System and method for performance enhancement in heterogeneous wireless access network employing band selective power management

• US 9,363,761 B2
• Filed: 04/04/2012
• Issued: 06/07/2016
• Est. Priority Date: 04/05/2010
• Status: Active Grant

• Current Assignee: Intel Corporation
• Original Assignee: Intel Corporation
• Inventors: Venkatraman, Shankar, Sheikh, Khurram P.
• Primary Examiner(s): West, Lewis
• Assistant Examiner(s): Shiue, Dong-Chang
• Application Number:
  US13/439,658
• Publication Number:
  US 20120196611A1
• Time in Patent Office: 1,525 Days
• US Class Current: 1/1
• CPC Class Codes: H04W 52/143 Downlink power control
• CPC Class Codes: H04W 52/343 taking into account loading or congestion level
• CPC Class Codes: H04W 52/346 distributing total power among users or channels
• CPC Class Codes: H04W 52/42 in systems with time, space, frequency or polarisation diversity

Abstract

A system and method for enhancing the performance in heterogeneous wireless access networks employing a distributed antenna system is disclosed. A control unit comprises a distributed antenna system management server which collects load information from each of the carriers. The control unit further comprises a power management decision engine which determines the optimal downlink transmission power level for the carriers based on the collected load information and a set of parameters related to the power for the carriers. Power levels may decrease to baseline parameters when the load on carriers decreases.

Claims

1. A method for optimizing downlink transmission power of a distributed antenna system comprising a plurality of antenna units, comprising:

collecting individual carrier load information from a multi-carrier base station communicating with each of the plurality of antenna units using a plurality of carriers;

varying a downlink transmission power for at least one carrier of the plurality of carriers to a different value from at least one other carrier based on the collected carrier load information and an individual weighing factor for the at least one carrier of the plurality of carriers, wherein power for the plurality of carriers is redistributed based on the weighing factors for the plurality of carriers to prioritize sharing of power between the plurality of carriers;

optimizing, based on the collected carrier load information, downlink transmission power of a subset of the plurality of antenna units to optimize the downlink transmission power of fewer than all of the plurality of antenna units communicating using the plurality of carriers;

determining a time period during which the at least one carrier has a carrier load that exceeds a predefined carrier load threshold;

comparing the time when the carrier load of the at least one carrier exceeds the predefined carrier load threshold to a temporal hysteresis threshold;

maintaining a change in downlink power transmission level to the at least one carrier when the time that the carrier load exceeds the predefined carrier load is greater than the temporal hysteresis threshold;

determining, based on the collected carrier load information, whether an average capacity of the distributed antenna system has improved compared to a prior average capacity;

in response to determining that the average capacity of the distributed antenna system has improved, increasing the transmission power for the subset of antenna units within the distributed antenna system to optimize the downlink transmission power of the subset of the antenna units; and

in response to determining that the average capacity of the distributed antenna system has failed to improve, reducing the downlink transmission power and terminating optimization of the downlink transmission power of the antenna units.

2. The method for optimizing the downlink transmission power of a distributed antenna system as set out in claim 1, wherein the varying the downlink transmission power further comprises:

determining whether the at least one carrier of the plurality of carriers has a carrier load greater than the predefined carrier threshold; and

,

increasing the downlink transmission power for the carrier having the carrier load greater than the predefined carrier threshold.

3. The method for optimizing the downlink transmission power of a distributed antenna system as set out in claim 2, further comprising:

determining downlink transmission power operating parameters for the plurality of carriers; and

,

determining an available surplus increase of downlink transmission power for the carrier having the carrier load greater than the predefined threshold;

wherein increasing the downlink transmission power for the carrier having the carrier load greater than the predefined threshold further comprises increasing the downlink transmission power by an amount less than or equal to the determined available increase of downlink transmission power.

4. The method for optimizing the downlink transmission power of a distributed antenna system as set out in claim 3, wherein increasing the downlink transmission power further comprises:

determining a total available power level for the plurality of carriers;

determining a proportionality factor based on the downlink transmission power operating parameters and the collected carrier load information; and

determining the product of the total available power level and the proportionality factor.

5. The method for optimizing the downlink transmission power of a distributed antenna system as set out in claim 4, wherein determining the total available power level is based on the downlink transmission power operating parameters and the collected carrier load information.

6. The method for optimizing the downlink transmission power of a distributed antenna system as set out in claim 1, further comprising:

resetting the downlink transmission power to baseline values when the collected carrier load is less than a carrier load threshold.

7. The method for optimizing the downlink transmission power of a distributed antenna system as set out in claim 1, further comprising generating a ranked list of carriers based on the collected carrier load information from a plurality of carriers.

8. The method for optimizing the downlink transmission power of a distributed antenna system as set out in claim 7, wherein varying a downlink transmission power further comprises varying a downlink transmission power for carriers ranked highest in the ranked list of carriers.

19. The method for optimizing the downlink transmission power of a distributed antenna system as set out in claim 1, further comprising:

configuring, for each carrier, a total nominal power budget, a minimum power budget and a maximum power budget dependent on a number of transmit antennas on each antenna unit employed by the carrier.

