FLEXIBLE SPECTRUM SUPPORT IN CELLULAR WIRELESS COMMUNICATIONS

• US 20140126498A1
• Filed: 11/01/2013
• Published: 05/08/2014
• Est. Priority Date: 11/02/2012
• Status: Active Grant

• Current Assignee: Telefonaktiebolaget LM Ericsson
• Original Assignee: Telefonaktiebolaget LM Ericsson
• Inventors: Koorapaty, Havish, Bergljung, Christian, Cheng, Jung-Fu, Larsson, Daniel
• Granted Patent: US 9,479,321 B2
• Time in Patent Office: Days
• US Class Current: 370/329
• CPC Class Codes: H04L 5/0048 Allocation of pilot signals, i.e. of signals known to the receiver
• CPC Class Codes: H04L 5/0098 Signalling of the activation or deactivation of component carriers, subcarriers or frequency bands
• CPC Class Codes: H04W 16/14 Spectrum sharing arrangements between different networks
• CPC Class Codes: H04W 72/00 Local resource management
• CPC Class Codes: H04W 72/0453 Resources in frequency domain, e.g. a carrier in FDMA

Abstract

Systems and methods for flexible spectrum, or bandwidth, support in a cellular communications network are disclosed. In one embodiment, a base station for a cellular communications network is configured to transmit a non-standardized bandwidth carrier and information that identifies a standardized bandwidth and additional information that, together with the information that identifies the standardized bandwidth, defines a non-standardized bandwidth of the non-standardized bandwidth carrier. In one embodiment, the additional information defines a bandwidth adjustment for the standardized bandwidth that defines the non-standardized bandwidth. In one embodiment, the bandwidth adjustment is a symmetric bandwidth restriction. In another embodiment, the bandwidth adjustment is an asymmetric bandwidth restriction. In yet another embodiment, the bandwidth adjustment is a symmetric bandwidth expansion. In yet another embodiment, the bandwidth adjustment is an asymmetric bandwidth expansion.

Claims

1. A base station for a cellular communications network, comprising:

a radio subsystem; and

a processing subsystem associated with the radio subsystem and configured to transmit, via the radio subsystem, a non-standardized bandwidth carrier and information that identifies a standardized bandwidth and additional information that, together with the information that identifies the standardized bandwidth, defines a non-standardized bandwidth of the non-standardized bandwidth carrier.

2. The base station of claim 1 wherein the standardized bandwidth is greater than the non-standardized bandwidth, and the additional information is information that restricts use of frequency resources of the standardized bandwidth to provide the non-standardized bandwidth.

3. The base station of claim 1 wherein the standardized bandwidth is less than the non-standardized bandwidth, and the additional information is information that expands frequency resources of the standardized bandwidth to provide the non-standardized bandwidth.

4. The base station of claim 1 wherein the additional information defines a symmetric bandwidth adjustment of the standardized bandwidth to provide the non-standardized bandwidth.

5. The base station of claim 4 wherein the standardized bandwidth is greater than the non-standardized bandwidth, and the symmetric bandwidth adjustment is a symmetric restriction of frequency resources at both an upper edge and a lower edge of the standardized bandwidth.

6. The base station of claim 4 wherein the standardized bandwidth is less than the non-standardized bandwidth, and the symmetric bandwidth adjustment is a symmetric expansion of frequency resources at both an upper edge and a lower edge of the standardized bandwidth.

7. The base station of claim 4 wherein synchronization signals and a system broadcast channel are transmitted on frequency resources at a center of the non-standardized bandwidth carrier.

8. The base station of claim 4 wherein the cellular communications network is a Long Term Evolution, LTE, cellular communications network, and primary and secondary synchronization signals and a Physical Broadcast Channel, PBCH, are transmitted on frequency resources at a center of the non-standardized bandwidth carrier.

9. The base station of claim 8 wherein Channel State Information Reference Symbols, CSI-RS, span a full bandwidth of the non-standardized bandwidth carrier.

