System and method for reducing reverse noise rise in wireless communications

• US 7,936,698 B1
• Filed: 05/13/2008
• Issued: 05/03/2011
• Est. Priority Date: 05/13/2008
• Status: Expired due to Fees

• Current Assignee: Sprint Spectrum LLC (Deutsche Telekom AG)
• Original Assignee: Sprint Spectrum LP (Deutsche Telekom AG)
• Inventors: Sarkar, Debasish, Shetty, Manoj J., Vargantwar, Sachin R.
• Primary Examiner(s): Ferris; Derrick W
• Assistant Examiner(s): KHIRODHAR, MAHARISHI V
• Application Number:
  US12/119,528
• Time in Patent Office: 1,085 Days
• Field of Search: 370/252, 370/332, 370/328, 370/235
• US Class Current: 370/252
• CPC Class Codes: H04B 17/345 Interference values signal-to-interference ratio [SIR] or carrier-to-interference ratio [CIR] H04B17/336

Abstract

A method and system for increasing throughput of a wireless communications network and for reducing a reverse noise rise experienced by the wireless network are described. An access network and/or one or more access terminals monitor an activity level of reverse-link communications occurring between the access network and the access terminal(s). The access network and/or the access terminal(s) make a determination of whether an activity level of the reverse-link communications exceeds a threshold. If the threshold is exceeded, the access network and the access terminal(s) each operate in states such that the access network does not measure a noise floor and the access terminal(s) transmit communications to the access network. If the threshold is not exceeded, the access network and the access terminal(s) each operate in states such that the access network measures the noise floor and the access terminal(s) do not transmit communications to the access network.

Claims

1. A method carried out at an access network, the method comprising:

at the access network, during a given monitoring period, monitoring an activity level of reverse-link communications occurring between the access network and one or more access terminals;

at the access network, making a determination of whether the monitored activity level of reverse-link communications exceeds a threshold;

if the determination is that the monitored activity level of reverse-link communications does not exceed the threshold, then, during a given adjustment period that occurs after the given monitoring period, responsively operating the access network in a first state, wherein operating the access network in the first state includes the access network (i) measuring a noise floor, and (ii) not receiving any communications from the one or more access terminals; and

if the determination is that the monitored activity level of reverse-link communications exceeds the threshold, then, during the given adjustment period, responsively operating the access network in a second state, wherein operating the access network in the second state includes the access network (i) receiving communications from at least one of the one or more access terminals, and (ii) not measuring the noise floor.

2. The method of claim 1, wherein monitoring the activity level of reverse-link communications comprises monitoring one or more reverse activity bits transmitted from the access network to the one or more access terminals.

3. The method of claim 2,

wherein each reverse activity bit of the one or more reverse activity bits has a value that indicates a high level of reverse-link activity or a value that does not indicate a high level of reverse-link activity,

wherein, if each reverse activity bit of the one or more reverse activity bits has a value that indicates a high level of reverse-link activity, then the determination is that the monitored activity level exceeds the threshold, and

wherein, if at least one reverse activity bit of the one or more reverse activity bits has a value that does not indicate a high level of reverse-link activity, then the determination is that the monitored activity level does not exceed the threshold.

4. The method of claim 2,

wherein each reverse activity bit of the one or more reverse activity bits has a value that indicates a high level of reverse-link activity or a value that does not indicate a high level of reverse-link activity,

wherein the threshold comprises a threshold percentage value,

the method further comprising:

calculating a percentage of the one or more reverse activity bits that have a value that indicates a high level of reverse-link activity; and

comparing the calculated percentage of the one or more reverse activity bits that have a value that indicates a high level of reverse-link activity to the threshold percentage value,

wherein, if the calculated percentage is greater than or equal to the threshold percentage value, then the determination is that the monitored activity level exceeds the threshold, and

wherein, if the calculated percentage is less than the threshold percentage value, then the determination is that the monitored activity level does not exceed the threshold.

5. The method of claim 1,

wherein the one or more access terminals comprise (i) one or more access terminals operating a first type of wireless communication application, and (ii) one or more access terminals operating a second type of wireless communication application, and

wherein each of the at least one of the one or more access terminals from which the access network receives communications while the access network operates in the second state comprises one of the access terminals operating the first type of wireless communication application.

6. The method of claim 5,

wherein the first type of wireless communication application comprises a best-effort application, and

wherein the second type of wireless communication application comprises an application selected from the group consisting of (i) a push-to-talk application, and (ii) a Voice over Internet Protocol (VoIP) application.

