System, method and apparatus for facilitating resource allocation in a communication system

• US 20020160781A1
• Filed: 02/23/2001
• Published: 10/31/2002
• Est. Priority Date: 02/23/2001
• Status: Abandoned Application

• Current Assignee: Telefonaktiebolaget LM Ericsson
• Original Assignee: Telefonaktiebolaget LM Ericsson
• Inventors: Wiberg, Niclas, Bark, Gunnar, Helmersson, Ke Wang
• Application Number:
  US09/791,987
• Publication Number:
  US 20020160781A1
• Time in Patent Office: Days
• US Class Current: 455/450
• CPC Class Codes: H04W 52/16 Deriving transmission power values from another channel
• CPC Class Codes: H04W 52/24 using SIR [Signal to Interference Ratio] or other wireless path parameters
• CPC Class Codes: H04W 52/325 Power control of control or pilot channels
• CPC Class Codes: H04W 72/542 using measured or perceived quality

Abstract

A system, method, and apparatus for the efficient allocation of dedicated and/or shared downlink communication channels for packet data users in a communication system. The present invention provides a switching scheme in which users which are close to a base station are allocated a downlink shared channel in order to save channelization codes in the system, whereas users that are far from a base station are allocated a downlink dedicated channel in order to conserve transmission power.

Claims

1. A system for allocating radio resources in a communication system, said system comprising:

a base station providing a downlink shared channel and a downlink dedicated channel;

a user terminal in communication with said base station, said user terminal being allocated one of said downlink shared channel and said downlink dedicated channel; and

a switching means for switching said user terminal between said downlink shared channel and said downlink dedicated channel based upon a signal threshold.

2. The system of claim 1, wherein said signal threshold is a distance measurement.

3. The system of claim 2, wherein said distance measurement is selected from the group consisting of a link quality to a serving cell, a link quality to a second best cell, a downlink shared channel power associated with said user terminal, and an expected downlink shared channel power associated with said user terminal.

4. The system of claim 1, wherein said signal threshold is a downlink path loss measurement from said user terminal.

5. The system of claim 1, wherein said system is a wideband code division multiple access (WCDMA) system.

6. The system of claim 1, wherein said base station comprises a Node B component.

7. The system of claim 1, said system further comprising:

a base station controller in communication with said base station; and

a core network in communication with said base station controller.

8. The system of claim 7, wherein said core network is selected from the group consisting of a public switched telephone network (PSTN) and a wireless communication network.

9. The system of claim 7, wherein said base station controller is a radio network controller (RNC).

10. A method for switching a user from a downlink shared channel to a downlink dedicated channel in a communication system, said method comprising the steps of:

(a) determining the availability of dedicated channel codes within said communication system;

(b) determining a link quality within said communication system;

(c) determining a downlink shared channel power associated with said user;

(d) switching said user from said downlink shared channel to said downlink dedicated channel if said dedicated channel codes in step (a) are available and said link quality within said communication system in step (b) is less than a first threshold; and

(e) switching said user from said downlink shared channel to said downlink dedicated channel if said dedicated channel codes in step (a) are available and said downlink shared channel power associated with said user in step (c) is greater than a second threshold.

11. The method of claim 10, said step of determining a link quality within said communication system further comprising the step of:

determining a differential between a link quality to a serving cell and a link quality to a second best cell.

12. The method of claim 10, wherein said link quality is a power-to-interference ratio.

13. The method of claim 10, said step of determining a downlink shared channel power associated with said user further comprising the steps of:

estimating the power of an associated downlink dedicated physical control channel (DPCCH); and

adding an offset value associated with a difference in transmitted power between said associated downlink dedicated physical control channel (DPCCH) at a desired quality and said downlink shared channel at a desired quality.

14. The method of claim 13, wherein said step of estimating the power of said associated downlink dedicated physical control channel (DPCCH) is performed in a base station.

15. The method of claim 14, wherein said base station comprises a Node B component.

16. The method of claim 10, wherein said first threshold is a desired cell differential switching level.

17. The method of claim 10, wherein said second threshold is a desired dedicated shared channel power switching level.

19. The method of claim 18, said step of determining a link quality within said communication system further comprising the step of:

determining a differential between a link quality to a serving cell and a link quality to a second best cell.

20. The method of claim 18, wherein said link quality is a power-to-interference ratio.

21. The method of claim 18, said step of determining an expected downlink shared channel power associated with said user further comprising the steps of:

estimating a current value of a downlink dedicated channel power; and

adding an offset value associated with a difference in transmitted power between an associated downlink dedicated physical control channel (DPCCH) at a desired quality and said downlink shared channel at a desired quality.

22. The method of claim 21, wherein said step of estimating a current value of a downlink dedicated channel power is performed in a base station.

23. The method of claim 22, wherein said base station comprises a Node B component.

24. The method of claim 18, wherein said first threshold is a desired cell differential switching level.

25. The method of claim 18, wherein said second threshold is a desired dedicated shared channel power switching level.

27. The method of claim 26, wherein said first channel is a downlink dedicated channel and said second channel is a downlink shared channel.

28. The method of claim 26, wherein said first channel is a downlink shared channel and said second channel is a downlink dedicated channel.

29. The method of claim 26,wherein said communication system is a wideband code division multiple access (WCDMA) system.

18. A method for switching a user from a downlink dedicated channel to a downlink shared channel in a communication system, said method comprising the steps of:

(a) determining a potential of a channel code shortage within said communication system;

(b) determining a link quality within said communication system;

(c) determining an expected downlink shared channel power associated with said user;

(d) switching said user from said downlink dedicated channel to said downlink shared channel if said potential of a channel code shortage within said system in step (a) is present; and

(e) switching said user from said downlink dedicated channel to said downlink shared channel if said link quality within said communication system in step (b) is greater than a first threshold, and said expected downlink shared channel power associated with said user in step (c) is less than a second threshold.

26. A method for switching a user from a first channel to a second channel in a communication system, said method comprising the steps of:

(a) determining a channel code availability criteria within said communication system;

(b) determining a link quality criteria within said communication system;

(c) determining a channel power criteria associated with said user; and

(d) switching said user from said first channel to said second channel based upon said channel code availability criteria, said link quality criteria, and said channel power criteria.

30. A base transceiver apparatus for allocating downlink channels to a user terminal, said base transceiver apparatus comprising:

a base station for providing a downlink shared channel and a downlink dedicated channel;

an allocation means for allocating one of said downlink shared channel and said downlink dedicated channel to said user terminal; and

a switching means for switching said user terminal between said downlink shared channel and said downlink dedicated channel based upon a signal threshold.

31. The base transceiver apparatus of claim 30, wherein said signal threshold is a distance measurement.

32. The base transceiver apparatus of claim 31, wherein said distance measurement is selected from the group consisting of a link quality to a serving cell, a link quality to a second best cell, a downlink shared channel power associated with said user terminal, and an expected downlink shared channel power associated with said user terminal.

33. The system of claim 30, wherein said signal threshold is a downlink path loss measurement from said user terminal.

34. The system of claim 30, wherein said base transceiver apparatus is a wideband code division multiple access (WCDMA) Node B component.