ratio such that near uniform capacity and quality of data channels within said second cell is ensured, wherein;

said first mobile subscriber unit engaged in a call-in-progress is assigned an unused data channel from said noisy group of unused data channels when said noisy group contains at least one unused data channel and when said first comparing of said monitored received signal power of said first mobile subscriber unit engaged in a call-in-progress indicates said monitored received signal power is greater than said first prespecified threshold; and

said first mobile subscriber unit engaged in a call-in-progress is assigned an unused data channel from said clear group of unused data channels when said clear group contains at least one unused data channel and when said first comparing of said monitored received signal power of said first mobile subscriber unit engaged in a call-in-progress indicates said monitored received signal power is less than said first prespecified threshold.

2. The method of claim 1, wherein said step of monitoring a noise signal power in unused data channels within said second cell further comprises the step of ordering said unused data channels based on said noise signal power to facilitate said grouping.

3. The method of claim 2, wherein said step of ordering further comprises the step of rank ordering said unused data channels from the most noisy to the least noisy on the basis of said monitored noise signal power.

4. The method of claim 3 wherein said step of preferentially assigning further comprises:

calculating one or more signal to noise ratios based upon said monitored received signal power of said first mobile subscriber unit and said rank ordered unused channels; and

assigning said first mobile subscriber unit engaged in a call-in-progress the noisiest channel, within said rank ordered unused channels, whose said calculated signal to noise ratio meets or exceeds a predetermined signal to noise ratio.

5. The method of claim 3 wherein said step of preferentially assigning further comprises:

calculating one or more signal to noise ratios based upon said monitored received signal power of said first mobile subscriber unit and said rank ordered unused channels; and

assigning said first mobile subscriber unit engaged in a call-in-progress a channel, within said rank ordered unused channels, whose said calculated signal to noise ratio meets or exceeds a predetermined signal to noise ratio.

6. The method of claim 3, further comprising the steps of:

in response to a request by a second mobile subscriber unit for access to a channel where said request for access is not a handoff request, determining whether a number of unused data channels within said second cell has fallen below a prespecified number of channels that have been reserved for handoff;

in response to a determination that said number of unused data channels within said second cell has not fallen below said prespecified number of channels reserved for handoff;

monitoring a received signal power of said second mobile subscriber unit making said request for access to said channel within said second cell; and

preferentially assigning one of said unused data channels in said second cell to said second mobile subscriber unit where such preference in assigning is to assign a channel such that a signal to noise ratio calculated upon said monitored received signal power and said monitored noise signal power of said preferentially assigned channel meets or exceeds a required signal to noise ratio such that near uniform capacity and quality of data channels within said second cell is ensured.

7. The method of claim 6 wherein said step of preferentially assigning further comprises:

calculating one or more signal to noise ratios based upon said monitored received signal power of said second mobile subscriber unit and said rank ordered unused channels; and

assigning said second mobile subscriber unit engaged in a call-in-progress the noisiest channel, within said rank ordered unused channels, whose said calculated signal to noise ratio meets or exceeds a predetermined signal to noise ratio.

8. The method of claim 6 wherein said step of preferentially assigning further comprises:

calculating one or more signal to noise ratios based upon said monitored received signal power of said second mobile subscriber unit and said rank ordered unused channels; and

assigning said second mobile subscriber unit engaged in a call-in-progress a channel, within said rank ordered unused channels, whose said calculated signal to noise ratio meets or exceeds a predetermined signal to noise ratio.