7. The method of claim 1, wherein the monitoring period occurs over a configurable amount of time.

8. The method of claim 1,

wherein the monitoring period comprises a monitoring period start point and a monitoring period end point,

wherein the monitoring period start point occurs prior to the monitoring period end point,

wherein the given adjustment period comprises an adjustment period start point and an adjustment period end point,

wherein the adjustment period start point occurs prior to the adjustment period end point, and

wherein the monitoring period end point and the adjustment period start point occur at substantially the same time.

9. The method of claim 1,

wherein the monitoring period comprises a monitoring period start point and a monitoring period end point,

wherein the monitoring period start point occurs prior to the monitoring period end point,

wherein the given adjustment period comprises an adjustment period start point and an adjustment period end point,

wherein the adjustment period start point occurs prior to the adjustment period end point, and

wherein after the monitoring period end point and prior to the adjustment period start point, at least one time slot of data is transmitted via the access network.

10. A system comprising:

a communications interface operable to transmit forward-link communications to a given set of one or more access terminals and to receive reverse-link communications from the given set of one or more access terminals;

a processor; and

data storage device storing computer-readable program instructions executable by the processor, wherein the program instructions include instructions that cause the processor to (i) during a given monitoring period, monitor an activity level of reverse-link communications occurring between the communications interface and the given set of one or more access terminals, (ii) make a determination of whether the monitored activity level of reverse-link communications exceeds a threshold, (iii) if the determination is that the monitored activity level of reverse-link communications does not exceed the threshold, then, during a given adjustment period that occurs after the given monitoring period, responsively operate in a first state, wherein while the processor operates in the first state, the processor measures a noise floor, and (iv) if the determination is that the monitored activity level of reverse-link communications exceeds the threshold, then, during the given adjustment period, responsively operate in a second state, wherein while the processor operates in the second state, the processor does not measure the noise floor,

wherein, while the processor operates in the first state, the communications interface does not receive any reverse-link communications from the given set of one or more access terminals, and

wherein, while the processor operates in the second state and during at least a portion of the given adjustment period, the communications interface receives reverse-link communications from the given set of one or more access terminals.

11. The system of claim 10, wherein each access terminal of the given set of one or more access terminals comprises an access terminal that is registered, with the system, as an access terminal authorized to be served by the system.

12. The system of claim 11,

wherein, during the given monitoring period, the communications interface transmits one or more reverse activity bits to the given set of one or more access terminals, and

wherein the program instructions to monitor the activity level of reverse-link communications comprise instructions to monitor the one or more reverse activity bits transmitted, during the given monitoring period, from the communications interface.

13. The system of claim 12,

wherein each reverse activity bit of the one or more reverse activity bits has a value that indicates a high level of reverse-link activity or a value that does not indicate a high level of reverse-link activity,

wherein the program instructions to make the determination of whether the monitored activity level of reverse-link communications exceeds a threshold comprise instructions to determine whether each reverse activity bit of the one or more reverse activity bits has a value that indicates a high level of reverse-link activity,

wherein, if each reverse activity bit of the one or more reverse activity bits has a value that indicates a high level of reverse-link activity, then the determination is that the monitored activity level exceeds the threshold, and

wherein, if at least one reverse activity bit of the one or more reverse activity bits has a value that does not indicate a high level of reverse-link activity, then the determination is that the monitored activity level does not exceed the threshold.

14. The system of claim 12,

wherein each reverse activity bit of the one or more reverse activity bits has a value that indicates a high level of reverse-link activity or a value that does not indicate a high level of reverse-link activity, and

wherein the threshold comprises a threshold percentage value,

wherein the program instructions to make the determination of whether the monitored activity level of reverse-link communications exceeds a threshold comprise instructions to (i) calculate a percentage of the one or more reverse activity bits that have a value that indicates a high level of reverse-link activity, and (ii) compare the calculated percentage of the one or more reverse activity bits that have a value that indicates a high level of reverse-link activity to the threshold percentage value,

wherein, if the calculated percentage is greater than or equal to the threshold percentage value, then the determination is that the monitored activity level exceeds the threshold, and

wherein, if the calculated percentage is less than the threshold percentage value, then the determination is that the monitored activity level does not exceed the threshold.

