Cellular radio communication system with frequency reuse

• US 20020145988A1
• Filed: 04/04/2001
• Published: 10/10/2002
• Est. Priority Date: 04/04/2001
• Status: Active Grant

• Current Assignee: Telefonaktiebolaget LM Ericsson
• Original Assignee: Telefonaktiebolaget LM Ericsson
• Inventors: Dahlman, Erik, Parkvall, Stefan
• Granted Patent: US 7,227,850 B2
• Time in Patent Office: Days
• US Class Current: 370/335
• CPC Class Codes: H04B 7/2618 using hybrid code-time division multiple access [CDMA-TDMA]
• CPC Class Codes: H04L 5/0021 in which codes are applied as a frequency-domain sequences, e.g. MC-CDMA
• CPC Class Codes: H04L 5/0032 Distributed allocation, i.e. involving a plurality of allocating devices, each making partial allocation
• CPC Class Codes: H04L 5/0073 Allocation arrangements that take into account other cell interferences for intercell interference mitigation or co-ordination in orthogonal multiplex systems H04J11/005
• CPC Class Codes: H04W 16/12 Fixed resource partitioning
• CPC Class Codes: H04W 36/18 for allowing seamless reselection, e.g. soft reselection

Abstract

Different frequency reuse values are associated with different channels, e.g., different types of channels in a cellular communications system. For a high speed downlink shared type of channel, the frequency reuse may be greater than one in order to achieve higher data rates. On the other hand, the frequency reuse may be set to one for other channel types, e.g., dedicated channels including both uplink and downlink dedicated channels. Alternatively, the frequency reuse may also be set greater than one for channels in addition to the downlink shared channel, e.g., one or more dedicated downlink channels, while a frequency reuse of one is deployed for one or more uplink dedicated channels. Using different frequency reuse values reduces inter-cell interference, particularly at cell borders, while still maintaining existing soft handover schemes for dedicated channels if one or more of the channels is a code division multiple access (CDMA) type of channel.

Claims

1. A method for use in cellular communications system having first and second channels, comprising:

associating a first frequency reuse for the first channel, and

associating a second frequency reuse for the second channel,

wherein one of the channels is a code division multiple access (CDMA) channel.

2. The method in claim 1, wherein the first channel includes a first type of channel and the second channel includes a second type of channel.

3. The method in claim 2, wherein the first type of channel is a shared channel and the second type of channel is a dedicated channel.

4. The method in claim 3, wherein the shared channel is a downlink channel and the second type of channel includes a downlink dedicated channel associated with the downlink shared channel.

5. The method in claim 3, wherein the second channel type also includes an uplink dedicated channel, associated with the downlink shared channel.

6. The method in claim 3, wherein the first frequency reuse is greater than the second frequency reuse.

7. The method in claim 6, wherein the second frequency reuse is equal to one.

8. The method in claim 2, wherein the first type of channel is a downlink channel and the second type of channel is an uplink channel.

9. The method in claim 8, wherein the first type of channel includes multiple downlink channels and the second type of channel includes one uplink channel associated with the multiple downlink channels.

10. The method in claim 2, wherein the first type of channel is a channel not configured to use soft handover, and the second type of channel is a channel that is configured to use soft handover.

11. The method in claim 1, wherein the other of the first and second channels is an orthogonal frequency division multiplexing (OFDM) channel.

13. The control node in claim 12, wherein the control node is a radio network controller coupled to one or more base stations.

14. The control node in claim 12, wherein the first channel is not a channel configured to use soft handover, and the second channel is a channel that is configured to use soft handover.

15. The control node in claim 12, wherein the first channel includes a first type of channel and the second channel includes a second type of channel.

16. The control node in claim 15, wherein the first channel type is a shared channel and the second channel type is a dedicated channel.

17. The control node in claim 16, wherein the first frequency reuse is greater than one, and the second frequency reuse is equal to one.

18. The control node in claim 15, wherein the first type of channel is a downlink channel and the second type of channel includes an uplink dedicated channel.

19. The control node in claim 18, wherein the second type of channel includes a downlink dedicated channel.

20. The control node in claim 15, wherein the first type of channel includes a downlink channel and the second type of channel includes an uplink channel.

21. The control node in claim 20, wherein the first type of channel includes multiple downlink channels and the second type of channel includes one uplink channel.

22. The control node in claim 12, wherein the first frequency reuse is greater than the second frequency reuse.

23. The control node in claim 12, wherein the other of the first and second channels is an orthogonal frequency division multiplexing (OFDM) channel.

25. The CDMA cellular communications system according to claim 24, wherein the different types of radio channels include a shared type of channel and a dedicated type of channel.

26. The CDMA cellular communications system according to claim 24, wherein the different types of radio channels include a downlink type of channel and an uplink type of channel.

27. The CDMA cellular communications system according to claim 24,

a memory configured to store frequency reuse values for the different types of channels, and

a controller configured to associate a first frequency reuse with a first channel and a second frequency reuse with a second channel.

28. The CDMA cellular communications system according to claim 24, wherein at least one of the channel types is a CDMA type of channel.

29. The CDMA cellular communications system according to claim 28, wherein the other of the channel types is an orthogonal frequency division multiplexing (OFDM) type of channel.

12. A control node for use in a cellular radio communications system, comprising:

a memory configured to store frequency reuse values for different channels, and

a controller configured to associate a first frequency reuse with a first channel and a second frequency reuse with a second channel

wherein one of the first and second channels is a code division multiple access (CDMA) channel.

24. A code division multiple access (CDMA) cellular communications system using different frequency reuse values for different types of radio channels.

30. A communications node for use in code division multiple access (CDMA) cellular communications system having first and second CDMA channel types, comprising:

means for associating a first frequency reuse for the first CDMA channel type, and

means for associating a second frequency reuse for the second CDMA channel type.

31. The communications node in claim 30, wherein the first type of CDMA channel is a shared channel and the second type of CDMA channel is a dedicated channel.

32. The communications node in claim 31, wherein the shared channel is a downlink channel and the second type of channel includes a downlink dedicated channel.

33. The method in claim 32, wherein the second type of CDMA channel also includes an uplink dedicated channel.

34. The communications node in claim 30, wherein the first type of CDMA channel is a downlink channel and the second type of CDMA channel is an uplink channel.

35. The communications node in claim 34, wherein the first type of CDMA channel includes multiple downlink channels and the second type of CDMA channel includes an uplink channel.