10. The base station of claim 1 wherein the additional information defines an asymmetric bandwidth adjustment of the standardized bandwidth to provide the non-standardized bandwidth.

11. The base station of claim 10 wherein the standardized bandwidth is greater than the non-standardized bandwidth, and the asymmetric bandwidth adjustment is an asymmetric restriction of frequency resources at an upper edge and a lower edge of the standardized bandwidth.

12. The base station of claim 10 wherein the standardized bandwidth is greater than the non-standardized bandwidth, and the asymmetric bandwidth adjustment is an asymmetric expansion of frequency resources at an upper edge and a lower edge of the standardized bandwidth.

13. The base station of claim 10 wherein synchronization signals and a system broadcast channel are transmitted on frequency resources offset from a center of the non-standardized bandwidth carrier.

14. The base station of claim 10 wherein the cellular communications network is a Long Term Evolution, LTE, cellular communications network, and primary and secondary synchronization signals and a Physical Broadcast Channel, PBCH, are transmitted on frequency resources offset from a center of the non-standardized bandwidth carrier.

15. The base station of claim 10 wherein synchronization signals and a system broadcast channel are transmitted on frequency resources at a center of the standardized bandwidth.

16. The base station of claim 10 wherein the cellular communications network is a Long Term Evolution, LTE, cellular communications network, and primary and secondary synchronization signals and a Physical Broadcast Channel, PBCH, are transmitted on frequency resources at a center of the standardized bandwidth.

17. The base station of claim 16 wherein the asymmetric bandwidth adjustment is selected such that the frequency resources on which the primary and the secondary synchronization signals and the PBCH are transmitted are different than frequency resources on which primary and secondary synchronization signals and PBCH are transmitted in one or more neighboring cells.

18. The base station of claim 1 wherein the processing subsystem is further configured to transmit, via the radio subsystem, a standardized bandwidth carrier in addition to the non-standardized bandwidth carrier.

19. The base station of claim 18 wherein the non-standardized bandwidth carrier is a stand-alone carrier.

20. The base station of claim 19 wherein the cellular communications network is a Long Term Evolution, LTE, cellular communications network, and each of the standardized bandwidth carrier and the non-standardized bandwidth carrier comprises a primary synchronization signal, a secondary synchronization signal, and a Physical Broadcast Control Channel, PBCH.

21. The base station of claim 18 wherein the non-standardized bandwidth carrier is not a stand-alone carrier.

22. The base station of claim 21 wherein the processing subsystem is further configured to transmit the information that identifies the standardized bandwidth and the additional information that defines the non-standardized bandwidth of the non-standardized bandwidth carrier on the standardized bandwidth carrier.

23. The base station of claim 22 wherein the cellular communications network is a Long Term Evolution, LTE, cellular communications network, and the standardized bandwidth carrier signal comprises a primary synchronization signal, a secondary synchronization signal, and a Physical Broadcast Control Channel, PBCH, but the non-standardized bandwidth carrier does not comprise a primary synchronization signal, a secondary synchronization signal, and a PBCH.

24. The base station of claim 21 wherein the non-standardized bandwidth carrier and the standardized bandwidth carrier are synchronized.

25. The base station of claim 1 wherein the non-standardized bandwidth carrier is such that a wireless device that supports only a standardized bandwidth carrier is enabled to access a section of the non-standardized bandwidth carrier corresponding to a standardized bandwidth as a standardized bandwidth carrier.

26. The base station of claim 25 wherein the processing subsystem is further configured to transmit a Master Information Block, MIB, on the non-standardized bandwidth carrier, wherein the MIB includes information that identifies the standardized bandwidth as a standardized bandwidth that is less than the non-standardized bandwidth of the non-standardized bandwidth carrier such that, to the wireless device, the non-standardized bandwidth carrier appears as a standardized bandwidth carrier having the standardized bandwidth.