15. A method carried out at a given access terminal, the method comprising:

at the given access terminal, during a first monitoring period, monitoring a first activity level of reverse-link communications occurring between an access network and one or more access terminals, the one or more access terminals including the given access terminal;

at the given access terminal, making a first determination of whether the first activity level of reverse-link communications exceeds a threshold;

if the first determination is that the first activity level of reverse-link communications does not exceed the threshold, then, during a first adjustment period that occurs after the first monitoring period, responsively operating the given access terminal in a first state, wherein, while the given access terminal operates in the first state, the given access terminal does not transmit communications to the access network and the access network measures a noise floor; and

if the first determination is that the first activity level of reverse-link communications exceeds the threshold, then, during the first adjustment period, responsively operating the given access terminal in a second state, wherein, while the given access terminal operates in the second state, the given access terminal transmits communications to the access network and the access network does not measure the noise floor.

16. The method of claim 15, further comprising:

at the given access terminal, during the monitoring period, receiving one or more reverse activity bits that are transmitted to the given access terminal from the access network,

wherein monitoring the activity level of reverse-link communications comprises monitoring the one or more reverse activity bits.

17. The method of claim 16,

wherein each reverse activity bit of the one or more reverse activity bits has a value that indicates a high level of reverse-link activity or a value that does not indicate a high level of reverse-link activity,

wherein, if each reverse activity bit of the one or more reverse activity bits has a value that indicates a high level of reverse-link activity, then the determination is that the monitored activity level exceeds the threshold, and

wherein, if at least one reverse activity bit of the one or more reverse activity bits has a value that does not indicate a high level of reverse-link activity, then the determination is that the monitored activity level does not exceed the threshold.

18. The method of claim 16,

wherein each reverse activity bit of the one or more reverse activity bits has a value that indicates a high level of reverse-link activity or a value that does not indicate a high level of reverse-link activity, and

wherein the threshold comprises a threshold percentage value,

the method further comprising:

calculating a percentage of the one or more reverse activity bits that have a value that indicates a high level of reverse-link activity; and

comparing the calculated percentage of the one or more reverse activity bits that have a value that indicates a high level of reverse-link activity to the threshold percentage value,

wherein, if the calculated percentage is greater than or equal to the threshold percentage value, then the determination is that the monitored activity level exceeds the threshold, and

wherein, if the calculated percentage is less than the threshold percentage value, then the determination is that the monitored activity level does not exceed the threshold.

19. The method of claim 15,

wherein during the first monitoring period, when making the first determination, and during the first adjustment period, the given access terminal executes a first type of wireless communication application, but does not execute a second type of wireless communication application,

the method further comprising:

at the given access terminal, during a second monitoring period, monitoring a second activity level of reverse-link communications occurring between the given access terminal and the access network;

at the given access terminal, making a second determination of whether the second activity level of reverse-link communications exceeds the threshold;

if the second determination is that the second activity level of reverse-link communications does not exceed the threshold, then, during a second adjustment period that occurs after the second monitoring period, responsively operating the given access terminal in a first state, wherein, while the given access terminal operates in the first state, the given access terminal does not transmit communications to the access network and the access network measures a noise floor; and

if the second determination is that the second activity level of reverse-link communications exceeds the threshold, then, during the second adjustment period, responsively operating the given access terminal in a second state, wherein, while the given access terminal operates in the second state, the given access terminal transmits communications to the access network and the access network does not measure the noise floor.

20. An apparatus comprising:

a communications interface operable to receive forward-link communications from an access network and to transmit reverse-link communications to the access network;

a processor; and

a computer-readable data storage device storing computer-readable program instructions executable by the processor, wherein the program instructions include instructions that (i) cause the processor to, during a given monitoring period, monitor an activity level of reverse-link communications occurring between one or more access terminals and the access network, (ii) cause the processor to make a determination of whether the monitored activity level of reverse-link communications exceeds a threshold, (iii) if the determination is that the monitored activity level of reverse-link communications does not exceed the threshold, then, during a given adjustment period that occurs after the given monitoring period, responsively operate in a first state, wherein while the processor operates in the first state, the communication interface does not transmit reverse-link communications to the access network, and (iv) if the determination is that the monitored activity level of reverse-link communications exceeds the threshold, then, during the given adjustment period, responsively operate in a second state, wherein while the processor operates in the second state, the communications interface transmits reverse-link communications to the access network,

wherein, while the processor operates in the first state and during at least a portion of the given adjustment period, the access network measures a noise floor, and

wherein, while the processor operates in the second state and during the given adjustment period, the access network does not measure the noise floor.