9. The method claim 1, further comprising the steps of:

a second comparing of said monitored received signal power of said first mobile subscriber unit engaged in a call-in-progress with a second prespecified threshold when said first comparing of said monitored received signal power of said first mobile subscriber unit engaged in a call-in-progress indicates said monitored received signal power is less than or equal to said first prespecified threshold;

assigning said first mobile subscriber unit engaged in a call-in-progress an unused data channel from said clear group of unused data channels when said clear group contains at least one unused data channel and when said second comparing of said monitored received signal power of said first mobile subscriber unit engaged in a call-in-progress with a second prespecified threshold indicates that said monitored received signal power of said first mobile subscriber unit engaged in a call-in-progress is greater than or equal to said second prespecified threshold; and

assigning said first mobile subscriber unit engaged in a call-in-progress an unused data channel from said noisy group of unused data channels when said clear group is empty and when said second comparing of said monitored received signal power of said first mobile subscriber unit engaged in a call-in-progress with a second prespecified threshold indicates that said monitored received signal power of said first mobile subscriber unit engaged in a call-in-progress is greater than or equal to said second prespecified threshold.

10. The method of claim 1, further comprising the steps of:

in response to a request by a second mobile subscriber unit for access to a channel where said request for access is not a handoff request, determining whether a number of unused data channels within said second cell has fallen below a prespecified number of channels that have been reserved for handoff;

in response to a determination that said number of unused data channels within said second cell has not fallen below and prespecified number of channels reserved for handoff;

monitoring a received signal power of said second mobile subscriber unit making said request for access to said channel within said second cell; and

preferentially assigning one of said unused data channels in said second cell to said second mobile subscriber unit where such preference in assigning is to assign a channel such that a signal to noise ratio calculated upon said monitored received signal power and said monitored noise signal power of said preferentially assigned channel meets or exceeds a required signal to noise ratio such that near uniform capacity and quality of data channels within said second cell is ensured.

11. The method of claim 10 wherein said step of preferentially assigning further comprises the steps of:

a first comparing of said monitored received signal power of said second mobile subscriber unit making said request for access with a first prespecified threshold;

assigning said second mobile subscriber unit making said request for access an unused data channel from said noisy group of unused data channels when said noisy group contains at least one unused data channel and when said first comparing of said monitored received signal power of said second mobile subscriber unit making said request for access indicates said monitored received signal power is greater than said first prespecified threshold; and

assigning said second mobile subscriber unit making said request for access an unused data channel from said clear group of unused data channels when said noisy group is empty and when said first comparing of said monitored received signal power of said second mobile subscriber unit making said request for access indicates said monitored received signal power is greater than said first prespecified threshold.

12. The method of claim 11, further comprising the steps of:

a second comparing of said monitored received signal power of said second mobile subscriber unit making said request for access with a second prespecified threshold when said first comparing of said monitored received signal power of said second mobile subscriber unit making said request for access indicates said monitored received signal power is greater than said first prespecified threshold;

assigning said second mobile subscriber unit making said request for access an unused data channel from said clear group of unused data channels when said clear group contains at least one unused data channel and when said second comparing of said monitored received signal power of said second mobile subscriber unit making said request for access with a second prespecified threshold indicates that said monitored received signal power of said second mobile subscriber unit making said request for access is greater than or equal to said second prespecified threshold; and

assigning said second mobile subscriber unit making said request for access an unused data channel from said noisy group of unused data channels when said clear group is empty and when said second comparing of said monitored received signal power of said second mobile subscriber unit making said request for access with a second prespecified threshold indicates that said monitored received signal power of said second mobile subscriber unit making said request for access is greater than or equal to said second prespecified threshold.

13. An apparatus for use with wireless communications systems having a cellular architecture with at least a first and a second cell, said apparatus ensuring near uniform capacity and quality of data channels within said second cell, and said apparatus comprising:

means for monitoring a noise signal power in unused data channels within said second cell, wherein said unused data channels are grouped into at least a noisy group of unused data channels and a clear group of unused data channels on the basis of said monitored noise signal power;

means for monitoring a received signal power of a first mobile subscriber unit engaged in a call-in progress when said call-in-progress is to be handed off from said first cell into said second cell;

means for comparing said monitored received signal power of said first mobile subscriber unit engaged in a call-in-progress with a first prespecified threshold; and