9. A wireless system, comprising:

a multi-carrier base station receiving from each of a plurality of antenna units of a distributed antenna system multi-carrier communication signals having a plurality of carriers, the multi-carrier base station comprising one or more multi-carrier amplifier systems configured to amplify the multi-carrier communication signals;

one or more antennas coupled to the base station and configured to provide a downlink signal; and

,

a power management control unit configured to;

vary a downlink transmission power for at least one carrier of the plurality of carriers to a different value from at least one other carrier based on the collected carrier load information and an individual weighing factor for the at least one carrier of the plurality of carriers, wherein power for the plurality of carriers is redistributed based on the weighing factors for the plurality of carriers to prioritize sharing of power between the plurality of carriers;

optimize, based on the collected carrier load information, downlink transmission power of a subset of the plurality of antenna units to optimize the downlink transmission power of fewer than all of the plurality of antenna units communicating using the plurality of carriers;

determine a time period during which the at least one carrier has a carrier load exceeds a predefined carrier load threshold;

compare the time when the carrier load of the at least one carrier exceeds the predefined carrier load threshold to a temporal hysteresis threshold;

maintain a change in downlink power transmission level to the at least one carrier when the time that the carrier load exceeds the predefined carrier load is greater than the temporal hysteresis threshold;

determine, based on the collected carrier load information, whether an average capacity of the distributed antenna system has improved compared to a prior average capacity;

in response to determining that the average capacity of the distributed antenna system has improved, increase the transmission power for the subset of antenna units within the distributed antenna system to optimize the downlink transmission power of the subset of the antenna units; and

in response to determining that the average capacity of the distributed antenna system has failed to improve, reduce the downlink transmission power and terminate optimization of the downlink transmission power of the antenna units.

10. The wireless system as set out in claim 9, wherein said power management control unit comprises a load collection means for collecting load information of the plurality of carriers and providing values of downlink transmission power levels to the multi-carrier amplifier systems.

11. The wireless system as set out in claim 10, wherein said load collection means is coupled to a network and collects load information from the network.

12. The wireless system as set out in claim 10, wherein said load collection means is coupled to the multi-carrier base station and collects load information from the multi-carrier base station.

13. The wireless system as set out in claim 10, wherein the control unit further comprises a power management decision engine configured to generate power level control signals to the carriers, wherein the power level control signals are based on the collected load information.

14. A wireless distributed antenna system, comprising:

a multi-carrier base station configured to receive multi-carrier communication signals having a plurality of carriers, the multi-carrier base station comprising one or more multi-carrier amplifier systems configured to amplify the multi-carrier communication signals;

a distributed antenna system having a plurality of separate antenna systems, the distributed antenna system coupled to the multi-carrier base station and configured to provide a downlink signal; and

,

a control unit coupled to the multi-carrier base station and configured to;

collect load information of the plurality of carriers,

provide different values of downlink transmission power to the multi-carrier amplifier systems based on the collected carrier load information and an individual weighing factor each carrier of the plurality of carriers, wherein power for the plurality of carriers is redistributed based on the weighing factors for the plurality of carriers to prioritize sharing of power between the plurality of carriers,

optimize, based on the collected carrier load information, the downlink transmission power to a subset of the plurality of multi-carrier amplifier systems to optimize the downlink transmission power of fewer than all of the plurality of multi-carrier amplifier systems communicating using the plurality of carriers;

determine a time period during which the at least one carrier has a carrier load exceeds a predefined carrier load threshold;

compare the time when the carrier load of the at least one carrier exceeds the predefined carrier load threshold to a temporal hysteresis threshold;

maintain a change in downlink power transmission level to the at least one carrier when the time that the carrier load exceeds the predefined carrier load is greater than the temporal hysteresis threshold;

determine, based on the collected carrier load information, whether an average capacity of the distributed antenna system has improved compared to a prior average capacity;

in response to determining that the average capacity of the distributed antenna system has improved, increase the transmission power for the subset of antenna units within the distributed antenna system to optimize the downlink transmission power of the subset of the antenna units; and

in response to determining that the average capacity of the distributed antenna system has failed to improve, reduce the downlink transmission power and terminate optimization of the downlink transmission power of the antenna units.

15. The wireless system of claim 14, wherein the control unit is further configured to collect the load information from one of:

the multi-carrier base station or a network.

16. The wireless system of claim 14, wherein the control unit further comprises:

a distributed antenna system management server configured to collect load information from the plurality of carriers; and

a power management decision engine configured to generate power level control signals to the carrier.

17. The wireless system of claim 16, wherein the power management decision engine is configured to determine the power level control signals based on the collected load information and downlink power operating parameters.

18. The wireless system of claim 14, further comprising:

a second multi-carrier base station configured to receive second multi-carrier communication signals having a plurality of second carriers, the second multi-carrier base station comprising one or more second amplifiers configured to amplify the second multi-carrier communication signals; and

,

a second distributed antenna system having plurality of second separate antenna systems, the second distributed antenna system coupled to the second multi-carrier base station and configured to provide a second downlink signal;

wherein the control unit is coupled to the second multi-carrier base station and is configured to collect load information from the plurality of second carriers and provide values of downlink transmission power to the plurality of second carriers.