27. The base station of claim 26 wherein the non-standardized bandwidth carrier comprises a primary synchronization signal, a secondary synchronization signal, and the MIB located in frequency resources at a center of the standardized bandwidth.

28. The base station of claim 27 wherein a bandwidth of an enhanced Physical Downlink Control Channel, EPDCCH, common search space for the non-standardized bandwidth carrier is less than or equal to the standardized bandwidth.

29. The base station of claim 1 wherein the information that identifies the standardized bandwidth is included in one of a group consisting of:

a Master Information Block, MIB, transmitted on the non-standardized bandwidth carrier or a System Information Block, SIB, transmitted on the non-standardized bandwidth carrier.

30. The base station of claim 1 wherein the information that identifies the standardized bandwidth is encoded in at least one of a group consisting of:

a primary synchronization signal transmitted on the non-standardized bandwidth carrier and a secondary synchronization signal transmitted on the non-standardized bandwidth carrier.

31. The base station of claim 1 wherein the additional information that defines the non-standardized bandwidth of the non-standardized bandwidth carrier is included in one of a group consisting of:

a Master Information Block, MIB, transmitted on the non-standardized bandwidth carrier or a System Information Block, SIB, transmitted on the non-standardized bandwidth carrier.

32. The base station of claim 1 wherein the information that defines the non-standardized bandwidth of the non-standardized bandwidth carrier is encoded in a signal transmitted on the non-standardized bandwidth carrier.

33. The base station of claim 1 wherein the information that defines the non-standardized bandwidth of the non-standardized bandwidth carrier is transmitted to one or more wireless devices via Radio Resource Control, RRC, signaling.

34. The base station of claim 1 wherein the information that identifies the standardized bandwidth and the additional information that defines the non-standardized bandwidth of the non-standardized bandwidth carrier are included in a Master Information Block, MIB, transmitted on the non-standardized bandwidth carrier.

35. The base station of claim 34 wherein the MIB comprises a system bandwidth field that includes the information that identifies the standardized bandwidth and a bandwidth adjustment field that includes the additional information, wherein the additional information is information that defines an adjustment to the standardized bandwidth that provides the non-standardized bandwidth.

36. The base station of claim 1 wherein the processing subsystem is further configured to change the non-standardized bandwidth of the non-standardized bandwidth carrier to a new non-standardized bandwidth, wherein changing the non-standardized bandwidth of the non-standardized bandwidth carrier comprises updating at least one of the information that identifies the standardized bandwidth and the additional information to define the new non-standardized bandwidth of the non-standardized bandwidth carrier.

37. A method of operation of a base station in a cellular communications network, comprising:

transmitting a non-standardized bandwidth carrier and information that identifies a standardized bandwidth and additional information that, together with the information that identifies the standardized bandwidth, defines a non-standardized bandwidth of the non-standardized bandwidth carrier.

38. A wireless device for operation in a cellular communications network, comprising:

a radio subsystem; and

a processing subsystem associated with the radio subsystem and configured to;

obtain information that identifies a standardized bandwidth and additional information that, together with the information that identifies the standardized bandwidth, defines a non-standardized bandwidth of a non-standardized bandwidth carrier transmitted by a base station of the cellular communications network; and

receive, via the radio subsystem, the non-standardized bandwidth carrier.

39. The wireless device of claim 38 wherein the standardized bandwidth is greater than the non-standardized bandwidth, and the additional information is information that restricts use of frequency resources of the standardized bandwidth to provide the non-standardized bandwidth.

40. The wireless device of claim 38 wherein the standardized bandwidth is less than the non-standardized bandwidth, and the additional information is information that expands frequency resources of the standardized bandwidth to provide the non-standardized bandwidth.

41. The wireless device of claim 38 wherein the additional information defines a symmetric bandwidth adjustment of the standardized bandwidth to provide the non-standardized bandwidth.

42. The wireless device of claim 38 wherein the additional information defines an asymmetric bandwidth adjustment of the standardized bandwidth to provide the non-standardized bandwidth.