means, responsive to a handoff request from said first cell, for preferentially assigning one of said unused data channels in said second cell to said first mobile subscriber unit where such preference in assigning is to assign a channel such that a signal to noise ratio calculated upon said monitored received signal power and said monitored noise signal power of said preferentially assigned channel meets or exceeds a required signal to noise ratio such that near uniform capacity and quality of data channels within said second cell is ensured, wherein;

said first mobile subscriber unit engaged in a call-in-progress is assigned an unused data channel from said noisy group of unused data channels when said noisy group contains at least one unused data channel and when said first comparing of said monitored received signal power of said first mobile subscriber unit engaged in a call-in-progress indicates said monitored received signal power is greater than said first prespecified threshold; and

said first mobile subscriber unit engaged in a call-in-progress is assigned an unused data channel from said clear group of unused data channels when said clear group contains at least one data channel and when said first comparing of said monitored received signal power of said first mobile subscriber unit engaged in a call-in-progress indicates said monitored received signal power is less than said first prespecified threshold.

14. The apparatus of claim 13, wherein said means for monitoring a noise signal power in unused data channels within said second cell further comprises means for ordering said unused data channels based on said noise signal power to facilitate said grouping.

15. The apparatus of claim 14, wherein said means for ordering further comprises means for rank ordering said unused data channels from the most noisy to the least noisy on the basis of said monitored noise signal power.

16. The apparatus of claim 15, wherein said means for preferentially assigning further comprises:

means for calculating one or more signal to noise ratios based upon said monitored received signal power of said first mobile subscriber unit and said rank ordered unused channels; and

means for assigning said first mobile subscriber unit engaged in a call-in-progress the noisiest channel, within said rank ordered unused channels, whose said calculated signal to noise ratio meets or exceeds a predetermined signal to noise ratio.

17. The apparatus of claim 15 wherein said means for preferentially assigning further comprises:

means for calculating one or more signal to noise ratios based upon said monitored received signal power of said first mobile subscriber unit and said rank ordered unused channels; and

means for assigning said first mobile subscriber unit engaged in a call-in-progress a channel, within said rank ordered unused channels, whose said calculated signal to noise ratio meets or exceeds a predetermined signal to noise ratio.

18. The apparatus of claim 17, further comprising:

means, responsive to a request by a second mobile subscriber unit for access to a channel where said request for access is not a handoff request, for determining whether a number of unused data channels within said second cell has fallen below a prespecified number of channels that have been reserved for handoff;

means, responsive to a determination that said number of unused data channels within said second cell has not fallen below said prespecified number of channels reserved for handoff, comprising;

means for monitoring a received signal power of said second mobile subscriber unit making said request for access to said channel within said second cell; and

means for preferentially assigning one of said unused data channels in said second cell to said second mobile subscriber unit where such preference in assigning is to assign a channel such that a signal to noise ratio calculated upon said monitored received signal power and said monitored noise signal power of said preferentially assigned channel meets or exceeds a required signal to noise ratio such that near uniform capacity and quality of data channels within said second cell is ensured.

19. The apparatus of claim 18 wherein said means for preferentially assigning further comprises:

means for calculating one or more signal to noise ratios based upon said monitored received signal power of said second mobile subscriber unit and said rank ordered unused channels; and

means for assigning said second mobile subscriber unit engaged in a call-in-progress the noisiest channel, within said rank ordered unused channels, whose said calculated signal to noise ratio meets or exceeds a predetermined signal to noise ratio.

20. The apparatus of claim 18 wherein said means for preferentially assigning further comprises:

means for calculating one or more signal to noise ratios based upon said monitored received signal power of said second mobile subscriber unit and said rank ordered unused channels; and

means for assigning said second mobile subscriber unit engaged in a call-in-progress a channel, within said rank ordered unused channels, whose said calculated signal to noise ratio meets or exceeds a predetermined signal to noise ratio.