43. The wireless device of claim 38 wherein the processing subsystem is further configured to receive, via the radio subsystem, a standardized bandwidth carrier in addition to the non-standardized bandwidth carrier.

44. A method of operation of a wireless device in a cellular communications network, comprising:

obtaining information that identifies a standardized bandwidth and additional information that, together with the information that identifies the standardized bandwidth, defines a non-standardized bandwidth of a non-standardized bandwidth carrier transmitted by a base station of the cellular communications network; and

receiving the non-standardized bandwidth carrier.

45. A base station for a cellular communications network, comprising:

a radio subsystem; and

a processing subsystem associated with the radio subsystem and configured to;

receive a random access transmission from a wireless device via the radio subsystem, the random access transmission comprising information that is indicative of non-standardized bandwidth capabilities of the wireless device;

select a system bandwidth for the wireless device based on the non-standardized bandwidth capabilities of the wireless device; and

transmit control information to the wireless device via the radio subsystem, the control information being indicative of the system bandwidth selected for the wireless device; and

transmit a carrier via the radio subsystem such that the carrier appears to the wireless device to have a bandwidth equal to the system bandwidth selected for the wireless device.

46. The base station of claim 45 wherein the processing subsystem is further configured to:

receive a random access transmission from a second wireless device via the radio subsystem, the random access transmission comprising information that is indicative of non-standardized bandwidth capabilities of the second wireless device;

select a system bandwidth for the second wireless device based on the non-standardized bandwidth capabilities of the second wireless device, the system bandwidth selected for the second wireless device being different than the system bandwidth selected for the wireless device; and

transmit control information to the second wireless device via the radio subsystem, the control information being indicative of the system bandwidth selected for the second wireless device; and

transmit the carrier such that the carrier appears to the wireless device to have a bandwidth equal to the system bandwidth selected for the wireless device and appears to the second wireless device to have a bandwidth equal to the system bandwidth selected for the second wireless device.

47. The base station of claim 46 wherein the system bandwidth selected for the wireless device is a non-standardized bandwidth such that the carrier appears to the wireless device as a non-standardized bandwidth carrier, and the system bandwidth selected for the second wireless device is a standardized bandwidth such that the carrier appears to the second wireless device as a standardized bandwidth carrier.

48. A method of operation of a base station in a cellular communications network, comprising:

receiving a random access transmission from a wireless device, the random access transmission comprising information that is indicative of non-standardized bandwidth capabilities of the wireless device;

selecting a system bandwidth for the wireless device based on the non-standardized bandwidth capabilities of the wireless device;

transmitting control information to the wireless device, the control information being indicative of the system bandwidth selected for the wireless device; and

transmitting a carrier such that the carrier appears to the wireless device to have a bandwidth equal to the system bandwidth selected for the wireless device.

49. A wireless device for operation in a cellular communications network, comprising:

a radio subsystem; and

a processing subsystem associated with the radio subsystem and configured to;

transmit a random access transmission from the wireless device to a base station via the radio subsystem, the random access transmission comprising information that is indicative of non-standardized bandwidth capabilities of the wireless device;

receive control information from the base station via the radio subsystem, the control information being indicative of a system bandwidth selected for the wireless device based on the information that is indicative of the non-standardized bandwidth capabilities of the wireless device; and

receive a carrier from the base station via the radio subsystem such that the carrier appears to the wireless device to have a bandwidth equal to the system bandwidth selected for the wireless device.

50. A method of operation of a wireless device in a cellular communications network, comprising:

transmitting a random access transmission from the wireless device to a base station, the random access transmission comprising information that is indicative of non-standardized bandwidth capabilities of the wireless device;

receiving control information from the base station, the control information being indicative of a system bandwidth selected for the wireless device based on the information that is indicative of the non-standardized bandwidth capabilities of the wireless device; and

receiving a carrier from the base station such that the carrier appears to the wireless device to have a bandwidth equal to the system bandwidth selected for the wireless device.