21. The apparatus of claim 13, further comprising:

means for making a second comparing of said monitored received signal power of said first mobile subscriber unit engaged in a call-in-progress with a second prespecified threshold when said first comparing of said monitored received signal power of said first mobile subscriber unit engaged in a call-in-progress indicates said monitored received signal power is less than or equal to said first prespecified threshold;

means for assigning said first mobile subscriber unit engaged in a call-in-progress an unused data channel from said clear group of unused data channels when said clear group contains at least one unused data channel and when said second comparing of said monitored received signal power of said first mobile subscriber unit engaged in a call-in-progress with a second prespecified threshold indicates that said monitored received signal power of said first mobile subscriber unit engaged in a call-in-progress is greater than or equal to said second prespecified threshold; and

means for assigning said first mobile subscriber unit engaged in a call-in-progress an unused data channel from said noisy group of unused data channels when said clear group is empty and when said second comparing of said monitored received signal power of said first mobile subscriber unit engaged in a call-in-progress with a second prespecified threshold indicates that said monitored received signal power of said first mobile subscriber unit engaged in a call-in-progress is greater than or equal to said second prespecified threshold.

22. The apparatus of claim 13, further comprising:

means, responsive to a request by a second mobile subscriber unit for access to a channel where said request for access is not a handoff request, for determining whether a number of unused data channels within said second cell has fallen below a prespecified number of channels that have been reserved for handoff;

means, responsive to a determination that said number of unused data channels within said second cell has not fallen below said prespecified number of channels reserved for handoff, comprising;

means for monitoring a received signal power of a second mobile subscriber unit making said request for access to said channel within said second cell;

means for preferentially assigning one of said unused data channels in said second cell to said second mobile subscriber unit where such preference in assigning is to assign a channel such that a signal to noise ratio calculated upon said monitored received signal power and said monitored noise signal power of said preferentially assigned channel meets or exceeds a required signal to noise ratio such that near uniform capacity and quality of data channels within said second cell is ensured.

23. The apparatus of claim 22, wherein said means for preferentially assigning further comprises:

means for making a first comparing of said monitored received signal power of said second mobile subscriber unit making said request for access with a first prespecified threshold;

means for assigning said second mobile subscriber unit making said request for access an unused data channel from said noisy group of unused data channels when said noisy group contains at least one unused data channel and when said first comparing of said monitored received signal power of said second mobile subscriber unit making said request for access indicates said monitored received signal power is greater than said first prespecified threshold; and

means for assigning said second mobile subscriber unit making said request for access an unused data channel from said clear group of unused data channels when said noisy group is empty and when said first comparing of said monitored received signal power of said second mobile subscriber unit making said request for access indicates said monitored received signal power is greater than said first prespecified threshold.

24. The apparatus of claim 23, further comprising:

means for making a second comparing of said monitored received signal power of said second mobile subscriber unit making said request for access with a second prespecified threshold when said first comparing of said monitored received signal power of said second mobile subscriber unit making said request for access indicates said monitored received signal power is greater than said first prespecified threshold;

means for assigning said second mobile subscriber unit making said request for access an unused data channel from said clear group of unused data channels when said second comparing of said monitored received signal power of said second mobile subscriber unit making said request for access with a second prespecified threshold indicates that said monitored received signal power of said second mobile subscriber unit making said request for access is less than said second prespecified threshold;

means for assigning said second mobile subscriber unit making said request for access an unused data channel from said clear group of unused data channels when said clear group contains at least one unused data channel and when said second comparing of said monitored received signal power of said second mobile subscriber unit making said request for access with a second prespecified threshold indicates that said monitored received signal power of said second mobile subscriber unit making said request for access is greater than or equal to said second prespecified threshold; and

means for assigning said second mobile subscriber unit making said request for access an unused data channel from said noisy group of unused data channels when said clear group is empty and when said second comparing of said monitored received signal power of said second mobile subscriber unit making said request for access with a second prespecified threshold indicates that said monitored received signal power of said second mobile subscriber unit making said request for access is greater than or equal to said second prespecified threshold.